Commit graph

468 commits

Author SHA1 Message Date
Linus Torvalds
0429fbc0bd Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
Pull percpu consistent-ops changes from Tejun Heo:
 "Way back, before the current percpu allocator was implemented, static
  and dynamic percpu memory areas were allocated and handled separately
  and had their own accessors.  The distinction has been gone for many
  years now; however, the now duplicate two sets of accessors remained
  with the pointer based ones - this_cpu_*() - evolving various other
  operations over time.  During the process, we also accumulated other
  inconsistent operations.

  This pull request contains Christoph's patches to clean up the
  duplicate accessor situation.  __get_cpu_var() uses are replaced with
  with this_cpu_ptr() and __this_cpu_ptr() with raw_cpu_ptr().

  Unfortunately, the former sometimes is tricky thanks to C being a bit
  messy with the distinction between lvalues and pointers, which led to
  a rather ugly solution for cpumask_var_t involving the introduction of
  this_cpu_cpumask_var_ptr().

  This converts most of the uses but not all.  Christoph will follow up
  with the remaining conversions in this merge window and hopefully
  remove the obsolete accessors"

* 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (38 commits)
  irqchip: Properly fetch the per cpu offset
  percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t -fix
  ia64: sn_nodepda cannot be assigned to after this_cpu conversion. Use __this_cpu_write.
  percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t
  Revert "powerpc: Replace __get_cpu_var uses"
  percpu: Remove __this_cpu_ptr
  clocksource: Replace __this_cpu_ptr with raw_cpu_ptr
  sparc: Replace __get_cpu_var uses
  avr32: Replace __get_cpu_var with __this_cpu_write
  blackfin: Replace __get_cpu_var uses
  tile: Use this_cpu_ptr() for hardware counters
  tile: Replace __get_cpu_var uses
  powerpc: Replace __get_cpu_var uses
  alpha: Replace __get_cpu_var
  ia64: Replace __get_cpu_var uses
  s390: cio driver &__get_cpu_var replacements
  s390: Replace __get_cpu_var uses
  mips: Replace __get_cpu_var uses
  MIPS: Replace __get_cpu_var uses in FPU emulator.
  arm: Replace __this_cpu_ptr with raw_cpu_ptr
  ...
2014-10-15 07:48:18 +02:00
Linus Torvalds
ebf546cc53 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Two leftover fixes from the v3.17 cycle - these will be forwarded to
  stable as well, if they prove problem-free in wider testing as well"

[ Side note: the "fix perf bug in fork()" fix had also come in through
  Andrew's patch-bomb   - Linus ]

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Fix perf bug in fork()
  perf: Fix unclone_ctx() vs. locking
2014-10-13 16:06:09 +02:00
Linus Torvalds
9d9420f120 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
 "Kernel side updates:

   - Fix and enhance poll support (Jiri Olsa)

   - Re-enable inheritance optimization (Jiri Olsa)

   - Enhance Intel memory events support (Stephane Eranian)

   - Refactor the Intel uncore driver to be more maintainable (Zheng
     Yan)

   - Enhance and fix Intel CPU and uncore PMU drivers (Peter Zijlstra,
     Andi Kleen)

   - [ plus various smaller fixes/cleanups ]

  User visible tooling updates:

   - Add +field argument support for --field option, so that one can add
     fields to the default list of fields to show, ie now one can just
     do:

         perf report --fields +pid

     And the pid will appear in addition to the default fields (Jiri
     Olsa)

   - Add +field argument support for --sort option (Jiri Olsa)

   - Honour -w in the report tools (report, top), allowing to specify
     the widths for the histogram entries columns (Namhyung Kim)

   - Properly show submicrosecond times in 'perf kvm stat' (Christian
     Borntraeger)

   - Add beautifier for mremap flags param in 'trace' (Alex Snast)

   - perf script: Allow callchains if any event samples them

   - Don't truncate Intel style addresses in 'annotate' (Alex Converse)

   - Allow profiling when kptr_restrict == 1 for non root users, kernel
     samples will just remain unresolved (Andi Kleen)

   - Allow configuring default options for callchains in config file
     (Namhyung Kim)

   - Support operations for shared futexes.  (Davidlohr Bueso)

   - "perf kvm stat report" improvements by Alexander Yarygin:
       -  Save pid string in opts.target.pid
       -  Enable the target.system_wide flag
       -  Unify the title bar output

   - [ plus lots of other fixes and small improvements.  ]

  Tooling infrastructure changes:

   - Refactor unit and scale function parameters for PMU parsing
     routines (Matt Fleming)

   - Improve DSO long names lookup with rbtree, resulting in great
     speedup for workloads with lots of DSOs (Waiman Long)

   - We were not handling POLLHUP notifications for event file
     descriptors

     Fix it by filtering entries in the events file descriptor array
     after poll() returns, refcounting mmaps so that when the last fd
     pointing to a perf mmap goes away we do the unmap (Arnaldo Carvalho
     de Melo)

   - Intel PT prep work, from Adrian Hunter, including:
       - Let a user specify a PMU event without any config terms
       - Add perf-with-kcore script
       - Let default config be defined for a PMU
       - Add perf_pmu__scan_file()
       - Add a 'perf test' for tracking with sched_switch
       - Add 'flush' callback to scripting API

   - Use ring buffer consume method to look like other tools (Arnaldo
     Carvalho de Melo)

   - hists browser (used in top and report) refactorings, getting rid of
     unused variables and reducing source code size by handling similar
     cases in a fewer functions (Namhyung Kim).

   - Replace thread unsafe strerror() with strerror_r() accross the
     whole tools/perf/ tree (Masami Hiramatsu)

   - Rename ordered_samples to ordered_events and allow setting a queue
     size for ordering events (Jiri Olsa)

   - [ plus lots of fixes, cleanups and other improvements ]"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (198 commits)
  perf/x86: Tone down kernel messages when the PMU check fails in a virtual environment
  perf/x86/intel/uncore: Fix minor race in box set up
  perf record: Fix error message for --filter option not coming after tracepoint
  perf tools: Fix build breakage on arm64 targets
  perf symbols: Improve DSO long names lookup speed with rbtree
  perf symbols: Encapsulate dsos list head into struct dsos
  perf bench futex: Sanitize -q option in requeue
  perf bench futex: Support operations for shared futexes
  perf trace: Fix mmap return address truncation to 32-bit
  perf tools: Refactor unit and scale function parameters
  perf tools: Fix line number in the config file error message
  perf tools: Convert {record,top}.call-graph option to call-graph.record-mode
  perf tools: Introduce perf_callchain_config()
  perf callchain: Move some parser functions to callchain.c
  perf tools: Move callchain config from record_opts to callchain_param
  perf hists browser: Fix callchain print bug on TUI
  perf tools: Use ACCESS_ONCE() instead of volatile cast
  perf tools: Modify error code for when perf_session__new() fails
  perf tools: Fix perf record as non root with kptr_restrict == 1
  perf stat: Fix --per-core on multi socket systems
  ...
2014-10-13 15:58:15 +02:00
Linus Torvalds
b211e9d7c8 Merge branch 'for-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo:
 "Nothing too interesting.  Just a handful of cleanup patches"

* 'for-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  Revert "cgroup: remove redundant variable in cgroup_mount()"
  cgroup: remove redundant variable in cgroup_mount()
  cgroup: fix missing unlock in cgroup_release_agent()
  cgroup: remove CGRP_RELEASABLE flag
  perf/cgroup: Remove perf_put_cgroup()
  cgroup: remove redundant check in cgroup_ino()
  cpuset: simplify proc_cpuset_show()
  cgroup: simplify proc_cgroup_show()
  cgroup: use a per-cgroup work for release agent
  cgroup: remove bogus comments
  cgroup: remove redundant code in cgroup_rmdir()
  cgroup: remove some useless forward declarations
  cgroup: fix a typo in comment.
2014-10-10 07:24:40 -04:00
Peter Zijlstra
9c2b9d30e2 perf: Fix perf bug in fork()
Oleg noticed that a cleanup by Sylvain actually uncovered a bug; by
calling perf_event_free_task() when failing sched_fork() we will not yet
have done the memset() on ->perf_event_ctxp[] and will therefore try and
'free' the inherited contexts, which are still in use by the parent
process.

This is bad and might explain some outstanding fuzzer failures ...

Suggested-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Sylvain 'ythier' Hitier <sylvain.hitier@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Daeseok Youn <daeseok.youn@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Vladimir Davydov <vdavydov@parallels.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20140929101201.GE5430@worktop
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-03 05:41:08 +02:00
Peter Zijlstra
211de6eba8 perf: Fix unclone_ctx() vs. locking
The idiot who did 4a1c0f262f ("perf: Fix lockdep warning on process exit")
forgot to pay attention and fix all similar cases. Do so now.

In particular, unclone_ctx() must be called while holding ctx->lock,
therefore all such sites are broken for the same reason. Pull the
put_ctx() call out from under ctx->lock.

Reported-by: Sasha Levin <sasha.levin@oracle.com>
Probably-also-reported-by: Vince Weaver <vincent.weaver@maine.edu>
Fixes: 4a1c0f262f ("perf: Fix lockdep warning on process exit")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Cong Wang <cwang@twopensource.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140930172308.GI4241@worktop.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-03 05:41:06 +02:00
Peter Zijlstra
6c72e3501d perf: fix perf bug in fork()
Oleg noticed that a cleanup by Sylvain actually uncovered a bug; by
calling perf_event_free_task() when failing sched_fork() we will not yet
have done the memset() on ->perf_event_ctxp[] and will therefore try and
'free' the inherited contexts, which are still in use by the parent
process.  This is bad..

Suggested-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Sylvain 'ythier' Hitier <sylvain.hitier@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-02 16:28:44 -07:00
Jiri Olsa
802c8a61d4 Revert "perf: Do not allow optimized switch for non-cloned events"
This reverts commit 1f9a7268c6.

With the fix of the initial state for the cloned event we now correctly
handle the error described in:

  1f9a7268c6 perf: Do not allow optimized switch for non-cloned events

so we can revert it.

I made an automated test for this, but its not suitable for automated
perf tests framework. It needs to be customized for each machine (the
more cpu the higher numbers for GROUPS/WORKERS/BYTES) and it could take
longer time to hit the issue.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140910143535.GD2409@krava.brq.redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-24 14:48:13 +02:00
Jiri Olsa
1929def9e6 perf: Fix child event initial state setup
Currently we initialize the child event based on the original
parent state. This is wrong, because the original parent event
(and its state) is not related to current fork and also could
be already gone.

We need to initialize the child state based on the immediate
parent event state.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1410520708-19275-2-git-send-email-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-24 14:48:12 +02:00
Jiri Olsa
dc633982ff perf: Do not POLLHUP event if it has children
Currently we return POLLHUP in event polling if the monitored
process is done, but we didn't consider possible children,
that might be still running and producing data.

Before returning POLLHUP making sure that:

   1) the monitored task has exited and that
   2) we don't have any children to monitor

Also adding parent wakeup when the child event is gone.

Suggested-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1410520708-19275-1-git-send-email-jolsa@kernel.org
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-24 14:48:11 +02:00
Zefan Li
4e2ba65068 perf/cgroup: Remove perf_put_cgroup()
Commit 5a17f543ed ("cgroup: improve css_from_dir() into css_tryget_from_dir()")
removed perf_tryget_cgroup(), so let's also remove perf_put_cgroup().

Signed-off-by: Zefan Li <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-09-19 09:17:47 -04:00
Jiri Olsa
c88f209613 perf: Do not check PERF_EVENT_STATE_EXIT on syscall read path
Revert PERF_EVENT_STATE_EXIT check on read syscall path.
It breaks standard way to read counter, which is to open
the counter, wait for the monitored process to die and
read the counter.

Reported-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Stephane Eranian <eranian@google.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: David Ahern <dsahern@gmail.com>
Link: http://lkml.kernel.org/r/20140908143107.GG17728@krava.brq.redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-16 10:30:36 +02:00
Cong Wang
3577af70a2 perf: Fix a race condition in perf_remove_from_context()
We saw a kernel soft lockup in perf_remove_from_context(),
it looks like the `perf` process, when exiting, could not go
out of the retry loop. Meanwhile, the target process was forking
a child. So either the target process should execute the smp
function call to deactive the event (if it was running) or it should
do a context switch which deactives the event.

It seems we optimize out a context switch in perf_event_context_sched_out(),
and what's more important, we still test an obsolete task pointer when
retrying, so no one actually would deactive that event in this situation.
Fix it directly by reloading the task pointer in perf_remove_from_context().

This should cure the above soft lockup.

Signed-off-by: Cong Wang <cwang@twopensource.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/1409696840-843-1-git-send-email-xiyou.wangcong@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-09 06:53:42 +02:00
Andreea-Cristina Bernat
70691d4a0b perf/core: Replace rcu_assign_pointer() with RCU_INIT_POINTER()
The use of "rcu_assign_pointer()" is NULLing out the pointer.
According to RCU_INIT_POINTER()'s block comment:

  "1.   This use of RCU_INIT_POINTER() is NULLing out the pointer"

it is better to use it instead of rcu_assign_pointer() because it has a
smaller overhead.

The following Coccinelle semantic patch was used:
  @@
  @@

  - rcu_assign_pointer
  + RCU_INIT_POINTER
    (..., NULL)

Signed-off-by: Andreea-Cristina Bernat <bernat.ada@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Link: http://lkml.kernel.org/r/20140822132605.GA20130@ada
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-09 06:53:05 +02:00
Andreea-Cristina Bernat
e0455e194a perf/callchain: Replace rcu_assign_pointer() with RCU_INIT_POINTER()
The use of "rcu_assign_pointer()" is NULLing out the pointer.
According to RCU_INIT_POINTER()'s block comment:

 "1.   This use of RCU_INIT_POINTER() is NULLing out the pointer"

it is better to use it instead of rcu_assign_pointer() because it has a
smaller overhead.

 The following Coccinelle semantic patch was used:
 @@
 @@

 - rcu_assign_pointer
 + RCU_INIT_POINTER
   (..., NULL)

Signed-off-by: Andreea-Cristina Bernat <bernat.ada@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: paulmck@linux.vnet.ibm.com
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Link: http://lkml.kernel.org/r/20140822141536.GA32051@ada
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-09 06:53:04 +02:00
Ingo Molnar
bdea534db8 Linux 3.17-rc4
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Merge tag 'v3.17-rc4' into perf/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-09 06:48:07 +02:00
Christoph Lameter
4a32fea9d7 scheduler: Replace __get_cpu_var with this_cpu_ptr
Convert all uses of __get_cpu_var for address calculation to use
this_cpu_ptr instead.

[Uses of __get_cpu_var with cpumask_var_t are no longer
handled by this patch]

Cc: Peter Zijlstra <peterz@infradead.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-08-26 13:45:45 -04:00
Linus Torvalds
44744bb344 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "A kprobes and a perf compat ioctl fix"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Handle compat ioctl
  kprobes: Skip kretprobe hit in NMI context to avoid deadlock
2014-08-24 16:16:55 -07:00
Ingo Molnar
83bc90e115 Merge branch 'linus' into perf/core, to fix conflicts
Conflicts:
	arch/x86/kernel/cpu/perf_event_intel_uncore*.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-24 22:32:24 +02:00
Jiri Olsa
179033b3e0 perf: Add PERF_EVENT_STATE_EXIT state for events with exited task
Adding new perf event state to indicate that the monitored task has
exited.  In this case the event stays alive until the owner task exits
or close the event fd while providing the last data through the read
syscall and ring buffer.

Instead it needs to propagate the error info (monitored task has died)
via poll and read  syscalls by  returning POLLHUP and 0 respectively.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140811120102.GY9918@twins.programming.kicks-ass.net
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-t5y3w8jjx6tfo5w8y6oajsjq@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-08-24 08:11:09 -03:00
Jiri Olsa
61b67684c4 perf: Fix perf_poll to return proper POLLHUP value
Currently perf_poll returns POLL_HUP in case of error, which is wrong,
because poll syscall expects POLLHUP.  The POLL_HUP is meant to be used
for SIGIO state.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140811120102.GY9918@twins.programming.kicks-ass.net
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-0ywfthh4lh65swe15f6w2x2q@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-08-24 08:10:55 -03:00
Pawel Moll
b3f207855f perf: Handle compat ioctl
When running a 32-bit userspace on a 64-bit kernel (eg. i386
application on x86_64 kernel or 32-bit arm userspace on arm64
kernel) some of the perf ioctls must be treated with special
care, as they have a pointer size encoded in the command.

For example, PERF_EVENT_IOC_ID in 32-bit world will be encoded
as 0x80042407, but 64-bit kernel will expect 0x80082407. In
result the ioctl will fail returning -ENOTTY.

This patch solves the problem by adding code fixing up the
size as compat_ioctl file operation.

Reported-by: Drew Richardson <drew.richardson@arm.com>
Signed-off-by: Pawel Moll <pawel.moll@arm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1402671812-9078-1-git-send-email-pawel.moll@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-20 09:42:13 +02:00
Sebastian Andrzej Siewior
e708d7ad80 perf: Do poll_wait() before checking condition in perf_poll()
One should first enqueue to the waitqueue and then check for the
condition. If the condition gets true after mutex_unlock() but before
poll_wait() then we lose it and would have wait for another wakeup.

This has been like this since v2.6.31-rc1 commit c7138f37f9 ("perf_counter:
fix perf_poll()"). Before that it was slightly worse. I guess we get enough
wakeups so if we miss here one it doesn't really matter. It is still a
bad example.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1407159068-1478-1-git-send-email-bigeasy@linutronix.de
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-13 07:51:11 +02:00
Jiri Olsa
fadfe7be6e perf: Add queued work to remove orphaned child events
In cases when the  owner task exits before the workload and the
workload made some forks, all the events stay in until the last
workload process exits. Thats' because each child event holds
parent reference.

We want to release all children events once the parent is gone,
because at that time there's no process to read them anyway, so
they're just eating resources.

This removal  races with process exit, which removes all events
and fork, which clone events.  To be clear of those two, adding
work queue to remove orphaned child for context in case such
event is detected.

Using delayed work queue (with delay == 1), because we queue this
work under perf scheduler callbacks. Normal work queue tries to wake
up the queue process, which deadlocks on rq->lock in this place.

Also preventing clones from abandoned parent event.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1406896382-18404-4-git-send-email-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-13 07:51:04 +02:00
Jiri Olsa
f86977620e perf: Set owner pointer for kernel events
Adding fake EVENT_OWNER_KERNEL owner pointer value for kernel perf
events, so we could distinguish it from user events, which needs
special care in following patch.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1406896382-18404-3-git-send-email-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-13 07:51:03 +02:00
Johannes Weiner
00501b531c mm: memcontrol: rewrite charge API
These patches rework memcg charge lifetime to integrate more naturally
with the lifetime of user pages.  This drastically simplifies the code and
reduces charging and uncharging overhead.  The most expensive part of
charging and uncharging is the page_cgroup bit spinlock, which is removed
entirely after this series.

Here are the top-10 profile entries of a stress test that reads a 128G
sparse file on a freshly booted box, without even a dedicated cgroup (i.e.
 executing in the root memcg).  Before:

    15.36%              cat  [kernel.kallsyms]   [k] copy_user_generic_string
    13.31%              cat  [kernel.kallsyms]   [k] memset
    11.48%              cat  [kernel.kallsyms]   [k] do_mpage_readpage
     4.23%              cat  [kernel.kallsyms]   [k] get_page_from_freelist
     2.38%              cat  [kernel.kallsyms]   [k] put_page
     2.32%              cat  [kernel.kallsyms]   [k] __mem_cgroup_commit_charge
     2.18%          kswapd0  [kernel.kallsyms]   [k] __mem_cgroup_uncharge_common
     1.92%          kswapd0  [kernel.kallsyms]   [k] shrink_page_list
     1.86%              cat  [kernel.kallsyms]   [k] __radix_tree_lookup
     1.62%              cat  [kernel.kallsyms]   [k] __pagevec_lru_add_fn

After:

    15.67%           cat  [kernel.kallsyms]   [k] copy_user_generic_string
    13.48%           cat  [kernel.kallsyms]   [k] memset
    11.42%           cat  [kernel.kallsyms]   [k] do_mpage_readpage
     3.98%           cat  [kernel.kallsyms]   [k] get_page_from_freelist
     2.46%           cat  [kernel.kallsyms]   [k] put_page
     2.13%       kswapd0  [kernel.kallsyms]   [k] shrink_page_list
     1.88%           cat  [kernel.kallsyms]   [k] __radix_tree_lookup
     1.67%           cat  [kernel.kallsyms]   [k] __pagevec_lru_add_fn
     1.39%       kswapd0  [kernel.kallsyms]   [k] free_pcppages_bulk
     1.30%           cat  [kernel.kallsyms]   [k] kfree

As you can see, the memcg footprint has shrunk quite a bit.

   text    data     bss     dec     hex filename
  37970    9892     400   48262    bc86 mm/memcontrol.o.old
  35239    9892     400   45531    b1db mm/memcontrol.o

This patch (of 4):

The memcg charge API charges pages before they are rmapped - i.e.  have an
actual "type" - and so every callsite needs its own set of charge and
uncharge functions to know what type is being operated on.  Worse,
uncharge has to happen from a context that is still type-specific, rather
than at the end of the page's lifetime with exclusive access, and so
requires a lot of synchronization.

Rewrite the charge API to provide a generic set of try_charge(),
commit_charge() and cancel_charge() transaction operations, much like
what's currently done for swap-in:

  mem_cgroup_try_charge() attempts to reserve a charge, reclaiming
  pages from the memcg if necessary.

  mem_cgroup_commit_charge() commits the page to the charge once it
  has a valid page->mapping and PageAnon() reliably tells the type.

  mem_cgroup_cancel_charge() aborts the transaction.

This reduces the charge API and enables subsequent patches to
drastically simplify uncharging.

As pages need to be committed after rmap is established but before they
are added to the LRU, page_add_new_anon_rmap() must stop doing LRU
additions again.  Revive lru_cache_add_active_or_unevictable().

[hughd@google.com: fix shmem_unuse]
[hughd@google.com: Add comments on the private use of -EAGAIN]
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vladimir Davydov <vdavydov@parallels.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-08 15:57:17 -07:00
Ingo Molnar
5030c69755 Linux 3.16-rc7
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Merge tag 'v3.16-rc7' into perf/core, to merge in the latest fixes before applying new changes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-28 10:00:33 +02:00
Linus Torvalds
9dae0a3fc4 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Thomas Gleixner:
 "A bunch of fixes for perf and kprobes:
   - revert a commit that caused a perf group regression
   - silence dmesg spam
   - fix kprobe probing errors on ia64 and ppc64
   - filter kprobe faults from userspace
   - lockdep fix for perf exit path
   - prevent perf #GP in KVM guest
   - correct perf event and filters"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  kprobes: Fix "Failed to find blacklist" probing errors on ia64 and ppc64
  kprobes/x86: Don't try to resolve kprobe faults from userspace
  perf/x86/intel: Avoid spamming kernel log for BTS buffer failure
  perf/x86/intel: Protect LBR and extra_regs against KVM lying
  perf: Fix lockdep warning on process exit
  perf/x86/intel/uncore: Fix SNB-EP/IVT Cbox filter mappings
  perf/x86/intel: Use proper dTLB-load-misses event on IvyBridge
  perf: Revert ("perf: Always destroy groups on exit")
2014-07-27 09:57:16 -07:00
Linus Torvalds
d14aef3872 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Tooling fixes and an Intel PMU driver fixlet"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Do not allow optimized switch for non-cloned events
  perf/x86/intel: ignore CondChgd bit to avoid false NMI handling
  perf symbols: Get kernel start address by symbol name
  perf tools: Fix segfault in cumulative.callchain report
2014-07-16 10:10:27 -10:00
Jiri Olsa
fbe26abe11 perf: Add vm_ops->name call for mmap event name retrieval
The following patch added another way to get mmap name: 78d683e838
("mm, fs: Add vm_ops->name as an alternative to arch_vma_name")

The vdso vma mapping already switch to this and we no longer get vdso
name via arch_vma_name function. Adding this way to the perf mmap
event name retrieval code.

Caught this via perf test:

  $ sudo ./perf test -v 7
   7: Validate PERF_RECORD_* events & perf_sample fields     :
  --- start ---

SNIP

  PERF_RECORD_MMAP for [vdso] missing!
  test child finished with 255
  ---- end ----
  Validate PERF_RECORD_* events & perf_sample fields: FAILED!

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1405353439-14211-1-git-send-email-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-16 13:31:22 +02:00
Peter Zijlstra
4a1c0f262f perf: Fix lockdep warning on process exit
Sasha Levin reported:

> While fuzzing with trinity inside a KVM tools guest running the latest -next
> kernel I've stumbled on the following spew:
>
> ======================================================
> [ INFO: possible circular locking dependency detected ]
> 3.15.0-next-20140613-sasha-00026-g6dd125d-dirty #654 Not tainted
> -------------------------------------------------------
> trinity-c578/9725 is trying to acquire lock:
> (&(&pool->lock)->rlock){-.-...}, at: __queue_work (kernel/workqueue.c:1346)
>
> but task is already holding lock:
> (&ctx->lock){-.....}, at: perf_event_exit_task (kernel/events/core.c:7471 kernel/events/core.c:7533)
>
> which lock already depends on the new lock.

> 1 lock held by trinity-c578/9725:
> #0: (&ctx->lock){-.....}, at: perf_event_exit_task (kernel/events/core.c:7471 kernel/events/core.c:7533)
>
>  Call Trace:
>  dump_stack (lib/dump_stack.c:52)
>  print_circular_bug (kernel/locking/lockdep.c:1216)
>  __lock_acquire (kernel/locking/lockdep.c:1840 kernel/locking/lockdep.c:1945 kernel/locking/lockdep.c:2131 kernel/locking/lockdep.c:3182)
>  lock_acquire (./arch/x86/include/asm/current.h:14 kernel/locking/lockdep.c:3602)
>  _raw_spin_lock (include/linux/spinlock_api_smp.h:143 kernel/locking/spinlock.c:151)
>  __queue_work (kernel/workqueue.c:1346)
>  queue_work_on (kernel/workqueue.c:1424)
>  free_object (lib/debugobjects.c:209)
>  __debug_check_no_obj_freed (lib/debugobjects.c:715)
>  debug_check_no_obj_freed (lib/debugobjects.c:727)
>  kmem_cache_free (mm/slub.c:2683 mm/slub.c:2711)
>  free_task (kernel/fork.c:221)
>  __put_task_struct (kernel/fork.c:250)
>  put_ctx (include/linux/sched.h:1855 kernel/events/core.c:898)
>  perf_event_exit_task (kernel/events/core.c:907 kernel/events/core.c:7478 kernel/events/core.c:7533)
>  do_exit (kernel/exit.c:766)
>  do_group_exit (kernel/exit.c:884)
>  get_signal_to_deliver (kernel/signal.c:2347)
>  do_signal (arch/x86/kernel/signal.c:698)
>  do_notify_resume (arch/x86/kernel/signal.c:751)
>  int_signal (arch/x86/kernel/entry_64.S:600)

Urgh.. so the only way I can make that happen is through:

  perf_event_exit_task_context()
    raw_spin_lock(&child_ctx->lock);
    unclone_ctx(child_ctx)
      put_ctx(ctx->parent_ctx);
    raw_spin_unlock_irqrestore(&child_ctx->lock);

And we can avoid this by doing the change below.

I can't immediately see how this changed recently, but given that you
say it's easy to reproduce, lets fix this.

Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Dave Jones <davej@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140623141242.GB19860@laptop.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-16 13:18:42 +02:00
Peter Zijlstra
1903d50cba perf: Revert ("perf: Always destroy groups on exit")
Vince reported that commit 15a2d4de0e ("perf: Always destroy groups
on exit") causes a regression with grouped events. In particular his
read_group_attached.c test fails.

  https://github.com/deater/perf_event_tests/blob/master/tests/bugs/read_group_attached.c

Because of the context switch optimization in
perf_event_context_sched_out() the 'original' event may end up in the
child process and when that exits the change in the patch in question
destroys the actual grouping.

Therefore revert that change and only destroy inherited groups.

Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/n/tip-zedy3uktcp753q8fw8dagx7a@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-16 13:18:39 +02:00
Jiri Olsa
985c8dcbe1 perf: Make perf_event_init_context() function static
Leftover from '8dc85d5 perf: Multiple task contexts'.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1403598026-2310-1-git-send-email-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-05 11:21:52 +02:00
Linus Torvalds
ef34c6ce49 Oleg Nesterov found and fixed a bug in the perf/ftrace/uprobes code where
running:
 
    # perf probe -x /lib/libc.so.6 syscall
    # echo 1 >> /sys/kernel/debug/tracing/events/probe_libc/enable
    # perf record -e probe_libc:syscall whatever
 
 kills the uprobe. Along the way he found some other minor bugs and clean ups
 that he fixed up making it a total of 4 patches.
 
 Doing unrelated work, I found that the reading of the ftrace trace
 file disables all function tracer callbacks. This was fine when ftrace
 was the only user, but now that it's used by perf and kprobes, this
 is a bug where reading trace can disable kprobes and perf. A very unexpected
 side effect and should be fixed.
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Merge tag 'trace-fixes-v3.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Oleg Nesterov found and fixed a bug in the perf/ftrace/uprobes code
  where running:

    # perf probe -x /lib/libc.so.6 syscall
    # echo 1 >> /sys/kernel/debug/tracing/events/probe_libc/enable
    # perf record -e probe_libc:syscall whatever

  kills the uprobe.  Along the way he found some other minor bugs and
  clean ups that he fixed up making it a total of 4 patches.

  Doing unrelated work, I found that the reading of the ftrace trace
  file disables all function tracer callbacks.  This was fine when
  ftrace was the only user, but now that it's used by perf and kprobes,
  this is a bug where reading trace can disable kprobes and perf.  A
  very unexpected side effect and should be fixed"

* tag 'trace-fixes-v3.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Remove ftrace_stop/start() from reading the trace file
  tracing/uprobes: Fix the usage of uprobe_buffer_enable() in probe_event_enable()
  tracing/uprobes: Kill the bogus UPROBE_HANDLER_REMOVE code in uprobe_dispatcher()
  uprobes: Change unregister/apply to WARN() if uprobe/consumer is gone
  tracing/uprobes: Revert "Support mix of ftrace and perf"
2014-07-03 18:37:25 -07:00
Jiri Olsa
1f9a7268c6 perf: Do not allow optimized switch for non-cloned events
The context check in perf_event_context_sched_out allows
non-cloned context to be part of the optimized schedule
out switch.

This could move non-cloned context into another workload
child. Once this child exits, the context is closed and
leaves all original (parent) events in closed state.

Any other new cloned event will have closed state and not
measure anything. And probably causing other odd bugs.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1403598026-2310-2-git-send-email-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-02 08:35:56 +02:00
Oleg Nesterov
06d0713904 uprobes: Change unregister/apply to WARN() if uprobe/consumer is gone
Add WARN_ON's into uprobe_unregister() and uprobe_apply() to ensure
that nobody tries to play with the dead uprobe/consumer. This helps
to catch the bugs like the one fixed by the previous patch.

In the longer term we should fix this poorly designed interface.
uprobe_register() should return "struct uprobe *" which should be
passed to apply/unregister. Plus other semantic changes, see the
changelog in commit 41ccba029e.

Link: http://lkml.kernel.org/p/20140627170140.GA18322@redhat.com

Acked-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-06-30 13:22:15 -04:00
Ingo Molnar
cf230918cd Merge branch 'perf/core' into perf/urgent, to pick up the latest fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-06-14 14:10:08 +02:00
Linus Torvalds
3737a12761 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull more perf updates from Ingo Molnar:
 "A second round of perf updates:

   - wide reaching kprobes sanitization and robustization, with the hope
     of fixing all 'probe this function crashes the kernel' bugs, by
     Masami Hiramatsu.

   - uprobes updates from Oleg Nesterov: tmpfs support, corner case
     fixes and robustization work.

   - perf tooling updates and fixes from Jiri Olsa, Namhyung Ki, Arnaldo
     et al:
        * Add support to accumulate hist periods (Namhyung Kim)
        * various fixes, refactorings and enhancements"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (101 commits)
  perf: Differentiate exec() and non-exec() comm events
  perf: Fix perf_event_comm() vs. exec() assumption
  uprobes/x86: Rename arch_uprobe->def to ->defparam, minor comment updates
  perf/documentation: Add description for conditional branch filter
  perf/x86: Add conditional branch filtering support
  perf/tool: Add conditional branch filter 'cond' to perf record
  perf: Add new conditional branch filter 'PERF_SAMPLE_BRANCH_COND'
  uprobes: Teach copy_insn() to support tmpfs
  uprobes: Shift ->readpage check from __copy_insn() to uprobe_register()
  perf/x86: Use common PMU interrupt disabled code
  perf/ARM: Use common PMU interrupt disabled code
  perf: Disable sampled events if no PMU interrupt
  perf: Fix use after free in perf_remove_from_context()
  perf tools: Fix 'make help' message error
  perf record: Fix poll return value propagation
  perf tools: Move elide bool into perf_hpp_fmt struct
  perf tools: Remove elide setup for SORT_MODE__MEMORY mode
  perf tools: Fix "==" into "=" in ui_browser__warning assignment
  perf tools: Allow overriding sysfs and proc finding with env var
  perf tools: Consider header files outside perf directory in tags target
  ...
2014-06-12 19:18:49 -07:00
Linus Torvalds
14208b0ec5 Merge branch 'for-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo:
 "A lot of activities on cgroup side.  Heavy restructuring including
  locking simplification took place to improve the code base and enable
  implementation of the unified hierarchy, which currently exists behind
  a __DEVEL__ mount option.  The core support is mostly complete but
  individual controllers need further work.  To explain the design and
  rationales of the the unified hierarchy

        Documentation/cgroups/unified-hierarchy.txt

  is added.

  Another notable change is css (cgroup_subsys_state - what each
  controller uses to identify and interact with a cgroup) iteration
  update.  This is part of continuing updates on css object lifetime and
  visibility.  cgroup started with reference count draining on removal
  way back and is now reaching a point where csses behave and are
  iterated like normal refcnted objects albeit with some complexities to
  allow distinguishing the state where they're being deleted.  The css
  iteration update isn't taken advantage of yet but is planned to be
  used to simplify memcg significantly"

* 'for-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (77 commits)
  cgroup: disallow disabled controllers on the default hierarchy
  cgroup: don't destroy the default root
  cgroup: disallow debug controller on the default hierarchy
  cgroup: clean up MAINTAINERS entries
  cgroup: implement css_tryget()
  device_cgroup: use css_has_online_children() instead of has_children()
  cgroup: convert cgroup_has_live_children() into css_has_online_children()
  cgroup: use CSS_ONLINE instead of CGRP_DEAD
  cgroup: iterate cgroup_subsys_states directly
  cgroup: introduce CSS_RELEASED and reduce css iteration fallback window
  cgroup: move cgroup->serial_nr into cgroup_subsys_state
  cgroup: link all cgroup_subsys_states in their sibling lists
  cgroup: move cgroup->sibling and ->children into cgroup_subsys_state
  cgroup: remove cgroup->parent
  device_cgroup: remove direct access to cgroup->children
  memcg: update memcg_has_children() to use css_next_child()
  memcg: remove tasks/children test from mem_cgroup_force_empty()
  cgroup: remove css_parent()
  cgroup: skip refcnting on normal root csses and cgrp_dfl_root self css
  cgroup: use cgroup->self.refcnt for cgroup refcnting
  ...
2014-06-09 15:03:33 -07:00
Don Zickus
a5a5ba7284 Revert "perf: Disable PERF_RECORD_MMAP2 support"
This reverts commit 3090ffb5a2.

Re-enable the mmap2 interface as we will have a user soon.

Since things have changed since perf disabled mmap2, small tweaks
to the revert had to be done:

o commit 9d4ecc88 forced (n!=8) to become (n<7)
o a new libunwind test needed updating to use mmap2 interface

Signed-off-by: Don Zickus <dzickus@redhat.com>
Link: http://lkml.kernel.org/r/1401461382-209586-1-git-send-email-dzickus@redhat.com
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
2014-06-09 13:34:46 +02:00
Peter Zijlstra
f972eb63b1 perf: Pass protection and flags bits through mmap2 interface
The mmap2 interface was missing the protection and flags bits needed to
accurately determine if a mmap memory area was shared or private and
if it was readable or not.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
[tweaked patch to compile and wrote changelog]
Signed-off-by: Don Zickus <dzickus@redhat.com>
Link: http://lkml.kernel.org/r/1400526833-141779-2-git-send-email-dzickus@redhat.com
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
2014-06-09 12:21:04 +02:00
Adrian Hunter
82b897782d perf: Differentiate exec() and non-exec() comm events
perf tools like 'perf report' can aggregate samples by comm strings,
which generally works.  However, there are other potential use-cases.
For example, to pair up 'calls' with 'returns' accurately (from branch
events like Intel BTS) it is necessary to identify whether the process
has exec'd.  Although a comm event is generated when an 'exec' happens
it is also generated whenever the comm string is changed on a whim
(e.g. by prctl PR_SET_NAME).  This patch adds a flag to the comm event
to differentiate one case from the other.

In order to determine whether the kernel supports the new flag, a
selection bit named 'exec' is added to struct perf_event_attr.  The
bit does nothing but will cause perf_event_open() to fail if the bit
is set on kernels that do not have it defined.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/537D9EBE.7030806@intel.com
Cc: Paul Mackerras <paulus@samba.org>
Cc: Dave Jones <davej@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-06-06 07:56:22 +02:00
Ingo Molnar
ec00010972 Merge branch 'perf/urgent' into perf/core, to resolve conflict and to prepare for new patches
Conflicts:
	arch/x86/kernel/traps.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-06-06 07:55:06 +02:00
Peter Zijlstra
e041e328c4 perf: Fix perf_event_comm() vs. exec() assumption
perf_event_comm() assumes that set_task_comm() is only called on
exec(), and in particular that its only called on current.

Neither are true, as Dave reported a WARN triggered by set_task_comm()
being called on !current.

Separate the exec() hook from the comm hook.

Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/20140521153219.GH5226@laptop.programming.kicks-ass.net
[ Build fix. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-06-06 07:54:02 +02:00
Linus Torvalds
eb3d3ec567 Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm into next
Pull ARM updates from Russell King:

 - Major clean-up of the L2 cache support code.  The existing mess was
   becoming rather unmaintainable through all the additions that others
   have done over time.  This turns it into a much nicer structure, and
   implements a few performance improvements as well.

 - Clean up some of the CP15 control register tweaks for alignment
   support, moving some code and data into alignment.c

 - DMA properties for ARM, from Santosh and reviewed by DT people.  This
   adds DT properties to specify bus translations we can't discover
   automatically, and to indicate whether devices are coherent.

 - Hibernation support for ARM

 - Make ftrace work with read-only text in modules

 - add suspend support for PJ4B CPUs

 - rework interrupt masking for undefined instruction handling, which
   allows us to enable interrupts earlier in the handling of these
   exceptions.

 - support for big endian page tables

 - fix stacktrace support to exclude stacktrace functions from the
   trace, and add save_stack_trace_regs() implementation so that kprobes
   can record stack traces.

 - Add support for the Cortex-A17 CPU.

 - Remove last vestiges of ARM710 support.

 - Removal of ARM "meminfo" structure, finally converting us solely to
   memblock to handle the early memory initialisation.

* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (142 commits)
  ARM: ensure C page table setup code follows assembly code (part II)
  ARM: ensure C page table setup code follows assembly code
  ARM: consolidate last remaining open-coded alignment trap enable
  ARM: remove global cr_no_alignment
  ARM: remove CPU_CP15 conditional from alignment.c
  ARM: remove unused adjust_cr() function
  ARM: move "noalign" command line option to alignment.c
  ARM: provide common method to clear bits in CPU control register
  ARM: 8025/1: Get rid of meminfo
  ARM: 8060/1: mm: allow sub-architectures to override PCI I/O memory type
  ARM: 8066/1: correction for ARM patch 8031/2
  ARM: 8049/1: ftrace/add save_stack_trace_regs() implementation
  ARM: 8065/1: remove last use of CONFIG_CPU_ARM710
  ARM: 8062/1: Modify ldrt fixup handler to re-execute the userspace instruction
  ARM: 8047/1: rwsem: use asm-generic rwsem implementation
  ARM: l2c: trial at enabling some Cortex-A9 optimisations
  ARM: l2c: add warnings for stuff modifying aux_ctrl register values
  ARM: l2c: print a warning with L2C-310 caches if the cache size is modified
  ARM: l2c: remove old .set_debug method
  ARM: l2c: kill L2X0_AUX_CTRL_MASK before anyone else makes use of this
  ...
2014-06-05 15:57:04 -07:00
Oleg Nesterov
40814f6805 uprobes: Teach copy_insn() to support tmpfs
tmpfs is widely used but as Denys reports shmem_aops doesn't have
->readpage() and thus you can't probe a binary on this filesystem.

As Hugh suggested we can use shmem_read_mapping_page() in this case,
just we need to check shmem_mapping() if ->readpage == NULL.

Reported-by: Denys Vlasenko <dvlasenk@redhat.com>
Suggested-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140519184136.GB6750@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-06-05 12:30:11 +02:00
Oleg Nesterov
41ccba029e uprobes: Shift ->readpage check from __copy_insn() to uprobe_register()
copy_insn() fails with -EIO if ->readpage == NULL, but this error
is not propagated unless uprobe_register() path finds ->mm which
already mmaps this file. In this case (say) "perf record" does not
actually install the probe, but the user can't know about this.

Move this check into uprobe_register() so that this problem can be
detected earlier and reported to user.

Note: this is still not perfect,

	- copy_insn() and arch_uprobe_analyze_insn() should be called
	  by uprobe_register() but this is not simple, we need vm_file
	  for read_mapping_page() (although perhaps we can pass NULL),
	  and we need ->mm for is_64bit_mm() (although this logic is
	  broken anyway).

	- uprobe_register() should be called by create_trace_uprobe(),
	  not by probe_event_enable(), so that an error can be detected
	  at "perf probe -x" time. This also needs more changes in the
	  core uprobe code, uprobe register/unregister interface was
	  poorly designed from the very beginning.

Reported-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140519184054.GA6750@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-06-05 12:30:07 +02:00
Vince Weaver
53b25335dd perf: Disable sampled events if no PMU interrupt
Add common code to generate -ENOTSUPP at event creation time if an
architecture attempts to create a sampled event and
PERF_PMU_NO_INTERRUPT is set.

This adds a new pmu->capabilities flag.  Initially we only support
PERF_PMU_NO_INTERRUPT (to indicate a PMU has no support for generating
hardware interrupts) but there are other capabilities that can be
added later.

Signed-off-by: Vince Weaver <vincent.weaver@maine.edu>
Acked-by: Will Deacon <will.deacon@arm.com>
[peterz: rename to PERF_PMU_CAP_* and moved the pmu::capabilities word into a hole]
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1405161708060.11099@vincent-weaver-1.umelst.maine.edu
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-06-05 12:29:55 +02:00
Peter Zijlstra
ebf905fc7a perf: Fix use after free in perf_remove_from_context()
While that mutex should guard the elements, it doesn't guard against the
use-after-free that's from list_for_each_entry_rcu().
__perf_event_exit_task() can actually free the event.

And because list addition/deletion is guarded by both ctx->mutex and
ctx->lock, holding ctx->mutex is sufficient for reading the list, so we
don't actually need the rcu list iteration.

Fixes: 3a497f4863 ("perf: Simplify perf_event_exit_task_context()")
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Dave Jones <davej@redhat.com>
Cc: acme@ghostprotocols.net
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140529170024.GA2315@laptop.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-06-05 12:29:52 +02:00
Ingo Molnar
c56d34064b Merge branch 'perf/uprobes' into perf/core
These bits from Oleg are fully cooked, ship them to Linus.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-06-05 12:26:27 +02:00