Peter Zijlstra [Wed, 3 Jun 2009 12:01:36 +0000 (14:01 +0200)]
perf_counter: Fix race in counter initialization
We need the PID namespace and counter ID available when the
counter overflows and we need to generate a sample event.
[ Impact: fix kernel crash with high-frequency sampling ]
Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
[ fixed a further crash and cleaned up the initialization a bit ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Wed, 3 Jun 2009 10:37:36 +0000 (12:37 +0200)]
perf report: Fix comm sorting
Since we can (and do) change comm strings during the collection
phase, we cannot actually sort on them to build the histogram.
Therefore add an (optional) third sorting phase to collapse the
histrogram.
Comm sorting now builds the histrogram on threads and then in
the collapse phase collects all threads with the same comm.
This collapsed histogram is then reversed and sorted on events.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
When using interrupting counters and limited (non-interrupting)
counters at the same time, it's possible that we get an
interrupt in write_mmcr0() after writing MMCR0 but before we
have set up the counters using limited PMCs. What happens then
is that we get into perf_counter_interrupt() with
counter->hw.idx = 0 for the limited counters, leading to the
"oops trying to read PMC0" error message being printed.
This fixes the problem by making perf_counter_interrupt()
robust against counter->hw.idx being zero (the counter is just
ignored in that case) and also by changing write_mmcr0() to
write MMCR0 initially with the counter overflow interrupt
enable bits masked (set to 0). If the MMCR0 value requested by
the caller has either of those bits set, we write MMCR0 again
with the requested value of those bits after setting up the
limited counters properly.
Signed-off-by: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: John Kacur <jkacur@redhat.com> Cc: Stephane Eranian <eranian@googlemail.com>
LKML-Reference: <18982.17684.138182.954599@cargo.ozlabs.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Paul Mackerras [Wed, 3 Jun 2009 09:38:58 +0000 (19:38 +1000)]
perf_counter: powerpc: Fix event alternative code generation on POWER5/5+
Commit ef923214 ("perf_counter: powerpc: use u64 for event
codes internally") introduced a bug where the return value from
function find_alternative_bdecode gets put into a u64 variable
and later tested to see if it is < 0. The effect is that we
get extra, bogus event code alternatives on POWER5 and POWER5+,
leading to error messages such as "oops compute_mmcr failed"
being printed and counters not counting properly.
This fixes it by using s64 for the return type of
find_alternative_bdecode and for the local variable that the
caller puts the value in. It also makes the event argument a
u64 on POWER5+ for consistency.
Signed-off-by: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: John Kacur <jkacur@redhat.com> Cc: Stephane Eranian <eranian@googlemail.com>
LKML-Reference: <18982.17586.666132.90983@cargo.ozlabs.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
PLT, the Program Linking Table, is used with the dynamic linker to
allow PIC code in executables and shared objects to figure out
where functions are in other shared objects.
It is one of the sources of unknown/unresolved symbols - this patch
does what binutils figures out when you ask it to disassembly.
(objdump -S)
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: John Kacur <jkacur@redhat.com> Cc: Stephane Eranian <eranian@googlemail.com>
LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Tue, 2 Jun 2009 21:43:11 +0000 (23:43 +0200)]
perf record: Print out the number of events captured
It makes sense to inform the user about how many events
perf record has written - so that the sufficiency of
profiling coverage and intensity can be determined at
a glance.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Tue, 2 Jun 2009 21:24:45 +0000 (23:24 +0200)]
perf report: Print more info instead of <unknown> entries
Sometimes we still fail to find a DSO or look up a symbol,
print out the raw information in this case (which an help
debug the problem), instead of a not very helpful <unknown>
string.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Tue, 2 Jun 2009 14:08:20 +0000 (16:08 +0200)]
perf_counter: x86: Emulate longer sample periods
Do as Power already does, emulate sample periods up to 2^63-1 by
composing them of smaller values limited by hardware capabilities.
Only once we wrap the software period do we generate an overflow
event.
Just 10 lines of new code.
Reported-by: Stephane Eranian <eranian@googlemail.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Tue, 2 Jun 2009 13:08:15 +0000 (15:08 +0200)]
perf_counter: Add unique counter id
Stephan raised the issue that we currently cannot distinguish between
similar counters within a group (PERF_RECORD_GROUP uses the config
value as identifier).
Therefore, generate a new ID for each counter using a global u64
sequence counter.
Reported-by: Stephane Eranian <eranian@googlemail.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Paul Mackerras [Mon, 1 Jun 2009 07:53:16 +0000 (17:53 +1000)]
perf_counter: Remove unused prev_state field
This removes the prev_state field of struct perf_counter since
it is now unused. It was only used by the cpu migration
counter, which doesn't use it any more.
Signed-off-by: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <18979.35052.915728.626374@cargo.ozlabs.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Paul Mackerras [Mon, 1 Jun 2009 07:52:30 +0000 (17:52 +1000)]
perf_counter: Fix cpu migration counter
This fixes the cpu migration software counter to count
correctly even when contexts get swapped from one task to
another. Previously the cpu migration counts reported by perf
stat were bogus, ranging from negative to several thousand for
a single "lat_ctx 2 8 32" run. With this patch the cpu
migration count reported for "lat_ctx 2 8 32" is almost always
between 35 and 44.
This fixes the problem by adding a call into the perf_counter
code from set_task_cpu when tasks are migrated. This enables
us to use the generic swcounter code (with some modifications)
for the cpu migration counter.
This modifies the swcounter code to allow a NULL regs pointer
to be passed in to perf_swcounter_ctx_event() etc. The cpu
migration counter does this because there isn't necessarily a
pt_regs struct for the task available. In this case, the
counter will not have interrupt capability - but the migration
counter didn't have interrupt capability before, so this is no
loss.
Signed-off-by: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <18979.35006.819769.416327@cargo.ozlabs.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Paul Mackerras [Tue, 2 Jun 2009 11:05:16 +0000 (21:05 +1000)]
perf_counter: Initialize per-cpu context earlier on cpu up
This arranges for perf_counter's notifier for cpu hotplug
operations to be called earlier than the migration notifier in
sched.c by increasing its priority to 20, compared to the 10
for the migration notifier. The reason for doing this is that
a subsequent commit to convert the cpu migration counter to use
the generic swcounter infrastructure will add a call into the
perf_counter subsystem when tasks get migrated. Therefore the
perf_counter subsystem needs a chance to initialize its per-cpu
data for the new cpu before it can get called from the
migration code.
This also adds a comment to the migration notifier noting that
its priority needs to be lower than that of the perf_counter
notifier.
Signed-off-by: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <18981.1900.792795.836858@cargo.ozlabs.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Mike Galbraith [Tue, 2 Jun 2009 09:04:44 +0000 (11:04 +0200)]
perf_counter tools: Fix uninitialized variable in perf-report.c
# make prefix=/usr/local V=1
gcc -o builtin-report.o -c -O2 -ggdb3 -Wall -Werror -Wstrict-prototypes -Wmissing-declarations -Wmissing-prototypes -std=gnu99 -Wdeclaration-after-statement -DSHA1_HEADER='<openssl/sha.h>' builtin-report.c
cc1: warnings being treated as errors
builtin-report.c: In function ‘__cmd_report’:
builtin-report.c:626: error: ‘cwdlen’ may be used uninitialized in this function
Signed-off-by: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <new-submission>
Mike Galbraith [Tue, 2 Jun 2009 08:17:34 +0000 (10:17 +0200)]
perf_counter tools: Cleanup Makefile
We currently build perf-stat/record etc, only to do nothing
with them. We also install the perf binary in two places,
$prefix/bin and $perfexec_instdir, which appears to be for
binaries which perf would exec were a command not linked in.
Correct this, and comment out broken/incomplete targets dist
and coverage.
Signed-off-by: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
[acme@emilia ~]$ perf
perf: /lib64/libc.so.6: version `GLIBC_2.7' not found (required by perf)
[acme@emilia ~]$ nm `which perf` | grep GLIBC_2\.7
U __isoc99_sscanf@@GLIBC_2.7
[acme@emilia ~]$
The most commonly used perf commands are:
record Run a command and record its profile into perf.data
report Read perf.data (created by perf record) and display the
profile
stat Run a command and gather performance counter statistics
top Run a command and profile it
See 'perf help COMMAND' for more information on a specific command.
[acme@emilia ~]$ nm `which perf` | grep GLIBC_2\.7
[acme@emilia ~]$
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <20090601205019.GA7805@ghostprotocols.net> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Paul Mackerras [Mon, 1 Jun 2009 07:49:14 +0000 (17:49 +1000)]
perf_counter: Allow software counters to count while task is not running
This changes perf_swcounter_match() so that per-task software
counters can count events that occur while their associated
task is not running. This will allow us to use the generic
software counter code for counting task migrations, which can
occur while the task is not scheduled in.
To do this, we have to distinguish between the situations where
the counter is inactive because its task has been scheduled
out, and those where the counter is inactive because it is part
of a group that was not able to go on the PMU. In the former
case we want the counter to count, but not in the latter case.
If the context is active, we have the latter case. If the
context is inactive then we need to know whether the counter
was counting when the context was last active, which we can
determine by comparing its ->tstamp_stopped timestamp with the
context's timestamp.
This also folds three checks in perf_swcounter_match, checking
perf_event_raw(), perf_event_type() and perf_event_id()
individually, into a single 64-bit comparison on
counter->hw_event.config, as an optimization.
Signed-off-by: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <18979.34810.259718.955621@cargo.ozlabs.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Paul Mackerras [Mon, 1 Jun 2009 07:48:12 +0000 (17:48 +1000)]
perf_counter: Provide functions for locking and pinning the context for a task
This abstracts out the code for locking the context associated
with a task. Because the context might get transferred from
one task to another concurrently, we have to check after
locking the context that it is still the right context for the
task and retry if not. This was open-coded in
find_get_context() and perf_counter_init_task().
This adds a further function for pinning the context for a
task, i.e. marking it so it can't be transferred to another
task. This adds a 'pin_count' field to struct
perf_counter_context to indicate that a context is pinned,
instead of the previous method of setting the parent_gen count
to all 1s. Pinning the context with a pin_count is easier to
undo and doesn't require saving the parent_gen value. This
also adds a perf_unpin_context() to undo the effect of
perf_pin_task_context() and changes perf_counter_init_task to
use it.
Signed-off-by: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <18979.34748.755674.596386@cargo.ozlabs.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Sun, 31 May 2009 20:09:49 +0000 (22:09 +0200)]
perf_counter tools: Fix unknown command help text
Arjan reported this error when entering an unknown command to perf:
$ perf start
fatal: Uh oh. Your system reports no Git commands at all.
The Git code expects there to be perf-* commands - but since Perf
is a 'pure' utility with no dash commands anymore, this old assumption
of Git does not hold anymore. Remove that error check.
Reported-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Fix various errors in the Documentation/perf*.txt description as well.
Also fix a bug in builtin-help: we'd map 'perf help top' to 'perftop'
if only the 'perf' binary is in the default PATH - confusing the manpage
logic. I dont fully understand why Git did it this way - but i suppose
it's a migration artifact from their migration from standalone git-xyz
commands to 'git xyz' commands. The perf tools were always using the
modern form so it's not an issue there.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
We need to protect the active_symbols list as two threads change it:
the main thread adding entries to the head and the display thread
decaying entries from any place in the list.
Also related: take a snapshot of syme->count[0] before using it to
calculate the weight and to show the same number used in this calc when
displaying the symbol usage.
Reported-by: Mike Galbraith <efault@gmx.de> Tested-by: Mike Galbraith <efault@gmx.de> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <20090529200307.GR4747@ghostprotocols.net> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6:
Revert "USB: Correct Makefile to make isp1760 buildable"
usb-serial: fix crash when sub-driver updates firmware
USB: isp1760: urb_dequeue doesn't always find the urbs
USB: Yet another Conexant Clone to add to cdc-acm.c
USB: atmel_usb_udc: Use kzalloc() to allocate ep structures
USB: atmel-usba-udc : fix control out requests.
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6:
Driver Core: do not oops when driver_unregister() is called for unregistered drivers
sysfs: file.c: use create_singlethread_workqueue()
Linus Torvalds [Fri, 29 May 2009 15:49:09 +0000 (08:49 -0700)]
Merge branch 'for-2.6.30' of git://linux-nfs.org/~bfields/linux
* 'for-2.6.30' of git://linux-nfs.org/~bfields/linux:
svcrdma: dma unmap the correct length for the RPCRDMA header page.
nfsd: Revert "svcrpc: take advantage of tcp autotuning"
nfsd: fix hung up of nfs client while sync write data to nfs server
Linus Torvalds [Fri, 29 May 2009 15:48:25 +0000 (08:48 -0700)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: libps2 - better handle bad scheduler decisions
Input: usb1400_ts - fix access to "device data" in resume function
Input: multitouch - augment event semantics documentation
Input: multitouch - add tracking ID to the protocol
Linus Torvalds [Fri, 29 May 2009 15:48:13 +0000 (08:48 -0700)]
Merge branch 'drm-intel-next' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel
* 'drm-intel-next' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel:
i915: Set object to gtt domain when faulting it back in
drm/i915: Apply a big hammer to 865 GEM object CPU cache flushing.
drm/i915: Fix tiling pitch handling on 8xx.
Linus Torvalds [Fri, 29 May 2009 15:47:53 +0000 (08:47 -0700)]
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:
ALSA: hda - Compaq Presario CQ60 patching for Conexant
sound: usb-audio: make the MotU Fastlane work again
ALSA: Enable PCM hw_ptr_jiffies check only in xrun_debug mode
ALSA: Fix invalid jiffies check after pause
Alan Cox [Thu, 28 May 2009 13:01:35 +0000 (14:01 +0100)]
8250: Fix oops from setserial
If you setserial a port which has never been initialised we change the type
but don't update the I/O method pointers. The same problem is true if you
change the io type of a port - but nobody ever does that so nobody noticed!
Remember the old type and when attaching if the type has changed reload the
port accessor pointers. We can't do it blindly as some 8250 drivers load custom
accessors and we must not stomp those.
Tested-by: Victor Seryodkin <vvscore@gmail.com>
Closes-bug: #13367 Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Harry Ciao [Thu, 28 May 2009 21:34:43 +0000 (14:34 -0700)]
edac: AMD8111 & AMD8131 Kconfig fixup
The amd8111_edac.c driver will fail allmodconfig on architectures other
than PPC, introduce Kconfig dependency to avoid this, since both AMD8111
and AMD8131 chips are only adopted on Maple so far.
Signed-off-by: Harry Ciao <qingtao.cao@windriver.com> Cc: Doug Thompson <norsk5@yahoo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
hugetlbfs reserves huge pages but does not fault them at mmap() time to
ensure that future faults succeed. The reservation behaviour differs
depending on whether the mapping was mapped MAP_SHARED or MAP_PRIVATE.
For MAP_SHARED mappings, hugepages are reserved when mmap() is first
called and are tracked based on information associated with the inode.
Other processes mapping MAP_SHARED use the same reservation. MAP_PRIVATE
track the reservations based on the VMA created as part of the mmap()
operation. Each process mapping MAP_PRIVATE must make its own
reservation.
hugetlbfs currently checks if a VMA is MAP_SHARED with the VM_SHARED flag
and not VM_MAYSHARE. For file-backed mappings, such as hugetlbfs,
VM_SHARED is set only if the mapping is MAP_SHARED and the file was opened
read-write. If a shared memory mapping was mapped shared-read-write for
populating of data and mapped shared-read-only by other processes, then
hugetlbfs would account for the mapping as if it was MAP_PRIVATE. This
causes processes to fail to map the file MAP_SHARED even though it should
succeed as the reservation is there.
This patch alters mm/hugetlb.c and replaces VM_SHARED with VM_MAYSHARE
when the intent of the code was to check whether the VMA was mapped
MAP_SHARED or MAP_PRIVATE.
Signed-off-by: Mel Gorman <mel@csn.ul.ie> Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk> Cc: Ingo Molnar <mingo@elte.hu> Cc: <stable@kernel.org> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: <starlight@binnacle.cx> Cc: Eric B Munson <ebmunson@us.ibm.com> Cc: Adam Litke <agl@us.ibm.com> Cc: Andy Whitcroft <apw@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On x86 and x86-64, it is possible that page tables are shared beween
shared mappings backed by hugetlbfs. As part of this,
page_table_shareable() checks a pair of vma->vm_flags and they must match
if they are to be shared. All VMA flags are taken into account, including
VM_LOCKED.
The problem is that VM_LOCKED is cleared on fork(). When a process with a
shared memory segment forks() to exec() a helper, there will be shared
VMAs with different flags. The impact is that the shared segment is
sometimes considered shareable and other times not, depending on what
process is checking.
What happens is that the segment page tables are being shared but the
count is inaccurate depending on the ordering of events. As the page
tables are freed with put_page(), bad pmd's are found when some of the
children exit. The hugepage counters also get corrupted and the Total and
Free count will no longer match even when all the hugepage-backed regions
are freed. This requires a reboot of the machine to "fix".
This patch addresses the problem by comparing all flags except VM_LOCKED
when deciding if pagetables should be shared or not for hugetlbfs-backed
mapping.
Signed-off-by: Mel Gorman <mel@csn.ul.ie> Acked-by: Hugh Dickins <hugh.dickins@tiscali.co.uk> Cc: Ingo Molnar <mingo@elte.hu> Cc: <stable@kernel.org> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: <starlight@binnacle.cx> Cc: Eric B Munson <ebmunson@us.ibm.com> Cc: Adam Litke <agl@us.ibm.com> Cc: Andy Whitcroft <apw@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Nicolas Ferre [Thu, 28 May 2009 21:34:36 +0000 (14:34 -0700)]
atmel_lcdfb: correct fifo size for some products
Remove wrong fifo size definition for some AT91 products.
Due to a misunderstanding of some AT91 datasheets, a fifo size of 2048
(words) has been introduced by mistake. In fact, all products (AT91/AT32)
are sharing the same fifo size of 512 words.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Andrew Victor <avictor.za@gmail.com> Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Marek Szyprowski [Thu, 28 May 2009 21:34:35 +0000 (14:34 -0700)]
S3C-fb: PM fix
Correctly restore the FrameBuffer register state in the resume function.
Reviewed-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Ben Dooks <ben-linux@fluff.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/parport/parport_gsc.c:356: warning: format '%lx' expects type
'long unsigned int', but argument 2 has type 'resource_size_t'
[akpm@linux-foundation.org: fix it to handle u64's] Signed-off-by: Alexander Beregalov <a.beregalov@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Oskar Schirmer [Thu, 28 May 2009 21:34:31 +0000 (14:34 -0700)]
flat: fix data sections alignment
The flat loader uses an architecture's flat_stack_align() to align the
stack but assumes word-alignment is enough for the data sections.
However, on the Xtensa S6000 we have registers up to 128bit width
which can be used from userspace and therefor need userspace stack and
data-section alignment of at least this size.
This patch drops flat_stack_align() and uses the same alignment that
is required for slab caches, ARCH_SLAB_MINALIGN, or wordsize if it's
not defined by the architecture.
It also fixes m32r which was obviously kaput, aligning an
uninitialized stack entry instead of the stack pointer.
[akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Oskar Schirmer <os@emlix.com> Cc: David Howells <dhowells@redhat.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Bryan Wu <cooloney@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Paul Mundt <lethal@linux-sh.org> Cc: Greg Ungerer <gerg@uclinux.org> Signed-off-by: Johannes Weiner <jw@emlix.com> Acked-by: Mike Frysinger <vapier.adi@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
memcg: fix deadlock between lock_page_cgroup and mapping tree_lock
mapping->tree_lock can be acquired from interrupt context. Then,
following dead lock can occur.
Assume "A" as a page.
CPU0:
lock_page_cgroup(A)
interrupted
-> take mapping->tree_lock.
CPU1:
take mapping->tree_lock
-> lock_page_cgroup(A)
This patch tries to fix above deadlock by moving memcg's hook to out of
mapping->tree_lock. charge/uncharge of pagecache/swapcache is protected
by page lock, not tree_lock.
After this patch, lock_page_cgroup() is not called under mapping->tree_lock.
Then, proc_pident_instantiate should return ENOENT too when racing against
exit(2) occur.
EINAL has two bad reason.
- it implies caller is wrong. bad the race isn't caller's mistake.
- man 2 open don't explain EINVAL. user often don't handle it.
Note: Other proc_pid_make_inode() caller already use ENOENT properly.
Acked-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Rientjes [Thu, 28 May 2009 21:34:19 +0000 (14:34 -0700)]
oom: fix possible oom_dump_tasks NULL pointer
When /proc/sys/vm/oom_dump_tasks is enabled, it is possible to get a NULL
pointer for tasks that have detached mm's since task_lock() is not held
during the tasklist scan. Add the task_lock().
Acked-by: Nick Piggin <npiggin@suse.de> Acked-by: Mel Gorman <mel@csn.ul.ie> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Peter Zijlstra [Fri, 29 May 2009 12:25:58 +0000 (14:25 +0200)]
perf_counter: Ammend cleanup in fork() fail
When fork() fails we cannot use perf_counter_exit_task() since that
assumes to operate on current. Write a new helper that cleans up
unused/clean contexts.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Fri, 29 May 2009 12:51:57 +0000 (14:51 +0200)]
perf_counter: Clean up task_ctx vs interrupts
Remove the local_irq_save() etc.. in routines that are smp function
calls, or have IRQs disabled by other means.
Then change the COMM, MMAP, and swcounter context iteration to
current->perf_counter_ctxp and RCU, since it really doesn't matter
which context they iterate, they're all folded.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Fri, 29 May 2009 12:25:58 +0000 (14:25 +0200)]
perf_counter: Fix COMM and MMAP events for cpu wide counters
Commit a63eaf34ae6 ("perf_counter: Dynamically allocate tasks'
perf_counter_context struct") broke COMM and MMAP notification for
cpu wide counters by dropping out early if there was no task context,
thereby also not iterating the cpu context.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Joakim Tjernlund [Thu, 28 May 2009 15:43:59 +0000 (17:43 +0200)]
jffs2: Fix corruption when flash erase/write failure
Erase errors such as:
"Newly-erased block contained word 0xa4ef223e at offset 0x0296a014"
and failure to write the clean marker,
moves the offending erase block to erasing list before calling
jffs2_erase_failed(). This is bad as jffs2_erase_failed() will
also move the block to the bad_list, but is now moving the
wrong block, causing FS corruption.
Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Vladimir Barinov [Thu, 23 Apr 2009 11:47:22 +0000 (15:47 +0400)]
mtd: MXC NAND driver fixes (v5)
The following patch fixes:
- re-initialization of host->col_addr which is used as byte index
between the successive READID flash commands.
- compile error when CONFIG_PM is enabled
- pass on the error code from clk_get()
- return -ENOMEM in case of failed ioremap()
- pass on the return value of platform_driver_probe() directly
- remove excessive printk
- let command line partition table parsing with mxc_nand name.
The cmd_line parsing is done via <mtd-id> name that differs
from mxc_nand by default and looks like "NAND 256MiB 1,8V 8-bit"
Signed-off-by: Vladimir Barinov <vbarinov@embeddedalley.com> Signed-off-by: Lothar Wassmann <LW@KARO-electronics.de> Acked-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Peter Zijlstra pointed out that under some circumstances, we can take
the mutex in a context or a counter and then swap that context or
counter to another task, potentially leading to lock order inversions
or the mutexes not protecting what they are supposed to protect.
This fixes the problem by making sure that we never take a mutex in a
context or counter which could get swapped to another task. Most of
the cases where we take a mutex is on a top-level counter or context,
i.e. a counter which has an fd associated with it or a context that
contains such a counter. This adds WARN_ON_ONCE statements to verify
that.
The two cases where we need to take the mutex on a context that is a
clone of another are in perf_counter_exit_task and
perf_counter_init_task. The perf_counter_exit_task case is solved by
uncloning the context before starting to remove the counters from it.
The perf_counter_init_task is a little trickier; we temporarily
disable context swapping for the parent (forking) task by setting its
ctx->parent_gen to the all-1s value after locking the context, if it
is a cloned context, and restore the ctx->parent_gen value at the end
if the context didn't get uncloned in the meantime.
This also moves the increment of the context generation count to be
within the same critical section, protected by the context mutex, that
adds the new counter to the context. That way, taking the mutex is
sufficient to ensure that both the counter list and the generation
count are stable.
[ Impact: fix hangs, races with inherited and PID counters ]
Signed-off-by: Paul Mackerras <paulus@samba.org> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <18975.31580.520676.619896@drongo.ozlabs.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
The advantage of that column is that it is characteristic of the
execution workflow, regardless of runtime. Hence 'hackbench 10'
will look similar to 'hackbench 15' - while the absolute counter
values are very different.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Andrew Morton [Thu, 7 May 2009 19:36:53 +0000 (12:36 -0700)]
sysfs: file.c: use create_singlethread_workqueue()
We don't need a kernel thread per CPU for this application.
Acked-by: Alex Chiang <achiang@hp.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
projects / linux-beck.git / log