Commit graph

4443 commits

Author SHA1 Message Date
David Carrillo-Cisneros 1e0d4f0200 perf inject: Copy events when reordering events in pipe mode
__perf_session__process_pipe_events reuses the same memory buffer to
process all events in the pipe.

When reordering is needed (e.g. -b option), events are not immediately
flushed, but kept around until reordering is possible, causing
memory corruption.

The problem is usually observed by a "Unknown sample error" output. It
can easily be reproduced by:

  perf record -o - noploop | perf inject -b > output

Committer testing:

Before:

  $ perf record -o - stress -t 2 -c 2 | perf inject -b > /dev/null
  stress: info: [8297] dispatching hogs: 2 cpu, 0 io, 0 vm, 0 hdd
  stress: info: [8297] successful run completed in 2s
  [ perf record: Woken up 3 times to write data ]
  [ perf record: Captured and wrote 0.000 MB - ]
  Warning:
  Found 1 unknown events!

  Is this an older tool processing a perf.data file generated by a more recent tool?

  If that is not the case, consider reporting to linux-kernel@vger.kernel.org.

  $

After:

  $ perf record -o - stress -t 2 -c 2 | perf inject -b > /dev/null
  stress: info: [9027] dispatching hogs: 2 cpu, 0 io, 0 vm, 0 hdd
  stress: info: [9027] successful run completed in 2s
  [ perf record: Woken up 3 times to write data ]
  [ perf record: Captured and wrote 0.000 MB - ]
  no symbols found in /usr/bin/stress, maybe install a debug package?
  no symbols found in /usr/bin/stress, maybe install a debug package?
  $

Signed-off-by: David Carrillo-Cisneros <davidcc@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Simon Que <sque@chromium.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20170410201432.24807-3-davidcc@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-11 15:23:41 -03:00
Christian Borntraeger d9f8dfa9ba perf annotate s390: Implement jump types for perf annotate
Implement simple detection for all kind of jumps and branches.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Andreas Krebbel <krebbel@linux.vnet.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-s390 <linux-s390@vger.kernel.org>
Cc: stable@kernel.org # v4.10+
Link: http://lkml.kernel.org/r/1491465112-45819-3-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-11 15:23:40 -03:00
Christian Borntraeger e77852b32d perf annotate s390: Fix perf annotate error -95 (4.10 regression)
since 4.10 perf annotate exits on s390 with an "unknown error -95".
Turns out that commit 786c1b5184 ("perf annotate: Start supporting
cross arch annotation") added a hard requirement for architecture
support when objdump is used but only provided x86 and arm support.
Meanwhile power was added so lets add s390 as well.

While at it make sure to implement the branch and jump types.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Andreas Krebbel <krebbel@linux.vnet.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-s390 <linux-s390@vger.kernel.org>
Cc: stable@kernel.org # v4.10+
Fixes: 786c1b5184 "perf annotate: Start supporting cross arch annotation"
Link: http://lkml.kernel.org/r/1491465112-45819-2-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-11 15:23:39 -03:00
Arnaldo Carvalho de Melo ecbe5e10d4 perf string: Simplify ltrim() implementation
We don't need to use strlen(), a var, or check for the end explicitely,
isspace('\0') is false:

  [acme@jouet c]$ cat ltrim.c
  #include <ctype.h>
  #include <stdio.h>

  static char *ltrim(char *s)
  {
	  while (isspace(*s))
		  ++s;
	  return s;
  }

  int main(void)
  {
	  printf("ltrim(\"\")='%s'\n", ltrim(""));
	  return 0;
  }
  [acme@jouet c]$ ./ltrim
  ltrim("")=''
  [acme@jouet c]$

Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Taeung Song <treeze.taeung@gmail.com>
Link: http://lkml.kernel.org/n/tip-w3nk0x3pai2vojk2ab6kdvaw@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-11 15:23:39 -03:00
Taeung Song bdd97ca63f perf tools: Refactor the code to strip command name with {l,r}trim()
After reading command name from /proc/<pid>/status, use ltrim() and
rtrim() to strip command name, not using just while loop, isspace() and
etc.

Signed-off-by: Taeung Song <treeze.taeung@gmail.com>
Acked-by: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1491575061-704-6-git-send-email-treeze.taeung@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-11 15:23:26 -03:00
Taeung Song aa4beb10a9 perf pmu: Refactor wordwrap() with ltrim()
Signed-off-by: Taeung Song <treeze.taeung@gmail.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1491575061-704-5-git-send-email-treeze.taeung@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-11 08:45:10 -03:00
Jin Yao 32ccb130f5 perf evsel: Return exact sub event which failed with EPERM for wildcards
The kernel has a special check for a specific irq_vectors trace event.

TRACE_EVENT_PERF_PERM(irq_work_exit,
	is_sampling_event(p_event) ? -EPERM : 0);

The perf-record fails for this irq_vectors event when it is present,
like when using a wildcard:

  root@skl:/tmp# perf record -a -e irq_vectors:* sleep 2
  Error:
  You may not have permission to collect system-wide stats.

  Consider tweaking /proc/sys/kernel/perf_event_paranoid,
  which controls use of the performance events system by
  unprivileged users (without CAP_SYS_ADMIN).

  The current value is 2:

    -1: Allow use of (almost) all events by all users
  >= 0: Disallow raw tracepoint access by users without CAP_IOC_LOCK
  >= 1: Disallow CPU event access by users without CAP_SYS_ADMIN
  >= 2: Disallow kernel profiling by users without CAP_SYS_ADMIN

  To make this setting permanent, edit /etc/sysctl.conf too, e.g.:

        kernel.perf_event_paranoid = -1

This patch prints out the exact sub event that failed with EPERM for
wildcards to help in understanding what went wrong when this event is
present:

After the patch:

  root@skl:/tmp# perf record -a -e irq_vectors:* sleep 2
  Error:
  No permission to enable irq_vectors:irq_work_exit event.

  You may not have permission to collect system-wide stats.
  ......

Committer notes:

So we have a lot of irq_vectors events:

  [root@jouet ~]# perf list irq_vectors:*

  List of pre-defined events (to be used in -e):

    irq_vectors:call_function_entry                    [Tracepoint event]
    irq_vectors:call_function_exit                     [Tracepoint event]
    irq_vectors:call_function_single_entry             [Tracepoint event]
    irq_vectors:call_function_single_exit              [Tracepoint event]
    irq_vectors:deferred_error_apic_entry              [Tracepoint event]
    irq_vectors:deferred_error_apic_exit               [Tracepoint event]
    irq_vectors:error_apic_entry                       [Tracepoint event]
    irq_vectors:error_apic_exit                        [Tracepoint event]
    irq_vectors:irq_work_entry                         [Tracepoint event]
    irq_vectors:irq_work_exit                          [Tracepoint event]
    irq_vectors:local_timer_entry                      [Tracepoint event]
    irq_vectors:local_timer_exit                       [Tracepoint event]
    irq_vectors:reschedule_entry                       [Tracepoint event]
    irq_vectors:reschedule_exit                        [Tracepoint event]
    irq_vectors:spurious_apic_entry                    [Tracepoint event]
    irq_vectors:spurious_apic_exit                     [Tracepoint event]
    irq_vectors:thermal_apic_entry                     [Tracepoint event]
    irq_vectors:thermal_apic_exit                      [Tracepoint event]
    irq_vectors:threshold_apic_entry                   [Tracepoint event]
    irq_vectors:threshold_apic_exit                    [Tracepoint event]
    irq_vectors:x86_platform_ipi_entry                 [Tracepoint event]
    irq_vectors:x86_platform_ipi_exit                  [Tracepoint event]
  #

And some may be sampled:

  [root@jouet ~]# perf record -e irq_vectors:local* sleep 20s
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.020 MB perf.data (2 samples) ]
  [root@jouet ~]# perf report -D | egrep 'stats:|events:'
  Aggregated stats:
             TOTAL events:        155
              MMAP events:        144
              COMM events:          2
              EXIT events:          1
            SAMPLE events:          2
             MMAP2 events:          4
    FINISHED_ROUND events:          1
         TIME_CONV events:          1
  irq_vectors:local_timer_entry stats:
             TOTAL events:          1
            SAMPLE events:          1
  irq_vectors:local_timer_exit stats:
             TOTAL events:          1
            SAMPLE events:          1
  [root@jouet ~]#

But, as shown in the tracepoint definition at the start of this message,
some, like "irq_vectors:irq_work_exit", may not be sampled, just counted,
i.e. if we try to sample, as when using 'perf record', we get an error:

  [root@jouet ~]# perf record -e irq_vectors:irq_work_exit
  Error:
  You may not have permission to collect system-wide stats.

  Consider tweaking /proc/sys/kernel/perf_event_paranoid,
<SNIP>

The error message is misleading, this patch will help in pointing out
what is the event causing such an error, but the error message needs
improvement, i.e. we need to figure out a way to check if a tracepoint
is counting only, like this one, when all we can do is to count it with
'perf stat', at most printing the delta using interval printing, as in:

   [root@jouet ~]# perf stat -I 5000 -e irq_vectors:irq_work_*
  #           time             counts unit events
       5.000168871                  0      irq_vectors:irq_work_entry
       5.000168871                  0      irq_vectors:irq_work_exit
      10.000676730                  0      irq_vectors:irq_work_entry
      10.000676730                  0      irq_vectors:irq_work_exit
      15.001122415                  0      irq_vectors:irq_work_entry
      15.001122415                  0      irq_vectors:irq_work_exit
      20.001298051                  0      irq_vectors:irq_work_entry
      20.001298051                  0      irq_vectors:irq_work_exit
      25.001485020                  1      irq_vectors:irq_work_entry
      25.001485020                  1      irq_vectors:irq_work_exit
      30.001658706                  0      irq_vectors:irq_work_entry
      30.001658706                  0      irq_vectors:irq_work_exit
  ^C    32.045711878                  0      irq_vectors:irq_work_entry
      32.045711878                  0      irq_vectors:irq_work_exit

  [root@jouet ~]#

But at least, when we use a wildcard, this patch helps a bit.

Signed-off-by: Yao Jin <yao.jin@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1491566932-503-1-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-11 08:45:10 -03:00
Arnaldo Carvalho de Melo dadafc315d perf callchains: Switch from strtok() to strtok_r() when parsing options
Trying to keep everything reentrant.

Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/n/tip-rdce0p2k9e1b4qnrb8ki9mtf@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-11 08:45:09 -03:00
Taeung Song 99094a5e94 perf annotate: Fix missing number of samples for source_line_samples
The option 'show-total-period' works fine without a option '-l'.  But if
running 'perf annotate --stdio -l --show-total-period', you can see a
problem showing only zero '0' for number of samples.

Before:
    $ perf annotate --stdio -l --show-total-period
...
       0 :        400816:       push   %rbp
       0 :        400817:       mov    %rsp,%rbp
       0 :        40081a:       mov    %edi,-0x24(%rbp)
       0 :        40081d:       mov    %rsi,-0x30(%rbp)
       0 :        400821:       mov    -0x24(%rbp),%eax
       0 :        400824:       mov    -0x30(%rbp),%rdx
       0 :        400828:       mov    (%rdx),%esi
       0 :        40082a:       mov    $0x0,%edx
...

The reason is it was missed to set number of samples of
source_line_samples, so set it ordinarily.

After:
    $ perf annotate --stdio -l --show-total-period
...
       3 :        400816:       push   %rbp
       4 :        400817:       mov    %rsp,%rbp
       0 :        40081a:       mov    %edi,-0x24(%rbp)
       0 :        40081d:       mov    %rsi,-0x30(%rbp)
       1 :        400821:       mov    -0x24(%rbp),%eax
       2 :        400824:       mov    -0x30(%rbp),%rdx
       0 :        400828:       mov    (%rdx),%esi
       1 :        40082a:       mov    $0x0,%edx
...

Signed-off-by: Taeung Song <treeze.taeung@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Martin Liska <mliska@suse.cz>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: 0c4a5bcea4 ("perf annotate: Display total number of samples with --show-total-period")
Link: http://lkml.kernel.org/r/1490703125-13643-1-git-send-email-treeze.taeung@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-04 21:08:00 -03:00
Arnaldo Carvalho de Melo 9c0899f157 perf tools: Don't die on a print function
Trying to remove die() calls from library functions, postponing exiting
to the tool main code.

Link: http://lkml.kernel.org/n/tip-ackxq5nqe39gunln3tkczs42@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-04 12:11:07 -03:00
Arnaldo Carvalho de Melo f05082b547 perf tools: Handle allocation failures gracefully
The callers of perf_read_values__enlarge_counters() already propagate
errors, so just print some debug diagnostics and handle allocation
failures gracefully, not trying to do silly things like 'a =
realloc(a)'.

Link: http://lkml.kernel.org/n/tip-nsmmh7uzpg35rzcl9nq7yztp@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-04-04 12:05:37 -03:00
Jiri Olsa 3e00cbe889 perf tools: Do not fail in case of empty HOME env variable
Currently we fail in the following case:

  $ unset HOME
  $ ./perf record ls
  $ echo $?
  255

It's because the config code init fails due to a missing HOME variable
value. Fix this by skipping the user config init if there's no HOME
variable value.

Reported-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20170330144637.7468-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-31 11:26:04 -03:00
Colin Ian King a596a877fd perf utils: Fix spelling mistake: "Invalud" -> "Invalid"
Trivial fix to spelling mistake in pr_debug message.

Signed-off-by: Colin King <colin.king@canonical.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Krister Johansen <kjlx@templeofstupid.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: kernel-janitors@vger.kernel.org
Link: http://lkml.kernel.org/r/20170330095440.19444-1-colin.king@canonical.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-30 11:09:42 -03:00
Jin Yao c1dfcfad58 perf report: Drop cycles 0 for LBR print
For some platforms, for example Broadwell, it doesn't support cycles
for LBR. But the perf always prints cycles:0, it's not necessary.

The patch refactors the LBR info print code and drops the cycles:0.

For example: perf report --branch-history --no-children --stdio

On Broadwell:
--0.91%--__random_r random_r.c:394 (iterations:2)
          __random_r random_r.c:360 (predicted:0.0%)
          __random_r random_r.c:380 (predicted:0.0%)
          __random_r random_r.c:357

On Skylake:
--1.07%--main div.c:39 (predicted:52.4% cycles:1 iterations:17)
          main div.c:44 (predicted:52.4% cycles:1)
          main div.c:42 (cycles:2)
          compute_flag div.c:28 (cycles:2)
          compute_flag div.c:27 (cycles:1)
          rand rand.c:28 (cycles:1)
          rand rand.c:28 (cycles:1)
          __random random.c:298 (cycles:1)
          __random random.c:297 (cycles:1)
          __random random.c:295 (cycles:1)
          __random random.c:295 (cycles:1)
          __random random.c:295 (cycles:1)

Signed-off-by: Yao Jin <yao.jin@linux.intel.com>
	Reviewed-by: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Link: http://lkml.kernel.org/r/1489046786-10061-1-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-28 16:20:59 -03:00
Ravi Bangoria d451a205da perf/sdt/x86: Move OP parser to tools/perf/arch/x86/
SDT marker argument is in N@OP format. N is the size of argument and OP
is the actual assembly operand. OP is arch dependent component and hence
it's parsing logic also should be placed under tools/perf/arch/.

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexis Berlemont <alexis.berlemont@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170328094754.3156-3-ravi.bangoria@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-28 12:25:30 -03:00
Arnaldo Carvalho de Melo c68677014b perf tools: Remove support for command aliases
This came from 'git', but isn't documented anywhere in
tools/perf/Documentation/, looks like baggage we can do without, ditch
it.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-e7uwkn60t4hmlnwj99ba4t2s@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-28 11:19:59 -03:00
Ingo Molnar 3906a13a6b perf/core improvements and fixes:
New features:
 
 - Handle inline functions in callchains (Jin Yao)
 
 - Enable sorting by srcline as key (Milian Wolff)
 
 Fixes:
 
 - Fix no_size logic in addr_filter__resolve_kernel_syms() in the
   auxtrace code (Adrian Hunter)
 
 - Fix some thread refcount leaks in 'perf trace' (Arnaldo Carvalho de Melo)
 
 - Fix divide by zero when calculating percent for an event in a group in
   the annotate by source line code (Taeung Song)
 
 - build-id files now aren't anymore symlinks, their parent directories
   are, so readlink the later (Taeung Song)
 
 - Assorted fixes for null termination problems, mostly related to
   readlink, detected by valgrind (Tommi Rantala)
 
 Infrastructure:
 
 - Make vfs_getname probe point logic in 'perf trace' more robust
   wrt length of pathname (Arnaldo Carvalho de Melo)
 
 - Remove unused 'prefix' parameter from builtins main functions (Arnaldo Carvalho de Melo)
 
 - Show 'perf list sdt' option in man page (Ravi Bangoria)
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-core-for-mingo-4.12-20170327' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:

New features:

 - Handle inline functions in callchains (Jin Yao)

 - Enable sorting by srcline as key (Milian Wolff)

Fixes:

 - Fix no_size logic in addr_filter__resolve_kernel_syms() in the
   auxtrace code (Adrian Hunter)

 - Fix some thread refcount leaks in 'perf trace' (Arnaldo Carvalho de Melo)

 - Fix divide by zero when calculating percent for an event in a group in
   the annotate by source line code (Taeung Song)

 - build-id files now aren't anymore symlinks, their parent directories
   are, so readlink the later (Taeung Song)

 - Assorted fixes for null termination problems, mostly related to
   readlink, detected by valgrind (Tommi Rantala)

Infrastructure changes:

 - Make vfs_getname probe point logic in 'perf trace' more robust
   wrt length of pathname (Arnaldo Carvalho de Melo)

 - Remove unused 'prefix' parameter from builtins main functions (Arnaldo Carvalho de Melo)

 - Show 'perf list sdt' option in man page (Ravi Bangoria)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-28 07:44:43 +02:00
Ingo Molnar d652f4bbca Merge branch 'perf/urgent' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-28 07:44:25 +02:00
Tommi Rantala 55f77128e7 perf utils: Readlink /proc/self/exe to find the perf binary
Simplification: it is easier to open /proc/self/exe than /proc/$pid/exe.

Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170322130624.21881-7-tommi.t.rantala@nokia.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-27 15:37:54 -03:00
Tommi Rantala d4b364df5f perf utils: Null terminate buf in read_ftrace_printk()
Ensure that the string that we read from the data file is null terminated.

Valgrind was complaining:

  ==31357== Invalid read of size 1
  ==31357==    at 0x4EC8C1: __strtok_r_1c (string2.h:200)
  ==31357==    by 0x4EC8C1: parse_ftrace_printk (trace-event-parse.c:161)
  ==31357==    by 0x4F82A8: read_ftrace_printk (trace-event-read.c:204)
  ==31357==    by 0x4F82A8: trace_report (trace-event-read.c:468)
  ==31357==    by 0x4CD552: process_tracing_data (header.c:1576)
  ==31357==    by 0x4D3397: perf_file_section__process (header.c:2705)
  ==31357==    by 0x4D3397: perf_header__process_sections (header.c:2488)
  ==31357==    by 0x4D3397: perf_session__read_header (header.c:2925)
  ==31357==    by 0x4E71E2: perf_session__open (session.c:32)
  ==31357==    by 0x4E71E2: perf_session__new (session.c:139)
  ==31357==    by 0x429F5D: cmd_annotate (builtin-annotate.c:472)
  ==31357==    by 0x497150: run_builtin (perf.c:359)
  ==31357==    by 0x428CE0: handle_internal_command (perf.c:421)
  ==31357==    by 0x428CE0: run_argv (perf.c:467)
  ==31357==    by 0x428CE0: main (perf.c:614)
  ==31357==  Address 0x8ac0efb is 0 bytes after a block of size 1,963 alloc'd
  ==31357==    at 0x4C2DB9D: malloc (vg_replace_malloc.c:299)
  ==31357==    by 0x4F827B: read_ftrace_printk (trace-event-read.c:195)
  ==31357==    by 0x4F827B: trace_report (trace-event-read.c:468)
  ==31357==    by 0x4CD552: process_tracing_data (header.c:1576)
  ==31357==    by 0x4D3397: perf_file_section__process (header.c:2705)
  ==31357==    by 0x4D3397: perf_header__process_sections (header.c:2488)
  ==31357==    by 0x4D3397: perf_session__read_header (header.c:2925)
  ==31357==    by 0x4E71E2: perf_session__open (session.c:32)
  ==31357==    by 0x4E71E2: perf_session__new (session.c:139)
  ==31357==    by 0x429F5D: cmd_annotate (builtin-annotate.c:472)
  ==31357==    by 0x497150: run_builtin (perf.c:359)
  ==31357==    by 0x428CE0: handle_internal_command (perf.c:421)
  ==31357==    by 0x428CE0: run_argv (perf.c:467)
  ==31357==    by 0x428CE0: main (perf.c:614)

Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170322130624.21881-6-tommi.t.rantala@nokia.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-27 15:37:35 -03:00
Tommi Rantala b7126ef786 perf utils: use sizeof(buf) - 1 in readlink() call
Ensure that we have space for the null byte in buf.

Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170322130624.21881-5-tommi.t.rantala@nokia.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-27 15:36:27 -03:00
Tommi Rantala 5a2342111c perf buildid: Do not assume that readlink() returns a null terminated string
Valgrind was complaining:

  $ valgrind ./perf list >/dev/null
  ==11643== Memcheck, a memory error detector
  ==11643== Copyright (C) 2002-2015, and GNU GPL'd, by Julian Seward et al.
  ==11643== Using Valgrind-3.12.0 and LibVEX; rerun with -h for copyright info
  ==11643== Command: ./perf list
  ==11643==
  ==11643== Conditional jump or move depends on uninitialised value(s)
  ==11643==    at 0x4C30620: rindex (vg_replace_strmem.c:199)
  ==11643==    by 0x49DAA9: build_id_cache__origname (build-id.c:198)
  ==11643==    by 0x49E1C7: build_id_cache__valid_id (build-id.c:222)
  ==11643==    by 0x49E1C7: build_id_cache__list_all (build-id.c:507)
  ==11643==    by 0x4B9C8F: print_sdt_events (parse-events.c:2067)
  ==11643==    by 0x4BB0B3: print_events (parse-events.c:2313)
  ==11643==    by 0x439501: cmd_list (builtin-list.c:53)
  ==11643==    by 0x497150: run_builtin (perf.c:359)
  ==11643==    by 0x428CE0: handle_internal_command (perf.c:421)
  ==11643==    by 0x428CE0: run_argv (perf.c:467)
  ==11643==    by 0x428CE0: main (perf.c:614)
  [...]

Additionally, a zero length result from readlink() is not very interesting.

Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170322130624.21881-3-tommi.t.rantala@nokia.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-27 15:35:06 -03:00
Tommi Rantala 2ccc220238 perf buildid: Do not update SDT cache with null filename
Valgrind was complaining:

  ==2633== Syscall param open(filename) points to unaddressable byte(s)
  ==2633==    at 0x5281CC0: __open_nocancel (syscall-template.S:84)
  ==2633==    by 0x537D38: open (fcntl2.h:53)
  ==2633==    by 0x537D38: get_sdt_note_list (symbol-elf.c:2017)
  ==2633==    by 0x5396FD: probe_cache__scan_sdt (probe-file.c:700)
  ==2633==    by 0x49EA2C: build_id_cache__add_sdt_cache (build-id.c:625)
  ==2633==    by 0x49EA2C: build_id_cache__add_s (build-id.c:697)
  ==2633==    by 0x49EE72: build_id_cache__add_b (build-id.c:717)
  ==2633==    by 0x49EE72: dso__cache_build_id (build-id.c:782)
  ==2633==    by 0x49F190: __dsos__cache_build_ids (build-id.c:793)
  ==2633==    by 0x49F190: machine__cache_build_ids (build-id.c:801)
  ==2633==    by 0x49F190: perf_session__cache_build_ids (build-id.c:815)
  ==2633==    by 0x4CD4F2: write_build_id (header.c:165)
  ==2633==    by 0x4D26F7: do_write_feat (header.c:2296)
  ==2633==    by 0x4D26F7: perf_header__adds_write (header.c:2335)
  ==2633==    by 0x4D26F7: perf_session__write_header (header.c:2414)
  ==2633==    by 0x43B324: __cmd_record (builtin-record.c:1154)
  ==2633==    by 0x43B324: cmd_record (builtin-record.c:1839)
  ==2633==    by 0x455A07: __cmd_record (builtin-kmem.c:1868)
  ==2633==    by 0x455A07: cmd_kmem (builtin-kmem.c:1944)
  ==2633==    by 0x497150: run_builtin (perf.c:359)
  ==2633==    by 0x428CE0: handle_internal_command (perf.c:421)
  ==2633==    by 0x428CE0: run_argv (perf.c:467)
  ==2633==    by 0x428CE0: main (perf.c:614)
  ==2633==  Address 0x0 is not stack'd, malloc'd or (recently) free'd

Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tommi Rantala <tommi.t.rantala@nokia.com>
Link: http://lkml.kernel.org/r/20170322130624.21881-2-tommi.t.rantala@nokia.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-27 15:33:36 -03:00
Taeung Song 2e933b1274 perf annotate: Fix a bug of division by zero when calculating percent
Currently perf-annotate with --print-line can print
-nan(0x8000000000000) because of division by zero when calculating
percent. The division by zero happens when a sum of samples is zero in
symbol__get_source_line(), so fix it.

For example:

After running 'perf record' like below,

    $ perf record -e "{cycles,page-faults,branch-misses}" ./a.out

Before:

    $ perf annotate --stdio -l

  Sorted summary for file /home/taeung/workspace/a.out
  ----------------------------------------------

   32.89    -nan    7.04 a.c:38
   25.14    -nan    0.00 a.c:34
   16.26    -nan   56.34 a.c:31
   15.88    -nan    1.41 a.c:37
    5.67    -nan    0.00 a.c:39
    1.13    -nan   35.21 a.c:26
    0.95    -nan    0.00 a.c:44
    0.57    -nan    0.00 a.c:32
   Percent                 |      Source code & Disassembly of a.out for cycles (529 samples)
  -----------------------------------------------------------------------------------------
                         :
  ...

   a.c:26    0.57    -nan    4.23 :         40081a:       mov    %edi,-0x24(%rbp)
   a.c:26    0.00    -nan    9.86 :         40081d:       mov    %rsi,-0x30(%rbp)

  ...

However, if a sum of samples is zero (e.g. 'page-faults'),
skip calculating percent.

After:

    $ perf annotate --stdio -l

  Sorted summary for file /home/taeung/workspace/a.out
  ----------------------------------------------

   32.89    0.00    7.04 a.c:38
   25.14    0.00    0.00 a.c:34
   16.26    0.00   56.34 a.c:31
   15.88    0.00    1.41 a.c:37
    5.67    0.00    0.00 a.c:39
    1.13    0.00   35.21 a.c:26
    0.95    0.00    0.00 a.c:44
    0.57    0.00    0.00 a.c:32
   Percent                 |      Source code & Disassembly of old for cycles (529 samples)
  -----------------------------------------------------------------------------------------
                         :
  ...

  a.c:26    0.57    0.00    4.23 :         40081a:       mov    %edi,-0x24(%rbp)
  a.c:26    0.00    0.00    9.86 :         40081d:       mov    %rsi,-0x30(%rbp)

  ...

Signed-off-by: Taeung Song <treeze.taeung@gmail.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1490598638-13947-3-git-send-email-treeze.taeung@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-27 15:04:56 -03:00
Taeung Song 6ebd2547dd perf annotate: Fix a bug following symbolic link of a build-id file
It is wrong way to read link name from a build-id file.  Because a
build-id file is not anymore a symbolic link but build-id directory of
it is symbolic link, so fix it.

For example, if build-id file name gotten from
dso__build_id_filename() is as below,

  /root/.debug/.build-id/4f/75c7d197c951659d1c1b8b5fd49bcdf8f3f8b1/elf

To correctly read link name of build-id, use the build-id dir path that
is a symbolic link, instead of the above build-id file name like below.

  /root/.debug/.build-id/4f/75c7d197c951659d1c1b8b5fd49bcdf8f3f8b1

Signed-off-by: Taeung Song <treeze.taeung@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1490598638-13947-2-git-send-email-treeze.taeung@gmail.com
Fixes: 01412261d9 ("perf buildid-cache: Use path/to/bin/buildid/elf instead of path/to/bin/buildid")
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-27 14:58:20 -03:00
Milian Wolff 5dfa210e40 perf report: Enable sorting by srcline as key
Often it is interesting to know how costly a given source line is in
total. Previously, one had to build these sums manually based on all
addresses that pointed to the same source line. This patch introduces
srcline as a sort key, which will do the aggregation for us.

Paired with the recent addition of showing inline frames, this makes
perf report much more useful for many C++ work loads.

The following shows the new feature in action. First, let's show the
status quo output when we sort by address. The result contains many hist
entries that generate the same output:

  ~~~~~~~~~~~~~~~~
  $ perf report --stdio --inline -g address
  # Children      Self  Command       Shared Object        Symbol
  # ........  ........  ............  ...................  .........................................
  #
      99.89%    35.34%  cpp-inlining  cpp-inlining         [.] main
            |
            |--64.55%--main complex:655
            |          /home/milian/projects/kdab/rnd/hotspot/tests/test-clients/cpp-inlining/main.cpp:39 (inline)
            |          /usr/include/c++/6.3.1/complex:664 (inline)
            |          |
            |          |--60.31%--hypot +20
            |          |          |
            |          |          |--8.52%--__hypot_finite +273
            |          |          |
            |          |          |--7.32%--__hypot_finite +411
...
             --35.34%--_start +4194346
                       __libc_start_main +241
                       |
                       |--6.65%--main random.tcc:3326
                       |          /home/milian/projects/kdab/rnd/hotspot/tests/test-clients/cpp-inlining/main.cpp:39 (inline)
                       |          /usr/include/c++/6.3.1/bits/random.h:1809 (inline)
                       |          /usr/include/c++/6.3.1/bits/random.h:1818 (inline)
                       |          /usr/include/c++/6.3.1/bits/random.h:185 (inline)
                       |
                       |--2.70%--main random.tcc:3326
                       |          /home/milian/projects/kdab/rnd/hotspot/tests/test-clients/cpp-inlining/main.cpp:39 (inline)
                       |          /usr/include/c++/6.3.1/bits/random.h:1809 (inline)
                       |          /usr/include/c++/6.3.1/bits/random.h:1818 (inline)
                       |          /usr/include/c++/6.3.1/bits/random.h:185 (inline)
                       |
                       |--1.69%--main random.tcc:3326
                       |          /home/milian/projects/kdab/rnd/hotspot/tests/test-clients/cpp-inlining/main.cpp:39 (inline)
                       |          /usr/include/c++/6.3.1/bits/random.h:1809 (inline)
                       |          /usr/include/c++/6.3.1/bits/random.h:1818 (inline)
                       |          /usr/include/c++/6.3.1/bits/random.h:185 (inline)
  ...
  ~~~~~~~~~~~~~~~~

With this patch and `-g srcline` we instead get the following output:

  ~~~~~~~~~~~~~~~~
  $ perf report --stdio --inline -g srcline
  # Children      Self  Command       Shared Object        Symbol
  # ........  ........  ............  ...................  .........................................
  #
      99.89%    35.34%  cpp-inlining  cpp-inlining         [.] main
            |
            |--64.55%--main complex:655
            |          /home/milian/projects/kdab/rnd/hotspot/tests/test-clients/cpp-inlining/main.cpp:39 (inline)
            |          /usr/include/c++/6.3.1/complex:664 (inline)
            |          |
            |          |--64.02%--hypot
            |          |          |
            |          |           --59.81%--__hypot_finite
            |          |
            |           --0.53%--cabs
            |
             --35.34%--_start
                       __libc_start_main
                       |
                       |--12.48%--main random.tcc:3326
                       |          /home/milian/projects/kdab/rnd/hotspot/tests/test-clients/cpp-inlining/main.cpp:39 (inline)
                       |          /usr/include/c++/6.3.1/bits/random.h:1809 (inline)
                       |          /usr/include/c++/6.3.1/bits/random.h:1818 (inline)
                       |          /usr/include/c++/6.3.1/bits/random.h:185 (inline)
  ...
  ~~~~~~~~~~~~~~~~

Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Yao Jin <yao.jin@linux.intel.com>
Link: http://lkml.kernel.org/r/20170318214928.9047-1-milian.wolff@kdab.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-27 12:13:28 -03:00
Jin Yao 0d3eb0b778 perf report: Show inline stack for browser mode
If the address belongs to an inlined function, the source information
back to the first non-inlined function will be printed.

For example:

1. Show inlined function name
   perf report -g function --inline

-    0.69%     0.00%  inline   ld-2.23.so           [.] dl_main
   - dl_main
        0.56% _dl_relocate_object
         _dl_relocate_object (inline)
         elf_dynamic_do_Rela (inline)

2. Show the file/line information
   perf report -g address --inline

-    0.69%     0.00%  inline   ld-2.23.so           [.] _dl_start
     _dl_start rtld.c:307
      /build/glibc-GKVZIf/glibc-2.23/elf/rtld.c:413 (inline)
   + _dl_sysdep_start dl-sysdep.c:250

Signed-off-by: Yao Jin <yao.jin@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Milian Wolff <milian.wolff@kdab.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Link: http://lkml.kernel.org/r/1490474069-15823-6-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-27 12:12:59 -03:00
Jin Yao f3a60646cc perf report: Introduce --inline option
It takes some time to look for inline stack for callgraph addresses.  So
it provides new option "--inline" to let user decide if enable this
feature.

  --inline:

  If a callgraph address belongs to an inlined function, the inline stack
  will be printed. Each entry is the inline function name or file/line.

Signed-off-by: Yao Jin <yao.jin@linux.intel.com>
Tested-by: Milian Wolff <milian.wolff@kdab.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Link: http://lkml.kernel.org/r/1490474069-15823-4-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-27 12:01:46 -03:00
Jin Yao a64489c56c perf report: Find the inline stack for a given address
It would be useful for perf to support a mode to query the inline stack
for a given callgraph address. This would simplify finding the right
code in code that does a lot of inlining.

The srcline.c has contained the code which supports to translate the
address to filename:line_nr. This patch just extends the function to let
it support getting the inline stacks.

It introduces the inline_list which will store the inline function
result (filename:line_nr and funcname).

If BFD lib is not supported, the result is only filename:line_nr.

Signed-off-by: Yao Jin <yao.jin@linux.intel.com>
Tested-by: Milian Wolff <milian.wolff@kdab.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Link: http://lkml.kernel.org/r/1490474069-15823-3-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-27 12:00:38 -03:00
Jin Yao 5580338d0f perf report: Refactor common code in srcline.c
Introduce dso__name() and filename_split() out of existing code because
these codes will be used in several places in next patch.

For filename_split(), it may also solve a potential memory leak in
existing code. In existing addr2line(),

        sep = strchr(filename, ':');
        if (sep) {
                *sep++ = '\0';
                *file = filename;
                *line_nr = strtoul(sep, NULL, 0);
                ret = 1;
        }

out:
        pclose(fp);
        return ret;

If sep is NULL, filename is not freed or returned via file.

Signed-off-by: Yao Jin <yao.jin@linux.intel.com>
Tested-by: Milian Wolff <milian.wolff@kdab.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Link: http://lkml.kernel.org/r/1490474069-15823-2-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-27 11:59:23 -03:00
Adrian Hunter c3a0bbc7ad perf auxtrace: Fix no_size logic in addr_filter__resolve_kernel_syms()
Address filtering with kernel symbols incorrectly resulted in the error
"Cannot determine size of symbol" because the no_size logic was the wrong
way around.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Andi Kleen <ak@linux.intel.com>
Cc: stable@vger.kernel.org # v4.9+
Link: http://lkml.kernel.org/r/1490357752-27942-1-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-27 11:58:08 -03:00
Andi Kleen bf874fcf9f perf list: Move extra details printing to new option
Move the printing of perf expressions and internal events to a new
clearer --details flag, instead of lumping it together with other debug
options in --debug. This makes it clearer to use.

Before

  perf list --debug
  ...
  unc_m_power_critical_throttle_cycles
         [Cycles all ranks are in critical thermal throttle. Unit: uncore_imc]
          uncore_imc_2/event=0x86/  MetricName: power_critical_throttle_cycles % MetricExpr: (unc_m_power_critical_throttle_cycles / unc_m_clockticks) * 100.

after

  perf list --details
  ...
  unc_m_power_critical_throttle_cycles
         [Cycles all ranks are in critical thermal throttle. Unit: uncore_imc]
          uncore_imc_2/event=0x86/  MetricName: power_critical_throttle_cycles % MetricExpr: (unc_m_power_critical_throttle_cycles / unc_m_clockticks) * 100.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lkml.kernel.org/r/20170320201711.14142-14-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-23 11:42:31 -03:00
Andi Kleen 9628481423 perf pmu: Add support for MetricName JSON attribute
Add support for a new JSON event attribute to name MetricExpr for better
output in perf stat.

If the event has no MetricName it uses the normal event name instead to
describe the metric.

Before

  % perf stat -a -I 1000 -e '{unc_p_clockticks,unc_p_freq_max_os_cycles}' --metric-only
           time unc_p_freq_max_os_cycles
     1.000149775     15.7
     2.000344807     19.3
     3.000502544     16.7
     4.000640656      6.6
     5.000779955      9.9

After

  % perf stat -a -I 1000 -e '{unc_p_clockticks,unc_p_freq_max_os_cycles}' --metric-only
           time freq_max_os_cycles %
     1.000149775     15.7
     2.000344807     19.3
     3.000502544     16.7
     4.000640656      6.6
     5.000779955      9.9

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20170320201711.14142-13-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-23 11:42:31 -03:00
Andi Kleen 7f372a636d perf list: Support printing MetricExpr with --debug
Output the metric expr in perf list when --debug is specified, so that
the user can check the formula.

Before:

  % perf list
    ...
    unc_m_power_channel_ppd
         [Cycles where DRAM ranks are in power down (CKE) mode. Derived from unc_m_power_channel_ppd. Unit:
          uncore_imc]
          uncore_imc_2/event=0x85/

After:

  % perf list --debug
    ...
    unc_m_power_channel_ppd
         [Cycles where DRAM ranks are in power down (CKE) mode. Derived from unc_m_power_channel_ppd. Unit:
          uncore_imc]
          Perf: uncore_imc_2/event=0x85/ MetricExpr: (unc_m_power_channel_ppd / unc_m_clockticks) * 100.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20170320201711.14142-12-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-23 11:42:30 -03:00
Andi Kleen 37932c188e perf stat: Output JSON MetricExpr metric
Add generic infrastructure to perf stat to output ratios for
"MetricExpr" entries in the event lists. Many events are more useful as
ratios than in raw form, typically some count in relation to total
ticks.

Transfer the MetricExpr information from the alias to the evsel.

We mark the events that need to be collected for MetricExpr, and also
link the events using them with a pointer. The code is careful to always
prefer the right event in the same group to minimize multiplexing
errors. At the moment only a single relation is supported.

Then add a rblist to the stat shadow code that remembers stats based on
the cpu and context.

Then finally update and retrieve and print these values similarly to the
existing hardcoded perf metrics. We use the simple expression parser
added earlier to evaluate the expression.

Normally we just output the result without further commentary, but for
--metric-only this would lead to empty columns. So for this case use the
original event as description.

There is no attempt to automatically add the MetricExpr event, if it is
missing, however we suggest it to the user, because the user tool
doesn't have enough information to reliably construct a group that is
guaranteed to schedule. So we leave that to the user.

  % perf stat -a -I 1000 -e '{unc_p_clockticks,unc_p_freq_max_os_cycles}'
       1.000147889        800,085,181      unc_p_clockticks
       1.000147889         93,126,241      unc_p_freq_max_os_cycles  #     11.6
       2.000448381        800,218,217      unc_p_clockticks
       2.000448381        142,516,095      unc_p_freq_max_os_cycles  #     17.8
       3.000639852        800,243,057      unc_p_clockticks
       3.000639852        162,292,689      unc_p_freq_max_os_cycles  #     20.3

  % perf stat -a -I 1000 -e '{unc_p_clockticks,unc_p_freq_max_os_cycles}' --metric-only
  #    time         freq_max_os_cycles %
       1.000127077      0.9
       2.000301436      0.7
       3.000456379      0.0

v2: Change from DivideBy to MetricExpr
v3: Use expr__ prefix.  Support more than one other event.
v4: Update description
v5: Only print warning message once for multiple PMUs.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20170320201711.14142-11-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-23 11:42:30 -03:00
Andi Kleen 00636c3b48 perf pmu: Support MetricExpr header in JSON event list
Add support for parsing the MetricExpr header in the JSON event lists
and storing them in the alias structure.

Used in the next patch.

v2: Change DividedBy to MetricExpr
v3: Really catch all uses of DividedBy

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20170320201711.14142-10-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-23 11:42:29 -03:00
Andi Kleen 075167363f perf tools: Add a simple expression parser for JSON
Add a simple expression parser good enough to parse JSON relation
expressions. The parser is implemented using bison.

This is just intended as an simple parser for internal usage in the
event lists, not the beginning of a "perf scripting language"

v2: Use expr__ prefix instead of expr_
    Support multiple free variables for parser

Committer note:

The v2 patch had:

  %define api.pure full

In expr.y, that is a feature introduced in bison 2.7, to have reentrant
parsers, not using global variables, which would make tools/perf stop
building with the bison version shipped in older distros, so Andi
realised that the other parsers (e.g. parse-events.y) were using:

  %pure-parser

Which is present in older versions of bison and fits the bill.

I added:

  CFLAGS_expr-bison.o += -DYYENABLE_NLS=0 -DYYLTYPE_IS_TRIVIAL=0 -w

To finally make it build, copying what was there for pmu-bison.o,
another parser.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20170320201711.14142-8-andi@firstfloor.org
[ stdlib.h is needed in tests/expr.c for free() fixing build in systems such as ubuntu:16.04-x-s390 ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-23 11:39:27 -03:00
Andi Kleen a820e33547 perf pmu: Special case uncore_ prefix
Special case uncore_ prefix in PMU match, to allow for shorter event
uncore specifications.

Before:

  perf stat -a -e uncore_cbox/event=0x35,umask=0x1,filter_opc=0x19C/ sleep 1

After

  perf stat -a -e cbox/event=0x35,umask=0x1,filter_opc=0x19C/ sleep 1

Committer tests:

   # perf list uncore

  List of pre-defined events (to be used in -e):

    uncore_cbox_0/clockticks/                       [Kernel PMU event]
    uncore_cbox_1/clockticks/                       [Kernel PMU event]
    uncore_imc/data_reads/                          [Kernel PMU event]
    uncore_imc/data_writes/                         [Kernel PMU event]

  # perf stat -a -e cbox_0/clockticks/ sleep 1

   Performance counter stats for 'system wide':

  281,474,976,653,084      cbox_0/clockticks/

       1.000870129 seconds time elapsed

  #

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lkml.kernel.org/r/20170320201711.14142-7-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-21 16:10:59 -03:00
Andi Kleen 8255718f4b perf pmu: Expand PMU events by prefix match
When the user specifies a pmu directly, expand it automatically with a
prefix match for all available PMUs, similar as we do for the normal
aliases now.

This allows to specify attributes for duplicated boxes quickly.  For
example uncore_cbox_{0,6}/.../ can be now specified as uncore_cbox/.../
and it gets automatically expanded for all boxes.

This generally makes it more concise to write uncore specifications, and
also avoids the need to know the exact topology of the system.

Before:

  % perf stat -a -e uncore_cbox_0/event=0x35,umask=0x1,filter_opc=0x19C/,\
  uncore_cbox_1/event=0x35,umask=0x1,filter_opc=0x19C/,\
  uncore_cbox_2/event=0x35,umask=0x1,filter_opc=0x19C/,\
  uncore_cbox_3/event=0x35,umask=0x1,filter_opc=0x19C/,\
  uncore_cbox_4/event=0x35,umask=0x1,filter_opc=0x19C/,\
  uncore_cbox_5/event=0x35,umask=0x1,filter_opc=0x19C/ sleep 1

After:

  % perf stat -a -e uncore_cbox/event=0x35,umask=0x1,filter_opc=0x19C/ sleep 1

v2: Handle all bison rules. Move multi add code to separate function.
    Handle uncore_ prefix correctly.
v3: Move parse_events_multi_pmu_add to separate patch. Move uncore
    prefix check to separate patch.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20170320201711.14142-6-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-21 16:08:32 -03:00
Andi Kleen 2073ad3326 perf tools: Factor out PMU matching in parser
Factor out the PMU name matching in the event parser into a separate
function, to use the same code for other grammar rules later.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20170320201711.14142-5-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-21 16:07:40 -03:00
Andi Kleen 430daf2dc7 perf stat: Collapse identically named events
The uncore PMU has a lot of duplicated PMUs for different subsystems.
When expanding an uncore alias we usually end up with a large
number of identically named aliases, which makes perf stat
output difficult to read.

Automatically sum them up in perf stat, unless --no-merge is specified.

This can be default because only the uncores generally have duplicated
aliases. Other PMUs have unique names.

Before:

  % perf stat --no-merge -a -e unc_c_llc_lookup.any sleep 1

  Performance counter stats for 'system wide':

           694,976 Bytes unc_c_llc_lookup.any
           706,304 Bytes unc_c_llc_lookup.any
           956,608 Bytes unc_c_llc_lookup.any
           782,720 Bytes unc_c_llc_lookup.any
           605,696 Bytes unc_c_llc_lookup.any
           442,816 Bytes unc_c_llc_lookup.any
           659,328 Bytes unc_c_llc_lookup.any
           509,312 Bytes unc_c_llc_lookup.any
           263,936 Bytes unc_c_llc_lookup.any
           592,448 Bytes unc_c_llc_lookup.any
           672,448 Bytes unc_c_llc_lookup.any
           608,640 Bytes unc_c_llc_lookup.any
           641,024 Bytes unc_c_llc_lookup.any
           856,896 Bytes unc_c_llc_lookup.any
           808,832 Bytes unc_c_llc_lookup.any
           684,864 Bytes unc_c_llc_lookup.any
           710,464 Bytes unc_c_llc_lookup.any
           538,304 Bytes unc_c_llc_lookup.any

       1.002577660 seconds time elapsed

After:

  % perf stat -a -e unc_c_llc_lookup.any sleep 1

  Performance counter stats for 'system wide':

         2,685,120 Bytes unc_c_llc_lookup.any

       1.002648032 seconds time elapsed

v2: Split collect_aliases. Rename alias flag.
v3: Make sure unsupported/not counted is always printed.
v4: Factor out callback change into separate patch.
v5: Move check for bad results here
    Move merged check into collect_data

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20170320201711.14142-3-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-21 16:04:11 -03:00
Arnaldo Carvalho de Melo ed7b339fb5 perf annotate: Add comment clarifying how the source code line is parsed
The source code line number (lineno) needs to be kept in accross calls
to symbol__parse_objdump_line() when parsing the output of 'objdump -l
-dS', so that it can associate it with the instructions till the next
line.

See disasm_line__new() and struct disasm_line::line_nr.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Taeung Song <treeze.taeung@gmail.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-7hpx8f8ybdpiujceysaj229w@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-21 16:00:50 -03:00
Taeung Song e7cb9de211 perf annotate: More exactly grep -v of the objdump command
The 'grep -v "filename"' applied to the objdump command output cause a
side effect eliminating filename:linenr of output of 'objdump -l' if the
object file name and source file name are the same, fix it.

E.g. the output of the following objdump command in symbol__disassemble():

    $ objdump -l -d -S -C /home/taeung/hello --start-address=...

    /home/taeung/hello:     file format elf64-x86-64

    Disassembly of section .text:

    0000000000400526 <main>:
    main():
    /home/taeung/hello.c:4

    void main()
    {
      400526:	55                   	push   %rbp
      400527:	48 89 e5             	mov    %rsp,%rbp
    /home/taeung/hello.c:5
    ...

But it uses grep -v "filename" e.g. "/home/taeung/hello" in the objdump
command to remove the first line containing file name and file format
("/home/taeung/hello:     file format elf64-x86-64"):

Before:

    $ objdump -l -d -S -C /home/taeung/hello | grep /home/taeung/hello

But this causes a side effect, removing filename:linenr too, because the
object file and source file have the same name e.g. "/home/taueng/hello",
"/home/taeung/hello.c"

So more do a better match by using grep -v as below to correctly remove
that first line:

    "/home/taeung/hello:     file format elf64-x86-64"

After:

    $ objdump -l -d -S -C /home/taeung/hello | grep /home/taeung/hello:

Signed-off-by: Taeung Song <treeze.taeung@gmail.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1489978617-31396-5-git-send-email-treeze.taeung@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-21 15:42:25 -03:00
Alexis Berlemont 3b1f8311f6 perf probe: Add sdt probes arguments into the uprobe cmd string
An sdt probe can be associated with arguments but they were not passed
to the user probe tracing interface (uprobe_events); this patch adapts
the sdt argument descriptors according to the uprobe input format.

As the uprobe parser does not support scaled address mode, perf will
skip arguments which cannot be adapted to the uprobe format.

Here are the results:

  $ perf buildid-cache -v --add test_sdt
  $ perf probe -x test_sdt sdt_libfoo:table_frob
  $ perf probe -x test_sdt sdt_libfoo:table_diddle
  $ perf record -e sdt_libfoo:table_frob -e sdt_libfoo:table_diddle test_sdt
  $ perf script
  test_sdt  ...   666.255678:   sdt_libfoo:table_frob: (4004d7) arg0=0 arg1=0
  test_sdt  ...   666.255683: sdt_libfoo:table_diddle: (40051a) arg0=0 arg1=0
  test_sdt  ...   666.255686:   sdt_libfoo:table_frob: (4004d7) arg0=1 arg1=2
  test_sdt  ...   666.255689: sdt_libfoo:table_diddle: (40051a) arg0=3 arg1=4
  test_sdt  ...   666.255692:   sdt_libfoo:table_frob: (4004d7) arg0=2 arg1=4
  test_sdt  ...   666.255694: sdt_libfoo:table_diddle: (40051a) arg0=6 arg1=8

Signed-off-by: Alexis Berlemont <alexis.berlemont@gmail.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20161214000732.1710-3-alexis.berlemont@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-21 10:59:01 -03:00
Alexis Berlemont be88184b1c perf sdt: Add scanning of sdt probes arguments
During a "perf buildid-cache --add" command, the section ".note.stapsdt"
of the "added" binary is scanned in order to list the available SDT
markers available in a binary. The parts containing the probes arguments
were left unscanned.

The whole section is now parsed; the probe arguments are extracted for
later use.

Signed-off-by: Alexis Berlemont <alexis.berlemont@gmail.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20161214000732.1710-2-alexis.berlemont@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-21 10:56:28 -03:00
Ravi Bangoria 2e1f8f7895 perf probe: Change MAX_CMDLEN
There are many SDT markers in powerpc whose uprobe definition goes
beyond current MAX_CMDLEN, especially when target filename is long and
sdt marker has long list of arguments. For example, definition of sdt
marker

  method__compile__end: 8@17 8@9 8@10 -4@8 8@7 -4@6 8@5 -4@4 1@37(28)

from file

  /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.91-2.b14.fc22.ppc64/jre/lib/ppc64/server/libjvm.so

is

  p:sdt_hotspot/method__compile__end /usr/lib/jvm/java-1.8.0-openjdk-\
    1.8.0.91-2.b14.fc22.ppc64/jre/lib/ppc64/server/libjvm.so:0x4c4e00\
    arg1=%gpr17:u64 arg2=%gpr9:u64 arg3=%gpr10:u64 arg4=%gpr8:s32\
    arg5=%gpr7:u64 arg6=%gpr6:s32 arg7=%gpr5:u64 arg8=%gpr4:s32\
    arg9=+37(%gpr28):u8

'perf probe' fails with segfault for such markers. As the uprobe_events
file accepts definitions up to 4094 characters(4096 - 2 (\n\0)),
increase value of MAX_CMDLEN match that.

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexis Berlemont <alexis.berlemont@gmail.com>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170207054547.3690-1-ravi.bangoria@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-21 10:34:59 -03:00
Ravi Bangoria f0a30dca5f perf probe: Fix concat_probe_trace_events
'*ntevs' contains number of elements present in 'tevs' array. If there
are no elements in array, 'tevs2' can be directly assigned to 'tevs'
without allocating more space. So the condition should be  '*ntevs == 0'
not  'ntevs == 0'.

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes: 42bba263eb ("perf probe: Allow wildcard for cached events")
Link: http://lkml.kernel.org/r/20170308065908.4128-1-ravi.bangoria@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-20 15:01:32 -03:00
Alexander Shishkin 05a1f47ed4 perf tools: Handle partial AUX records and print a warning
This patch decodes the 'partial' flag in AUX records and prints
a warning to the user, so that they don't have to guess why their
PT traces contain gaps (or missing altogether):

  Warning:
  AUX data had gaps in it 8 times out of 8!

  Are you running a KVM guest in the background?

Trying to be even more helpful, we will detect if the user's kvm driver sets up
exclusive VMX root mode for the entire lifespan of the kvm process:

  Reloading kvm_intel module with vmm_exclusive=0
  will reduce the gaps to only guest's timeslices.

Note however, that you'll still have gaps in cpu-wide traces even with
vmm_exclusive=0, but the number of gaps will be below 100% (as opposed to the
above example).

Currently this is the only reason for partial records.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vince Weaver <vince@deater.net>
Link: http://lkml.kernel.org/r/8760j941ig.fsf@ashishki-desk.ger.corp.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-17 11:52:18 -03:00
Daniel Borkmann e7ede72a6d perf symbols: Fix symbols__fixup_end heuristic for corner cases
The current symbols__fixup_end() heuristic for the last entry in the rb
tree is suboptimal as it leads to not being able to recognize the symbol
in the call graph in a couple of corner cases, for example:

 i) If the symbol has a start address (f.e. exposed via kallsyms)
    that is at a page boundary, then the roundup(curr->start, 4096)
    for the last entry will result in curr->start == curr->end with
    a symbol length of zero.

ii) If the symbol has a start address that is shortly before a page
    boundary, then also here, curr->end - curr->start will just be
    very few bytes, where it's unrealistic that we could perform a
    match against.

Instead, change the heuristic to roundup(curr->start, 4096) + 4096, so
that we can catch such corner cases and have a better chance to find
that specific symbol. It's still just best effort as the real end of the
symbol is unknown to us (and could even be at a larger offset than the
current range), but better than the current situation.

Alexei reported that he recently run into case i) with a JITed eBPF
program (these are all page aligned) as the last symbol which wasn't
properly shown in the call graph (while other eBPF program symbols in
the rb tree were displayed correctly). Since this is a generic issue,
lets try to improve the heuristic a bit.

Reported-and-Tested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Fixes: 2e538c4a18 ("perf tools: Improve kernel/modules symbol lookup")
Link: http://lkml.kernel.org/r/bb5c80d27743be6f12afc68405f1956a330e1bc9.1489614365.git.daniel@iogearbox.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-17 10:30:22 -03:00
Ingo Molnar 61f63e3837 perf/core improvements and fixes:
New features:
 
 - Add 'brstackinsn' field in 'perf script' to reuse the x86 instruction
   decoder used in the Intel PT code to study hot paths to samples (Andi Kleen)
 
 Kernel:
 
 - Default UPROBES_EVENTS to Y (Alexei Starovoitov)
 
 - Fix check for kretprobe offset within function entry (Naveen N. Rao)
 
 Infrastructure:
 
 - Introduce util func is_sdt_event() (Ravi Bangoria)
 
 - Make perf_event__synthesize_mmap_events() scale on older kernels where
   reading /proc/pid/maps is way slower than reading /proc/pid/task/pid/maps (Stephane Eranian)
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-core-for-mingo-4.12-20170316' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:

New features:

 - Add 'brstackinsn' field in 'perf script' to reuse the x86 instruction
   decoder used in the Intel PT code to study hot paths to samples (Andi Kleen)

Kernel changes:

 - Default UPROBES_EVENTS to Y (Alexei Starovoitov)

 - Fix check for kretprobe offset within function entry (Naveen N. Rao)

Infrastructure changes:

 - Introduce util func is_sdt_event() (Ravi Bangoria)

 - Make perf_event__synthesize_mmap_events() scale on older kernels where
   reading /proc/pid/maps is way slower than reading /proc/pid/task/pid/maps (Stephane Eranian)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-16 17:29:23 +01:00