Commit Graph

298461 Commits

Author SHA1 Message Date
Tejun Heo 726fa6945e blkcg: simplify blkg_conf_prep()
blkg_conf_prep() implements "MAJ:MIN VAL" parsing manually, which is
unnecessary.  Just use sscanf("%u:%u %llu").  This might not reject
some malformed input (extra input at the end) but we don't care.

Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
Tejun Heo 3a8b31d396 blkcg: restructure blkio_group configruation setting
As part of userland interface restructuring, this patch updates
per-blkio_group configuration setting.  Instead of funneling
everything through a master function which has hard-coded cases for
each config file it may handle, the common part is factored into
blkg_conf_prep() and blkg_conf_finish() and different configuration
setters are implemented using the helpers.

While this doesn't result in immediate LOC reduction, this enables
further cleanups and more modular implementation.

Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
Tejun Heo c4682aec9c blkcg: restructure configuration printing
Similarly to the previous stat restructuring, this patch restructures
conf printing code such that,

* Conf printing uses the same helpers as stat.

* Printing function doesn't require hardcoded switching on the config
  being printed.  Note that this isn't complete yet for throttle
  confs.  The next patch will convert setting for these confs and will
  complete the transition.

* Printing uses read_seq_string callback (other methods will be phased
  out).

Note that blkio_group_conf.iops[2] is changed to u64 so that they can
be manipulated with the same functions.  This is transitional and will
go away later.

After this patch, per-device configurations - weight, bps and iops -
use __blkg_prfill_u64() for printing which uses white space as
delimiter instead of tab.

Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
Tejun Heo 627f29f481 blkcg: drop blkiocg_file_write_u64()
blkiocg_file_write_u64() has single switch case.  Drop
blkiocg_file_write_u64(), rename blkio_weight_write() to
blkcg_set_weight() and use it directly for .write_u64 callback.

Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:43 -07:00
Tejun Heo d3d32e69fa blkcg: restructure statistics printing
blkcg stats handling is a mess.  None of the stats has much to do with
blkcg core but they are all implemented in blkcg core.  Code sharing
is achieved by mixing common code with hard-coded cases for each stat
counter.

This patch restructures statistics printing such that

* Common logic exists as helper functions and specific print functions
  use the helpers to implement specific cases.

* Printing functions serving multiple counters don't require hardcoded
  switching on specific counters.

* Printing uses read_seq_string callback (other methods will be phased
  out).

This change enables further cleanups and relocating stats code to the
policy implementation it belongs to.

Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:42 -07:00
Tejun Heo edcb0722c6 blkcg: introduce blkg_stat and blkg_rwstat
blkcg uses u64_stats_sync to avoid reading wrong u64 statistic values
on 32bit archs and some stat counters have subtypes to distinguish
read/writes and sync/async IOs.  The stat code paths are confusing and
involve a lot of going back and forth between blkcg core and specific
policy implementations, and synchronization and subtype handling are
open coded in blkcg core.

This patch introduces struct blkg_stat and blkg_rwstat which, with
accompanying operations, encapsulate stat updating and accessing with
proper synchronization.

blkg_stat is simple u64 counter with 64bit read-access protection.
blkg_rwstat is the one with rw and [a]sync subcounters and takes @rw
flags to distinguish IO subtypes (%REQ_WRITE and %REQ_SYNC) and
replaces stat_sub_type indexed arrays.

All counters in blkio_group_stats and blkio_group_stats_cpu are
replaced with either blkg_stat or blkg_rwstat along with all users.

This does add one u64_stats_sync per counter and increase stats_sync
operations but they're empty/noops on 64bit archs and blkcg doesn't
have too many counters, especially with DEBUG_BLK_CGROUP off.

While the currently resulting code isn't necessarily simpler at the
moment, this will enable further clean up of blkcg stats code.

- BLKIO_STAT_{READ|WRITE|SYNC|ASYNC|TOTAL} renamed to
  BLKG_RWSTAT_{READ|WRITE|SYNC|ASYNC|TOTAL}.

- blkg_stat_add() replaces blkio_add_stat() and
  blkio_check_and_dec_stat().  Note that BUG_ON() on underflow in the
  latter function no longer exists.  It's *way* better to have
  underflowed stat counters than oopsing.

- blkio_group_stats->dequeue is now a proper u64 stat counter instead
  of ulong.

- reset_stats() updated to clear each stat counters individually and
  BLKG_STATS_DEBUG_CLEAR_{START|SIZE} are removed.

- Some functions reconstruct rw flags from direction and sync
  booleans.  This will be removed by future patches.

Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:42 -07:00
Tejun Heo 2aa4a1523b blkcg: BLKIO_STAT_CPU_SECTORS doesn't have subcounters
BLKIO_STAT_CPU_SECTORS doesn't need read/write/sync/async subcounters
and is counted by blkio_group_stats_cpu->sectors; however, it still
holds a member in blkio_group_stats_cpu->stat_arr_cpu.

Rearrange stat_type_cpu and define BLKIO_STAT_CPU_ARR_NR and use it
for stat_arr_cpu[] size so that only SERVICE_BYTES and SERVICED have
subcounters.

Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:42 -07:00
Tejun Heo aaec55a002 blkcg: remove unused @pol and @plid parameters
@pol to blkg_to_pdata() and @plid to blkg_lookup_create() are no
longer necessary.  Drop them.

Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 14:38:42 -07:00
Tejun Heo 959d851caa Merge branch 'for-3.5' of ../cgroup into block/for-3.5/core-merged
cgroup/for-3.5 contains the following changes which blk-cgroup needs
to proceed with the on-going cleanup.

* Dynamic addition and removal of cftypes to make config/stat file
  handling modular for policies.

* cgroup removal update to not wait for css references to drain to fix
  blkcg removal hang caused by cfq caching cfqgs.

Pull in cgroup/for-3.5 into block/for-3.5/core.  This causes the
following conflicts in block/blk-cgroup.c.

* 761b3ef50e "cgroup: remove cgroup_subsys argument from callbacks"
  conflicts with blkiocg_pre_destroy() addition and blkiocg_attach()
  removal.  Resolved by removing @subsys from all subsys methods.

* 676f7c8f84 "cgroup: relocate cftype and cgroup_subsys definitions in
  controllers" conflicts with ->pre_destroy() and ->attach() updates
  and removal of modular config.  Resolved by dropping forward
  declarations of the methods and applying updates to the relocated
  blkio_subsys.

* 4baf6e3325 "cgroup: convert all non-memcg controllers to the new
  cftype interface" builds upon the previous item.  Resolved by adding
  ->base_cftypes to the relocated blkio_subsys.

Signed-off-by: Tejun Heo <tj@kernel.org>
2012-04-01 12:55:00 -07:00
Tejun Heo 48ddbe1946 cgroup: make css->refcnt clearing on cgroup removal optional
Currently, cgroup removal tries to drain all css references.  If there
are active css references, the removal logic waits and retries
->pre_detroy() until either all refs drop to zero or removal is
cancelled.

This semantics is unusual and adds non-trivial complexity to cgroup
core and IMHO is fundamentally misguided in that it couples internal
implementation details (references to internal data structure) with
externally visible operation (rmdir).  To userland, this is a behavior
peculiarity which is unnecessary and difficult to expect (css refs is
otherwise invisible from userland), and, to policy implementations,
this is an unnecessary restriction (e.g. blkcg wants to hold css refs
for caching purposes but can't as that becomes visible as rmdir hang).

Unfortunately, memcg currently depends on ->pre_destroy() retrials and
cgroup removal vetoing and can't be immmediately switched to the new
behavior.  This patch introduces the new behavior of not waiting for
css refs to drain and maintains the old behavior for subsystems which
have __DEPRECATED_clear_css_refs set.

Once, memcg is updated, we can drop the code paths for the old
behavior as proposed in the following patch.  Note that the following
patch is incorrect in that dput work item is in cgroup and may lose
some of dputs when multiples css's are released back-to-back, and
__css_put() triggers check_for_release() when refcnt reaches 0 instead
of 1; however, it shows what part can be removed.

  http://thread.gmane.org/gmane.linux.kernel.containers/22559/focus=75251

Note that, in not-too-distant future, cgroup core will start emitting
warning messages for subsys which require the old behavior, so please
get moving.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
2012-04-01 12:09:56 -07:00
Tejun Heo 28b4c27b8e cgroup: use negative bias on css->refcnt to block css_tryget()
When a cgroup is about to be removed, cgroup_clear_css_refs() is
called to check and ensure that there are no active css references.

This is currently achieved by dropping the refcnt to zero iff it has
only the base ref.  If all css refs could be dropped to zero, ref
clearing is successful and CSS_REMOVED is set on all css.  If not, the
base ref is restored.  While css ref is zero w/o CSS_REMOVED set, any
css_tryget() attempt on it busy loops so that they are atomic
w.r.t. the whole css ref clearing.

This does work but dropping and re-instating the base ref is somewhat
hairy and makes it difficult to add more logic to the put path as
there are two of them - the regular css_put() and the reversible base
ref clearing.

This patch updates css ref clearing such that blocking new
css_tryget() and putting the base ref are separate operations.
CSS_DEACT_BIAS, defined as INT_MIN, is added to css->refcnt and
css_tryget() busy loops while refcnt is negative.  After all css refs
are deactivated, if they were all one, ref clearing succeeded and
CSS_REMOVED is set and the base ref is put using the regular
css_put(); otherwise, CSS_DEACT_BIAS is subtracted from the refcnts
and the original postive values are restored.

css_refcnt() accessor which always returns the unbiased positive
reference counts is added and used to simplify refcnt usages.  While
at it, relocate and reformat comments in cgroup_has_css_refs().

This separates css->refcnt deactivation and putting the base ref,
which enables the next patch to make ref clearing optional.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
2012-04-01 12:09:56 -07:00
Tejun Heo 79578621b4 cgroup: implement cgroup_rm_cftypes()
Implement cgroup_rm_cftypes() which removes an array of cftypes from a
subsystem.  It can be called whether the target subsys is attached or
not.  cgroup core will remove the specified file from all existing
cgroups.

This will be used to improve sub-subsys modularity and will be helpful
for unified hierarchy.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
2012-04-01 12:09:56 -07:00
Tejun Heo 05ef1d7c4a cgroup: introduce struct cfent
This patch adds cfent (cgroup file entry) which is the association
between a cgroup and a file.  This is in-cgroup representation of
files under a cgroup directory.  This simplifies walking walking
cgroup files and thus cgroup_clear_directory(), which is now
implemented in two parts - cgroup_rm_file() and a loop around it.

cgroup_rm_file() will be used to implement cftype removal and cfent is
scheduled to serve cgroup specific per-file data (e.g. for sysfs-like
"sever" semantics).

v2: - cfe was freed from cgroup_rm_file() which led to use-after-free
      if the file had openers at the time of removal.  Moved to
      cgroup_diput().

    - cgroup_clear_directory() triggered WARN_ON_ONCE() if d_subdirs
      wasn't empty after removing all files.  This triggered
      spuriously if some files were open during directory clearing.
      Removed.

v3: - In cgroup_diput(), WARN_ONCE(!list_empty(&cfe->node)) could be
      spuriously triggered for root cgroups because they don't go
      through cgroup_clear_directory() on unmount.  Don't trigger WARN
      for root cgroups.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Glauber Costa <glommer@parallels.com>
2012-04-01 12:09:56 -07:00
Tejun Heo f6ea93723d cgroup: relocate __d_cgrp() and __d_cft()
Move the two macros upwards as they'll be used earlier in the file.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
2012-04-01 12:09:55 -07:00
Tejun Heo db0416b649 cgroup: remove cgroup_add_file[s]()
No controller is using cgroup_add_files[s]().  Unexport them, and
convert cgroup_add_files() to handle NULL entry terminated array
instead of taking count explicitly and continue creation on failure
for internal use.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
2012-04-01 12:09:55 -07:00
Tejun Heo 6bc103498f cgroup: convert memcg controller to the new cftype interface
Convert memcg to use the new cftype based interface.  kmem support
abuses ->populate() for mem_cgroup_sockets_init() so it can't be
removed at the moment.

tcp_memcontrol is updated so that tcp_files[] is registered via a
__initcall.  This change also allows removing the forward declaration
of tcp_files[].  Removed.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Glauber Costa <glommer@parallels.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Greg Thelen <gthelen@google.com>
2012-04-01 12:09:55 -07:00
Tejun Heo af36f906c0 memcg: always create memsw files if CONFIG_CGROUP_MEM_RES_CTLR_SWAP
Instead of conditioning creation of memsw files on do_swap_account,
always create the files if compiled-in and fail read/write attempts
with -EOPNOTSUPP if !do_swap_account.

This is suggested by KAMEZAWA to simplify memcg file creation so that
it can use cgroup->subsys_cftypes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
2012-04-01 12:09:55 -07:00
Tejun Heo 4baf6e3325 cgroup: convert all non-memcg controllers to the new cftype interface
Convert debug, freezer, cpuset, cpu_cgroup, cpuacct, net_prio, blkio,
net_cls and device controllers to use the new cftype based interface.
Termination entry is added to cftype arrays and populate callbacks are
replaced with cgroup_subsys->base_cftypes initializations.

This is functionally identical transformation.  There shouldn't be any
visible behavior change.

memcg is rather special and will be converted separately.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Paul Menage <paul@paulmenage.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Vivek Goyal <vgoyal@redhat.com>
2012-04-01 12:09:55 -07:00
Tejun Heo 676f7c8f84 cgroup: relocate cftype and cgroup_subsys definitions in controllers
blk-cgroup, netprio_cgroup, cls_cgroup and tcp_memcontrol
unnecessarily define cftype array and cgroup_subsys structures at the
top of the file, which is unconventional and necessiates forward
declaration of methods.

This patch relocates those below the definitions of the methods and
removes the forward declarations.  Note that forward declaration of
tcp_files[] is added in tcp_memcontrol.c for tcp_init_cgroup().  This
will be removed soon by another patch.

This patch doesn't introduce any functional change.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
2012-04-01 12:09:55 -07:00
Tejun Heo 6e6ff25bd5 cgroup: merge cft_release_agent cftype array into the base files array
Now that cftype can express whether a file should only be on root,
cft_release_agent can be merged into the base files cftypes array.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
2012-04-01 12:09:55 -07:00
Tejun Heo 8e3f6541d4 cgroup: implement cgroup_add_cftypes() and friends
Currently, cgroup directories are populated by subsys->populate()
callback explicitly creating files on each cgroup creation.  This
level of flexibility isn't needed or desirable.  It provides largely
unused flexibility which call for abuses while severely limiting what
the core layer can do through the lack of structure and conventions.

Per each cgroup file type, the only distinction that cgroup users is
making is whether a cgroup is root or not, which can easily be
expressed with flags.

This patch introduces cgroup_add_cftypes().  These deal with cftypes
instead of individual files - controllers indicate that certain types
of files exist for certain subsystem.  Newly added CFTYPE_*_ON_ROOT
flags indicate whether a cftype should be excluded or created only on
the root cgroup.

cgroup_add_cftypes() can be called any time whether the target
subsystem is currently attached or not.  cgroup core will create files
on the existing cgroups as necessary.

Also, cgroup_subsys->base_cftypes is added to ease registration of the
base files for the subsystem.  If non-NULL on subsys init, the cftypes
pointed to by ->base_cftypes are automatically registered on subsys
init / load.

Further patches will convert the existing users and remove the file
based interface.  Note that this interface allows dynamic addition of
files to an active controller.  This will be used for sub-controller
modularity and unified hierarchy in the longer term.

This patch implements the new mechanism but doesn't apply it to any
user.

v2: replaced DECLARE_CGROUP_CFTYPES[_COND]() with
    cgroup_subsys->base_cftypes, which works better for cgroup_subsys
    which is loaded as module.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
2012-04-01 12:09:55 -07:00
Tejun Heo b0ca5a84fc cgroup: build list of all cgroups under a given cgroupfs_root
Build a list of all cgroups anchored at cgroupfs_root->allcg_list and
going through cgroup->allcg_node.  The list is protected by
cgroup_mutex and will be used to improve cgroup file handling.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
2012-04-01 12:09:54 -07:00
Tejun Heo ff4c8d503e cgroup: move cgroup_clear_directory() call out of cgroup_populate_dir()
cgroup_populate_dir() currently clears all files and then repopulate
the directory; however, the clearing part is only useful when it's
called from cgroup_remount().  Relocate the invocation to
cgroup_remount().

This is to prepare for further cgroup file handling updates.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
2012-04-01 12:09:54 -07:00
Tejun Heo 8b5a5a9dbc cgroup: deprecate remount option changes
This patch marks the following features for deprecation.

* Rebinding subsys by remount: Never reached useful state - only works
  on empty hierarchies.

* release_agent update by remount: release_agent itself will be
  replaced with conventional fsnotify notification.

v2: Lennart pointed out that "name=" is necessary for mounts w/o any
    controller attached.  Drop "name=" deprecation.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Lennart Poettering <mzxreary@0pointer.de>
2012-04-01 12:09:54 -07:00
Linus Torvalds dd775ae254 Linux 3.4-rc1 2012-03-31 16:24:09 -07:00
Linus Torvalds b7ffff4bb3 Merge branch 's3-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/amit/virtio-console
Pull virtio S3 support patches from Amit Shah:
 "Turns out S3 is not different from S4 for virtio devices: the device
  is assumed to be reset, so the host and guest state are to be assumed
  to be out of sync upon resume.  We handle the S4 case with exactly the
  same scenario, so just point the suspend/resume routines to the
  freeze/restore ones.

  Once that is done, we also use the PM API's macro to initialise the
  sleep functions.

  A couple of cleanups are included: there's no need for special thaw
  processing in the balloon driver, so that's addressed in patches 1 and
  2.

  Testing: both S3 and S4 support have been tested using these patches
  using a similar method used earlier during S4 patch development: a
  guest is started with virtio-blk as the only disk, a virtio network
  card, a virtio-serial port and a virtio balloon device.  Ping from
  guest to host, dd /dev/zero to a file on the disk, and IO from the
  host on the virtio-serial port, all at once, while exercising S4 and
  S3 (separately) were tested.  They all continue to work fine after
  resume.  virtio balloon values too were tested by inflating and
  deflating the balloon."

Pulling from Amit, since Rusty is off getting married (and presumably
shaving people).

* 's3-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/amit/virtio-console:
  virtio-pci: switch to PM ops macro to initialise PM functions
  virtio-pci: S3 support
  virtio-pci: drop restore_common()
  virtio: drop thaw PM operation
  virtio: balloon: Allow stats update after restore from S4
2012-03-31 15:11:39 -07:00
Linus Torvalds 8bb1f22952 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull second try at vfs part d#2 from Al Viro:
 "Miklos' first series (with do_lookup() rewrite split into edible
  chunks) + assorted bits and pieces.

  The 'untangling of do_lookup()' series is is a splitup of what used to
  be a monolithic patch from Miklos, so this series is basically "how do
  I convince myself that his patch is correct (or find a hole in it)".
  No holes found and I like the resulting cleanup, so in it went..."

Changes from try 1: Fix a boot problem with selinux, and commit messages
prettied up a bit.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (24 commits)
  vfs: fix out-of-date dentry_unhash() comment
  vfs: split __lookup_hash
  untangling do_lookup() - take __lookup_hash()-calling case out of line.
  untangling do_lookup() - switch to calling __lookup_hash()
  untangling do_lookup() - merge d_alloc_and_lookup() callers
  untangling do_lookup() - merge failure exits in !dentry case
  untangling do_lookup() - massage !dentry case towards __lookup_hash()
  untangling do_lookup() - get rid of need_reval in !dentry case
  untangling do_lookup() - eliminate a loop.
  untangling do_lookup() - expand the area under ->i_mutex
  untangling do_lookup() - isolate !dentry stuff from the rest of it.
  vfs: move MAY_EXEC check from __lookup_hash()
  vfs: don't revalidate just looked up dentry
  vfs: fix d_need_lookup/d_revalidate order in do_lookup
  ext3: move headers to fs/ext3/
  migrate ext2_fs.h guts to fs/ext2/ext2.h
  new helper: ext2_image_size()
  get rid of pointless includes of ext2_fs.h
  ext2: No longer export ext2_fs.h to user space
  mtdchar: kill persistently held vfsmount
  ...
2012-03-31 13:42:57 -07:00
Linus Torvalds f22e08a79f Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar.

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Fix incorrect usage of for_each_cpu_mask() in select_fallback_rq()
  sched: Fix __schedule_bug() output when called from an interrupt
  sched/arch: Introduce the finish_arch_post_lock_switch() scheduler callback
2012-03-31 13:35:31 -07:00
Linus Torvalds f187e9fd68 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates and fixes from Ingo Molnar:
 "It's mostly fixes, but there's also two late items:

   - preliminary GTK GUI support for perf report
   - PMU raw event format descriptors in sysfs, to be parsed by tooling

  The raw event format in sysfs is a new ABI.  For example for the 'CPU'
  PMU we have:

    aldebaran:~> ll /sys/bus/event_source/devices/cpu/format/*
    -r--r--r--. 1 root root 4096 Mar 31 10:29 /sys/bus/event_source/devices/cpu/format/any
    -r--r--r--. 1 root root 4096 Mar 31 10:29 /sys/bus/event_source/devices/cpu/format/cmask
    -r--r--r--. 1 root root 4096 Mar 31 10:29 /sys/bus/event_source/devices/cpu/format/edge
    -r--r--r--. 1 root root 4096 Mar 31 10:29 /sys/bus/event_source/devices/cpu/format/event
    -r--r--r--. 1 root root 4096 Mar 31 10:29 /sys/bus/event_source/devices/cpu/format/inv
    -r--r--r--. 1 root root 4096 Mar 31 10:29 /sys/bus/event_source/devices/cpu/format/offcore_rsp
    -r--r--r--. 1 root root 4096 Mar 31 10:29 /sys/bus/event_source/devices/cpu/format/pc
    -r--r--r--. 1 root root 4096 Mar 31 10:29 /sys/bus/event_source/devices/cpu/format/umask

  those lists of fields contain a specific format:

    aldebaran:~> cat /sys/bus/event_source/devices/cpu/format/offcore_rsp
    config1:0-63

  So, those who wish to specify raw events can now use the following
  event format:

    -e cpu/cmask=1,event=2,umask=3

  Most people will not want to specify any events (let alone raw
  events), they'll just use whatever default event the tools use.

  But for more obscure PMU events that have no cross-architecture
  generic events the above syntax is more usable and a bit more
  structured than specifying hex numbers."

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (41 commits)
  perf tools: Remove auto-generated bison/flex files
  perf annotate: Fix off by one symbol hist size allocation and hit accounting
  perf tools: Add missing ref-cycles event back to event parser
  perf annotate: addr2line wants addresses in same format as objdump
  perf probe: Finder fails to resolve function name to address
  tracing: Fix ent_size in trace output
  perf symbols: Handle NULL dso in dso__name_len
  perf symbols: Do not include libgen.h
  perf tools: Fix bug in raw sample parsing
  perf tools: Fix display of first level of callchains
  perf tools: Switch module.h into export.h
  perf: Move mmap page data_head offset assertion out of header
  perf: Fix mmap_page capabilities and docs
  perf diff: Fix to work with new hists design
  perf tools: Fix modifier to be applied on correct events
  perf tools: Fix various casting issues for 32 bits
  perf tools: Simplify event_read_id exit path
  tracing: Fix ftrace stack trace entries
  tracing: Move the tracing_on/off() declarations into CONFIG_TRACING
  perf report: Add a simple GTK2-based 'perf report' browser
  ...
2012-03-31 13:34:04 -07:00
Linus Torvalds adb3b1f3fc PARISC misc on 20120331
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Merge tag 'parisc-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/parisc-2.6

Pull PARISC misc updates from James Bottomley:
 "This is a couple of minor updates (fixing lws futex locking and
  removing some obsolete cpu_*_map calls)."

* tag 'parisc-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/parisc-2.6:
  [PARISC] remove references to cpu_*_map.
  [PARISC] futex: Use same lock set as lws calls
2012-03-31 13:32:30 -07:00
Linus Torvalds a75ee6ecd4 SCSI updates on 20120331
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6

Pull SCSI updates from James Bottomley:
 "This is primarily another round of driver updates (lpfc, bfa, fcoe,
  ipr) plus a new ufshcd driver.  There shouldn't be anything
  controversial in here (The final deletion of scsi proc_ops which
  caused some build breakage has been held over until the next merge
  window to give us more time to stabilise it).

  I'm afraid, with me moving continents at exactly the wrong time,
  anything submitted after the merge window opened has been held over to
  the next merge window."

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (63 commits)
  [SCSI] ipr: Driver version 2.5.3
  [SCSI] ipr: Increase alignment boundary of command blocks
  [SCSI] ipr: Increase max concurrent oustanding commands
  [SCSI] ipr: Remove unnecessary memory barriers
  [SCSI] ipr: Remove unnecessary interrupt clearing on new adapters
  [SCSI] ipr: Fix target id allocation re-use problem
  [SCSI] atp870u, mpt2sas, qla4xxx use pci_dev->revision
  [SCSI] fcoe: Drop the rtnl_mutex before calling fcoe_ctlr_link_up
  [SCSI] bfa: Update the driver version to 3.0.23.0
  [SCSI] bfa: BSG and User interface fixes.
  [SCSI] bfa: Fix to avoid vport delete hang on request queue full scenario.
  [SCSI] bfa: Move service parameter programming logic into firmware.
  [SCSI] bfa: Revised Fabric Assigned Address(FAA) feature implementation.
  [SCSI] bfa: Flash controller IOC pll init fixes.
  [SCSI] bfa: Serialize the IOC hw semaphore unlock logic.
  [SCSI] bfa: Modify ISR to process pending completions
  [SCSI] bfa: Add fc host issue lip support
  [SCSI] mpt2sas: remove extraneous sas_log_info messages
  [SCSI] libfc: fcoe_transport_create fails in single-CPU environment
  [SCSI] fcoe: reduce contention for fcoe_rx_list lock [v2]
  ...
2012-03-31 13:31:23 -07:00
J. Bruce Fields c0d0259481 vfs: fix out-of-date dentry_unhash() comment
64252c75a2 "vfs: remove dget() from
dentry_unhash()" changed the implementation but not the comment.

Cc: Sage Weil <sage@newdream.net>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-31 16:03:17 -04:00
Miklos Szeredi bad6118978 vfs: split __lookup_hash
Split __lookup_hash into two component functions:

 lookup_dcache - tries cached lookup, returns whether real lookup is needed
 lookup_real - calls i_op->lookup

This eliminates code duplication between d_alloc_and_lookup() and
d_inode_lookup().

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-31 16:03:17 -04:00
Al Viro 81e6f52089 untangling do_lookup() - take __lookup_hash()-calling case out of line.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-31 16:03:17 -04:00
Al Viro a32555466c untangling do_lookup() - switch to calling __lookup_hash()
now we have __lookup_hash() open-coded if !dentry case;
just call the damn thing instead...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-31 16:03:16 -04:00
Al Viro a6ecdfcfba untangling do_lookup() - merge d_alloc_and_lookup() callers
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-31 16:03:16 -04:00
Al Viro ec335e91a4 untangling do_lookup() - merge failure exits in !dentry case
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-31 16:03:16 -04:00
Al Viro d774a058d9 untangling do_lookup() - massage !dentry case towards __lookup_hash()
Reorder if-else cases for starters...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-31 16:03:16 -04:00
Al Viro 08b0ab7c20 untangling do_lookup() - get rid of need_reval in !dentry case
Everything arriving into if (!dentry) will have need_reval = 1.
Indeed, the only way to get there with need_reval reset to 0 would
be via
	if (unlikely(d_need_lookup(dentry)))
		goto unlazy;
	if (unlikely(dentry->d_flags & DCACHE_OP_REVALIDATE)) {
		status = d_revalidate(dentry, nd);
	if (unlikely(status <= 0)) {
		if (status != -ECHILD)
			need_reval = 0;
		goto unlazy;
...
unlazy:
	/* no assignments to dentry */
	if (dentry && unlikely(d_need_lookup(dentry))) {
		dput(dentry);
		dentry = NULL;
	}
and if d_need_lookup() had already been false the first time around, it
will remain false on the second call as well.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-31 16:03:16 -04:00
Al Viro acc9cb3cd4 untangling do_lookup() - eliminate a loop.
d_lookup() *will* fail after successful d_invalidate(), if we are
holding i_mutex all along.  IOW, we don't need to jump back to
l: - we know what path will be taken there and can do that (i.e.
d_alloc_and_lookup()) directly.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-31 16:03:16 -04:00
Al Viro 37c17e1f37 untangling do_lookup() - expand the area under ->i_mutex
keep holding ->i_mutex over revalidation parts

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-31 16:03:16 -04:00
Al Viro 3f6c7c71a2 untangling do_lookup() - isolate !dentry stuff from the rest of it.
Duplicate the revalidation-related parts into if (!dentry) branch.
Next step will be to pull them under i_mutex.

This and the next 8 commits are more or less a splitup of patch
by Miklos; folks, when you are working with something that convoluted,
carve your patches up into easily reviewed steps, especially when
a lot of codepaths involved are rarely hit...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-31 16:03:16 -04:00
Miklos Szeredi cda309de25 vfs: move MAY_EXEC check from __lookup_hash()
The only caller of __lookup_hash() that needs the exec permission check on
parent is lookup_one_len().

All lookup_hash() callers already checked permission in LOOKUP_PARENT walk.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-31 16:03:16 -04:00
Miklos Szeredi 3637c05d88 vfs: don't revalidate just looked up dentry
__lookup_hash() calls ->lookup() if the dentry needs lookup and on success
revalidates the dentry (all under dir->i_mutex).

While this is harmless it doesn't make a lot of sense.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-31 16:03:16 -04:00
Miklos Szeredi fa4ee15951 vfs: fix d_need_lookup/d_revalidate order in do_lookup
Doing revalidate on a dentry which has not yet been looked up makes no sense.

Move the d_need_lookup() check before d_revalidate().

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-31 16:03:16 -04:00
Al Viro 4613ad180d ext3: move headers to fs/ext3/
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-31 16:03:16 -04:00
Al Viro f7699f2b01 migrate ext2_fs.h guts to fs/ext2/ext2.h
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-31 16:03:16 -04:00
Al Viro 39429c5e4a new helper: ext2_image_size()
... implemented that way since the next commit will leave it
almost alone in ext2_fs.h - most of the file (including
struct ext2_super_block) is going to move to fs/ext2/ext2.h.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-31 16:03:16 -04:00
Al Viro 2f99c36986 get rid of pointless includes of ext2_fs.h
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-31 16:03:15 -04:00
Thierry Reding 4a165d25f6 ext2: No longer export ext2_fs.h to user space
Since the on-disk format has been stable for quite some time, users
should either use the headers provided by libext2fs or keep a private
copy of this header. For the full discussion, see this thread:

	https://lkml.org/lkml/2012/3/21/516

While at it, this commit removes all __KERNEL__ guards, which are now
unnecessary.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Jan Kara <jack@suse.cz>
Cc: Ted Ts'o <tytso@mit.edu>
Cc: Artem Bityutskiy <dedekind1@gmail.com>
Cc: Andreas Dilger <aedilger@gmail.com>
Cc: linux-ext4@vger.kernel.org
2012-03-31 16:03:15 -04:00