Impact: clean up swiotlb printks
Remove duplicated swiotlb info printing, and make it more detailed.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: prepare the swiotlb code for HighMem struct pages
This requires us to treat DMA regions in terms of page+offset rather
than virtual addressing since a HighMem page may not have a mapping.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: generalize the sw-IOTLB range checks
Some architectures require special rules to determine whether a range
needs mapping or not. This adds a weak function for architectures to
override.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: generalize phys<->bus<->phys conversions in the swiotlb code
Architectures may need to override these conversions. Implement a
__weak hook point containing the default implementation.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: generalize swiotlb allocation code
Architectures may need to allocate memory specially for use with
the swiotlb. Create the weak function swiotlb_alloc_boot() and
swiotlb_alloc() defaulting to the current behaviour.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The last patch to lib/idr.c caused a bug if idr_get_new_above() was
called on an empty idr.
Usually, nodes stay on the same layer. New layers are added to the top
of the tree.
The exception is idr_get_new_above() on an empty tree: In this case, the
new root node is first added on layer 0, then moved upwards. p->layer
was not updated.
As usual: You shall never rely on the source code comments, they will
only mislead you.
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Revert
commit e8ced39d5e
Author: Mingming Cao <cmm@us.ibm.com>
Date: Fri Jul 11 19:27:31 2008 -0400
percpu_counter: new function percpu_counter_sum_and_set
As described in
revert "percpu counter: clean up percpu_counter_sum_and_set()"
the new percpu_counter_sum_and_set() is racy against updates to the
cpu-local accumulators on other CPUs. Revert that change.
This means that ext4 will be slow again. But correct.
Reported-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mingming Cao <cmm@us.ibm.com>
Cc: <linux-ext4@vger.kernel.org>
Cc: <stable@kernel.org> [2.6.27.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Revert
commit 1f7c14c62c
Author: Mingming Cao <cmm@us.ibm.com>
Date: Thu Oct 9 12:50:59 2008 -0400
percpu counter: clean up percpu_counter_sum_and_set()
Before this patch we had the following:
percpu_counter_sum(): return the percpu_counter's value
percpu_counter_sum_and_set(): return the percpu_counter's value, copying
that value into the central value and zeroing the per-cpu counters before
returning.
After this patch, percpu_counter_sum_and_set() has gone, and
percpu_counter_sum() gets the old percpu_counter_sum_and_set()
functionality.
Problem is, as Eric points out, the old percpu_counter_sum_and_set()
functionality was racy and wrong. It zeroes out counters on "other" cpus,
without holding any locks which will prevent races agaist updates from
those other CPUS.
This patch reverts 1f7c14c62c. This means
that percpu_counter_sum_and_set() still has the race, but
percpu_counter_sum() does not.
Note that this is not a simple revert - ext4 has since started using
percpu_counter_sum() for its dirty_blocks counter as well.
Note that this revert patch changes percpu_counter_sum() semantics.
Before the patch, a call to percpu_counter_sum() will bring the counter's
central counter mostly up-to-date, so a following percpu_counter_read()
will return a close value.
After this patch, a call to percpu_counter_sum() will leave the counter's
central accumulator unaltered, so a subsequent call to
percpu_counter_read() can now return a significantly inaccurate result.
If there is any code in the tree which was introduced after
e8ced39d5e was merged, and which depends
upon the new percpu_counter_sum() semantics, that code will break.
Reported-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mingming Cao <cmm@us.ibm.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We should first delete the counter from percpu_counters list
before freeing memory, or a percpu_counter_hotcpu_callback()
could dereference a NULL pointer.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2nd part of the fixes needed for
http://bugzilla.kernel.org/show_bug.cgi?id=11796.
When the idr tree is either grown or shrunk, then the update to the number
of layers and the top pointer were not atomic. This race caused crashes.
The attached patch fixes that by replicating the layers counter in each
layer, thus idr_find doesn't need idp->layers anymore.
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Clement Calmels <cboulte@gmail.com>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Pierre Peiffer <peifferp@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kunmap() takes as argument the struct page that orginally got kmap()'d,
however the sg_miter_stop() function passed it the kernel virtual address
instead, resulting in weird stuff.
Somehow I ended up fixing this bug by accident while looking for a bug in
the same area.
Reported-by: kerneloops.org
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: <stable@kernel.org> [2.6.27.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Impact: fix DMA buffer allocation coherency bug in certain configs
This patch fixes swiotlb to use dev->coherent_dma_mask in
swiotlb_alloc_coherent().
coherent_dma_mask is a subset of dma_mask (equal to it most of
the time), enumerating the address range that a given device
is able to DMA to/from in a cache-coherent way.
But currently, swiotlb uses dev->dma_mask in alloc_coherent()
implicitly via address_needs_mapping(), but alloc_coherent is really
supposed to use coherent_dma_mask.
This bug could break drivers that uses smaller coherent_dma_mask than
dma_mask (though the current code works for the majority that use the
same mask for coherent_dma_mask and dma_mask).
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: tony.luck@intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
Clean up based on feedback from Andrew Morton and others:
- change to inline functions instead of macros
- add __init to bootmem method
- add a missing debug check
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: introduce new APIs
We want to deprecate cpumasks on the stack, as we are headed for
gynormous numbers of CPUs. Eventually, we want to head towards an
undefined 'struct cpumask' so they can never be declared on stack.
1) New cpumask functions which take pointers instead of copies.
(cpus_* -> cpumask_*)
2) Several new helpers to reduce requirements for temporary cpumasks
(cpumask_first_and, cpumask_next_and, cpumask_any_and)
3) Helpers for declaring cpumasks on or offstack for large NR_CPUS
(cpumask_var_t, alloc_cpumask_var and free_cpumask_var)
4) 'struct cpumask' for explicitness and to mark new-style code.
5) Make iterator functions stop at nr_cpu_ids (a runtime constant),
not NR_CPUS for time efficiency and for smaller dynamic allocations
in future.
6) cpumask_copy() so we can allocate less than a full cpumask eventually
(for alloc_cpumask_var), and so we can eliminate the 'struct cpumask'
definition eventually.
7) work_on_cpu() helper for doing task on a CPU, rather than saving old
cpumask for current thread and manipulating it.
8) smp_call_function_many() which is smp_call_function_mask() except
taking a cpumask pointer.
Note that this patch simply introduces the new functions and leaves
the obsolescent ones in place. This is to simplify the transition
patches.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
In testing 2.6.28-rc1, I found that passing 'dynamic_printk' on the command
line didn't activate the debug code. The problem is that dynamic_printk_setup()
(which activates the debugging) is being called before dynamic_printk_init() is
called (which initializes infrastructure). Fix this by setting setting the
state to 'DYNAMIC_ENABLED_ALL' in dynamic_printk_setup(), which will also
cause all subsequent modules to have debugging automatically started, which is
probably the behavior we want.
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (31 commits)
ftrace: fix current_tracer error return
tracing: fix a build error on alpha
ftrace: use a real variable for ftrace_nop in x86
tracing/ftrace: make boot tracer select the sched_switch tracer
tracepoint: check if the probe has been registered
asm-generic: define DIE_OOPS in asm-generic
trace: fix printk warning for u64
ftrace: warning in kernel/trace/ftrace.c
ftrace: fix build failure
ftrace, powerpc, sparc64, x86: remove notrace from arch ftrace file
ftrace: remove ftrace hash
ftrace: remove mcount set
ftrace: remove daemon
ftrace: disable dynamic ftrace for all archs that use daemon
ftrace: add ftrace warn on to disable ftrace
ftrace: only have ftrace_kill atomic
ftrace: use probe_kernel
ftrace: comment arch ftrace code
ftrace: return error on failed modified text.
ftrace: dynamic ftrace process only text section
...
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
lockdep: fix irqs on/off ip tracing
lockdep: minor fix for debug_show_all_locks()
x86: restore the old swiotlb alloc_coherent behavior
x86: use GFP_DMA for 24bit coherent_dma_mask
swiotlb: remove panic for alloc_coherent failure
xen: compilation fix of drivers/xen/events.c on IA64
xen: portability clean up and some minor clean up for xencomm.c
xen: don't reload cr3 on suspend
kernel/resource: fix reserve_region_with_split() section mismatch
printk: remove unused code from kernel/printk.c
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (21 commits)
[SCSI] sd: fix computation of the full size of the device
[SCSI] lib: string_get_size(): don't hang on zero; no decimals on exact
[SCSI] sun3x_esp: Convert && to ||
[SCSI] sd: remove command-size switching code
[SCSI] 3w-9xxx: remove unnecessary local_irq_save/restore for scsi sg copy API
[SCSI] 3w-xxxx: remove unnecessary local_irq_save/restore for scsi sg copy API
[SCSI] fix netlink kernel-doc
[SCSI] sd: Fix handling of NO_SENSE check condition
[SCSI] export busy state via q->lld_busy_fn()
[SCSI] refactor sdev/starget/shost busy checking
[SCSI] mptfusion: Increase scsi-timeouts, similariy to the LSI 4.x driver.
[SCSI] aic7xxx: Take the LED out of diagnostic mode on PM resume
[SCSI] aic79xx: user visible misuse wrong SI units (not disk size!)
[SCSI] ipr: use memory_read_from_buffer()
[SCSI] aic79xx: fix shadowed variables
[SCSI] aic79xx: fix shadowed variables, add statics
[SCSI] aic7xxx: update *_shipped files
[SCSI] aic7xxx: update .reg files
[SCSI] aic7xxx: introduce "dont_generate_debug_code" keyword in aicasm parser
[SCSI] scsi_dh: Initialize path state to be passive when path is not owned
...
swiotlb_alloc_coherent calls panic() when allocated swiotlb pages is
not fit for a device's dma mask. However, alloc_coherent failure is
not a disaster at all. AFAIK, none of other x86 and IA64 IOMMU
implementations don't crash in case of alloc_coherent failure.
There are some drivers that don't check alloc_coherent failure but not
many (about ten and I've already started to fix some of
them). alloc_coherent returns NULL in case of failure so it's likely
that these guilty drivers crash immediately. So swiotlb doesn't need
to call panic() just for them.
Reported-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Tested-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
We would hang forever when passing a zero to string_get_size().
Furthermore, string_get_size() would produce decimals on a value small
enough to be exact. Finally, a few formatting issues are inconsistent
with standard SI style guidelines.
- If the value is less than the divisor, skip the entire rounding
step. This prints out all small values including zero as integers,
without decimals.
- Add a space between the value and the symbol for the unit,
consistent with standard SI practice.
- Lower case k in kB since we are talking about powers of 10.
- Finally, change "int" to "unsigned int" in one place to shut up a
gcc warning when compiling the code out-of-kernel for testing.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
* 'for-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/dvrabel/uwb: (47 commits)
uwb: wrong sizeof argument in mac address compare
uwb: don't use printk_ratelimit() so often
uwb: use kcalloc where appropriate
uwb: use time_after() when purging stale beacons
uwb: add credits for the original developers of the UWB/WUSB/WLP subsystems
uwb: add entries in the MAINTAINERS file
uwb: depend on EXPERIMENTAL
wusb: wusb-cbaf (CBA driver) sysfs ABI simplification
uwb: document UWB and WUSB sysfs files
uwb: add symlinks in sysfs between radio controllers and PALs
uwb: dont tranmit identification IEs
uwb: i1480/GUWA100U: fix firmware download issues
uwb: i1480: remove MAC/PHY information checking function
uwb: add Intel i1480 HWA to the UWB RC quirk table
uwb: disable command/event filtering for D-Link DUB-1210
uwb: initialize the debug sub-system
uwb: Fix handling IEs with empty IE data in uwb_est_get_size()
wusb: fix bmRequestType for Abort RPipe request
wusb: fix error path for wusb_set_dev_addr()
wusb: add HWA host controller driver
...
Due to confusion between the ftrace infrastructure and the gcc profiling
tracer "ftrace", this patch renames the config options from FTRACE to
FUNCTION_TRACER. The other two names that are offspring from FTRACE
DYNAMIC_FTRACE and FTRACE_MCOUNT_RECORD will stay the same.
This patch was generated mostly by script, and partially by hand.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add a %pR option to the kernel vsnprintf that prints the range of
addresses inside a struct resource passed by pointer.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
bitmap_scnprintf_len() is not used now, so we remove it.
Otherwise we have to maintain it and make its return
value always equal to bitmap_scnprintf()'s return value.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Paul Menage <menage@google.com>
Cc: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
CONFIG_DEBUG_BLOCK_EXT_DEVT can break booting even on some modern
distros. Add BIG FAT WARNING to keep people at a safe distance.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Open-code them rather than using defining macros. The function bodies are now
next to their kerneldoc comments as a bonus.
Add casts to the signed cases as they call into the unsigned versions.
Avoids the sparse warnings:
lib/vsprintf.c:249:1: warning: incorrect type in argument 3 (different signedness)
lib/vsprintf.c:249:1: expected unsigned long *res
lib/vsprintf.c:249:1: got long *res
lib/vsprintf.c:249:1: warning: incorrect type in argument 3 (different signedness)
lib/vsprintf.c:249:1: expected unsigned long *res
lib/vsprintf.c:249:1: got long *res
lib/vsprintf.c:251:1: warning: incorrect type in argument 3 (different signedness)
lib/vsprintf.c:251:1: expected unsigned long long *res
lib/vsprintf.c:251:1: got long long *res
lib/vsprintf.c:251:1: warning: incorrect type in argument 3 (different signedness)
lib/vsprintf.c:251:1: expected unsigned long long *res
lib/vsprintf.c:251:1: got long long *res
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove extra lines before the EXPORT_SYMBOL()s
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The default base is 10 unless there is a leading zero, in which
case the base will be guessed as 8.
The base will only be guesed as 16 when the string starts with '0x'
the third character is a valid hex digit.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (46 commits)
UIO: Fix mapping of logical and virtual memory
UIO: add automata sercos3 pci card support
UIO: Change driver name of uio_pdrv
UIO: Add alignment warnings for uio-mem
Driver core: add bus_sort_breadthfirst() function
NET: convert the phy_device file to use bus_find_device_by_name
kobject: Cleanup kobject_rename and !CONFIG_SYSFS
kobject: Fix kobject_rename and !CONFIG_SYSFS
sysfs: Make dir and name args to sysfs_notify() const
platform: add new device registration helper
sysfs: use ilookup5() instead of ilookup5_nowait()
PNP: create device attributes via default device attributes
Driver core: make bus_find_device_by_name() more robust
usb: turn dev_warn+WARN_ON combos into dev_WARN
debug: use dev_WARN() rather than WARN_ON() in device_pm_add()
debug: Introduce a dev_WARN() function
sysfs: fix deadlock
device model: Do a quickcheck for driver binding before doing an expensive check
Driver core: Fix cleanup in device_create_vargs().
Driver core: Clarify device cleanup.
...
This patch introduces the generic iommu_num_pages function. It can be used by
a given memory area.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Muli Ben-Yehuda <muli@il.ibm.com>
Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add documentation in kerneldoc for new printk format extensions
This patch documents the new %pS/%pF options in printk in kernel doc.
Hope I didn't miss any other extension.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Using "def_bool n" is pointless, simply using bool here appears more
appropriate.
Further, retaining such options that don't have a prompt and aren't
selected by anything seems also at least questionable.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It finally dawned on me what the clean fix to sysfs_rename_dir
calling kobject_set_name is. Move the work into kobject_rename
where it belongs. The callers serialize us anyway so this is
safe.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When looking at kobject_rename I found two bugs with
that exist when sysfs support is disabled in the kernel.
kobject_rename does not change the name on the kobject when
sysfs support is not compiled in.
kobject_rename without locking attempts to check the
validity of a rename operation, which the kobject layer
simply does not have the infrastructure to do.
This patch documents the previously unstated requirement of
kobject_rename that is the responsibility of the caller to
provide mutual exclusion and to be certain that the new_name
for the kobject is valid.
This patch modifies sysfs_rename_dir in !CONFIG_SYSFS case
to call kobject_set_name to actually change the kobject_name.
This patch removes the bogus and misleading check in kobject_rename
that attempts to see if a rename is valid. The check is bogus
because we do not have the proper locking. The check is misleading
because it looks like we can and do perform checking at the kobject
level that we don't.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Base infrastructure to enable per-module debug messages.
I've introduced CONFIG_DYNAMIC_PRINTK_DEBUG, which when enabled centralizes
control of debugging statements on a per-module basis in one /proc file,
currently, <debugfs>/dynamic_printk/modules. When, CONFIG_DYNAMIC_PRINTK_DEBUG,
is not set, debugging statements can still be enabled as before, often by
defining 'DEBUG' for the proper compilation unit. Thus, this patch set has no
affect when CONFIG_DYNAMIC_PRINTK_DEBUG is not set.
The infrastructure currently ties into all pr_debug() and dev_dbg() calls. That
is, if CONFIG_DYNAMIC_PRINTK_DEBUG is set, all pr_debug() and dev_dbg() calls
can be dynamically enabled/disabled on a per-module basis.
Future plans include extending this functionality to subsystems, that define
their own debug levels and flags.
Usage:
Dynamic debugging is controlled by the debugfs file,
<debugfs>/dynamic_printk/modules. This file contains a list of the modules that
can be enabled. The format of the file is as follows:
<module_name> <enabled=0/1>
.
.
.
<module_name> : Name of the module in which the debug call resides
<enabled=0/1> : whether the messages are enabled or not
For example:
snd_hda_intel enabled=0
fixup enabled=1
driver enabled=0
Enable a module:
$echo "set enabled=1 <module_name>" > dynamic_printk/modules
Disable a module:
$echo "set enabled=0 <module_name>" > dynamic_printk/modules
Enable all modules:
$echo "set enabled=1 all" > dynamic_printk/modules
Disable all modules:
$echo "set enabled=0 all" > dynamic_printk/modules
Finally, passing "dynamic_printk" at the command line enables
debugging for all modules. This mode can be turned off via the above
disable command.
[gkh: minor cleanups and tweaks to make the build work quietly]
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This is a much better version of a previous patch to make the parser
tables constant. Rather than changing the typedef, we put the "const" in
all the various places where its required, allowing the __initconst
exception for nfsroot which was the cause of the previous trouble.
This was posted for review some time ago and I believe its been in -mm
since then.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: Alexander Viro <aviro@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (43 commits)
ext4: Rename ext4dev to ext4
ext4: Avoid double dirtying of super block in ext4_put_super()
Update ext4 MAINTAINERS file
Hook ext4 to the vfs fiemap interface.
generic block based fiemap implementation
ocfs2: fiemap support
vfs: vfs-level fiemap interface
ext4: fix xattr deadlock
jbd2: Fix buffer head leak when writing the commit block
ext4: Add debugging markers that can be used by systemtap
jbd2: abort instead of waiting for nonexistent transaction
ext4: fix initialization of UNINIT bitmap blocks
ext4: Remove old legacy block allocator
ext4: Use readahead when reading an inode from the inode table
ext4: Improve the documentation for ext4's /proc tunables
ext4: Combine proc file handling into a single set of functions
ext4: move /proc setup and teardown out of mballoc.c
ext4: Don't use 'struct dentry' for internal lookups
ext4/jbd2: Avoid WARN() messages when failing to write to the superblock
ext4: use percpu data structures for lg_prealloc_list
...
* 'x86-v28-for-linus-phase3-B' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (74 commits)
AMD IOMMU: use iommu_device_max_index, fix
AMD IOMMU: use iommu_device_max_index
x86: add PCI IDs for AMD Barcelona PCI devices
x86/iommu: use __GFP_ZERO instead of memset for GART
x86/iommu: convert GART need_flush to bool
x86/iommu: make GART driver checkpatch clean
x86 gart: remove unnecessary initialization
x86: restore old GART alloc_coherent behavior
revert "x86: make GART to respect device's dma_mask about virtual mappings"
x86: export pci-nommu's alloc_coherent
iommu: remove fullflush and nofullflush in IOMMU generic option
x86: remove set_bit_string()
iommu: export iommu_area_reserve helper function
AMD IOMMU: use coherent_dma_mask in alloc_coherent
add AMD IOMMU tree to MAINTAINERS file
AMD IOMMU: use cmd_buf_size when freeing the command buffer
AMD IOMMU: calculate IVHD size with a function
AMD IOMMU: remove unnecessary cast to u64 in the init code
AMD IOMMU: free domain bitmap with its allocation order
AMD IOMMU: simplify dma_mask_to_pages
...
* 'rcu-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (21 commits)
rcu: RCU-based detection of stalled CPUs for Classic RCU, fix
rcu: RCU-based detection of stalled CPUs for Classic RCU
rcu: add rcu_read_lock_sched() / rcu_read_unlock_sched()
rcu: fix sparse shadowed variable warning
doc/RCU: fix pseudocode in rcuref.txt
rcuclassic: fix compiler warning
rcu: use irq-safe locks
rcuclassic: fix compilation NG
rcu: fix locking cleanup fallout
rcu: remove redundant ACCESS_ONCE definition from rcupreempt.c
rcu: fix classic RCU locking cleanup lockdep problem
rcu: trace fix possible mem-leak
rcu: just rename call_rcu_bh instead of making it a macro
rcu: remove list_for_each_rcu()
rcu: fixes to include/linux/rcupreempt.h
rcu: classic RCU locking and memory-barrier cleanups
rcu: prevent console flood when one CPU sees another AWOL via RCU
rcu, debug: detect stalled grace periods, cleanups
rcu, debug: detect stalled grace periods
rcu classic: new algorithm for callbacks-processing(v2)
...
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (37 commits)
[SCSI] zfcp: fix double dbf id usage
[SCSI] zfcp: wait on SCSI work to be finished before proceeding with init dev
[SCSI] zfcp: fix erp list usage without using locks
[SCSI] zfcp: prevent fc_remote_port_delete calls for unregistered rport
[SCSI] zfcp: fix deadlock caused by shared work queue tasks
[SCSI] zfcp: put threshold data in hba trace
[SCSI] zfcp: Simplify zfcp data structures
[SCSI] zfcp: Simplify get_adapter_by_busid
[SCSI] zfcp: remove all typedefs and replace them with standards
[SCSI] zfcp: attach and release SAN nameserver port on demand
[SCSI] zfcp: remove unused references, declarations and flags
[SCSI] zfcp: Update message with input from review
[SCSI] zfcp: add queue_full sysfs attribute
[SCSI] scsi_dh: suppress comparison warning
[SCSI] scsi_dh: add Dell product information into rdac device handler
[SCSI] qla2xxx: remove the unused SCSI_QLOGIC_FC_FIRMWARE option
[SCSI] qla2xxx: fix printk format warnings
[SCSI] qla2xxx: Update version number to 8.02.01-k8.
[SCSI] qla2xxx: Ignore payload reserved-bits during RSCN processing.
[SCSI] qla2xxx: Additional residual-count corrections during UNDERRUN handling.
...
Only works for the generic request timer handling. Allows one to
sporadically ignore request completions, thus exercising the timeout
handling.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Ian Campbell