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  1. 23 3月, 2016 2 次提交
  3. 05 2月, 2016 1 次提交
  5. 12 1月, 2016 1 次提交
  7. 18 12月, 2015 14 次提交
  9. 07 10月, 2015 1 次提交
  11. 01 10月, 2015 2 次提交
  13. 29 9月, 2015 1 次提交
    • A
      perf tools: Use __map__is_kernel() when synthesizing kernel module mmap records · ab9c2bdc
      由 Arnaldo Carvalho de Melo 提交于 
      Equivalent and removes one more case of using dso->kernel.

  # perf record -a usleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.768 MB perf.data (30 samples) ]

Before:

  [root@zoo ~]# perf script --show-task --show-mmap | head -3
   swapper 0 [0] 0.0: PERF_RECORD_MMAP -1/0: [0xffffffff81000000(0x1f000000) @ 0xffffffff81000000]: x [kernel.kallsyms]_text
   swapper 0 [0] 0.0: PERF_RECORD_MMAP -1/0: [0xffffffffa0000000(0xa000) @ 0]: x /lib/modules/4.3.0-rc1+/kernel/drivers/acpi/video.ko
   swapper 0 [0] 0.0: PERF_RECORD_MMAP -1/0: [0xffffffffa000a000(0x5000) @ 0]: x /lib/modules/4.3.0-rc1+/kernel/drivers/i2c/algos/i2c-algo-bit.ko
  #

  # perf script --show-task --show-mmap | head -3
   swapper 0 [0] 0.0: PERF_RECORD_MMAP -1/0: [0xffffffff81000000(0x1f000000) @ 0xffffffff81000000]: x [kernel.kallsyms]_text
   swapper 0 [0] 0.0: PERF_RECORD_MMAP -1/0: [0xffffffffa0000000(0xa000) @ 0]: x /lib/modules/4.3.0-rc1+/kernel/drivers/acpi/video.ko
   swapper 0 [0] 0.0: PERF_RECORD_MMAP -1/0: [0xffffffffa000a000(0x5000) @ 0]: x /lib/modules/4.3.0-rc1+/kernel/drivers/i2c/algos/i2c-algo-bit.ko
  #

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-b65xe578dwq22mzmmj5y94wr@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      ab9c2bdc
  15. 23 9月, 2015 1 次提交
    • N
      perf record: Synthesize COMM event for a command line workload · e803cf97
      由 Namhyung Kim 提交于 
      When perf creates a new child to profile, the events are enabled on
exec().  And in this case, it doesn't synthesize any event for the
child since they'll be generated during exec().  But there's an window
between the enabling and the event generation.

It used to be overcome since samples are only in kernel (so we always
have the map) and the comm is overridden by a later COMM event.
However it won't work if events are processed and displayed before the
COMM event overrides like in 'perf script'.  This leads to those early
samples (like native_write_msr_safe) not having a comm but pid (like
':15328').

So it needs to synthesize COMM event for the child explicitly before
enabling so that it can have a correct comm.  But at this time, the
comm will be "perf" since it's not exec-ed yet.

Committer note:

Before this patch:

  # perf record usleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.017 MB perf.data (7 samples) ]
  # perf script --show-task-events
    :4429  4429 27909.079372:          1 cycles:  ffffffff8105f45a native_write_msr_safe (/lib/modules/4.
    :4429  4429 27909.079375:          1 cycles:  ffffffff8105f45a native_write_msr_safe (/lib/modules/4.
    :4429  4429 27909.079376:         10 cycles:  ffffffff8105f45a native_write_msr_safe (/lib/modules/4.
    :4429  4429 27909.079377:        223 cycles:  ffffffff8105f45a native_write_msr_safe (/lib/modules/4.
    :4429  4429 27909.079378:       6571 cycles:  ffffffff8105f45a native_write_msr_safe (/lib/modules/4.
   usleep  4429 27909.079380: PERF_RECORD_COMM exec: usleep:4429/4429
   usleep  4429 27909.079381:     185403 cycles:  ffffffff810a72d3 flush_signal_handlers (/lib/modules/4.
   usleep  4429 27909.079444:    2241110 cycles:      7fc575355be3 _dl_start (/usr/lib64/ld-2.20.so)
   usleep  4429 27909.079875: PERF_RECORD_EXIT(4429:4429):(4429:4429)

After:

  # perf record usleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.017 MB perf.data (7 samples) ]
  # perf script --show-task
     perf     0     0.000000: PERF_RECORD_COMM: perf:8446/8446
     perf  8446 30154.038944:          1 cycles:  ffffffff8105f45a native_write_msr_safe (/lib/modules/4.
     perf  8446 30154.038948:          1 cycles:  ffffffff8105f45a native_write_msr_safe (/lib/modules/4.
     perf  8446 30154.038949:          9 cycles:  ffffffff8105f45a native_write_msr_safe (/lib/modules/4.
     perf  8446 30154.038950:        230 cycles:  ffffffff8105f45a native_write_msr_safe (/lib/modules/4.
     perf  8446 30154.038951:       6772 cycles:  ffffffff8105f45a native_write_msr_safe (/lib/modules/4.
   usleep  8446 30154.038952: PERF_RECORD_COMM exec: usleep:8446/8446
   usleep  8446 30154.038954:     196923 cycles:  ffffffff81766440 _raw_spin_lock (/lib/modules/4.3.0-rc1
   usleep  8446 30154.039021:    2292130 cycles:      7f609a173dc4 memcpy (/usr/lib64/ld-2.20.so)
   usleep  8446 30154.039349: PERF_RECORD_EXIT(8446:8446):(8446:8446)
  #
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1442881495-2928-1-git-send-email-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      e803cf97
  17. 14 9月, 2015 1 次提交
  19. 24 7月, 2015 1 次提交
  21. 24 6月, 2015 1 次提交
  23. 20 6月, 2015 2 次提交
  25. 07 6月, 2015 1 次提交
    • K
      perf tools: handle PERF_RECORD_LOST_SAMPLES · c4937a91
      由 Kan Liang 提交于 
      This patch modifies the perf tool to handle the new RECORD type,
PERF_RECORD_LOST_SAMPLES.

The number of lost-sample events is stored in
.nr_events[PERF_RECORD_LOST_SAMPLES]. The exact number of samples
which the kernel dropped is stored in total_lost_samples.

When the percentage of dropped samples is greater than 5%, a warning
is printed.

Here are some examples:

Eg 1, Recording different frequently-occurring events is safe with the
      patch. Only a very low drop rate is associated with such actions.

$ perf record -e '{cycles:p,instructions:p}' -c 20003 --no-time ~/tchain ~/tchain

$ perf report -D | tail
          SAMPLE events:     120243
           MMAP2 events:          5
    LOST_SAMPLES events:         24
  FINISHED_ROUND events:         15
cycles:p stats:
           TOTAL events:      59348
          SAMPLE events:      59348
instructions:p stats:
           TOTAL events:      60895
          SAMPLE events:      60895

$ perf report --stdio --group
 # To display the perf.data header info, please use --header/--header-only options.
 #
 #
 # Total Lost Samples: 24
 #
 # Samples: 120K of event 'anon group { cycles:p, instructions:p }'
 # Event count (approx.): 24048600000
 #
 #         Overhead  Command      Shared Object     Symbol
 # ................  ...........  ................
 ..................................
 #
    99.74%  99.86%  tchain_edit  tchain_edit       [.] f3
     0.09%   0.02%  tchain_edit  tchain_edit       [.] f2
     0.04%   0.00%  tchain_edit  [kernel.vmlinux]  [k] ixgbe_read_reg

Eg 2, Recording the same thing multiple times can lead to high drop
      rate, but it is not a useful configuration.

$ perf record -e '{cycles:p,cycles:p}' -c 20003 --no-time ~/tchain
Warning: Processed 600592 samples and lost 99.73% samples!
[perf record: Woken up 148 times to write data]
[perf record: Captured and wrote 36.922 MB perf.data (1206322 samples)]
[perf record: Woken up 1 times to write data]
[perf record: Captured and wrote 0.121 MB perf.data (1629 samples)]
Signed-off-by: NKan Liang <kan.liang@intel.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@infradead.org
Cc: eranian@google.com
Link: http://lkml.kernel.org/r/1431285195-14269-9-git-send-email-kan.liang@intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      c4937a91
  27. 28 5月, 2015 1 次提交
  29. 27 5月, 2015 1 次提交
  31. 09 5月, 2015 1 次提交
    • A
      perf machine: Protect the machine->threads with a rwlock · b91fc39f
      由 Arnaldo Carvalho de Melo 提交于 
      In addition to using refcounts for the struct thread lifetime
management, we need to protect access to machine->threads from
concurrent access.

That happens in 'perf top', where a thread processes events, inserting
and deleting entries from that rb_tree while another thread decays
hist_entries, that end up dropping references and ultimately deleting
threads from the rb_tree and releasing its resources when no further
hist_entry (or other data structures, like in 'perf sched') references
it.

So the rule is the same for refcounts + protected trees in the kernel,
get the tree lock, find object, bump the refcount, drop the tree lock,
return, use object, drop the refcount if no more use of it is needed,
keep it if storing it in some other data structure, drop when releasing
that data structure.

I.e. pair "t = machine__find(new)_thread()" with a "thread__put(t)", and
"perf_event__preprocess_sample(&al)" with "addr_location__put(&al)".

The addr_location__put() one is because as we return references to
several data structures, we may end up adding more reference counting
for the other data structures and then we'll drop it at
addr_location__put() time.
Acked-by: NDavid Ahern <dsahern@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-bs9rt4n0jw3hi9f3zxyy3xln@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      b91fc39f
  33. 06 5月, 2015 2 次提交
  35. 29 4月, 2015 2 次提交
  37. 10 4月, 2015 2 次提交
  39. 01 4月, 2015 2 次提交