Commit Graph

654 Commits

Author SHA1 Message Date
Paul Gortmaker 67b84999b1 Revert "tracing: Include module.h in define_trace.h"
This reverts commit 3a9f987b31.

With all the files that are real modules now having module.h
explicitly called out for inclusion, and no reliance on any
implicit presence of module.h assumed, we should no longer
need this workaround.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:32:35 -04:00
Paul Gortmaker de47725421 include: replace linux/module.h with "struct module" wherever possible
The <linux/module.h> pretty much brings in the kitchen sink along
with it, so it should be avoided wherever reasonably possible in
terms of being included from other commonly used <linux/something.h>
files, as it results in a measureable increase on compile times.

The worst culprit was probably device.h since it is used everywhere.
This file also had an implicit dependency/usage of mutex.h which was
masked by module.h, and is also fixed here at the same time.

There are over a dozen other headers that simply declare the
struct instead of pulling in the whole file, so follow their lead
and simply make it a few more.

Most of the implicit dependencies on module.h being present by
these headers pulling it in have been now weeded out, so we can
finally make this change with hopefully minimal breakage.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:32:32 -04:00
Curt Wohlgemuth 0e175a1835 writeback: Add a 'reason' to wb_writeback_work
This creates a new 'reason' field in a wb_writeback_work
structure, which unambiguously identifies who initiates
writeback activity.  A 'wb_reason' enumeration has been
added to writeback.h, to enumerate the possible reasons.

The 'writeback_work_class' and tracepoint event class and
'writeback_queue_io' tracepoints are updated to include the
symbolic 'reason' in all trace events.

And the 'writeback_inodes_sbXXX' family of routines has had
a wb_stats parameter added to them, so callers can specify
why writeback is being started.

Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Curt Wohlgemuth <curtw@google.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-10-31 00:33:36 +08:00
Curt Wohlgemuth ad4e38dd6a writeback: send work item to queue_io, move_expired_inodes
Instead of sending ->older_than_this to queue_io() and
move_expired_inodes(), send the entire wb_writeback_work
structure.  There are other fields of a work item that are
useful in these routines and in tracepoints.

Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Curt Wohlgemuth <curtw@google.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-10-31 00:33:27 +08:00
Wu Fengguang ece13ac31b writeback: trace event balance_dirty_pages
Useful for analyzing the dynamics of the throttling algorithms and
debugging user reported problems.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-10-31 00:29:38 +08:00
Wu Fengguang b48c104d22 writeback: trace event bdi_dirty_ratelimit
It helps understand how various throttle bandwidths are updated.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-10-31 00:29:21 +08:00
Linus Torvalds 68d99b2c8e Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (549 commits)
  ALSA: hda - Fix ADC input-amp handling for Cx20549 codec
  ALSA: hda - Keep EAPD turned on for old Conexant chips
  ALSA: hda/realtek - Fix missing volume controls with ALC260
  ASoC: wm8940: Properly set codec->dapm.bias_level
  ALSA: hda - Fix pin-config for ASUS W90V
  ALSA: hda - Fix surround/CLFE headphone and speaker pins order
  ALSA: hda - Fix typo
  ALSA: Update the sound git tree URL
  ALSA: HDA: Add new revision for ALC662
  ASoC: max98095: Convert codec->hw_write to snd_soc_write
  ASoC: keep pointer to resource so it can be freed
  ASoC: sgtl5000: Fix wrong mask in some snd_soc_update_bits calls
  ASoC: wm8996: Fix wrong mask for setting WM8996_AIF_CLOCKING_2
  ASoC: da7210: Add support for line out and DAC
  ASoC: da7210: Add support for DAPM
  ALSA: hda/realtek - Fix DAC assignments of multiple speakers
  ASoC: Use SGTL5000_LINREG_VDDD_MASK instead of hardcoded mask value
  ASoC: Set sgtl5000->ldo in ldo_regulator_register
  ASoC: wm8996: Use SND_SOC_DAPM_AIF_OUT for AIF2 Capture
  ASoC: wm8994: Use SND_SOC_DAPM_AIF_OUT for AIF3 Capture
  ...
2011-10-28 14:25:01 -07:00
Eric Gouriou 6f91bc5fda ext4: optimize ext4_ext_convert_to_initialized()
This patch introduces a fast path in ext4_ext_convert_to_initialized()
for the case when the conversion can be performed by transferring
the newly initialized blocks from the uninitialized extent into
an adjacent initialized extent. Doing so removes the expensive
invocations of memmove() which occur during extent insertion and
the subsequent merge.

In practice this should be the common case for clients performing
append writes into files pre-allocated via
fallocate(FALLOC_FL_KEEP_SIZE). In such a workload performed via
direct IO and when using a suboptimal implementation of memmove()
(x86_64 prior to the 2.6.39 rewrite), this patch reduces kernel CPU
consumption by 32%.

Two new trace points are added to ext4_ext_convert_to_initialized()
to offer visibility into its operations. No exit trace point has
been added due to the multiplicity of return points. This can be
revisited once the upstream cleanup is backported.

Signed-off-by: Eric Gouriou <egouriou@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-10-27 11:43:23 -04:00
Linus Torvalds 8a4a8918ed Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (46 commits)
  llist: Add back llist_add_batch() and llist_del_first() prototypes
  sched: Don't use tasklist_lock for debug prints
  sched: Warn on rt throttling
  sched: Unify the ->cpus_allowed mask copy
  sched: Wrap scheduler p->cpus_allowed access
  sched: Request for idle balance during nohz idle load balance
  sched: Use resched IPI to kick off the nohz idle balance
  sched: Fix idle_cpu()
  llist: Remove cpu_relax() usage in cmpxchg loops
  sched: Convert to struct llist
  llist: Add llist_next()
  irq_work: Use llist in the struct irq_work logic
  llist: Return whether list is empty before adding in llist_add()
  llist: Move cpu_relax() to after the cmpxchg()
  llist: Remove the platform-dependent NMI checks
  llist: Make some llist functions inline
  sched, tracing: Show PREEMPT_ACTIVE state in trace_sched_switch
  sched: Remove redundant test in check_preempt_tick()
  sched: Add documentation for bandwidth control
  sched: Return unused runtime on group dequeue
  ...
2011-10-26 17:08:43 +02:00
Linus Torvalds 7115e3fcf4 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (121 commits)
  perf symbols: Increase symbol KSYM_NAME_LEN size
  perf hists browser: Refuse 'a' hotkey on non symbolic views
  perf ui browser: Use libslang to read keys
  perf tools: Fix tracing info recording
  perf hists browser: Elide DSO column when it is set to just one DSO, ditto for threads
  perf hists: Don't consider filtered entries when calculating column widths
  perf hists: Don't decay total_period for filtered entries
  perf hists browser: Honour symbol_conf.show_{nr_samples,total_period}
  perf hists browser: Do not exit on tab key with single event
  perf annotate browser: Don't change selection line when returning from callq
  perf tools: handle endianness of feature bitmap
  perf tools: Add prelink suggestion to dso update message
  perf script: Fix unknown feature comment
  perf hists browser: Apply the dso and thread filters when merging new batches
  perf hists: Move the dso and thread filters from hist_browser
  perf ui browser: Honour the xterm colors
  perf top tui: Give color hints just on the percentage, like on --stdio
  perf ui browser: Make the colors configurable and change the defaults
  perf tui: Remove unneeded call to newtCls on startup
  perf hists: Don't format the percentage on hist_entry__snprintf
  ...

Fix up conflicts in arch/x86/kernel/kprobes.c manually.

Ingo's tree did the insane "add volatile to const array", which just
doesn't make sense ("volatile const"?).  But we could remove the const
*and* make the array volatile to make doubly sure that gcc doesn't
optimize it away..

Also fix up kernel/trace/ring_buffer.c non-data-conflicts manually: the
reader_lock has been turned into a raw lock by the core locking merge,
and there was a new user of it introduced in this perf core merge.  Make
sure that new use also uses the raw accessor functions.
2011-10-26 17:03:38 +02:00
Linus Torvalds 19b4a8d520 Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (45 commits)
  rcu: Move propagation of ->completed from rcu_start_gp() to rcu_report_qs_rsp()
  rcu: Remove rcu_needs_cpu_flush() to avoid false quiescent states
  rcu: Wire up RCU_BOOST_PRIO for rcutree
  rcu: Make rcu_torture_boost() exit loops at end of test
  rcu: Make rcu_torture_fqs() exit loops at end of test
  rcu: Permit rt_mutex_unlock() with irqs disabled
  rcu: Avoid having just-onlined CPU resched itself when RCU is idle
  rcu: Suppress NMI backtraces when stall ends before dump
  rcu: Prohibit grace periods during early boot
  rcu: Simplify unboosting checks
  rcu: Prevent early boot set_need_resched() from __rcu_pending()
  rcu: Dump local stack if cannot dump all CPUs' stacks
  rcu: Move __rcu_read_unlock()'s barrier() within if-statement
  rcu: Improve rcu_assign_pointer() and RCU_INIT_POINTER() documentation
  rcu: Make rcu_assign_pointer() unconditionally insert a memory barrier
  rcu: Make rcu_implicit_dynticks_qs() locals be correct size
  rcu: Eliminate in_irq() checks in rcu_enter_nohz()
  nohz: Remove nohz_cpu_mask
  rcu: Document interpretation of RCU-lockdep splats
  rcu: Allow rcutorture's stat_interval parameter to be changed at runtime
  ...
2011-10-26 16:26:53 +02:00
Linus Torvalds e33bae14fd Merge branch 'for-linus' of git://github.com/ericvh/linux
* 'for-linus' of git://github.com/ericvh/linux:
  9p: fix 9p.txt to advertise msize instead of maxdata
  net/9p: Convert net/9p protocol dumps to tracepoints
  fs/9p: change an int to unsigned int
  fs/9p: Cleanup option parsing in 9p
  9p: move dereference after NULL check
  fs/9p: inode file operation is properly initialized init_special_inode
  fs/9p: Update zero-copy implementation in 9p
2011-10-26 14:20:53 +02:00
Linus Torvalds 7e0bb71e75 Merge branch 'pm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
* 'pm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (63 commits)
  PM / Clocks: Remove redundant NULL checks before kfree()
  PM / Documentation: Update docs about suspend and CPU hotplug
  ACPI / PM: Add Sony VGN-FW21E to nonvs blacklist.
  ARM: mach-shmobile: sh7372 A4R support (v4)
  ARM: mach-shmobile: sh7372 A3SP support (v4)
  PM / Sleep: Mark devices involved in wakeup signaling during suspend
  PM / Hibernate: Improve performance of LZO/plain hibernation, checksum image
  PM / Hibernate: Do not initialize static and extern variables to 0
  PM / Freezer: Make fake_signal_wake_up() wake TASK_KILLABLE tasks too
  PM / Hibernate: Add resumedelay kernel param in addition to resumewait
  MAINTAINERS: Update linux-pm list address
  PM / ACPI: Blacklist Vaio VGN-FW520F machine known to require acpi_sleep=nonvs
  PM / ACPI: Blacklist Sony Vaio known to require acpi_sleep=nonvs
  PM / Hibernate: Add resumewait param to support MMC-like devices as resume file
  PM / Hibernate: Fix typo in a kerneldoc comment
  PM / Hibernate: Freeze kernel threads after preallocating memory
  PM: Update the policy on default wakeup settings
  PM / VT: Cleanup #if defined uglyness and fix compile error
  PM / Suspend: Off by one in pm_suspend()
  PM / Hibernate: Include storage keys in hibernation image on s390
  ...
2011-10-25 15:18:39 +02:00
Linus Torvalds 4e7e2a2008 Merge branch 'for-linus' of git://opensource.wolfsonmicro.com/regmap
* 'for-linus' of git://opensource.wolfsonmicro.com/regmap: (62 commits)
  mfd: Enable rbtree cache for wm831x devices
  regmap: Support some block operations on cached devices
  regmap: Allow caches for devices with no defaults
  regmap: Ensure rbtree syncs registers set to zero properly
  regmap: Allow rbtree to cache zero default values
  regmap: Warn on raw I/O as well as bulk reads that bypass cache
  regmap: Return a sensible error code if we fail to read the cache
  regmap: Use bsearch() to search the register defaults
  regmap: Fix doc comment
  regmap: Optimize the lookup path to use binary search
  regmap: Ensure we scream if we enable cache bypass/only at the same time
  regmap: Implement regcache_cache_bypass helper function
  regmap: Save/restore the bypass state upon syncing
  regmap: Lock the sync path, ensure we use the lockless _regmap_write()
  regmap: Fix apostrophe usage
  regmap: Make _regmap_write() global
  regmap: Fix lock used for regcache_cache_only()
  regmap: Grab the lock in regcache_cache_only()
  regmap: Modify map->cache_bypass directly
  regmap: Fix regcache_sync generic implementation
  ...
2011-10-25 13:57:45 +02:00
Aneesh Kumar K.V 348b59012e net/9p: Convert net/9p protocol dumps to tracepoints
This helps in more control over debugging.
root@qemu-img-64:~# ls /pass/123
ls: cannot access /pass/123: No such file or directory
root@qemu-img-64:~# cat /sys/kernel/debug/tracing/trace
# tracer: nop
#
#           TASK-PID    CPU#    TIMESTAMP  FUNCTION
#              | |       |          |         |
              ls-1536  [001]    70.928584: 9p_protocol_dump: clnt 18446612132784021504 P9_TWALK(tag = 1)
000: 16 00 00 00 6e 01 00 01 00 00 00 02 00 00 00 01
010: 00 03 00 31 32 33 00 00 00 ff ff ff ff 00 00 00

              ls-1536  [001]    70.928587: <stack trace>
 => trace_9p_protocol_dump
 => p9pdu_finalize
 => p9_client_rpc
 => p9_client_walk
 => v9fs_vfs_lookup
 => d_alloc_and_lookup
 => walk_component
 => path_lookupat
              ls-1536  [000]    70.929696: 9p_protocol_dump: clnt 18446612132784021504 P9_RLERROR(tag = 1)
000: 0b 00 00 00 07 01 00 02 00 00 00 4e 03 00 02 00
010: 00 00 00 00 03 00 02 00 00 00 00 00 ff 43 00 00

              ls-1536  [000]    70.929697: <stack trace>
 => trace_9p_protocol_dump
 => p9_client_rpc
 => p9_client_walk
 => v9fs_vfs_lookup
 => d_alloc_and_lookup
 => walk_component
 => path_lookupat
 => do_path_lookup

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2011-10-24 11:13:12 -05:00
Rafael J. Wysocki d727b60659 Merge branch 'pm-runtime' into pm-for-linus
* pm-runtime:
  PM / Tracing: build rpm-traces.c only if CONFIG_PM_RUNTIME is set
  PM / Runtime: Replace dev_dbg() with trace_rpm_*()
  PM / Runtime: Introduce trace points for tracing rpm_* functions
  PM / Runtime: Don't run callbacks under lock for power.irq_safe set
  USB: Add wakeup info to debugging messages
  PM / Runtime: pm_runtime_idle() can be called in atomic context
  PM / Runtime: Add macro to test for runtime PM events
  PM / Runtime: Add might_sleep() to runtime PM functions
2011-10-07 23:16:55 +02:00
Ingo Molnar 9d01402023 Merge commit 'v3.1-rc9' into perf/core
Merge reason: pick up latest fixes.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-06 12:49:21 +02:00
Ingo Molnar 22f92bacbe Merge branch 'linus' into sched/core
Merge reason: pick up the latest fixes.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-04 11:09:08 +02:00
Andrew Vagin 92e51938f5 perf: Fix counter of ftrace events
Each event adds some points to its counters. By default it adds 1,
and a number of points may be transmited in event's parameters.

E.g. sched:sched_stat_runtime adds how long process has been running.

But this functionality was broken by v2.6.31-rc5-392-gf413cdb
and now the event's parameters doesn't affect on a number of points.

TP_perf_assign isn't defined, so __perf_count(c) isn't executed and
__count is always equal to 1.

Signed-off-by: Andrew Vagin <avagin@openvz.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1317052535-1765247-2-git-send-email-avagin@openvz.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-04 11:07:54 +02:00
Wu Fengguang 143dfe8611 writeback: IO-less balance_dirty_pages()
As proposed by Chris, Dave and Jan, don't start foreground writeback IO
inside balance_dirty_pages(). Instead, simply let it idle sleep for some
time to throttle the dirtying task. In the mean while, kick off the
per-bdi flusher thread to do background writeback IO.

RATIONALS
=========

- disk seeks on concurrent writeback of multiple inodes (Dave Chinner)

  If every thread doing writes and being throttled start foreground
  writeback, it leads to N IO submitters from at least N different
  inodes at the same time, end up with N different sets of IO being
  issued with potentially zero locality to each other, resulting in
  much lower elevator sort/merge efficiency and hence we seek the disk
  all over the place to service the different sets of IO.
  OTOH, if there is only one submission thread, it doesn't jump between
  inodes in the same way when congestion clears - it keeps writing to
  the same inode, resulting in large related chunks of sequential IOs
  being issued to the disk. This is more efficient than the above
  foreground writeback because the elevator works better and the disk
  seeks less.

- lock contention and cache bouncing on concurrent IO submitters (Dave Chinner)

  With this patchset, the fs_mark benchmark on a 12-drive software RAID0 goes
  from CPU bound to IO bound, freeing "3-4 CPUs worth of spinlock contention".

  * "CPU usage has dropped by ~55%", "it certainly appears that most of
    the CPU time saving comes from the removal of contention on the
    inode_wb_list_lock" (IMHO at least 10% comes from the reduction of
    cacheline bouncing, because the new code is able to call much less
    frequently into balance_dirty_pages() and hence access the global
    page states)

  * the user space "App overhead" is reduced by 20%, by avoiding the
    cacheline pollution by the complex writeback code path

  * "for a ~5% throughput reduction", "the number of write IOs have
    dropped by ~25%", and the elapsed time reduced from 41:42.17 to
    40:53.23.

  * On a simple test of 100 dd, it reduces the CPU %system time from 30% to 3%,
    and improves IO throughput from 38MB/s to 42MB/s.

- IO size too small for fast arrays and too large for slow USB sticks

  The write_chunk used by current balance_dirty_pages() cannot be
  directly set to some large value (eg. 128MB) for better IO efficiency.
  Because it could lead to more than 1 second user perceivable stalls.
  Even the current 4MB write size may be too large for slow USB sticks.
  The fact that balance_dirty_pages() starts IO on itself couples the
  IO size to wait time, which makes it hard to do suitable IO size while
  keeping the wait time under control.

  Now it's possible to increase writeback chunk size proportional to the
  disk bandwidth. In a simple test of 50 dd's on XFS, 1-HDD, 3GB ram,
  the larger writeback size dramatically reduces the seek count to 1/10
  (far beyond my expectation) and improves the write throughput by 24%.

- long block time in balance_dirty_pages() hurts desktop responsiveness

  Many of us may have the experience: it often takes a couple of seconds
  or even long time to stop a heavy writing dd/cp/tar command with
  Ctrl-C or "kill -9".

- IO pipeline broken by bumpy write() progress

  There are a broad class of "loop {read(buf); write(buf);}" applications
  whose read() pipeline will be under-utilized or even come to a stop if
  the write()s have long latencies _or_ don't progress in a constant rate.
  The current threshold based throttling inherently transfers the large
  low level IO completion fluctuations to bumpy application write()s,
  and further deteriorates with increasing number of dirtiers and/or bdi's.

  For example, when doing 50 dd's + 1 remote rsync to an XFS partition,
  the rsync progresses very bumpy in legacy kernel, and throughput is
  improved by 67% by this patchset. (plus the larger write chunk size,
  it will be 93% speedup).

  The new rate based throttling can support 1000+ dd's with excellent
  smoothness, low latency and low overheads.

For the above reasons, it's much better to do IO-less and low latency
pauses in balance_dirty_pages().

Jan Kara, Dave Chinner and me explored the scheme to let
balance_dirty_pages() wait for enough writeback IO completions to
safeguard the dirty limit. However it's found to have two problems:

- in large NUMA systems, the per-cpu counters may have big accounting
  errors, leading to big throttle wait time and jitters.

- NFS may kill large amount of unstable pages with one single COMMIT.
  Because NFS server serves COMMIT with expensive fsync() IOs, it is
  desirable to delay and reduce the number of COMMITs. So it's not
  likely to optimize away such kind of bursty IO completions, and the
  resulted large (and tiny) stall times in IO completion based throttling.

So here is a pause time oriented approach, which tries to control the
pause time in each balance_dirty_pages() invocations, by controlling
the number of pages dirtied before calling balance_dirty_pages(), for
smooth and efficient dirty throttling:

- avoid useless (eg. zero pause time) balance_dirty_pages() calls
- avoid too small pause time (less than   4ms, which burns CPU power)
- avoid too large pause time (more than 200ms, which hurts responsiveness)
- avoid big fluctuations of pause times

It can control pause times at will. The default policy (in a followup
patch) will be to do ~10ms pauses in 1-dd case, and increase to ~100ms
in 1000-dd case.

BEHAVIOR CHANGE
===============

(1) dirty threshold

Users will notice that the applications will get throttled once crossing
the global (background + dirty)/2=15% threshold, and then balanced around
17.5%. Before patch, the behavior is to just throttle it at 20% dirtyable
memory in 1-dd case.

Since the task will be soft throttled earlier than before, it may be
perceived by end users as performance "slow down" if his application
happens to dirty more than 15% dirtyable memory.

(2) smoothness/responsiveness

Users will notice a more responsive system during heavy writeback.
"killall dd" will take effect instantly.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-10-03 21:08:57 +08:00
Ingo Molnar 048b718029 Merge branch 'rcu/next' of git://github.com/paulmckrcu/linux into core/rcu 2011-10-01 14:21:36 +02:00
Paul E. McKenney d4c08f2ac3 rcu: Add grace-period, quiescent-state, and call_rcu trace events
Add trace events to record grace-period start and end, quiescent states,
CPUs noticing grace-period start and end, grace-period initialization,
call_rcu() invocation, tasks blocking in RCU read-side critical sections,
tasks exiting those same critical sections, force_quiescent_state()
detection of dyntick-idle and offline CPUs, CPUs entering and leaving
dyntick-idle mode (except from NMIs), CPUs coming online and going
offline, and CPUs being kicked for staying in dyntick-idle mode for too
long (as in many weeks, even on 32-bit systems).

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

rcu: Add the rcu flavor to callback trace events

The earlier trace events for registering RCU callbacks and for invoking
them did not include the RCU flavor (rcu_bh, rcu_preempt, or rcu_sched).
This commit adds the RCU flavor to those trace events.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-09-28 21:38:21 -07:00
Paul E. McKenney 385680a948 rcu: Add event-trace markers to TREE_RCU kthreads
Add event-trace markers to TREE_RCU kthreads to allow including these
kthread's CPU time in the utilization calculations.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-09-28 21:38:19 -07:00
Paul E. McKenney 72fe701b70 rcu: Add RCU type to callback-invocation tracing
Add a string to the rcu_batch_start() and rcu_batch_end() trace
messages that indicates the RCU type ("rcu_sched", "rcu_bh", or
"rcu_preempt").  The trace messages for the actual invocations
themselves are not marked, as it should be clear from the
rcu_batch_start() and rcu_batch_end() events before and after.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-09-28 21:38:15 -07:00
Paul E. McKenney 300df91ca9 rcu: Event-trace markers for computing RCU CPU utilization
This commit adds the trace_rcu_utilization() marker that is to be
used to allow postprocessing scripts compute RCU's CPU utilization,
give or take event-trace overhead.  Note that we do not include RCU's
dyntick-idle interface because event tracing requires RCU protection,
which is not available in dyntick-idle mode.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-09-28 21:38:13 -07:00
Paul E. McKenney 29c00b4a1d rcu: Add event-tracing for RCU callback invocation
There was recently some controversy about the overhead of invoking RCU
callbacks.  Add TRACE_EVENT()s to obtain fine-grained timings for the
start and stop of a batch of callbacks and also for each callback invoked.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-09-28 21:38:12 -07:00
Ming Lei 53b615ccca PM / Runtime: Introduce trace points for tracing rpm_* functions
This patch introduces 3 trace points to prepare for tracing
rpm_idle/rpm_suspend/rpm_resume functions, so we can use these
trace points to replace the current dev_dbg().

Signed-off-by: Ming Lei <ming.lei@canonical.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-09-27 22:53:27 +02:00
Peter Zijlstra 557ab42542 sched, tracing: Show PREEMPT_ACTIVE state in trace_sched_switch
We had need to see the difference between scheduling a runnable task and
a runnable task being involuntarily preempted.

No app should rely on the old string output (the binary
trace event record format is not changed).

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1316164603.10174.11.camel@twins
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-09-26 13:25:54 +02:00
Mark Brown e56235e099 ASoC: Add another DAPM stat for neighbour checks
The number of times we look at a potentially connected neighbour is just
as important as the number of times we actually recurse into looking at
that neighbour so also collect that statistic.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-22 17:24:40 +01:00
Mark Brown de02d0786d ASoC: Trace and collect statistics for DAPM graph walking
One of the longest standing areas for improvement in ASoC has been the
DAPM algorithm - it repeats the same checks many times whenever it is run
and makes no effort to limit the areas of the graph it checks meaning we
do an awful lot of walks over the full graph. This has never mattered too
much as the size of the graph has generally been small in relation to the
size of the devices supported and the speed of CPUs but it is annoying.

In preparation for work on improving this insert a trace point after the
graph walk has been done. This gives us specific timing information for
the walk, and in order to give quantifiable (non-benchmark) numbers also
count every time we check a link or check the power for a widget and report
those numbers. Substantial changes in the algorithm may require tweaks to
the stats but they should be useful for simpler things.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-21 14:53:44 +01:00
Dimitris Papastamos 5936008901 regmap: Add the regcache_sync trace event
Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 19:06:34 +01:00
Aditya Kali d8990240d8 ext4: add some tracepoints in ext4/extents.c
This patch adds some tracepoints in ext4/extents.c and updates a tracepoint in
ext4/inode.c.

Tested: Built and ran the kernel and verified that these tracepoints work.
Also ran xfstests.

Signed-off-by: Aditya Kali <adityakali@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-09-09 19:18:51 -04:00
Wu Fengguang c8ad620638 writeback: show raw dirtied_when in trace writeback_single_inode
Save inode->dirtied_when in the raw trace output for reliable scripting,
and to also show in formatted output the relative age in seconds for
easy human reading.

CC: Jan Kara <jack@suse.cz>
Acked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-08-31 08:48:15 +08:00
Linus Torvalds 5ccc38740a Merge branch 'for-linus' of git://git.kernel.dk/linux-block
* 'for-linus' of git://git.kernel.dk/linux-block: (23 commits)
  Revert "cfq: Remove special treatment for metadata rqs."
  block: fix flush machinery for stacking drivers with differring flush flags
  block: improve rq_affinity placement
  blktrace: add FLUSH/FUA support
  Move some REQ flags to the common bio/request area
  allow blk_flush_policy to return REQ_FSEQ_DATA independent of *FLUSH
  xen/blkback: Make description more obvious.
  cfq-iosched: Add documentation about idling
  block: Make rq_affinity = 1 work as expected
  block: swim3: fix unterminated of_device_id table
  block/genhd.c: remove useless cast in diskstats_show()
  drivers/cdrom/cdrom.c: relax check on dvd manufacturer value
  drivers/block/drbd/drbd_nl.c: use bitmap_parse instead of __bitmap_parse
  bsg-lib: add module.h include
  cfq-iosched: Reduce linked group count upon group destruction
  blk-throttle: correctly determine sync bio
  loop: fix deadlock when sysfs and LOOP_CLR_FD race against each other
  loop: add BLK_DEV_LOOP_MIN_COUNT=%i to allow distros 0 pre-allocated loop devices
  loop: add management interface for on-demand device allocation
  loop: replace linked list of allocated devices with an idr index
  ...
2011-08-19 10:47:07 -07:00
Namhyung Kim c09c47caed blktrace: add FLUSH/FUA support
Add FLUSH/FUA support to blktrace. As FLUSH precedes WRITE and/or
FUA follows WRITE, use the same 'F' flag for both cases and
distinguish them by their (relative) position. The end results
look like (other flags might be shown also):

 - WRITE:            W
 - WRITE_FLUSH:      FW
 - WRITE_FUA:        WF
 - WRITE_FLUSH_FUA:  FWF

Note that we reuse TC_BARRIER due to lack of bit space of act_mask
so that the older versions of blktrace tools will report flush
requests as barriers from now on.

Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-08-11 10:36:05 +02:00
Mark Brown 3d9ead7c06 regmap: Use int rather than size_t for lengths when logging blocks
x86_64 warns as size_t is not an int.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
2011-08-10 00:26:33 +09:00
Mark Brown fb2736bbae regmap: Add basic tracepoints
Trace single register reads and writes, plus start/stop tracepoints for
the actual I/O to see where we're spending time. This makes it easy to
have always on logging without overwhelming the logs and also lets us take
advantage of all the context and time information that the trace subsystem
collects for us.

We don't currently trace register values for bulk operations as this would
add complexity and overhead parsing the cooked data that's being worked
with.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-08-08 15:56:16 +09:00
Linus Torvalds 60ad446682 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (60 commits)
  ext4: prevent memory leaks from ext4_mb_init_backend() on error path
  ext4: use EXT4_BAD_INO for buddy cache to avoid colliding with valid inode #
  ext4: use ext4_msg() instead of printk in mballoc
  ext4: use ext4_kvzalloc()/ext4_kvmalloc() for s_group_desc and s_group_info
  ext4: introduce ext4_kvmalloc(), ext4_kzalloc(), and ext4_kvfree()
  ext4: use the correct error exit path in ext4_init_inode_table()
  ext4: add missing kfree() on error return path in add_new_gdb()
  ext4: change umode_t in tracepoint headers to be an explicit __u16
  ext4: fix races in ext4_sync_parent()
  ext4: Fix overflow caused by missing cast in ext4_fallocate()
  ext4: add action of moving index in ext4_ext_rm_idx for Punch Hole
  ext4: simplify parameters of reserve_backup_gdb()
  ext4: simplify parameters of add_new_gdb()
  ext4: remove lock_buffer in bclean() and setup_new_group_blocks()
  ext4: simplify journal handling in setup_new_group_blocks()
  ext4: let setup_new_group_blocks() set multiple bits at a time
  ext4: fix a typo in ext4_group_extend()
  ext4: let ext4_group_add_blocks() handle 0 blocks quickly
  ext4: let ext4_group_add_blocks() return an error code
  ext4: rename ext4_add_groupblocks() to ext4_group_add_blocks()
  ...

Fix up conflict in fs/ext4/inode.c: commit aacfc19c62 ("fs: simplify
the blockdev_direct_IO prototype") had changed the ext4_ind_direct_IO()
function for the new simplified calling convention, while commit
dae1e52cb1 ("ext4: move ext4_ind_* functions from inode.c to
indirect.c") moved the function to another file.
2011-08-01 13:56:03 -10:00
Theodore Ts'o 59be8e7280 ext4: change umode_t in tracepoint headers to be an explicit __u16
As requested by Al Viro, since umode_t may be changing to a u32 for
some architectures.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
2011-07-30 12:38:46 -04:00
Linus Torvalds b993fdbc7f Merge branch 'upstream/xen-tracing2' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen
* 'upstream/xen-tracing2' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
  xen/tracing: fix compile errors when tracing is disabled.
2011-07-29 23:33:40 -07:00
Linus Torvalds 2ac232f37f Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6:
  jbd: change the field "b_cow_tid" of struct journal_head from type unsigned to tid_t
  ext3.txt: update the links in the section "useful links" to the latest ones
  ext3: Fix data corruption in inodes with journalled data
  ext2: check xattr name_len before acquiring xattr_sem in ext2_xattr_get
  ext3: Fix compilation with -DDX_DEBUG
  quota: Remove unused declaration
  jbd: Use WRITE_SYNC in journal checkpoint.
  jbd: Fix oops in journal_remove_journal_head()
  ext3: Return -EINVAL when start is beyond the end of fs in ext3_trim_fs()
  ext3/ioctl.c: silence sparse warnings about different address spaces
  ext3/ext4 Documentation: remove bh/nobh since it has been deprecated
  ext3: Improve truncate error handling
  ext3: use proper little-endian bitops
  ext2: include fs.h into ext2_fs.h
  ext3: Fix oops in ext3_try_to_allocate_with_rsv()
  jbd: fix a bug of leaking jh->b_jcount
  jbd: remove dependency on __GFP_NOFAIL
  ext3: Convert ext3 to new truncate calling convention
  jbd: Add fixed tracepoints
  ext3: Add fixed tracepoints

Resolve conflicts in fs/ext3/fsync.c due to fsync locking push-down and
new fixed tracepoints.
2011-07-26 11:34:40 -07:00
Linus Torvalds f01ef569cd Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/writeback
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/writeback: (27 commits)
  mm: properly reflect task dirty limits in dirty_exceeded logic
  writeback: don't busy retry writeback on new/freeing inodes
  writeback: scale IO chunk size up to half device bandwidth
  writeback: trace global_dirty_state
  writeback: introduce max-pause and pass-good dirty limits
  writeback: introduce smoothed global dirty limit
  writeback: consolidate variable names in balance_dirty_pages()
  writeback: show bdi write bandwidth in debugfs
  writeback: bdi write bandwidth estimation
  writeback: account per-bdi accumulated written pages
  writeback: make writeback_control.nr_to_write straight
  writeback: skip tmpfs early in balance_dirty_pages_ratelimited_nr()
  writeback: trace event writeback_queue_io
  writeback: trace event writeback_single_inode
  writeback: remove .nonblocking and .encountered_congestion
  writeback: remove writeback_control.more_io
  writeback: skip balance_dirty_pages() for in-memory fs
  writeback: add bdi_dirty_limit() kernel-doc
  writeback: avoid extra sync work at enqueue time
  writeback: elevate queue_io() into wb_writeback()
  ...

Fix up trivial conflicts in fs/fs-writeback.c and mm/filemap.c
2011-07-26 10:39:54 -07:00
Jeremy Fitzhardinge b3c4b98250 xen/tracing: fix compile errors when tracing is disabled.
When CONFIG_FUNCTION_TRACER is disabled, compilation fails as follows:
  CC      arch/x86/xen/setup.o
In file included from arch/x86/include/asm/xen/hypercall.h:42,
                 from arch/x86/xen/setup.c:19:
include/trace/events/xen.h:31: warning: 'struct multicall_entry' declared inside parameter list
include/trace/events/xen.h:31: warning: its scope is only this definition or declaration, which is probably not what you want
include/trace/events/xen.h:31: warning: 'struct multicall_entry' declared inside parameter list
include/trace/events/xen.h:31: warning: 'struct multicall_entry' declared inside parameter list
include/trace/events/xen.h:31: warning: 'struct multicall_entry' declared inside parameter list
[...]
arch/x86/xen/trace.c:5: error: '__HYPERVISOR_set_trap_table' undeclared here (not in a function)
arch/x86/xen/trace.c:5: error: array index in initializer not of integer type
arch/x86/xen/trace.c:5: error: (near initialization for 'xen_hypercall_names')
arch/x86/xen/trace.c:6: error: '__HYPERVISOR_mmu_update' undeclared here (not in a function)
arch/x86/xen/trace.c:6: error: array index in initializer not of integer type
arch/x86/xen/trace.c:6: error: (near initialization for 'xen_hypercall_names')

Fix this by making sure struct multicall_entry has a declaration in
scope at all times, and don't bother compiling xen/trace.c when tracing
is disabled.

Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-07-25 15:51:02 -07:00
Linus Torvalds c61264f98c Merge branch 'upstream/xen-tracing2' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen
* 'upstream/xen-tracing2' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
  xen/trace: use class for multicall trace
  xen/trace: convert mmu events to use DECLARE_EVENT_CLASS()/DEFINE_EVENT()
  xen/multicall: move *idx fields to start of mc_buffer
  xen/multicall: special-case singleton hypercalls
  xen/multicalls: add unlikely around slowpath in __xen_mc_entry()
  xen/multicalls: disable MC_DEBUG
  xen/mmu: tune pgtable alloc/release
  xen/mmu: use extend_args for more mmuext updates
  xen/trace: add tlb flush tracepoints
  xen/trace: add segment desc tracing
  xen/trace: add xen_pgd_(un)pin tracepoints
  xen/trace: add ptpage alloc/release tracepoints
  xen/trace: add mmu tracepoints
  xen/trace: add multicall tracing
  xen/trace: set up tracepoint skeleton
  xen/multicalls: remove debugfs stats
  trace/xen: add skeleton for Xen trace events
2011-07-24 09:06:47 -07:00
Linus Torvalds e498037105 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6: (297 commits)
  ALSA: asihpi - Replace with snd_ctl_boolean_mono_info()
  ALSA: asihpi - HPI version 4.08
  ALSA: asihpi - Add volume mute controls
  ALSA: asihpi - Control name updates
  ALSA: asihpi - Use size_t for sizeof result
  ALSA: asihpi - Explicitly include mutex.h
  ALSA: asihpi - Add new node and message defines
  ALSA: asihpi - Make local function static
  ALSA: asihpi - Fix minor typos and spelling
  ALSA: asihpi - Remove unused structures, macros and functions
  ALSA: asihpi - Remove spurious adapter index check
  ALSA: asihpi - Revise snd_pcm_debug_name, get rid of DEBUG_NAME macro
  ALSA: asihpi - DSP code loader API now independent of OS
  ALSA: asihpi - Remove controlex structs and associated special data transfer code
  ALSA: asihpi - Increase request and response buffer sizes
  ALSA: asihpi - Give more meaningful name to hpi request message type
  ALSA: usb-audio - Add quirk for  Roland / BOSS BR-800
  ALSA: hda - Remove a superfluous argument of via_auto_init_output()
  ALSA: hda - Fix indep-HP path (de-)activation for VT1708* codecs
  ALSA: hda - Add documentation for codec-specific mixer controls
  ...
2011-07-23 10:59:37 -07:00
Linus Torvalds bbd9d6f7fb Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (107 commits)
  vfs: use ERR_CAST for err-ptr tossing in lookup_instantiate_filp
  isofs: Remove global fs lock
  jffs2: fix IN_DELETE_SELF on overwriting rename() killing a directory
  fix IN_DELETE_SELF on overwriting rename() on ramfs et.al.
  mm/truncate.c: fix build for CONFIG_BLOCK not enabled
  fs:update the NOTE of the file_operations structure
  Remove dead code in dget_parent()
  AFS: Fix silly characters in a comment
  switch d_add_ci() to d_splice_alias() in "found negative" case as well
  simplify gfs2_lookup()
  jfs_lookup(): don't bother with . or ..
  get rid of useless dget_parent() in btrfs rename() and link()
  get rid of useless dget_parent() in fs/btrfs/ioctl.c
  fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers
  drivers: fix up various ->llseek() implementations
  fs: handle SEEK_HOLE/SEEK_DATA properly in all fs's that define their own llseek
  Ext4: handle SEEK_HOLE/SEEK_DATA generically
  Btrfs: implement our own ->llseek
  fs: add SEEK_HOLE and SEEK_DATA flags
  reiserfs: make reiserfs default to barrier=flush
  ...

Fix up trivial conflicts in fs/xfs/linux-2.6/xfs_super.c due to the new
shrinker callout for the inode cache, that clashed with the xfs code to
start the periodic workers later.
2011-07-22 19:02:39 -07:00
Takashi Iwai 13b137ef03 Merge branch 'topic/asoc' into for-linus 2011-07-22 08:43:19 +02:00
Dave Chinner 095760730c vmscan: add shrink_slab tracepoints
It is impossible to understand what the shrinkers are actually doing
without instrumenting the code, so add a some tracepoints to allow
insight to be gained.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 01:44:27 -04:00
Jeremy Fitzhardinge bd9ddc875b xen/trace: use class for multicall trace
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-07-18 15:43:46 -07:00
Jeremy Fitzhardinge c43ed60cbf xen/trace: convert mmu events to use DECLARE_EVENT_CLASS()/DEFINE_EVENT()
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-07-18 15:43:46 -07:00
Jeremy Fitzhardinge c8eed1719a xen/trace: add tlb flush tracepoints
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-07-18 15:43:27 -07:00
Jeremy Fitzhardinge ab78f7ad2c xen/trace: add segment desc tracing
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-07-18 15:43:27 -07:00
Jeremy Fitzhardinge 5f94fb5b8e xen/trace: add xen_pgd_(un)pin tracepoints
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-07-18 15:43:27 -07:00
Jeremy Fitzhardinge c2ba050d2e xen/trace: add ptpage alloc/release tracepoints
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-07-18 15:43:27 -07:00
Jeremy Fitzhardinge 8470880791 xen/trace: add mmu tracepoints
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-07-18 15:43:27 -07:00
Jeremy Fitzhardinge c796f213a6 xen/trace: add multicall tracing
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-07-18 15:43:26 -07:00
Jeremy Fitzhardinge 634355d42b trace/xen: add skeleton for Xen trace events
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-07-18 15:42:37 -07:00
Tao Ma b3d4c2b10b ext4: Add new ext4 trim tracepoints
Add ext4_trim_extent and ext4_trim_all_free.

Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-07-11 00:01:52 -04:00
Theodore Ts'o 12706394bc ext4: add tracepoint for ext4_journal_start
This will help debug who is responsible for starting a jbd2 transaction.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-07-10 22:37:50 -04:00
Theodore Ts'o 4862fd6047 jbd2: remove jbd2_dev_to_name() from jbd2 tracepoints
Using function calls in TP_printk causes perf heartburn, so print the
MAJOR/MINOR device numbers instead.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-07-10 22:05:08 -04:00
Wu Fengguang e1cbe23601 writeback: trace global_dirty_state
Add trace event balance_dirty_state for showing the global dirty page
counts and thresholds at each global_dirty_limits() invocation.  This
will cover the callers throttle_vm_writeout(), over_bground_thresh()
and each balance_dirty_pages() loop.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-07-09 22:09:03 -07:00
Wu Fengguang d46db3d582 writeback: make writeback_control.nr_to_write straight
Pass struct wb_writeback_work all the way down to writeback_sb_inodes(),
and initialize the struct writeback_control there.

struct writeback_control is basically designed to control writeback of a
single file, but we keep abuse it for writing multiple files in
writeback_sb_inodes() and its callers.

It immediately clean things up, e.g. suddenly wbc.nr_to_write vs
work->nr_pages starts to make sense, and instead of saving and restoring
pages_skipped in writeback_sb_inodes it can always start with a clean
zero value.

It also makes a neat IO pattern change: large dirty files are now
written in the full 4MB writeback chunk size, rather than whatever
remained quota in wbc->nr_to_write.

Acked-by: Jan Kara <jack@suse.cz>
Proposed-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-07-09 22:09:01 -07:00
David S. Miller e12fe68ce3 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 2011-07-05 23:23:37 -07:00
Liam Girdwood a82ce2ae0d ASoC: core - Add platform IO tracing
Trace platform IO just like CODEC IO.

Signed-off-by: Liam Girdwood <lrg@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-07-05 11:08:10 -07:00
Lukas Czerner 99cb1a318c jbd: Add fixed tracepoints
This commit adds fixed tracepoint for jbd. It has been based on fixed
tracepoints for jbd2, however there are missing those for collecting
statistics, since I think that it will require more intrusive patch so I
should have its own commit, if someone decide that it is needed. Also
there are new tracepoints in __journal_drop_transaction() and
journal_update_superblock().

The list of jbd tracepoints:

jbd_checkpoint
jbd_start_commit
jbd_commit_locking
jbd_commit_flushing
jbd_commit_logging
jbd_drop_transaction
jbd_end_commit
jbd_do_submit_data
jbd_cleanup_journal_tail
jbd_update_superblock_end

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jan Kara <jack@suse.cz>
2011-06-25 17:29:51 +02:00
Lukas Czerner 785c4bcc0d ext3: Add fixed tracepoints
This commit adds fixed tracepoints to the ext3 code. It is based on ext4
tracepoints, however due to the differences of both file systems, there
are some tracepoints missing (those for delaloc and for multi-block
allocator) and there are some ext3 specific as well (for reservation
windows).

Here is a list:

ext3_free_inode
ext3_request_inode
ext3_allocate_inode
ext3_evict_inode
ext3_drop_inode
ext3_mark_inode_dirty
ext3_write_begin
ext3_ordered_write_end
ext3_writeback_write_end
ext3_journalled_write_end
ext3_ordered_writepage
ext3_writeback_writepage
ext3_journalled_writepage
ext3_readpage
ext3_releasepage
ext3_invalidatepage
ext3_discard_blocks
ext3_request_blocks
ext3_allocate_blocks
ext3_free_blocks
ext3_sync_file_enter
ext3_sync_file_exit
ext3_sync_fs
ext3_rsv_window_add
ext3_discard_reservation
ext3_alloc_new_reservation
ext3_reserved
ext3_forget
ext3_read_block_bitmap
ext3_direct_IO_enter
ext3_direct_IO_exit
ext3_unlink_enter
ext3_unlink_exit
ext3_truncate_enter
ext3_truncate_exit
ext3_get_blocks_enter
ext3_get_blocks_exit
ext3_load_inode

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jan Kara <jack@suse.cz>
2011-06-25 17:29:51 +02:00
Satoru Moriya 3847ce32ae core: add tracepoints for queueing skb to rcvbuf
This patch adds 2 tracepoints to get a status of a socket receive queue
and related parameter.

One tracepoint is added to sock_queue_rcv_skb. It records rcvbuf size
and its usage. The other tracepoint is added to __sk_mem_schedule and
it records limitations of memory for sockets and current usage.

By using these tracepoints we're able to know detailed reason why kernel
drop the packet.

Signed-off-by: Satoru Moriya <satoru.moriya@hds.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-21 16:06:10 -07:00
Satoru Moriya 296f7ea75b udp: add tracepoints for queueing skb to rcvbuf
This patch adds a tracepoint to __udp_queue_rcv_skb to get the
return value of ip_queue_rcv_skb. It indicates why kernel drops
a packet at this point.

ip_queue_rcv_skb returns following values in the packet drop case:

rcvbuf is full                 : -ENOMEM
sk_filter returns error        : -EINVAL, -EACCESS, -ENOMEM, etc.
__sk_mem_schedule returns error: -ENOBUF

Signed-off-by: Satoru Moriya <satoru.moriya@hds.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-21 16:06:10 -07:00
Linus Torvalds 890879cfa0 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  jbd2: Fix oops in jbd2_journal_remove_journal_head()
  jbd2: Remove obsolete parameters in the comments for some jbd2 functions
  ext4: fixed tracepoints cleanup
  ext4: use FIEMAP_EXTENT_LAST flag for last extent in fiemap
  ext4: Fix max file size and logical block counting of extent format file
  ext4: correct comments for ext4_free_blocks()
2011-06-21 10:22:35 -07:00
Linus Torvalds 357ed6b1a1 Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  rcu: Move RCU_BOOST #ifdefs to header file
  rcu: use softirq instead of kthreads except when RCU_BOOST=y
  rcu: Use softirq to address performance regression
  rcu: Simplify curing of load woes
2011-06-19 08:56:56 -07:00
KOSAKI Motohiro d7911ef30c vmscan: implement swap token priority aging
While testing for memcg aware swap token, I observed a swap token was
often grabbed an intermittent running process (eg init, auditd) and they
never release a token.

Why?

Some processes (eg init, auditd, audispd) wake up when a process exiting.
And swap token can be get first page-in process when a process exiting
makes no swap token owner.  Thus such above intermittent running process
often get a token.

And currently, swap token priority is only decreased at page fault path.
Then, if the process sleep immediately after to grab swap token, the swap
token priority never be decreased.  That's obviously undesirable.

This patch implement very poor (and lightweight) priority aging.  It only
be affect to the above corner case and doesn't change swap tendency
workload performance (eg multi process qsbench load)

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-15 20:03:59 -07:00
KOSAKI Motohiro 83cd81a343 vmscan: implement swap token trace
This is useful for observing swap token activity.

example output:

             zsh-1845  [000]   598.962716: update_swap_token_priority:
mm=ffff88015eaf7700 old_prio=1 new_prio=0
          memtoy-1830  [001]   602.033900: update_swap_token_priority:
mm=ffff880037a45880 old_prio=947 new_prio=949
          memtoy-1830  [000]   602.041509: update_swap_token_priority:
mm=ffff880037a45880 old_prio=949 new_prio=951
          memtoy-1830  [000]   602.051959: update_swap_token_priority:
mm=ffff880037a45880 old_prio=951 new_prio=953
          memtoy-1830  [000]   602.052188: update_swap_token_priority:
mm=ffff880037a45880 old_prio=953 new_prio=955
          memtoy-1830  [001]   602.427184: put_swap_token:
token_mm=ffff880037a45880
             zsh-1789  [000]   602.427281: replace_swap_token:
old_token_mm=          (null) old_prio=0 new_token_mm=ffff88015eaf7018
new_prio=2
             zsh-1789  [001]   602.433456: update_swap_token_priority:
mm=ffff88015eaf7018 old_prio=2 new_prio=4
             zsh-1789  [000]   602.437613: update_swap_token_priority:
mm=ffff88015eaf7018 old_prio=4 new_prio=6
             zsh-1789  [000]   602.443924: update_swap_token_priority:
mm=ffff88015eaf7018 old_prio=6 new_prio=8
             zsh-1789  [000]   602.451873: update_swap_token_priority:
mm=ffff88015eaf7018 old_prio=8 new_prio=10
             zsh-1789  [001]   602.462639: update_swap_token_priority:
mm=ffff88015eaf7018 old_prio=10 new_prio=12

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Rik van Riel<riel@redhat.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-15 20:03:59 -07:00
Shaohua Li 09223371de rcu: Use softirq to address performance regression
Commit a26ac2455ffcf3(rcu: move TREE_RCU from softirq to kthread)
introduced performance regression. In an AIM7 test, this commit degraded
performance by about 40%.

The commit runs rcu callbacks in a kthread instead of softirq. We observed
high rate of context switch which is caused by this. Out test system has
64 CPUs and HZ is 1000, so we saw more than 64k context switch per second
which is caused by RCU's per-CPU kthread.  A trace showed that most of
the time the RCU per-CPU kthread doesn't actually handle any callbacks,
but instead just does a very small amount of work handling grace periods.
This means that RCU's per-CPU kthreads are making the scheduler do quite
a bit of work in order to allow a very small amount of RCU-related
processing to be done.

Alex Shi's analysis determined that this slowdown is due to lock
contention within the scheduler.  Unfortunately, as Peter Zijlstra points
out, the scheduler's real-time semantics require global action, which
means that this contention is inherent in real-time scheduling.  (Yes,
perhaps someone will come up with a workaround -- otherwise, -rt is not
going to do well on large SMP systems -- but this patch will work around
this issue in the meantime.  And "the meantime" might well be forever.)

This patch therefore re-introduces softirq processing to RCU, but only
for core RCU work.  RCU callbacks are still executed in kthread context,
so that only a small amount of RCU work runs in softirq context in the
common case.  This should minimize ksoftirqd execution, allowing us to
skip boosting of ksoftirqd for CONFIG_RCU_BOOST=y kernels.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Tested-by: "Alex,Shi" <alex.shi@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-06-14 15:25:39 -07:00
Wu Fengguang e84d0a4f8e writeback: trace event writeback_queue_io
Note that it adds a little overheads to account the moved/enqueued
inodes from b_dirty to b_io. The "moved" accounting may be later used to
limit the number of inodes that can be moved in one shot, in order to
keep spinlock hold time under control.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-06-08 08:25:23 +08:00
Wu Fengguang 251d6a471c writeback: trace event writeback_single_inode
It is valuable to know how the dirty inodes are iterated and their IO size.

"writeback_single_inode: bdi 8:0: ino=134246746 state=I_DIRTY_SYNC|I_SYNC age=414 index=0 to_write=1024 wrote=0"

- "state" reflects inode->i_state at the end of writeback_single_inode()
- "index" reflects mapping->writeback_index after the ->writepages() call
- "to_write" is the wbc->nr_to_write at entrance of writeback_single_inode()
- "wrote" is the number of pages actually written

v2: add trace event writeback_single_inode_requeue as proposed by Dave.

CC: Dave Chinner <david@fromorbit.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-06-08 08:25:23 +08:00
Wu Fengguang 846d5a091b writeback: remove .nonblocking and .encountered_congestion
Remove two unused struct writeback_control fields:

	.encountered_congestion	(completely unused)
	.nonblocking		(never set, checked/showed in XFS,NFS/btrfs)

The .for_background check in nfs_write_inode() is also removed btw,
as .for_background implies WB_SYNC_NONE.

Reviewed-by: Jan Kara <jack@suse.cz>
Proposed-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-06-08 08:25:23 +08:00
Wu Fengguang b7a2441f99 writeback: remove writeback_control.more_io
When wbc.more_io was first introduced, it indicates whether there are
at least one superblock whose s_more_io contains more IO work. Now with
the per-bdi writeback, it can be replaced with a simple b_more_io test.

Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-06-08 08:25:23 +08:00
Lukas Czerner a9c667f8f0 ext4: fixed tracepoints cleanup
While creating fixed tracepoints for ext3, basically by porting them
from ext4, I found a lot of useless retyping, wrong type usage, useless
variable passing and other inconsistencies in the ext4 fixed tracepoint
code.

This patch cleans the fixed tracepoint code for ext4 and also simplify
some of them.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-06-06 09:51:52 -04:00
Linus Torvalds 0e833d8cfc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (40 commits)
  tg3: Fix tg3_skb_error_unmap()
  net: tracepoint of net_dev_xmit sees freed skb and causes panic
  drivers/net/can/flexcan.c: add missing clk_put
  net: dm9000: Get the chip in a known good state before enabling interrupts
  drivers/net/davinci_emac.c: add missing clk_put
  af-packet: Add flag to distinguish VID 0 from no-vlan.
  caif: Fix race when conditionally taking rtnl lock
  usbnet/cdc_ncm: add missing .reset_resume hook
  vlan: fix typo in vlan_dev_hard_start_xmit()
  net/ipv4: Check for mistakenly passed in non-IPv4 address
  iwl4965: correctly validate temperature value
  bluetooth l2cap: fix locking in l2cap_global_chan_by_psm
  ath9k: fix two more bugs in tx power
  cfg80211: don't drop p2p probe responses
  Revert "net: fix section mismatches"
  drivers/net/usb/catc.c: Fix potential deadlock in catc_ctrl_run()
  sctp: stop pending timers and purge queues when peer restart asoc
  drivers/net: ks8842 Fix crash on received packet when in PIO mode.
  ip_options_compile: properly handle unaligned pointer
  iwlagn: fix incorrect PCI subsystem id for 6150 devices
  ...
2011-06-04 23:16:00 +09:00
Koki Sanagi ec764bf083 net: tracepoint of net_dev_xmit sees freed skb and causes panic
Because there is a possibility that skb is kfree_skb()ed and zero cleared
after ndo_start_xmit, we should not see the contents of skb like skb->len and
skb->dev->name after ndo_start_xmit. But trace_net_dev_xmit does that
and causes panic by NULL pointer dereference.
This patch fixes trace_net_dev_xmit not to see the contents of skb directly.

If you want to reproduce this panic,

1. Get tracepoint of net_dev_xmit on
2. Create 2 guests on KVM
2. Make 2 guests use virtio_net
4. Execute netperf from one to another for a long time as a network burden
5. host will panic(It takes about 30 minutes)

Signed-off-by: Koki Sanagi <sanagi.koki@jp.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-02 14:06:31 -07:00
Linus Torvalds c4a227d89f Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (25 commits)
  perf: Fix SIGIO handling
  perf top: Don't stop if no kernel symtab is found
  perf top: Handle kptr_restrict
  perf top: Remove unused macro
  perf events: initialize fd array to -1 instead of 0
  perf tools: Make sure kptr_restrict warnings fit 80 col terms
  perf tools: Fix build on older systems
  perf symbols: Handle /proc/sys/kernel/kptr_restrict
  perf: Remove duplicate headers
  ftrace: Add internal recursive checks
  tracing: Update btrfs's tracepoints to use u64 interface
  tracing: Add __print_symbolic_u64 to avoid warnings on 32bit machine
  ftrace: Set ops->flag to enabled even on static function tracing
  tracing: Have event with function tracer check error return
  ftrace: Have ftrace_startup() return failure code
  jump_label: Check entries limit in __jump_label_update
  ftrace/recordmcount: Avoid STT_FUNC symbols as base on ARM
  scripts/tags.sh: Add magic for trace-events for etags too
  scripts/tags.sh: Fix ctags for DEFINE_EVENT()
  x86/ftrace: Fix compiler warning in ftrace.c
  ...
2011-05-28 12:55:55 -07:00
Linus Torvalds 8b29336fe0 Merge branch 'gpio/next' of git://git.secretlab.ca/git/linux-2.6
* 'gpio/next' of git://git.secretlab.ca/git/linux-2.6:
  gpio/via: rename VIA local config struct
  basic_mmio_gpio: split into a gpio library and platform device
  gpio: remove some legacy comments in build files
  gpio: add trace events for setting direction and value
  gpio/pca953x: Use handle_simple_irq instead of handle_edge_irq
  gpiolib: export gpiochip_find
  gpio: remove redundant Kconfig depends on GPIOLIB
  basic_mmio_gpio: convert to non-__raw* accessors
  basic_mmio_gpio: support direction registers
  basic_mmio_gpio: support different input/output registers
  basic_mmio_gpio: detect output method at probe time
  basic_mmio_gpio: request register regions
  basic_mmio_gpio: allow overriding number of gpio
  basic_mmio_gpio: convert to platform_{get,set}_drvdata()
  basic_mmio_gpio: remove runtime width/endianness evaluation
2011-05-26 12:14:41 -07:00
liubo 7f34b746f7 tracing: Update btrfs's tracepoints to use u64 interface
To avoid 64->32 truncating WARNING, update btrfs's tracepoints.

Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Link: http://lkml.kernel.org/r/4DACE6E3.8080200@cn.fujitsu.com
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-05-25 22:13:47 -04:00
liubo 2fc1b6f0d0 tracing: Add __print_symbolic_u64 to avoid warnings on 32bit machine
Filesystem, like Btrfs, has some "ULL" macros, and when these macros are passed
to tracepoints'__print_symbolic(), there will be 64->32 truncate WARNINGS during
compiling on 32bit box.

Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Link: http://lkml.kernel.org/r/4DACE6E0.7000507@cn.fujitsu.com
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-05-25 22:13:44 -04:00
Uwe Kleine-König 3f397c2144 gpio: add trace events for setting direction and value
This patch allows to trace gpio operations using ftrace

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-05-20 00:40:19 -06:00
Linus Torvalds eb04f2f04e Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (78 commits)
  Revert "rcu: Decrease memory-barrier usage based on semi-formal proof"
  net,rcu: convert call_rcu(prl_entry_destroy_rcu) to kfree
  batman,rcu: convert call_rcu(softif_neigh_free_rcu) to kfree_rcu
  batman,rcu: convert call_rcu(neigh_node_free_rcu) to kfree()
  batman,rcu: convert call_rcu(gw_node_free_rcu) to kfree_rcu
  net,rcu: convert call_rcu(kfree_tid_tx) to kfree_rcu()
  net,rcu: convert call_rcu(xt_osf_finger_free_rcu) to kfree_rcu()
  net/mac80211,rcu: convert call_rcu(work_free_rcu) to kfree_rcu()
  net,rcu: convert call_rcu(wq_free_rcu) to kfree_rcu()
  net,rcu: convert call_rcu(phonet_device_rcu_free) to kfree_rcu()
  perf,rcu: convert call_rcu(swevent_hlist_release_rcu) to kfree_rcu()
  perf,rcu: convert call_rcu(free_ctx) to kfree_rcu()
  net,rcu: convert call_rcu(__nf_ct_ext_free_rcu) to kfree_rcu()
  net,rcu: convert call_rcu(net_generic_release) to kfree_rcu()
  net,rcu: convert call_rcu(netlbl_unlhsh_free_addr6) to kfree_rcu()
  net,rcu: convert call_rcu(netlbl_unlhsh_free_addr4) to kfree_rcu()
  security,rcu: convert call_rcu(sel_netif_free) to kfree_rcu()
  net,rcu: convert call_rcu(xps_dev_maps_release) to kfree_rcu()
  net,rcu: convert call_rcu(xps_map_release) to kfree_rcu()
  net,rcu: convert call_rcu(rps_map_release) to kfree_rcu()
  ...
2011-05-19 18:14:34 -07:00
Mel Gorman 1d929b7a84 mm: tracing: add missing GFP flags to tracing
include/linux/gfp.h and include/trace/events/gfpflags.h are out of sync.
When tracing is enabled, certain flags are not recognised and the text
output is less useful as a result.  Add the missing flags.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-11 18:50:45 -07:00
Paul E. McKenney a26ac2455f rcu: move TREE_RCU from softirq to kthread
If RCU priority boosting is to be meaningful, callback invocation must
be boosted in addition to preempted RCU readers.  Otherwise, in presence
of CPU real-time threads, the grace period ends, but the callbacks don't
get invoked.  If the callbacks don't get invoked, the associated memory
doesn't get freed, so the system is still subject to OOM.

But it is not reasonable to priority-boost RCU_SOFTIRQ, so this commit
moves the callback invocations to a kthread, which can be boosted easily.

Also add comments and properly synchronized all accesses to
rcu_cpu_kthread_task, as suggested by Lai Jiangshan.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-05-05 23:16:54 -07:00
Jens Axboe 49cac01e1f block: make unplug timer trace event correspond to the schedule() unplug
It's a pretty close match to what we had before - the timer triggering
would mean that nobody unplugged the plug in due time, in the new
scheme this matches very closely what the schedule() unplug now is.
It's essentially the difference between an explicit unplug (IO unplug)
or an implicit unplug (timer unplug, we scheduled with pending IO
queued).

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-04-16 13:51:05 +02:00
Jens Axboe 94b5eb28b4 block: fixup block IO unplug trace call
It was removed with the on-stack plugging, readd it and track the
depth of requests added when flushing the plug.

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-04-12 10:12:19 +02:00
Jens Axboe d9c9783317 block: remove block_unplug_timer() trace point
We no longer have an unplug timer running, so no point in keeping
the trace point.

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-04-12 10:06:33 +02:00
Linus Torvalds 212a17ab87 Merge branch 'for-linus-unmerged' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
* 'for-linus-unmerged' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: (45 commits)
  Btrfs: fix __btrfs_map_block on 32 bit machines
  btrfs: fix possible deadlock by clearing __GFP_FS flag
  btrfs: check link counter overflow in link(2)
  btrfs: don't mess with i_nlink of unlocked inode in rename()
  Btrfs: check return value of btrfs_alloc_path()
  Btrfs: fix OOPS of empty filesystem after balance
  Btrfs: fix memory leak of empty filesystem after balance
  Btrfs: fix return value of setflags ioctl
  Btrfs: fix uncheck memory allocations
  btrfs: make inode ref log recovery faster
  Btrfs: add btrfs_trim_fs() to handle FITRIM
  Btrfs: adjust btrfs_discard_extent() return errors and trimmed bytes
  Btrfs: make btrfs_map_block() return entire free extent for each device of RAID0/1/10/DUP
  Btrfs: make update_reserved_bytes() public
  btrfs: return EXDEV when linking from different subvolumes
  Btrfs: Per file/directory controls for COW and compression
  Btrfs: add datacow flag in inode flag
  btrfs: use GFP_NOFS instead of GFP_KERNEL
  Btrfs: check return value of read_tree_block()
  btrfs: properly access unaligned checksum buffer
  ...

Fix up trivial conflicts in fs/btrfs/volumes.c due to plug removal in
the block layer.
2011-03-28 15:31:05 -07:00
liubo 1abe9b8a13 Btrfs: add initial tracepoint support for btrfs
Tracepoints can provide insight into why btrfs hits bugs and be greatly
helpful for debugging, e.g
              dd-7822  [000]  2121.641088: btrfs_inode_request: root = 5(FS_TREE), gen = 4, ino = 256, blocks = 8, disk_i_size = 0, last_trans = 8, logged_trans = 0
              dd-7822  [000]  2121.641100: btrfs_inode_new: root = 5(FS_TREE), gen = 8, ino = 257, blocks = 0, disk_i_size = 0, last_trans = 0, logged_trans = 0
 btrfs-transacti-7804  [001]  2146.935420: btrfs_cow_block: root = 2(EXTENT_TREE), refs = 2, orig_buf = 29368320 (orig_level = 0), cow_buf = 29388800 (cow_level = 0)
 btrfs-transacti-7804  [001]  2146.935473: btrfs_cow_block: root = 1(ROOT_TREE), refs = 2, orig_buf = 29364224 (orig_level = 0), cow_buf = 29392896 (cow_level = 0)
 btrfs-transacti-7804  [001]  2146.972221: btrfs_transaction_commit: root = 1(ROOT_TREE), gen = 8
   flush-btrfs-2-7821  [001]  2155.824210: btrfs_chunk_alloc: root = 3(CHUNK_TREE), offset = 1103101952, size = 1073741824, num_stripes = 1, sub_stripes = 0, type = DATA
   flush-btrfs-2-7821  [001]  2155.824241: btrfs_cow_block: root = 2(EXTENT_TREE), refs = 2, orig_buf = 29388800 (orig_level = 0), cow_buf = 29396992 (cow_level = 0)
   flush-btrfs-2-7821  [001]  2155.824255: btrfs_cow_block: root = 4(DEV_TREE), refs = 2, orig_buf = 29372416 (orig_level = 0), cow_buf = 29401088 (cow_level = 0)
   flush-btrfs-2-7821  [000]  2155.824329: btrfs_cow_block: root = 3(CHUNK_TREE), refs = 2, orig_buf = 20971520 (orig_level = 0), cow_buf = 20975616 (cow_level = 0)
 btrfs-endio-wri-7800  [001]  2155.898019: btrfs_cow_block: root = 5(FS_TREE), refs = 2, orig_buf = 29384704 (orig_level = 0), cow_buf = 29405184 (cow_level = 0)
 btrfs-endio-wri-7800  [001]  2155.898043: btrfs_cow_block: root = 7(CSUM_TREE), refs = 2, orig_buf = 29376512 (orig_level = 0), cow_buf = 29409280 (cow_level = 0)

Here is what I have added:

1) ordere_extent:
        btrfs_ordered_extent_add
        btrfs_ordered_extent_remove
        btrfs_ordered_extent_start
        btrfs_ordered_extent_put

These provide critical information to understand how ordered_extents are
updated.

2) extent_map:
        btrfs_get_extent

extent_map is used in both read and write cases, and it is useful for tracking
how btrfs specific IO is running.

3) writepage:
        __extent_writepage
        btrfs_writepage_end_io_hook

Pages are cirtical resourses and produce a lot of corner cases during writeback,
so it is valuable to know how page is written to disk.

4) inode:
        btrfs_inode_new
        btrfs_inode_request
        btrfs_inode_evict

These can show where and when a inode is created, when a inode is evicted.

5) sync:
        btrfs_sync_file
        btrfs_sync_fs

These show sync arguments.

6) transaction:
        btrfs_transaction_commit

In transaction based filesystem, it will be useful to know the generation and
who does commit.

7) back reference and cow:
	btrfs_delayed_tree_ref
	btrfs_delayed_data_ref
	btrfs_delayed_ref_head
	btrfs_cow_block

Btrfs natively supports back references, these tracepoints are helpful on
understanding btrfs's COW mechanism.

8) chunk:
	btrfs_chunk_alloc
	btrfs_chunk_free

Chunk is a link between physical offset and logical offset, and stands for space
infomation in btrfs, and these are helpful on tracing space things.

9) reserved_extent:
	btrfs_reserved_extent_alloc
	btrfs_reserved_extent_free

These can show how btrfs uses its space.

Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-03-28 05:37:33 -04:00
Linus Torvalds ae005cbed1 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (43 commits)
  ext4: fix a BUG in mb_mark_used during trim.
  ext4: unused variables cleanup in fs/ext4/extents.c
  ext4: remove redundant set_buffer_mapped() in ext4_da_get_block_prep()
  ext4: add more tracepoints and use dev_t in the trace buffer
  ext4: don't kfree uninitialized s_group_info members
  ext4: add missing space in printk's in __ext4_grp_locked_error()
  ext4: add FITRIM to compat_ioctl.
  ext4: handle errors in ext4_clear_blocks()
  ext4: unify the ext4_handle_release_buffer() api
  ext4: handle errors in ext4_rename
  jbd2: add COW fields to struct jbd2_journal_handle
  jbd2: add the b_cow_tid field to journal_head struct
  ext4: Initialize fsync transaction ids in ext4_new_inode()
  ext4: Use single thread to perform DIO unwritten convertion
  ext4: optimize ext4_bio_write_page() when no extent conversion is needed
  ext4: skip orphan cleanup if fs has unknown ROCOMPAT features
  ext4: use the nblocks arg to ext4_truncate_restart_trans()
  ext4: fix missing iput of root inode for some mount error paths
  ext4: make FIEMAP and delayed allocation play well together
  ext4: suppress verbose debugging information if malloc-debug is off
  ...

Fi up conflicts in fs/ext4/super.c due to workqueue changes
2011-03-25 09:57:41 -07:00
Jiaying Zhang 0562e0bad4 ext4: add more tracepoints and use dev_t in the trace buffer
- Add more ext4 tracepoints.
- Change ext4 tracepoints to use dev_t field with MAJOR/MINOR macros
so that we can save 4 bytes in the ring buffer on some platforms.
- Add sync_mode to ext4_da_writepages, ext4_da_write_pages, and
ext4_da_writepages_result tracepoints. Also remove for_reclaim
field from ext4_da_writepages since it is usually not very useful.

Signed-off-by: Jiaying Zhang <jiayingz@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-03-21 21:38:05 -04:00
Linus Torvalds d3e458d781 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6: (308 commits)
  ALSA: sound/pci/asihpi: check adapter index in hpi_ioctl
  ALSA: aloop - Fix possible IRQ lock inversion
  ALSA: sound/core: merge list_del()/list_add_tail() to list_move_tail()
  ALSA: ctxfi - use list_move() instead of list_del()/list_add() combination
  ALSA: firewire - msleep needs delay.h
  ALSA: firewire-lib, firewire-speakers: handle packet queueing errors
  ALSA: firewire-lib: allocate DMA buffer separately
  ALSA: firewire-lib: use no-info SYT for packets without SYT sample
  ALSA: add LaCie FireWire Speakers/Griffin FireWave Surround driver
  ALSA: hda - Remove an unused variable in patch_realtek.c
  ALSA: hda - pin-adc-mux-dmic auto-configuration of 92HD8X codecs
  ALSA: hda - fix digital mic selection in mixer on 92HD8X codecs
  ALSA: hda - Move default input-src selection to init part
  ALSA: hda - Initialize special cases for input src in init phase
  ALSA: ctxfi - Clear input settings before initialization
  ALSA: ctxfi - Fix SPDIF status retrieval
  ALSA: ctxfi - Fix incorrect SPDIF status bit mask
  ALSA: ctxfi - Fix microphone boost codes/comments
  ALSA: atiixp - Fix wrong time-out checks during ac-link reset
  ALSA: intel8x0m: append 'm' to "r_intel8x0"
  ...
2011-03-18 10:46:37 -07:00
Linus Torvalds c55d267de2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (170 commits)
  [SCSI] scsi_dh_rdac: Add MD36xxf into device list
  [SCSI] scsi_debug: add consecutive medium errors
  [SCSI] libsas: fix ata list corruption issue
  [SCSI] hpsa: export resettable host attribute
  [SCSI] hpsa: move device attributes to avoid forward declarations
  [SCSI] scsi_debug: Logical Block Provisioning (SBC3r26)
  [SCSI] sd: Logical Block Provisioning update
  [SCSI] Include protection operation in SCSI command trace
  [SCSI] hpsa: fix incorrect PCI IDs and add two new ones (2nd try)
  [SCSI] target: Fix volume size misreporting for volumes > 2TB
  [SCSI] bnx2fc: Broadcom FCoE offload driver
  [SCSI] fcoe: fix broken fcoe interface reset
  [SCSI] fcoe: precedence bug in fcoe_filter_frames()
  [SCSI] libfcoe: Remove stale fcoe-netdev entries
  [SCSI] libfcoe: Move FCOE_MTU definition from fcoe.h to libfcoe.h
  [SCSI] libfc: introduce __fc_fill_fc_hdr that accepts fc_hdr as an argument
  [SCSI] fcoe, libfc: initialize EM anchors list and then update npiv EMs
  [SCSI] Revert "[SCSI] libfc: fix exchange being deleted when the abort itself is timed out"
  [SCSI] libfc: Fixing a memory leak when destroying an interface
  [SCSI] megaraid_sas: Version and Changelog update
  ...

Fix up trivial conflicts due to whitespace differences in
drivers/scsi/libsas/{sas_ata.c,sas_scsi_host.c}
2011-03-17 17:54:40 -07:00
Linus Torvalds f74b944419 Merge branch 'config' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl
* 'config' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl:
  BKL: That's all, folks
  fs/locks.c: Remove stale FIXME left over from BKL conversion
  ipx: remove the BKL
  appletalk: remove the BKL
  x25: remove the BKL
  ufs: remove the BKL
  hpfs: remove the BKL
  drivers: remove extraneous includes of smp_lock.h
  tracing: don't trace the BKL
  adfs: remove the big kernel lock
2011-03-16 17:21:00 -07:00
Takashi Iwai 27b92d4ff2 Merge branch 'topic/asoc' into for-linus 2011-03-16 17:38:41 +01:00
Martin K. Petersen 72f7d322fd [SCSI] Include protection operation in SCSI command trace
When debugging DIF/DIX it is very helpful to be able to see which DIX
operation is associated with the scsi_cmnd. Include the protection op in
the SCSI command trace.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-03-14 18:36:02 -05:00
David Sharp ca9da2dd63 tracing: Fix event alignment: skb:kfree_skb
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David Sharp <dhsharp@google.com>
LKML-Reference: <1291421609-14665-10-git-send-email-dhsharp@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-03-10 10:34:31 -05:00
David Sharp ad440ad66f tracing: Fix event alignment: mce:mce_record
Signed-off-by: David Sharp <dhsharp@google.com>
LKML-Reference: <1291421609-14665-9-git-send-email-dhsharp@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-03-10 10:34:28 -05:00
David Sharp b5e3008e48 tracing: Fix event alignment: module:module_request
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: David Sharp <dhsharp@google.com>
LKML-Reference: <1291421609-14665-7-git-send-email-dhsharp@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-03-10 10:34:20 -05:00
Tao Ma 2d3a8497f8 blktrace: Remove blk_fill_rwbs_rq.
If we enable trace events to trace block actions, We use
blk_fill_rwbs_rq to analyze the corresponding actions
in request's cmd_flags, but we only choose the minor 2 bits
from it, so most of other flags(e.g, REQ_SYNC) are missing.
For example, with a sync write we get:
write_test-2409  [001]   160.013869: block_rq_insert: 3,64 W 0 () 258135 + =
8 [write_test]

Since now we have integrated the flags of both bio and request,
it is safe to pass rq->cmd_flags directly to blk_fill_rwbs and
blk_fill_rwbs_rq isn't needed any more.

With this patch, after a sync write we get:
write_test-2417  [000]   226.603878: block_rq_insert: 3,64 WS 0 () 258135 +=
 8 [write_test]

Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-03 10:53:20 -05:00
Arnd Bergmann f51b452bed tracing: don't trace the BKL
No reason to trace it when the last user is gone.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
2011-03-02 00:02:39 +01:00
Steven Rostedt e4a9ea5ee7 tracing: Replace trace_event struct array with pointer array
Currently the trace_event structures are placed in the _ftrace_events
section, and at link time, the linker makes one large array of all
the trace_event structures. On boot up, this array is read (much like
the initcall sections) and the events are processed.

The problem is that there is no guarantee that gcc will place complex
structures nicely together in an array format. Two structures in the
same file may be placed awkwardly, because gcc has no clue that they
are suppose to be in an array.

A hack was used previous to force the alignment to 4, to pack the
structures together. But this caused alignment issues with other
architectures (sparc).

Instead of packing the structures into an array, the structures' addresses
are now put into the _ftrace_event section. As pointers are always the
natural alignment, gcc should always pack them tightly together
(otherwise initcall, extable, etc would also fail).

By having the pointers to the structures in the section, we can still
iterate the trace_events without causing unnecessary alignment problems
with other architectures, or depending on the current behaviour of
gcc that will likely change in the future just to tick us kernel developers
off a little more.

The _ftrace_event section is also moved into the .init.data section
as it is now only needed at boot up.

Suggested-by: David Miller <davem@davemloft.net>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-02-02 21:37:13 -05:00
Dimitris Papastamos c358e640a6 ASoC: soc-cache: Add trace event for snd_soc_cache_sync()
This patch makes it easy to see when the syncing process begins and
ends.  You can also enable the snd_soc_reg_write tracepoint to see
which registers are being synced.

Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-01-21 18:30:51 +00:00
Linus Torvalds f9ee7f60d6 Merge branches 'core-fixes-for-linus', 'x86-fixes-for-linus', 'timers-fixes-for-linus' and 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  rcu: avoid pointless blocked-task warnings
  rcu: demote SRCU_SYNCHRONIZE_DELAY from kernel-parameter status
  rtmutex: Fix comment about why new_owner can be NULL in wake_futex_pi()

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, olpc: Add missing Kconfig dependencies
  x86, mrst: Set correct APB timer IRQ affinity for secondary cpu
  x86: tsc: Fix calibration refinement conditionals to avoid divide by zero
  x86, ia64, acpi: Clean up x86-ism in drivers/acpi/numa.c

* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  timekeeping: Make local variables static
  time: Rename misnamed minsec argument of clocks_calc_mult_shift()

* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  tracing: Remove syscall_exit_fields
  tracing: Only process module tracepoints once
  perf record: Add "nodelay" mode, disabled by default
  perf sched: Fix list of events, dropping unsupported ':r' modifier
  Revert "perf tools: Emit clearer message for sys_perf_event_open ENOENT return"
  perf top: Fix annotate segv
  perf evsel: Fix order of event list deletion
2011-01-15 12:45:00 -08:00
Steven Rostedt c94fbe1d9e tracing: Only process module tracepoints once
The commit:

 9f987b3141f086de27832514aad9f50a53f754
 tracing: Include module.h in define_trace.h

only solved half the problem. If the trace/events/module.h header is
included at the time of define_trace.h (or in ftrace.h within it),
the module.h TRACE_SYSTEM will override the current TRACE_SYSTEM
macro.

Since define_trace.h is included when CREATE_TRACE_POINTS is set,
and the first thing it does is to #undef CREATE_TRACE_POINTS,
by placing the module.h TRACE_SYSTEM inside a
 #ifdef CREATE_TRACE_POINTS
we can prevent it from overriding the TRACE_SYSTEM that is
being processed, and still process the module.h tracepoints
when the module code defines CREATE_TRACE_POINTS and includes
the trace/events/module.h header.

As with commit 9f987b3141, this is only an issue if module.h
is not included before the trace/events/<event>.h file is
included, which (luckily) has not happened yet.

Reported-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-01-14 11:25:58 -05:00
Mel Gorman f3a310bc4e mm: vmscan: rename lumpy_mode to reclaim_mode
With compaction being used instead of lumpy reclaim, the name lumpy_mode
and associated variables is a bit misleading.  Rename lumpy_mode to
reclaim_mode which is a better fit.  There is no functional change.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:34 -08:00
Mel Gorman ee64fc9354 mm: vmscan: convert lumpy_mode into a bitmask
Currently lumpy_mode is an enum and determines if lumpy reclaim is off,
syncronous or asyncronous.  In preparation for using compaction instead of
lumpy reclaim, this patch converts the flags into a bitmap.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:33 -08:00
Mel Gorman b7aba6984d mm: compaction: add trace events for memory compaction activity
In preparation for a patches promoting the use of memory compaction over
lumpy reclaim, this patch adds trace points for memory compaction
activity.  Using them, we can monitor the scanning activity of the
migration and free page scanners as well as the number and success rates
of pages passed to page migration.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:33 -08:00
Wu Fengguang 71927e84e0 writeback: trace wakeup event for background writeback
This tracks when balance_dirty_pages() tries to wakeup the flusher thread
for background writeback (if it was not started already).

Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jan Engelhardt <jengelh@medozas.de>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:32 -08:00
Linus Torvalds 275220f0fc Merge branch 'for-2.6.38/core' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.38/core' of git://git.kernel.dk/linux-2.6-block: (43 commits)
  block: ensure that completion error gets properly traced
  blktrace: add missing probe argument to block_bio_complete
  block cfq: don't use atomic_t for cfq_group
  block cfq: don't use atomic_t for cfq_queue
  block: trace event block fix unassigned field
  block: add internal hd part table references
  block: fix accounting bug on cross partition merges
  kref: add kref_test_and_get
  bio-integrity: mark kintegrityd_wq highpri and CPU intensive
  block: make kblockd_workqueue smarter
  Revert "sd: implement sd_check_events()"
  block: Clean up exit_io_context() source code.
  Fix compile warnings due to missing removal of a 'ret' variable
  fs/block: type signature of major_to_index(int) to major_to_index(unsigned)
  block: convert !IS_ERR(p) && p to !IS_ERR_NOR_NULL(p)
  cfq-iosched: don't check cfqg in choose_service_tree()
  fs/splice: Pull buf->ops->confirm() from splice_from_pipe actors
  cdrom: export cdrom_check_events()
  sd: implement sd_check_events()
  sr: implement sr_check_events()
  ...
2011-01-13 10:45:01 -08:00
Linus Torvalds 66dc918d42 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6: (348 commits)
  ALSA: hda - Fix NULL-derefence with a single mic in STAC auto-mic detection
  ALSA: hda - Add missing NID 0x19 fixup for Sony VAIO
  ALSA: hda - Fix ALC275 enable hardware EQ for SONY VAIO
  ALSA: oxygen: fix Xonar DG input
  ALSA: hda - Fix EAPD on Lenovo NB ALC269 to low
  ALSA: hda - Fix missing EAPD for Acer 4930G
  ALSA: hda: Disable 4/6 channels on some NVIDIA GPUs.
  ALSA: hda - Add static_hdmi_pcm option to HDMI codec parser
  ALSA: hda - Don't refer ELD when unplugged
  ASoC: tpa6130a2: Fix compiler warning
  ASoC: tlv320dac33: Add DAPM selection for LOM invert
  ASoC: DMIC codec: Adding a generic DMIC codec
  ALSA: snd-usb-us122l: Fix missing NULL checks
  ALSA: snd-usb-us122l: Fix MIDI output
  ASoC: soc-cache: Fix invalid memory access during snd_soc_lzo_cache_sync()
  ASoC: Fix section mismatch in wm8995.c
  ALSA: oxygen: add S/PDIF source selection for Claro cards
  ALSA: oxygen: fix CD/MIDI for X-Meridian (2G)
  ASoC: fix migor audio build
  ALSA: include delay.h for msleep in Xonar DG support
  ...
2011-01-13 10:32:54 -08:00
Linus Torvalds 1896a1346a Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lrg/voltage-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lrg/voltage-2.6: (45 commits)
  regulator: missing index in PTR_ERR() in isl6271a_probe()
  regulator: Assign return value of mc13xxx_reg_rmw to ret
  regulator: Add initial per-regulator debugfs support
  regulator: Make regulator_has_full_constraints a bool
  regulator: Clean up logging a bit
  regulator: Optimise out noop voltage changes
  regulator: Add API to re-apply voltage to hardware
  regulator: Staticise non-exported functions in mc13892
  regulator: Only notify voltage changes when they succeed
  regulator: Provide a selector based set_voltage_sel() operation
  regulator: Factor out voltage set operation into a separate function
  regulator: Convert WM8994 to use get_voltage_sel()
  regulator: Convert WM835x to use get_voltage_sel()
  regulator: Allow modular build of mc13xxx-core
  regulator: support PMIC mc13892
  make mc13783 regulator code generic
  Change the register name definitions for mc13783
  mach-ux500: Updated and connected ab8500 regulator board configuration
  regulators: Removed macros for initialization of ab8500 regulators
  regulators: Added verbose debug messages to ab8500 regulators
  ...
2011-01-13 10:24:07 -08:00
Linus Torvalds 55065bc527 Merge branch 'kvm-updates/2.6.38' of git://git.kernel.org/pub/scm/virt/kvm/kvm
* 'kvm-updates/2.6.38' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (142 commits)
  KVM: Initialize fpu state in preemptible context
  KVM: VMX: when entering real mode align segment base to 16 bytes
  KVM: MMU: handle 'map_writable' in set_spte() function
  KVM: MMU: audit: allow audit more guests at the same time
  KVM: Fetch guest cr3 from hardware on demand
  KVM: Replace reads of vcpu->arch.cr3 by an accessor
  KVM: MMU: only write protect mappings at pagetable level
  KVM: VMX: Correct asm constraint in vmcs_load()/vmcs_clear()
  KVM: MMU: Initialize base_role for tdp mmus
  KVM: VMX: Optimize atomic EFER load
  KVM: VMX: Add definitions for more vm entry/exit control bits
  KVM: SVM: copy instruction bytes from VMCB
  KVM: SVM: implement enhanced INVLPG intercept
  KVM: SVM: enhance mov DR intercept handler
  KVM: SVM: enhance MOV CR intercept handler
  KVM: SVM: add new SVM feature bit names
  KVM: cleanup emulate_instruction
  KVM: move complete_insn_gp() into x86.c
  KVM: x86: fix CR8 handling
  KVM guest: Fix kvm clock initialization when it's configured out
  ...
2011-01-13 10:14:24 -08:00
Mark Brown 02fa3ec01a regulator: Add basic trace facilities
Provide some basic trace facilities to the regulator API. We generate
events on regulator enable, disable and voltage setting over the actual
hardware operations (which are assumed to be the expensive ones which
require interaction with the actual device). This is intended to facilitate
debug of the performance and behaviour with consumers allowing unified
traces to be generated including the regulator operations within the
context of the other components of the system.

For enable we log the explicit delay for the voltage ramp separately to
the interaction with the hardware to highlight the time consumed in I/O.
We should add a similar delay for voltage changes, though there the
relatively small magnitude of the changes in the context of the I/O
costs makes it much less critical for most regulators.

Only hardware interactions are currently traced as the primary focus is
on the performance and synchronisation of actual hardware interactions.
Additional tracepoints for debugging of the logical operations can be
added later if required.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-01-12 14:33:00 +00:00
Xiao Guangrong 0730388b97 KVM: cleanup async_pf tracepoints
Use 'DECLARE_EVENT_CLASS' to cleanup async_pf tracepoints

Acked-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-01-12 11:28:57 +02:00
Xiao Guangrong c9b263d2be KVM: fix tracing kvm_try_async_get_page
Tracing 'async' and *pfn is useless, since 'async' is always true,
and '*pfn' is always "fault_pfn'

We can trace 'gva' and 'gfn' instead, it can help us to see the
life-cycle of an async_pf

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-01-12 11:28:56 +02:00
Gleb Natapov 64be500706 KVM: x86: trace "exit to userspace" event
Add tracepoint for userspace exit.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-01-12 11:28:44 +02:00
Gleb Natapov 7c90705bf2 KVM: Inject asynchronous page fault into a PV guest if page is swapped out.
Send async page fault to a PV guest if it accesses swapped out memory.
Guest will choose another task to run upon receiving the fault.

Allow async page fault injection only when guest is in user mode since
otherwise guest may be in non-sleepable context and will not be able
to reschedule.

Vcpu will be halted if guest will fault on the same page again or if
vcpu executes kernel code.

Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-01-12 11:23:17 +02:00
Gleb Natapov af585b921e KVM: Halt vcpu if page it tries to access is swapped out
If a guest accesses swapped out memory do not swap it in from vcpu thread
context. Schedule work to do swapping and put vcpu into halted state
instead.

Interrupts will still be delivered to the guest and if interrupt will
cause reschedule guest will continue to run another task.

[avi: remove call to get_user_pages_noio(), nacked by Linus; this
      makes everything synchrnous again]

Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-01-12 11:21:39 +02:00
Mathieu Desnoyers 881fe4bdcd tracing: remove duplicate null-pointer check in skb tracepoint
The check for NULL skb in the kfree_skb trace event is a duplicate from the
check already done in its only caller, kfree_skb(). Remove this duplicate check.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
LKML-Reference: <20110106175319.GA30610@Krystal>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: David S. Miller <davem@davemloft.net>
CC: Steven Rostedt <rostedt@goodmis.org>
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: Ingo Molnar <mingo@elte.hu>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Zhaolei <zhaolei@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-01-07 20:55:42 -05:00
Steven Rostedt 3a9f987b31 tracing: Include module.h in define_trace.h
While doing some developing, Peter Zijlstra and I have found
that if a CREATE_TRACE_POINTS include is done before module.h
is included, it can break the build.

We have been lucky so far that this has not broke the build
since module.h is included in almost everything.

Reported-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-01-07 15:44:56 -05:00
Jeff Moyer b7908c1035 block: trace event block fix unassigned field
The "error" field in block_bio_complete is not assigned, leaving the memory area
uninitialized (keeping garbage data). Pass an additional tracepoint argument to
this event to initialize this field.

Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
CC: Steven Rostedt <rostedt@goodmis.org>
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: Ingo Molnar <mingo@elte.hu>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Li Zefan <lizf@cn.fujitsu.com>
CC: Alan.Brunelle@hp.com
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-01-07 08:43:55 +01:00
Thomas Renninger 25e41933b5 perf: Clean up power events by introducing new, more generic ones
Add these new power trace events:

 power:cpu_idle
 power:cpu_frequency
 power:machine_suspend

The old C-state/idle accounting events:
  power:power_start
  power:power_end

Have now a replacement (but we are still keeping the old
tracepoints for compatibility):

  power:cpu_idle

and
  power:power_frequency

is replaced with:
  power:cpu_frequency

power:machine_suspend is newly introduced.

Jean Pihet has a patch integrated into the generic layer
(kernel/power/suspend.c) which will make use of it.

the type= field got removed from both, it was never
used and the type is differed by the event type itself.

perf timechart userspace tool gets adjusted in a separate patch.

Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Jean Pihet <jean.pihet@newoldbits.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: rjw@sisk.pl
LKML-Reference: <1294073445-14812-3-git-send-email-trenn@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <1290072314-31155-2-git-send-email-trenn@suse.de>
2011-01-04 08:16:54 +01:00
Mark Brown 3028eb8c51 ASoC: Add trace events for jack detection
As jack detection can trigger DAPM and the latency in debouncing can create
confusing windows in operation provide some trace events which will hopefully
help in diagnostics. The soc-jack core traces all reports that it gets and
the resulting notifications to upper layers. An event for jack IRQs is also
provided for instrumentation of debounce, and used in the GPIO jack code.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-12-06 14:13:42 +00:00
Steven Rostedt 287050d390 tracing: Add TRACE_EVENT_CONDITIONAL()
There are instances in the kernel that we only want to trace
a tracepoint when a certain condition is set. But we do not
want to test for that condition in the core kernel.
If we test for that condition before calling the tracepoin, then
we will be performing that test even when tracing is not enabled.
This is 99.99% of the time.

We currently can just filter out on that condition, but that happens
after we write to the trace buffer. We just wasted time writing to
the ring buffer for an event we never cared about.

This patch adds:

   TRACE_EVENT_CONDITION() and DEFINE_EVENT_CONDITION()

These have a new TP_CONDITION() argument that comes right after
the TP_ARGS().  This condition can use the parameters of TP_ARGS()
in the TRACE_EVENT() to determine if the tracepoint should be traced
or not. The TP_CONDITION() will be placed in a if (cond) trace;

For example, for the tracepoint sched_wakeup, it is useless to
trace a wakeup event where the caller never actually wakes
anything up (where success == 0). So adding:

	TP_CONDITION(success),

which uses the "success" parameter of the wakeup tracepoint
will have it only trace when we have successfully woken up a
task.

Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-12-03 10:45:34 -05:00
Steven Rostedt 0429578016 tracing/events: Show real number in array fields
Currently we have in something like the sched_switch event:

  field:char prev_comm[TASK_COMM_LEN];	offset:12;	size:16;	signed:1;

When a userspace tool such as perf tries to parse this, the
TASK_COMM_LEN is meaningless. This is done because the TRACE_EVENT() macro
simply uses a #len to show the string of the length. When the length is
an enum, we get a string that means nothing for tools.

By adding a static buffer and a mutex to protect it, we can store the
string into that buffer with snprintf and show the actual number.
Now we get:

  field:char prev_comm[16];       offset:12;      size:16;        signed:1;

Something much more useful.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-11-19 10:18:47 -05:00
Mark Brown 9e18e1869f Merge branch 'next-samsung-asoc' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung into for-2.6.38 2010-11-19 11:49:35 +00:00
Ingo Molnar ae51ce9061 Merge branch 'perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into perf/core 2010-11-18 20:07:12 +01:00
Frederic Weisbecker 53cf810b19 tracing: Allow syscall trace events for non privileged users
As for the raw syscalls events, individual syscall events won't
leak system wide information on task bound tracing. Allow non
privileged users to use them in such workflow.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Jason Baron <jbaron@redhat.com>
2010-11-18 14:37:44 +01:00
Frederic Weisbecker fe5542030d tracing: Allow raw syscall trace events for non privileged users
This allows non privileged users to use the raw syscall trace events
for task bound tracing in perf.

It is safe because raw syscall trace events don't leak system wide
informations.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Jason Baron <jbaron@redhat.com>
2010-11-18 14:37:43 +01:00
Frederic Weisbecker 1ed0c59711 tracing: New macro to set up initial event flags value
This introduces the new TRACE_EVENT_FLAGS() macro in order
to set up initial event flags value.

This macro must simply follow the definition of a trace event
and take the event name and the flag value as parameters:

TRACE_EVENT(my_event, .....
....
);

TRACE_EVENT_FLAGS(my_event, 1)

This will set up 1 as the initial my_event->flags value.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Jason Baron <jbaron@redhat.com>
2010-11-18 14:37:42 +01:00
Mike Snitzer d07335e51d block: Rename "block_remap" tracepoint to "block_bio_remap" to clarify the event.
Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-11-16 12:53:39 +01:00
Mark Brown 84e909303d ASoC: Add DAPM trace events
Trace events for DAPM allow us to monitor the performance and behaviour
of DAPM with logging which can be built into the kernel permanantly, is
more suited to automated analysis and display and less likely to suffer
interference from other logging activity.

Currently trace events are generated for:

- Start and stop of DAPM processing
- Start and stop of bias level changes
- Power decisions for widgets
- Widget event execution start and stop

giving some view as to what is happening and where latencies occur.

Actual changes in widget power can be seen via the register write trace in
soc-core.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-11-11 14:54:31 +00:00
Mark Brown a8b1d34f3e ASoC: Add trace events for ASoC register read/write
The trace subsystem provides a convenient way of instrumenting the kernel
which can be left on all the time with extremely low impact on the system
unlike prints to the kernel log which can be very spammy. Begin adding
support for instrumenting ASoC via this interface by adding trace for the
register access primitives.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-11-11 14:54:26 +00:00
Theodore Ts'o 7ff9c073dd ext4: Add new ext4 inode tracepoints
Add ext4_evict_inode, ext4_drop_inode, ext4_mark_inode_dirty, and
ext4_begin_ordered_truncate()

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-11-08 13:51:33 -05:00
Theodore Ts'o a107e5a3a4 Merge branch 'next' into upstream-merge
Conflicts:
	fs/ext4/inode.c
	fs/ext4/mballoc.c
	include/trace/events/ext4.h
2010-10-27 23:44:47 -04:00
Theodore Ts'o a269029d0e ext4,jbd2: convert tracepoints to use major/minor numbers
Unfortunately perf can't deal with anything other than direct structure
accesses in the TP_printk() section.  It will drop dead when it sees
jbd2_dev_to_name() in the "print fmt" section of the tracepoint.

Addresses-Google-Bug: 3138508

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-27 22:08:50 -04:00
Linus Torvalds a042e26137 Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (50 commits)
  perf python scripting: Add futex-contention script
  perf python scripting: Fixup cut'n'paste error in sctop script
  perf scripting: Shut up 'perf record' final status
  perf record: Remove newline character from perror() argument
  perf python scripting: Support fedora 11 (audit 1.7.17)
  perf python scripting: Improve the syscalls-by-pid script
  perf python scripting: print the syscall name on sctop
  perf python scripting: Improve the syscalls-counts script
  perf python scripting: Improve the failed-syscalls-by-pid script
  kprobes: Remove redundant text_mutex lock in optimize
  x86/oprofile: Fix uninitialized variable use in debug printk
  tracing: Fix 'faild' -> 'failed' typo
  perf probe: Fix format specified for Dwarf_Off parameter
  perf trace: Fix detection of script extension
  perf trace: Use $PERF_EXEC_PATH in canned report scripts
  perf tools: Document event modifiers
  perf tools: Remove direct slang.h include
  perf_events: Fix for transaction recovery in group_sched_in()
  perf_events: Revert: Fix transaction recovery in group_sched_in()
  perf, x86: Use NUMA aware allocations for PEBS/BTS/DS allocations
  ...
2010-10-27 18:48:00 -07:00
Eric Sandeen 3e1e5f5016 ext4: don't use ext4_allocation_contexts for tracing
Many tracepoints were populating an ext4_allocation_context
to pass in, but this requires a slab allocation even when
tracepoints are off.  In fact, 4 of 5 of these allocations
were only for tracing.  In addition, we were only using a
small fraction of the 144 bytes of this structure for this
purpose.

We can do away with all these alloc/frees of the ac and
simply pass in the bits we care about, instead.

I tested this by turning on tracing and running through
xfstests on x86_64.  I did not actually do anything with
the trace output, however.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-27 21:30:07 -04:00
Eric Sandeen 4d5476164a ext4: fix oops in trace_ext4_mb_release_group_pa
Our QA reported an oops in the ext4_mb_release_group_pa tracing,
and Josef Bacik pointed out that it was because we may have a
non-null but uninitialized ac_inode in the allocation context.

I can reproduce it when running xfstests with ext4 tracepoints on, 
on a CONFIG_SLAB_DEBUG kernel.

We call trace_ext4_mb_release_group_pa from 2 places, 
ext4_mb_discard_group_preallocations and 
ext4_mb_discard_lg_preallocations

In both cases we allocate an ac as a container just for tracing (!)
and never fill in the ac_inode.  There's no reason to be assigning,
testing, or printing it as far as I can see, so just remove it from
the tracepoint.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-27 21:30:07 -04:00
Wen Congyang b853fd3648 ext4: avoid null dereference in trace_ext4_mballoc_discard
ac->inode is set to null in function ext4_mb_release_group_pa(),
and then trace_ext4_mballoc_discard(ac) is called, the kernel
will panic.

BUG: unable to handle kernel NULL pointer dereference at 000000a4
IP: [<f87e1714>] ftrace_raw_event_ext4__mballoc+0x54/0xc0 [ext4]
*pdpt = 0000000000abd001 *pde = 0000000000000000
Oops: 0000 [#1] SMP

Pid: 550, comm: flush-8:16 Not tainted 2.6.36-rc1 #1 SE7320EP2/Altos G530
EIP: 0060:[<f87e1714>] EFLAGS: 00010206 CPU: 1
EIP is at ftrace_raw_event_ext4__mballoc+0x54/0xc0 [ext4]
EAX: f32ac840 EBX: f3f1cf88 ECX: f32ac840 EDX: 00000000
ESI: f32ac83c EDI: f880b9d8 EBP: 00000000 ESP: f4b77ae4
 DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
Process flush-8:16 (pid: 550, ti=f4b76000 task=f613e540 task.ti=f4b76000)
Call Trace:
 [<f87f5ac1>] ? ext4_mb_release_group_pa+0x121/0x150 [ext4]
 [<f87f8356>] ? ext4_mb_discard_group_preallocations+0x336/0x400 [ext4]
 [<f87fb7f1>] ? ext4_mb_new_blocks+0x3d1/0x4f0 [ext4]
 [<c05a6c5b>] ? __make_request+0x10b/0x440
 [<f87f1fb4>] ? ext4_ext_map_blocks+0x1334/0x1980 [ext4]
 [<c04ac78a>] ? rb_reserve_next_event+0xaa/0x3b0
 [<f87d18d6>] ? ext4_map_blocks+0xd6/0x1d0 [ext4]
 [<f87d2da7>] ? mpage_da_map_blocks+0xc7/0x8a0 [ext4]
 [<c04c8a68>] ? find_get_pages_tag+0x38/0x110
 [<c04d23a5>] ? __pagevec_release+0x15/0x20
 [<f87d3ca5>] ? ext4_da_writepages+0x2b5/0x5d0 [ext4]
 [<c04cfbe0>] ? __writepage+0x0/0x30
 [<c04d0e34>] ? do_writepages+0x14/0x30
 [<c0526600>] ? writeback_single_inode+0xa0/0x240
 [<c0526971>] ? writeback_sb_inodes+0xc1/0x180
 [<c0526ab8>] ? writeback_inodes_wb+0x88/0x140
 [<c0526d7b>] ? wb_writeback+0x20b/0x320
 [<c045aca7>] ? lock_timer_base+0x27/0x50
 [<c0526fe0>] ? wb_do_writeback+0x150/0x190
 [<c05270a8>] ? bdi_writeback_thread+0x88/0x1f0
 [<c043b680>] ? complete+0x40/0x60
 [<c0527020>] ? bdi_writeback_thread+0x0/0x1f0
 [<c0469474>] ? kthread+0x74/0x80
 [<c0469400>] ? kthread+0x0/0x80
 [<c040a23e>] ? kernel_thread_helper+0x6/0x10

Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-27 21:27:12 -04:00
Mel Gorman 0e093d9976 writeback: do not sleep on the congestion queue if there are no congested BDIs or if significant congestion is not being encountered in the current zone
If congestion_wait() is called with no BDI congested, the caller will
sleep for the full timeout and this may be an unnecessary sleep.  This
patch adds a wait_iff_congested() that checks congestion and only sleeps
if a BDI is congested else, it calls cond_resched() to ensure the caller
is not hogging the CPU longer than its quota but otherwise will not sleep.

This is aimed at reducing some of the major desktop stalls reported during
IO.  For example, while kswapd is operating, it calls congestion_wait()
but it could just have been reclaiming clean page cache pages with no
congestion.  Without this patch, it would sleep for a full timeout but
after this patch, it'll just call schedule() if it has been on the CPU too
long.  Similar logic applies to direct reclaimers that are not making
enough progress.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-26 16:52:07 -07:00
KOSAKI Motohiro 7d3579e8e6 vmscan: narrow the scenarios in whcih lumpy reclaim uses synchrounous reclaim
shrink_page_list() can decide to give up reclaiming a page under a
number of conditions such as

  1. trylock_page() failure
  2. page is unevictable
  3. zone reclaim and page is mapped
  4. PageWriteback() is true
  5. page is swapbacked and swap is full
  6. add_to_swap() failure
  7. page is dirty and gfpmask don't have GFP_IO, GFP_FS
  8. page is pinned
  9. IO queue is congested
 10. pageout() start IO, but not finished

With lumpy reclaim, failures result in entering synchronous lumpy reclaim
but this can be unnecessary.  In cases (2), (3), (5), (6), (7) and (8),
there is no point retrying.  This patch causes lumpy reclaim to abort when
it is known it will fail.

Case (9) is more interesting. current behavior is,
  1. start shrink_page_list(async)
  2. found queue_congested()
  3. skip pageout write
  4. still start shrink_page_list(sync)
  5. wait on a lot of pages
  6. again, found queue_congested()
  7. give up pageout write again

So, it's useless time wasting.  However, just skipping page reclaim is
also notgood as x86 allocating a huge page needs 512 pages for example.
It can have more dirty pages than queue congestion threshold (~=128).

After this patch, pageout() behaves as follows;

 - If order > PAGE_ALLOC_COSTLY_ORDER
	Ignore queue congestion always.
 - If order <= PAGE_ALLOC_COSTLY_ORDER
	skip write page and disable lumpy reclaim.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-26 16:52:07 -07:00
Mel Gorman 52bb919866 writeback: account for time spent congestion_waited
There is strong evidence to indicate a lot of time is being spent in
congestion_wait(), some of it unnecessarily.  This patch adds a tracepoint
for congestion_wait to record when congestion_wait() was called, how long
the timeout was for and how long it actually slept.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Reviewed-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-26 16:52:07 -07:00
Mel Gorman e11da5b4fd tracing, vmscan: add trace events for LRU list shrinking
There have been numerous reports of stalls that pointed at the problem
being somewhere in the VM.  There are multiple roots to the problems which
means dealing with any of the root problems in isolation is tricky to
justify on their own and they would still need integration testing.  This
patch series puts together two different patch sets which in combination
should tackle some of the root causes of latency problems being reported.

Patch 1 adds a tracepoint for shrink_inactive_list.  For this series, the
most important results is being able to calculate the scanning/reclaim
ratio as a measure of the amount of work being done by page reclaim.

Patch 2 accounts for time spent in congestion_wait.

Patches 3-6 were originally developed by Kosaki Motohiro but reworked for
this series.  It has been noted that lumpy reclaim is far too aggressive
and trashes the system somewhat.  As SLUB uses high-order allocations, a
large cost incurred by lumpy reclaim will be noticeable.  It was also
reported during transparent hugepage support testing that lumpy reclaim
was trashing the system and these patches should mitigate that problem
without disabling lumpy reclaim.

Patch 7 adds wait_iff_congested() and replaces some callers of
congestion_wait().  wait_iff_congested() only sleeps if there is a BDI
that is currently congested.  Patch 8 notes that any BDI being congested
is not necessarily a problem because there could be multiple BDIs of
varying speeds and numberous zones.  It attempts to track when a zone
being reclaimed contains many pages backed by a congested BDI and if so,
reclaimers wait on the congestion queue.

I ran a number of tests with monitoring on X86, X86-64 and PPC64. Each
machine had 3G of RAM and the CPUs were

X86:    Intel P4 2-core
X86-64: AMD Phenom 4-core
PPC64:  PPC970MP

Each used a single disk and the onboard IO controller.  Dirty ratio was
left at 20.  I'm just going to report for X86-64 and PPC64 in a vague
attempt to keep this report short.  Four kernels were tested each based on
v2.6.36-rc4

traceonly-v2r2:     Patches 1 and 2 to instrument vmscan reclaims and congestion_wait
lowlumpy-v2r3:      Patches 1-6 to test if lumpy reclaim is better
waitcongest-v2r3:   Patches 1-7 to only wait on congestion
waitwriteback-v2r4: Patches 1-8 to detect when a zone is congested

nocongest-v1r5: Patches 1-3 for testing wait_iff_congestion
nodirect-v1r5:  Patches 1-10 to disable filesystem writeback for better IO

The tests run were as follows

kernbench
	compile-based benchmark. Smoke test performance

sysbench
	OLTP read-only benchmark. Will be re-run in the future as read-write

micro-mapped-file-stream
	This is a micro-benchmark from Johannes Weiner that accesses a
	large sparse-file through mmap(). It was configured to run in only
	single-CPU mode but can be indicative of how well page reclaim
	identifies suitable pages.

stress-highalloc
	Tries to allocate huge pages under heavy load.

kernbench, iozone and sysbench did not report any performance regression
on any machine.  sysbench did pressure the system lightly and there was
reclaim activity but there were no difference of major interest between
the kernels.

X86-64 micro-mapped-file-stream

                                      traceonly-v2r2           lowlumpy-v2r3        waitcongest-v2r3     waitwriteback-v2r4
pgalloc_dma                       1639.00 (   0.00%)       667.00 (-145.73%)      1167.00 ( -40.45%)       578.00 (-183.56%)
pgalloc_dma32                  2842410.00 (   0.00%)   2842626.00 (   0.01%)   2843043.00 (   0.02%)   2843014.00 (   0.02%)
pgalloc_normal                       0.00 (   0.00%)         0.00 (   0.00%)         0.00 (   0.00%)         0.00 (   0.00%)
pgsteal_dma                        729.00 (   0.00%)        85.00 (-757.65%)       609.00 ( -19.70%)       125.00 (-483.20%)
pgsteal_dma32                  2338721.00 (   0.00%)   2447354.00 (   4.44%)   2429536.00 (   3.74%)   2436772.00 (   4.02%)
pgsteal_normal                       0.00 (   0.00%)         0.00 (   0.00%)         0.00 (   0.00%)         0.00 (   0.00%)
pgscan_kswapd_dma                 1469.00 (   0.00%)       532.00 (-176.13%)      1078.00 ( -36.27%)       220.00 (-567.73%)
pgscan_kswapd_dma32            4597713.00 (   0.00%)   4503597.00 (  -2.09%)   4295673.00 (  -7.03%)   3891686.00 ( -18.14%)
pgscan_kswapd_normal                 0.00 (   0.00%)         0.00 (   0.00%)         0.00 (   0.00%)         0.00 (   0.00%)
pgscan_direct_dma                   71.00 (   0.00%)       134.00 (  47.01%)       243.00 (  70.78%)       352.00 (  79.83%)
pgscan_direct_dma32             305820.00 (   0.00%)    280204.00 (  -9.14%)    600518.00 (  49.07%)    957485.00 (  68.06%)
pgscan_direct_normal                 0.00 (   0.00%)         0.00 (   0.00%)         0.00 (   0.00%)         0.00 (   0.00%)
pageoutrun                       16296.00 (   0.00%)     21254.00 (  23.33%)     18447.00 (  11.66%)     20067.00 (  18.79%)
allocstall                         443.00 (   0.00%)       273.00 ( -62.27%)       513.00 (  13.65%)      1568.00 (  71.75%)

These are based on the raw figures taken from /proc/vmstat.  It's a rough
measure of reclaim activity.  Note that allocstall counts are higher
because we are entering direct reclaim more often as a result of not
sleeping in congestion.  In itself, it's not necessarily a bad thing.
It's easier to get a view of what happened from the vmscan tracepoint
report.

FTrace Reclaim Statistics: vmscan

                                traceonly-v2r2   lowlumpy-v2r3 waitcongest-v2r3 waitwriteback-v2r4
Direct reclaims                                443        273        513       1568
Direct reclaim pages scanned                305968     280402     600825     957933
Direct reclaim pages reclaimed               43503      19005      30327     117191
Direct reclaim write file async I/O              0          0          0          0
Direct reclaim write anon async I/O              0          3          4         12
Direct reclaim write file sync I/O               0          0          0          0
Direct reclaim write anon sync I/O               0          0          0          0
Wake kswapd requests                        187649     132338     191695     267701
Kswapd wakeups                                   3          1          4          1
Kswapd pages scanned                       4599269    4454162    4296815    3891906
Kswapd pages reclaimed                     2295947    2428434    2399818    2319706
Kswapd reclaim write file async I/O              1          0          1          1
Kswapd reclaim write anon async I/O             59        187         41        222
Kswapd reclaim write file sync I/O               0          0          0          0
Kswapd reclaim write anon sync I/O               0          0          0          0
Time stalled direct reclaim (seconds)         4.34       2.52       6.63       2.96
Time kswapd awake (seconds)                  11.15      10.25      11.01      10.19

Total pages scanned                        4905237   4734564   4897640   4849839
Total pages reclaimed                      2339450   2447439   2430145   2436897
%age total pages scanned/reclaimed          47.69%    51.69%    49.62%    50.25%
%age total pages scanned/written             0.00%     0.00%     0.00%     0.00%
%age  file pages scanned/written             0.00%     0.00%     0.00%     0.00%
Percentage Time Spent Direct Reclaim        29.23%    19.02%    38.48%    20.25%
Percentage Time kswapd Awake                78.58%    78.85%    76.83%    79.86%

What is interesting here for nocongest in particular is that while direct
reclaim scans more pages, the overall number of pages scanned remains the
same and the ratio of pages scanned to pages reclaimed is more or less the
same.  In other words, while we are sleeping less, reclaim is not doing
more work and as direct reclaim and kswapd is awake for less time, it
would appear to be doing less work.

FTrace Reclaim Statistics: congestion_wait
Direct number congest     waited                87        196         64          0
Direct time   congest     waited            4604ms     4732ms     5420ms        0ms
Direct full   congest     waited                72        145         53          0
Direct number conditional waited                 0          0        324       1315
Direct time   conditional waited               0ms        0ms        0ms        0ms
Direct full   conditional waited                 0          0          0          0
KSwapd number congest     waited                20         10         15          7
KSwapd time   congest     waited            1264ms      536ms      884ms      284ms
KSwapd full   congest     waited                10          4          6          2
KSwapd number conditional waited                 0          0          0          0
KSwapd time   conditional waited               0ms        0ms        0ms        0ms
KSwapd full   conditional waited                 0          0          0          0

The vanilla kernel spent 8 seconds asleep in direct reclaim and no time at
all asleep with the patches.

MMTests Statistics: duration
User/Sys Time Running Test (seconds)         10.51     10.73      10.6     11.66
Total Elapsed Time (seconds)                 14.19     13.00     14.33     12.76

Overall, the tests completed faster. It is interesting to note that backing off further
when a zone is congested and not just a BDI was more efficient overall.

PPC64 micro-mapped-file-stream
pgalloc_dma                    3024660.00 (   0.00%)   3027185.00 (   0.08%)   3025845.00 (   0.04%)   3026281.00 (   0.05%)
pgalloc_normal                       0.00 (   0.00%)         0.00 (   0.00%)         0.00 (   0.00%)         0.00 (   0.00%)
pgsteal_dma                    2508073.00 (   0.00%)   2565351.00 (   2.23%)   2463577.00 (  -1.81%)   2532263.00 (   0.96%)
pgsteal_normal                       0.00 (   0.00%)         0.00 (   0.00%)         0.00 (   0.00%)         0.00 (   0.00%)
pgscan_kswapd_dma              4601307.00 (   0.00%)   4128076.00 ( -11.46%)   3912317.00 ( -17.61%)   3377165.00 ( -36.25%)
pgscan_kswapd_normal                 0.00 (   0.00%)         0.00 (   0.00%)         0.00 (   0.00%)         0.00 (   0.00%)
pgscan_direct_dma               629825.00 (   0.00%)    971622.00 (  35.18%)   1063938.00 (  40.80%)   1711935.00 (  63.21%)
pgscan_direct_normal                 0.00 (   0.00%)         0.00 (   0.00%)         0.00 (   0.00%)         0.00 (   0.00%)
pageoutrun                       27776.00 (   0.00%)     20458.00 ( -35.77%)     18763.00 ( -48.04%)     18157.00 ( -52.98%)
allocstall                         977.00 (   0.00%)      2751.00 (  64.49%)      2098.00 (  53.43%)      5136.00 (  80.98%)

Similar trends to x86-64. allocstalls are up but it's not necessarily bad.

FTrace Reclaim Statistics: vmscan
Direct reclaims                                977       2709       2098       5136
Direct reclaim pages scanned                629825     963814    1063938    1711935
Direct reclaim pages reclaimed               75550     242538     150904     387647
Direct reclaim write file async I/O              0          0          0          2
Direct reclaim write anon async I/O              0         10          0          4
Direct reclaim write file sync I/O               0          0          0          0
Direct reclaim write anon sync I/O               0          0          0          0
Wake kswapd requests                        392119    1201712     571935     571921
Kswapd wakeups                                   3          2          3          3
Kswapd pages scanned                       4601307    4128076    3912317    3377165
Kswapd pages reclaimed                     2432523    2318797    2312673    2144616
Kswapd reclaim write file async I/O             20          1          1          1
Kswapd reclaim write anon async I/O             57        132         11        121
Kswapd reclaim write file sync I/O               0          0          0          0
Kswapd reclaim write anon sync I/O               0          0          0          0
Time stalled direct reclaim (seconds)         6.19       7.30      13.04      10.88
Time kswapd awake (seconds)                  21.73      26.51      25.55      23.90

Total pages scanned                        5231132   5091890   4976255   5089100
Total pages reclaimed                      2508073   2561335   2463577   2532263
%age total pages scanned/reclaimed          47.95%    50.30%    49.51%    49.76%
%age total pages scanned/written             0.00%     0.00%     0.00%     0.00%
%age  file pages scanned/written             0.00%     0.00%     0.00%     0.00%
Percentage Time Spent Direct Reclaim        18.89%    20.65%    32.65%    27.65%
Percentage Time kswapd Awake                72.39%    80.68%    78.21%    77.40%

Again, a similar trend that the congestion_wait changes mean that direct
reclaim scans more pages but the overall number of pages scanned while
slightly reduced, are very similar.  The ratio of scanning/reclaimed
remains roughly similar.  The downside is that kswapd and direct reclaim
was awake longer and for a larger percentage of the overall workload.
It's possible there were big differences in the amount of time spent
reclaiming slab pages between the different kernels which is plausible
considering that the micro tests runs after fsmark and sysbench.

Trace Reclaim Statistics: congestion_wait
Direct number congest     waited               845       1312        104          0
Direct time   congest     waited           19416ms    26560ms     7544ms        0ms
Direct full   congest     waited               745       1105         72          0
Direct number conditional waited                 0          0       1322       2935
Direct time   conditional waited               0ms        0ms       12ms      312ms
Direct full   conditional waited                 0          0          0          3
KSwapd number congest     waited                39        102         75         63
KSwapd time   congest     waited            2484ms     6760ms     5756ms     3716ms
KSwapd full   congest     waited                20         48         46         25
KSwapd number conditional waited                 0          0          0          0
KSwapd time   conditional waited               0ms        0ms        0ms        0ms
KSwapd full   conditional waited                 0          0          0          0

The vanilla kernel spent 20 seconds asleep in direct reclaim and only
312ms asleep with the patches.  The time kswapd spent congest waited was
also reduced by a large factor.

MMTests Statistics: duration
ser/Sys Time Running Test (seconds)         26.58     28.05      26.9     28.47
Total Elapsed Time (seconds)                 30.02     32.86     32.67     30.88

With all patches applies, the completion times are very similar.

X86-64 STRESS-HIGHALLOC
                traceonly-v2r2     lowlumpy-v2r3  waitcongest-v2r3waitwriteback-v2r4
Pass 1          82.00 ( 0.00%)    84.00 ( 2.00%)    85.00 ( 3.00%)    85.00 ( 3.00%)
Pass 2          90.00 ( 0.00%)    87.00 (-3.00%)    88.00 (-2.00%)    89.00 (-1.00%)
At Rest         92.00 ( 0.00%)    90.00 (-2.00%)    90.00 (-2.00%)    91.00 (-1.00%)

Success figures across the board are broadly similar.

                traceonly-v2r2     lowlumpy-v2r3  waitcongest-v2r3waitwriteback-v2r4
Direct reclaims                               1045        944        886        887
Direct reclaim pages scanned                135091     119604     109382     101019
Direct reclaim pages reclaimed               88599      47535      47863      46671
Direct reclaim write file async I/O            494        283        465        280
Direct reclaim write anon async I/O          29357      13710      16656      13462
Direct reclaim write file sync I/O             154          2          2          3
Direct reclaim write anon sync I/O           14594        571        509        561
Wake kswapd requests                          7491        933        872        892
Kswapd wakeups                                 814        778        731        780
Kswapd pages scanned                       7290822   15341158   11916436   13703442
Kswapd pages reclaimed                     3587336    3142496    3094392    3187151
Kswapd reclaim write file async I/O          91975      32317      28022      29628
Kswapd reclaim write anon async I/O        1992022     789307     829745     849769
Kswapd reclaim write file sync I/O               0          0          0          0
Kswapd reclaim write anon sync I/O               0          0          0          0
Time stalled direct reclaim (seconds)      4588.93    2467.16    2495.41    2547.07
Time kswapd awake (seconds)                2497.66    1020.16    1098.06    1176.82

Total pages scanned                        7425913  15460762  12025818  13804461
Total pages reclaimed                      3675935   3190031   3142255   3233822
%age total pages scanned/reclaimed          49.50%    20.63%    26.13%    23.43%
%age total pages scanned/written            28.66%     5.41%     7.28%     6.47%
%age  file pages scanned/written             1.25%     0.21%     0.24%     0.22%
Percentage Time Spent Direct Reclaim        57.33%    42.15%    42.41%    42.99%
Percentage Time kswapd Awake                43.56%    27.87%    29.76%    31.25%

Scanned/reclaimed ratios again look good with big improvements in
efficiency.  The Scanned/written ratios also look much improved.  With a
better scanned/written ration, there is an expectation that IO would be
more efficient and indeed, the time spent in direct reclaim is much
reduced by the full series and kswapd spends a little less time awake.

Overall, indications here are that allocations were happening much faster
and this can be seen with a graph of the latency figures as the
allocations were taking place
http://www.csn.ul.ie/~mel/postings/vmscanreduce-20101509/highalloc-interlatency-hydra-mean.ps

FTrace Reclaim Statistics: congestion_wait
Direct number congest     waited              1333        204        169          4
Direct time   congest     waited           78896ms     8288ms     7260ms      200ms
Direct full   congest     waited               756         92         69          2
Direct number conditional waited                 0          0         26        186
Direct time   conditional waited               0ms        0ms        0ms     2504ms
Direct full   conditional waited                 0          0          0         25
KSwapd number congest     waited                 4        395        227        282
KSwapd time   congest     waited             384ms    25136ms    10508ms    18380ms
KSwapd full   congest     waited                 3        232         98        176
KSwapd number conditional waited                 0          0          0          0
KSwapd time   conditional waited               0ms        0ms        0ms        0ms
KSwapd full   conditional waited                 0          0          0          0
KSwapd full   conditional waited               318          0        312          9

Overall, the time spent speeping is reduced.  kswapd is still hitting
congestion_wait() but that is because there are callers remaining where it
wasn't clear in advance if they should be changed to wait_iff_congested()
or not.  Overall the sleep imes are reduced though - from 79ish seconds to
about 19.

MMTests Statistics: duration
User/Sys Time Running Test (seconds)       3415.43   3386.65   3388.39    3377.5
Total Elapsed Time (seconds)               5733.48   3660.33   3689.41   3765.39

With the full series, the time to complete the tests are reduced by 30%

PPC64 STRESS-HIGHALLOC
                traceonly-v2r2     lowlumpy-v2r3  waitcongest-v2r3waitwriteback-v2r4
Pass 1          17.00 ( 0.00%)    34.00 (17.00%)    38.00 (21.00%)    43.00 (26.00%)
Pass 2          25.00 ( 0.00%)    37.00 (12.00%)    42.00 (17.00%)    46.00 (21.00%)
At Rest         49.00 ( 0.00%)    43.00 (-6.00%)    45.00 (-4.00%)    51.00 ( 2.00%)

Success rates there are *way* up particularly considering that the 16MB
huge pages on PPC64 mean that it's always much harder to allocate them.

FTrace Reclaim Statistics: vmscan
              stress-highalloc  stress-highalloc  stress-highalloc  stress-highalloc
                traceonly-v2r2     lowlumpy-v2r3  waitcongest-v2r3waitwriteback-v2r4
Direct reclaims                                499        505        564        509
Direct reclaim pages scanned                223478      41898      51818      45605
Direct reclaim pages reclaimed              137730      21148      27161      23455
Direct reclaim write file async I/O            399        136        162        136
Direct reclaim write anon async I/O          46977       2865       4686       3998
Direct reclaim write file sync I/O              29          0          1          3
Direct reclaim write anon sync I/O           31023        159        237        239
Wake kswapd requests                           420        351        360        326
Kswapd wakeups                                 185        294        249        277
Kswapd pages scanned                      15703488   16392500   17821724   17598737
Kswapd pages reclaimed                     5808466    2908858    3139386    3145435
Kswapd reclaim write file async I/O         159938      18400      18717      13473
Kswapd reclaim write anon async I/O        3467554     228957     322799     234278
Kswapd reclaim write file sync I/O               0          0          0          0
Kswapd reclaim write anon sync I/O               0          0          0          0
Time stalled direct reclaim (seconds)      9665.35    1707.81    2374.32    1871.23
Time kswapd awake (seconds)                9401.21    1367.86    1951.75    1328.88

Total pages scanned                       15926966  16434398  17873542  17644342
Total pages reclaimed                      5946196   2930006   3166547   3168890
%age total pages scanned/reclaimed          37.33%    17.83%    17.72%    17.96%
%age total pages scanned/written            23.27%     1.52%     1.94%     1.43%
%age  file pages scanned/written             1.01%     0.11%     0.11%     0.08%
Percentage Time Spent Direct Reclaim        44.55%    35.10%    41.42%    36.91%
Percentage Time kswapd Awake                86.71%    43.58%    52.67%    41.14%

While the scanning rates are slightly up, the scanned/reclaimed and
scanned/written figures are much improved.  The time spent in direct
reclaim and with kswapd are massively reduced, mostly by the lowlumpy
patches.

FTrace Reclaim Statistics: congestion_wait
Direct number congest     waited               725        303        126          3
Direct time   congest     waited           45524ms     9180ms     5936ms      300ms
Direct full   congest     waited               487        190         52          3
Direct number conditional waited                 0          0        200        301
Direct time   conditional waited               0ms        0ms        0ms     1904ms
Direct full   conditional waited                 0          0          0         19
KSwapd number congest     waited                 0          2         23          4
KSwapd time   congest     waited               0ms      200ms      420ms      404ms
KSwapd full   congest     waited                 0          2          2          4
KSwapd number conditional waited                 0          0          0          0
KSwapd time   conditional waited               0ms        0ms        0ms        0ms
KSwapd full   conditional waited                 0          0          0          0

Not as dramatic a story here but the time spent asleep is reduced and we
can still see what wait_iff_congested is going to sleep when necessary.

MMTests Statistics: duration
User/Sys Time Running Test (seconds)      12028.09   3157.17   3357.79   3199.16
Total Elapsed Time (seconds)              10842.07   3138.72   3705.54   3229.85

The time to complete this test goes way down.  With the full series, we
are allocating over twice the number of huge pages in 30% of the time and
there is a corresponding impact on the allocation latency graph available
at.

http://www.csn.ul.ie/~mel/postings/vmscanreduce-20101509/highalloc-interlatency-powyah-mean.ps

This patch:

Add a trace event for shrink_inactive_list() and updates the sample
postprocessing script appropriately.  It can be used to determine how many
pages were reclaimed and for non-lumpy reclaim where exactly the pages
were reclaimed from.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-26 16:52:07 -07:00
Wu Fengguang 1b430beee5 writeback: remove nonblocking/encountered_congestion references
This removes more dead code that was somehow missed by commit 0d99519efe
(writeback: remove unused nonblocking and congestion checks).  There are
no behavior change except for the removal of two entries from one of the
ext4 tracing interface.

The nonblocking checks in ->writepages are no longer used because the
flusher now prefer to block on get_request_wait() than to skip inodes on
IO congestion.  The latter will lead to more seeky IO.

The nonblocking checks in ->writepage are no longer used because it's
redundant with the WB_SYNC_NONE check.

We no long set ->nonblocking in VM page out and page migration, because
a) it's effectively redundant with WB_SYNC_NONE in current code
b) it's old semantic of "Don't get stuck on request queues" is mis-behavior:
   that would skip some dirty inodes on congestion and page out others, which
   is unfair in terms of LRU age.

Inspired by Christoph Hellwig. Thanks!

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: David Howells <dhowells@redhat.com>
Cc: Sage Weil <sage@newdream.net>
Cc: Steve French <sfrench@samba.org>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-26 16:52:05 -07:00
Ingo Molnar b8ecad8b2f Merge branch 'perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux-2.6 into perf/urgent 2010-10-23 20:05:43 +02:00
Linus Torvalds 91b745016c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: remove in_workqueue_context()
  workqueue: Clarify that schedule_on_each_cpu is synchronous
  memory_hotplug: drop spurious calls to flush_scheduled_work()
  shpchp: update workqueue usage
  pciehp: update workqueue usage
  isdn/eicon: don't call flush_scheduled_work() from diva_os_remove_soft_isr()
  workqueue: add and use WQ_MEM_RECLAIM flag
  workqueue: fix HIGHPRI handling in keep_working()
  workqueue: add queue_work and activate_work trace points
  workqueue: prepare for more tracepoints
  workqueue: implement flush[_delayed]_work_sync()
  workqueue: factor out start_flush_work()
  workqueue: cleanup flush/cancel functions
  workqueue: implement alloc_ordered_workqueue()

Fix up trivial conflict in fs/gfs2/main.c as per Tejun
2010-10-22 17:13:10 -07:00
Linus Torvalds bc4016f481 Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (29 commits)
  sched: Export account_system_vtime()
  sched: Call tick_check_idle before __irq_enter
  sched: Remove irq time from available CPU power
  sched: Do not account irq time to current task
  x86: Add IRQ_TIME_ACCOUNTING
  sched: Add IRQ_TIME_ACCOUNTING, finer accounting of irq time
  sched: Add a PF flag for ksoftirqd identification
  sched: Consolidate account_system_vtime extern declaration
  sched: Fix softirq time accounting
  sched: Drop group_capacity to 1 only if local group has extra capacity
  sched: Force balancing on newidle balance if local group has capacity
  sched: Set group_imb only a task can be pulled from the busiest cpu
  sched: Do not consider SCHED_IDLE tasks to be cache hot
  sched: Drop all load weight manipulation for RT tasks
  sched: Create special class for stop/migrate work
  sched: Unindent labels
  sched: Comment updates: fix default latency and granularity numbers
  tracing/sched: Add sched_pi_setprio tracepoint
  sched: Give CPU bound RT tasks preference
  sched: Try not to migrate higher priority RT tasks
  ...
2010-10-21 12:55:43 -07:00
Thomas Gleixner f4bc6bb2d5 tracing: Cleanup the convoluted softirq tracepoints
With the addition of trace_softirq_raise() the softirq tracepoint got
even more convoluted. Why the tracepoints take two pointers to assign
an integer is beyond my comprehension.

But adding an extra case which treats the first pointer as an unsigned
long when the second pointer is NULL including the back and forth
type casting is just horrible.

Convert the softirq tracepoints to take a single unsigned int argument
for the softirq vector number and fix the call sites.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <alpine.LFD.2.00.1010191428560.6815@localhost6.localdomain6>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: mathieu.desnoyers@efficios.com
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
2010-10-21 16:50:29 +02:00
Tejun Heo cdadf0097c workqueue: add queue_work and activate_work trace points
These two tracepoints allow tracking when and how a work is queued and
activated.  This patch is based on Frederic's patch to add queue_work
trace point.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
2010-10-05 10:49:55 +02:00
Tejun Heo 97bd234701 workqueue: prepare for more tracepoints
Define workqueue_work event class and use it for workqueue_execute_end
trace point.  Also, move trace/events/workqueue.h include downwards
such that all struct definitions are visible to it.  This is to
prepare for more tracepoints and doesn't cause any functional change.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
2010-10-05 10:41:14 +02:00
Steven Rostedt a8027073eb tracing/sched: Add sched_pi_setprio tracepoint
Add a tracepoint that shows the priority of a task being boosted
via priority inheritance.

Cc: Gregory Haskins <ghaskins@novell.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-09-21 10:56:41 -04:00
Jean Pihet 74704ac6ea tracing, perf: Add more power related events
This patch adds new generic events for dynamic power management
tracing:

 - clock events class: used for clock enable/disable and for
   clock rate change,
 - power_domain events class: used for power domains transitions.

The OMAP architecture will be using the new events for PM debugging,
however the new events are made generic enough to be used by all
platforms.

Signed-off-by: Jean Pihet <j-pihet@ti.com>
Acked-by: Thomas Renninger <trenn@suse.de>
Cc: discuss@lesswatts.org
Cc: linux-pm@lists.linux-foundation.org
Cc: Thomas Renninger <trenn@suse.de>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Kevin Hilman <khilman@deeprootsystems.com>
LKML-Reference: <AANLkTinUmbSUUuxUzc8++pcb9gd1CZFdyTQFrveTBXyV@mail.gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-17 09:10:43 +02:00
Koki Sanagi 07dc22e729 skb: Add tracepoints to freeing skb
This patch adds tracepoint to consume_skb and add trace_kfree_skb
before __kfree_skb in skb_free_datagram_locked and net_tx_action.
Combinating with tracepoint on dev_hard_start_xmit, we can check
how long it takes to free transmitted packets. And using it, we can
calculate how many packets driver had at that time. It is useful when
a drop of transmitted packet is a problem.

            sshd-6828  [000] 112689.258154: consume_skb: skbaddr=f2d99bb8

Signed-off-by: Koki Sanagi <sanagi.koki@jp.fujitsu.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Kaneshige Kenji <kaneshige.kenji@jp.fujitsu.com>
Cc: Izumo Taku <izumi.taku@jp.fujitsu.com>
Cc: Kosaki Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Scott Mcmillan <scott.a.mcmillan@intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
LKML-Reference: <4C724364.50903@jp.fujitsu.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-09-07 17:51:53 +02:00
Koki Sanagi cf66ba58b5 netdev: Add tracepoints to netdev layer
This patch adds tracepoint to dev_queue_xmit, dev_hard_start_xmit,
netif_rx and netif_receive_skb. These tracepoints help you to monitor
network driver's input/output.

          <idle>-0     [001] 112447.902030: netif_rx: dev=eth1 skbaddr=f3ef0900 len=84
          <idle>-0     [001] 112447.902039: netif_receive_skb: dev=eth1 skbaddr=f3ef0900 len=84
            sshd-6828  [000] 112447.903257: net_dev_queue: dev=eth4 skbaddr=f3fca538 len=226
            sshd-6828  [000] 112447.903260: net_dev_xmit: dev=eth4 skbaddr=f3fca538 len=226 rc=0

Signed-off-by: Koki Sanagi <sanagi.koki@jp.fujitsu.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Kaneshige Kenji <kaneshige.kenji@jp.fujitsu.com>
Cc: Izumo Taku <izumi.taku@jp.fujitsu.com>
Cc: Kosaki Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Scott Mcmillan <scott.a.mcmillan@intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
LKML-Reference: <4C72431E.3000901@jp.fujitsu.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-09-07 17:51:33 +02:00
Neil Horman 3e4b10d7a4 napi: Convert trace_napi_poll to TRACE_EVENT
This patch converts trace_napi_poll from DECLARE_EVENT to TRACE_EVENT
to improve the usability of napi_poll tracepoint.

          <idle>-0     [001] 241302.750777: napi_poll: napi poll on napi struct f6acc480 for device eth3
          <idle>-0     [000] 241302.852389: napi_poll: napi poll on napi struct f5d0d70c for device eth1

The original patch is below:
http://marc.info/?l=linux-kernel&m=126021713809450&w=2

[ sanagi.koki@jp.fujitsu.com: And add a fix by Steven Rostedt:
http://marc.info/?l=linux-kernel&m=126150506519173&w=2 ]

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Kaneshige Kenji <kaneshige.kenji@jp.fujitsu.com>
Cc: Izumo Taku <izumi.taku@jp.fujitsu.com>
Cc: Kosaki Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Scott Mcmillan <scott.a.mcmillan@intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
LKML-Reference: <4C7242D7.4050009@jp.fujitsu.com>
Signed-off-by: Koki Sanagi <sanagi.koki@jp.fujitsu.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-09-07 17:51:01 +02:00
Lai Jiangshan 2bf2160d88 irq: Add tracepoint to softirq_raise
Add a tracepoint for tracing when softirq action is raised.

This and the existing tracepoints complete softirq's tracepoints:
softirq_raise, softirq_entry and softirq_exit.

And when this tracepoint is used in combination with
the softirq_entry tracepoint we can determine
the softirq raise latency.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Cc: David Miller <davem@davemloft.net>
Cc: Kaneshige Kenji <kaneshige.kenji@jp.fujitsu.com>
Cc: Izumo Taku <izumi.taku@jp.fujitsu.com>
Cc: Kosaki Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Scott Mcmillan <scott.a.mcmillan@intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
LKML-Reference: <4C724298.4050509@jp.fujitsu.com>
[ factorize softirq events with DECLARE_EVENT_CLASS ]
Signed-off-by: Koki Sanagi <sanagi.koki@jp.fujitsu.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-09-07 17:49:34 +02:00
Linus Torvalds 502adf5778 Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  watchdog: Don't throttle the watchdog
  tracing: Fix timer tracing
2010-08-24 12:21:49 -07:00
Arjan van de Ven e36c886a0f workqueue: Add basic tracepoints to track workqueue execution
With the introduction of the new unified work queue thread pools,
we lost one feature: It's no longer possible to know which worker
is causing the CPU to wake out of idle. The result is that PowerTOP
now reports a lot of "kworker/a:b" instead of more readable results.

This patch adds a pair of tracepoints to the new workqueue code,
similar in style to the timer/hrtimer tracepoints.

With this pair of tracepoints, the next PowerTOP can correctly
report which work item caused the wakeup (and how long it took):

Interrupt (43)            i915      time   3.51ms    wakeups 141
Work      ieee80211_iface_work      time   0.81ms    wakeups  29
Work              do_dbs_timer      time   0.55ms    wakeups  24
Process                   Xorg      time  21.36ms    wakeups   4
Timer    sched_rt_period_timer      time   0.01ms    wakeups   1

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-21 13:19:37 -07:00
Arjan van de Ven ede1b42907 tracing: Fix timer tracing
PowerTOP would like to be able to trace timers.

Unfortunately, the current timer tracing is not very useful: the
actual timer function is not recorded in the trace at the start
of timer execution.

Although this is recorded for timer "start" time (when it gets
armed), this is not useful; most timers get started early, and a
tracer like PowerTOP will never see this event, but will only
see the actual running of the  timer.

This patch just adds the function to the timer tracing; I've
verified with PowerTOP that now it can get useful information
about timers.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: xiaoguangrong@cn.fujitsu.com
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: <stable@kernel.org> # .35.x, .34.x, .33.x
LKML-Reference: <4C6C5FA9.3000405@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-08-19 13:00:41 +02:00
Linus Torvalds 2f9e825d3e Merge branch 'for-2.6.36' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.36' of git://git.kernel.dk/linux-2.6-block: (149 commits)
  block: make sure that REQ_* types are seen even with CONFIG_BLOCK=n
  xen-blkfront: fix missing out label
  blkdev: fix blkdev_issue_zeroout return value
  block: update request stacking methods to support discards
  block: fix missing export of blk_types.h
  writeback: fix bad _bh spinlock nesting
  drbd: revert "delay probes", feature is being re-implemented differently
  drbd: Initialize all members of sync_conf to their defaults [Bugz 315]
  drbd: Disable delay probes for the upcomming release
  writeback: cleanup bdi_register
  writeback: add new tracepoints
  writeback: remove unnecessary init_timer call
  writeback: optimize periodic bdi thread wakeups
  writeback: prevent unnecessary bdi threads wakeups
  writeback: move bdi threads exiting logic to the forker thread
  writeback: restructure bdi forker loop a little
  writeback: move last_active to bdi
  writeback: do not remove bdi from bdi_list
  writeback: simplify bdi code a little
  writeback: do not lose wake-ups in bdi threads
  ...

Fixed up pretty trivial conflicts in drivers/block/virtio_blk.c and
drivers/scsi/scsi_error.c as per Jens.
2010-08-10 15:22:42 -07:00
KOSAKI Motohiro cc8e970c3c memcg: add mm_vmscan_memcg_isolate tracepoint
Memcg also need to trace page isolation information as global reclaim.
This patch does it.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-09 20:45:03 -07:00
KOSAKI Motohiro e17613c39b vmscan: convert mm_vmscan_lru_isolate to DEFINE_EVENT
Mel Gorman recently added some vmscan tracepoints.  Unfortunately they are
covered only global reclaim.  But we want to trace memcg reclaim too.

Thus, this patch convert them to DEFINE_TRACE macro.  it help to reuse
tracepoint definition for other similar usage (i.e.  memcg).  This patch
have no functionally change.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-09 20:45:03 -07:00
KOSAKI Motohiro bdce6d9ebf memcg, vmscan: add memcg reclaim tracepoint
Memcg also need to trace reclaim progress as direct reclaim.  This patch
add it.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-09 20:45:03 -07:00
KOSAKI Motohiro cf4dcc3e9b vmscan: convert direct reclaim tracepoint to DEFINE_TRACE
Mel Gorman recently added some vmscan tracepoints.  Unfortunately they are
covered only global reclaim.  But we want to trace memcg reclaim too.

Thus, this patch convert them to DEFINE_TRACE macro.  it help to reuse
tracepoint definition for other similar usage (i.e.  memcg).  This patch
have no functionally change.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-09 20:45:03 -07:00
Mel Gorman 755f0225e8 vmscan: tracing: add trace event when a page is written
Add a trace event for when page reclaim queues a page for IO and records
whether it is synchronous or asynchronous.  Excessive synchronous IO for a
process can result in noticeable stalls during direct reclaim.  Excessive
IO from page reclaim may indicate that the system is seriously under
provisioned for the amount of dirty pages that exist.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Larry Woodman <lwoodman@redhat.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Michael Rubin <mrubin@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-09 20:45:00 -07:00
Mel Gorman a8a94d1515 vmscan: tracing: add trace events for LRU page isolation
Add an event for when pages are isolated en-masse from the LRU lists.
This event augments the information available on LRU traffic and can be
used to evaluate lumpy reclaim.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Larry Woodman <lwoodman@redhat.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Michael Rubin <mrubin@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-09 20:44:59 -07:00
Mel Gorman 33906bc5c8 vmscan: tracing: add trace events for kswapd wakeup, sleeping and direct reclaim
Add two trace events for kswapd waking up and going asleep for the
purposes of tracking kswapd activity and two trace events for direct
reclaim beginning and ending.  The information can be used to work out how
much time a process or the system is spending on the reclamation of pages
and in the case of direct reclaim, how many pages were reclaimed for that
process.  High frequency triggering of these events could point to memory
pressure problems.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Larry Woodman <lwoodman@redhat.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Michael Rubin <mrubin@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-09 20:44:59 -07:00
Linus Torvalds 09dc942c2a Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (40 commits)
  ext4: Adding error check after calling ext4_mb_regular_allocator()
  ext4: Fix dirtying of journalled buffers in data=journal mode
  ext4: re-inline ext4_rec_len_(to|from)_disk functions
  jbd2: Remove t_handle_lock from start_this_handle()
  jbd2: Change j_state_lock to be a rwlock_t
  jbd2: Use atomic variables to avoid taking t_handle_lock in jbd2_journal_stop
  ext4: Add mount options in superblock
  ext4: force block allocation on quota_off
  ext4: fix freeze deadlock under IO
  ext4: drop inode from orphan list if ext4_delete_inode() fails
  ext4: check to make make sure bd_dev is set before dereferencing it
  jbd2: Make barrier messages less scary
  ext4: don't print scary messages for allocation failures post-abort
  ext4: fix EFBIG edge case when writing to large non-extent file
  ext4: fix ext4_get_blocks references
  ext4: Always journal quota file modifications
  ext4: Fix potential memory leak in ext4_fill_super
  ext4: Don't error out the fs if the user tries to make a file too big
  ext4: allocate stripe-multiple IOs on stripe boundaries
  ext4: move aio completion after unwritten extent conversion
  ...

Fix up conflicts in fs/ext4/inode.c as per Ted.

Fix up xfs conflicts as per earlier xfs merge.
2010-08-07 13:03:53 -07:00
Linus Torvalds 3b7433b8a8 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (55 commits)
  workqueue: mark init_workqueues() as early_initcall()
  workqueue: explain for_each_*cwq_cpu() iterators
  fscache: fix build on !CONFIG_SYSCTL
  slow-work: kill it
  gfs2: use workqueue instead of slow-work
  drm: use workqueue instead of slow-work
  cifs: use workqueue instead of slow-work
  fscache: drop references to slow-work
  fscache: convert operation to use workqueue instead of slow-work
  fscache: convert object to use workqueue instead of slow-work
  workqueue: fix how cpu number is stored in work->data
  workqueue: fix mayday_mask handling on UP
  workqueue: fix build problem on !CONFIG_SMP
  workqueue: fix locking in retry path of maybe_create_worker()
  async: use workqueue for worker pool
  workqueue: remove WQ_SINGLE_CPU and use WQ_UNBOUND instead
  workqueue: implement unbound workqueue
  workqueue: prepare for WQ_UNBOUND implementation
  libata: take advantage of cmwq and remove concurrency limitations
  workqueue: fix worker management invocation without pending works
  ...

Fixed up conflicts in fs/cifs/* as per Tejun. Other trivial conflicts in
include/linux/workqueue.h, kernel/trace/Kconfig and kernel/workqueue.c
2010-08-07 12:42:58 -07:00
Artem Bityutskiy 603320239f writeback: add new tracepoints
Add 2 new trace points to the periodic write-back wake up case, just like we do
in the 'bdi_queue_work()' function. Namely, introduce:

1. trace_writeback_wake_thread(bdi)
2. trace_writeback_wake_forker_thread(bdi)

The first event is triggered every time we wake up a bdi thread to start
periodic background write-out. The second event is triggered only when the bdi
thread does not exist and should be created by the forker thread.

This patch was suggested by Dave Chinner and Christoph Hellwig.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:53:56 +02:00
Randy Dunlap 96dccab1d6 writeback.h: needs linux/device.h
include/trace/events/writeback.h uses dev_name(), so it needs to
include linux/device.h.

include/trace/events/writeback.h:12: error: implicit declaration of function 'dev_name'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:26:35 +02:00
Dave Chinner 9e094383b6 writeback: Add tracing to write_cache_pages
Add a trace event to the ->writepage loop in write_cache_pages to give
visibility into how the ->writepage call is changing variables within the
writeback control structure. Of most interest is how wbc->nr_to_write changes
from call to call, especially with filesystems that write multiple pages
in ->writepage.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:24:26 +02:00
Dave Chinner 028c2dd184 writeback: Add tracing to balance_dirty_pages
Tracing high level background writeback events is good, but it doesn't
give the entire picture. Add visibility into write throttling to catch IO
dispatched by foreground throttling of processing dirtying lots of pages.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:24:25 +02:00
Dave Chinner 455b286468 writeback: Initial tracing support
Trace queue/sched/exec parts of the writeback loop. This provides
insight into when and why flusher threads are scheduled to run. e.g
a sync invocation leaves traces like:

     sync-[...]: writeback_queue: bdi 8:0: sb_dev 8:1 nr_pages=7712 sync_mode=0 kupdate=0 range_cyclic=0 background=0
flush-8:0-[...]: writeback_exec: bdi 8:0: sb_dev 8:1 nr_pages=7712 sync_mode=0 kupdate=0 range_cyclic=0 background=0

This also lays the foundation for adding more writeback tracing to
provide deeper insight into the whole writeback path.

The original tracing code is from Jens Axboe, though this version is
a rewrite as a result of the code being traced changing
significantly.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:24:23 +02:00
Christoph Hellwig 33659ebbae block: remove wrappers for request type/flags
Remove all the trivial wrappers for the cmd_type and cmd_flags fields in
struct requests.  This allows much easier grepping for different request
types instead of unwinding through macros.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:17:56 +02:00
Frederic Weisbecker 819ce45afe tracing: Drop cpparg() macro
Drop the cpparg() macro that wraps CPP parameters. We already have
the PARAM() macro for that, no need to have several versions.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
2010-08-02 01:31:28 +02:00
Theodore Ts'o e5880d76ae ext4: fix potential NULL dereference while tracing
The allocation_context pointer can be NULL.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-07-27 11:56:04 -04:00
Ingo Molnar 3a01736e70 Merge branch 'tip/perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into perf/core 2010-07-23 09:10:29 +02:00
Thomas Renninger 4c21adf26f x86 cpufreq, perf: Make trace_power_frequency cpufreq driver independent
and fix the broken case if a core's frequency depends on others.

trace_power_frequency was only implemented in a rather ungeneric
way in acpi-cpufreq driver's target() function only.

-> Move the call to trace_power_frequency to
   cpufreq.c:cpufreq_notify_transition() where CPUFREQ_POSTCHANGE
   notifier is triggered.
   This will support power frequency tracing by all cpufreq
   drivers.

trace_power_frequency did not trace frequency changes correctly
when the userspace governor was used or when CPU cores'
frequency depend on each other.

-> Moving this into the CPUFREQ_POSTCHANGE notifier and pass the cpu
   which gets switched automatically fixes this.

Robert Schoene provided some important fixes on top of my
initial quick shot version which are integrated in this patch:
- Forgot some changes in power_end trace (TP_printk/variable names)
- Variable dummy in power_end must now be cpu_id
- Use static 64 bit variable instead of unsigned int for cpu_id

[akpm@linux-foundation.org: build fix]
Signed-off-by: Thomas Renninger <trenn@suse.de>
Cc: davej@codemonkey.org.uk
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Dave Jones <davej@codemonkey.org.uk>
Acked-by: Arjan van de Ven <arjan@infradead.org>
Cc: Robert Schoene <robert.schoene@tu-dresden.de>
Tested-by: Robert Schoene <robert.schoene@tu-dresden.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2010-07-22 12:08:27 +02:00
Lai Jiangshan bc289ae98b tracing: Reduce latency and remove percpu trace_seq
__print_flags() and __print_symbolic() use percpu trace_seq:

1) Its memory is allocated at compile time, it wastes memory if we don't use tracing.
2) It is percpu data and it wastes more memory for multi-cpus system.
3) It disables preemption when it executes its core routine
   "trace_seq_printf(s, "%s: ", #call);" and introduces latency.

So we move this trace_seq to struct trace_iterator.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
LKML-Reference: <4C078350.7090106@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-07-20 22:05:34 -04:00
Tejun Heo 6416669975 workqueue: temporarily remove workqueue tracing
Strip tracing code from workqueue and remove workqueue tracing.  This
is temporary measure till concurrency managed workqueue is complete.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
2010-06-29 10:07:11 +02:00
Steven Rostedt a1d0ce8213 tracing: Use class->reg() for all registering of events
Because kprobes and syscalls need special processing to register
events, the class->reg() method was created to handle the differences.

But instead of creating a default ->reg for perf and ftrace events,
the code was scattered with:

	if (class->reg)
		class->reg();
	else
		default_reg();

This is messy and can also lead to bugs.

This patch cleans up this code and creates a default reg() entry for
the events allowing for the code to directly call the class->reg()
without the condition.

Reported-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-06-28 21:13:14 -04:00
Li Zefan 210f766915 tracing: Convert more sched events to DEFINE_EVENT
Convert sched_wait_task to DEFINE_EVENT, and save ~1K:

   text    data     bss     dec     hex filename
 104595    9424    4992  119011   1d0e3 kernel/sched.o.orig
 103619    9344    4992  117955   1ccc3 kernel/sched.o

No change in functionality.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4BFA3787.2040800@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-06-28 17:12:50 -04:00
Li Zefan 363d0f6490 tracing: Convert some timer events to DEFINE_EVENT
Use DECLARE_EVENT_CLASS, and save ~2.3K:

   text    data     bss     dec     hex filename
7018823 2031888 7251132 16301843         f8bf13 vmlinux.o.orig
7016727 2031696 7251132 16299555         f8b623 vmlinux.o

5 events are converted:

  timer_class:   timer_init, timer_expire_exit, timer_cancel
  hrtimer_class: hrtimer_init, hrtimer_cancel

No change in functionality.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4BFA3773.3060200@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-06-28 17:12:48 -04:00
Li Zefan c9642c49aa tracing: Use a global field list for all syscall exit events
All syscall exit events have the same fields.

The kernel size drops 2.5K:

   text    data     bss     dec     hex filename
7018612 2034376 7251132 16304120         f8c7f8 vmlinux.o.orig
7018612 2031888 7251132 16301632         f8be40 vmlinux.o

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4BFA3746.8070100@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-06-28 17:12:44 -04:00
Ingo Molnar 646b1db495 Merge commit 'v2.6.35-rc3' into perf/core
Merge reason: Go from -rc1 base to -rc3 base, merge in fixes.
2010-06-18 10:53:19 +02:00
Linus Torvalds 85ca7886f5 Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  tracing: Fix null pointer deref with SEND_SIG_FORCED
  perf: Fix signed comparison in perf_adjust_period()
  powerpc/oprofile: fix potential buffer overrun in op_model_cell.c
  perf symbols: Set the DSO long name when using symbol_conf.vmlinux_name
2010-06-10 09:30:09 -07:00
Ingo Molnar c726b61c6a Merge branch 'perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into perf/core 2010-06-09 18:55:57 +02:00
Dave Chinner 0b5649278e writeback: pay attention to wbc->nr_to_write in write_cache_pages
If a filesystem writes more than one page in ->writepage, write_cache_pages
fails to notice this and continues to attempt writeback when wbc->nr_to_write
has gone negative - this trace was captured from XFS:

    wbc_writeback_start: towrt=1024
    wbc_writepage: towrt=1024
    wbc_writepage: towrt=0
    wbc_writepage: towrt=-1
    wbc_writepage: towrt=-5
    wbc_writepage: towrt=-21
    wbc_writepage: towrt=-85

This has adverse effects on filesystem writeback behaviour. write_cache_pages()
needs to terminate after a certain number of pages are written, not after a
certain number of calls to ->writepage are made.  This is a regression
introduced by 17bc6c30cf ("vfs: Add
no_nrwrite_index_update writeback control flag"), but cannot be reverted
directly due to subsequent bug fixes that have gone in on top of it.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-06-08 18:12:44 -07:00
Oleg Nesterov b9b76dfaac tracing: Fix null pointer deref with SEND_SIG_FORCED
BUG: unable to handle kernel NULL pointer dereference at
	0000000000000006
IP: [<ffffffff8107bd37>] ftrace_raw_event_signal_generate+0x87/0x140

TP_STORE_SIGINFO() forgets about SEND_SIG_FORCED, fix.

We should probably export is_si_special() and change TP_STORE_SIGINFO()
to use it in the longer term.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Cc: 2.6.33.x-2.6.34.x <stable@kernel.org>
LKML-Reference: <20100603213409.GA8307@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-06-08 23:51:32 +02:00
Américo Wang 30dbb20e68 tracing: Remove boot tracer
The boot tracer is useless. It simply logs the initcalls
but in fact these initcalls are also logged through printk
while using the initcall_debug kernel parameter.

Nobody seem to be using it so far. Then just remove it.

Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Chase Douglas <chase.douglas@canonical.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <20100526105753.GA5677@cr0.nay.redhat.com>
[ remove the hooks in main.c, and the headers ]
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-06-08 23:31:28 +02:00
Frederic Weisbecker b0f82b81fe perf: Drop the skip argument from perf_arch_fetch_regs_caller
Drop this argument now that we always want to rewind only to the
state of the first caller.
It means frame pointers are not necessary anymore to reliably get
the source of an event. But this also means we need this helper
to be a macro now, as an inline function is not an option since
we need to know when to provide a default implentation.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Cc: David Miller <davem@davemloft.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-06-08 23:31:27 +02:00
Linus Torvalds 39d112100e Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched, trace: Fix sched_switch() prev_state argument
  sched: Fix wake_affine() vs RT tasks
  sched: Make sure timers have migrated before killing the migration_thread
2010-06-03 15:47:51 -07:00
Peter Zijlstra 02f726949f sched, trace: Fix sched_switch() prev_state argument
For CONFIG_PREEMPT=y kernels the sched_switch(.prev_state) argument isn't
useful because we can get preempted with current->state != TASK_RUNNING
without actually getting removed from the runqueue.

Cure this by treating all preempted tasks as runnable from the tracer's
point of view.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cautiously-acked-by: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <1275322715.27810.23323.camel@twins>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-06-01 09:27:17 +02:00