<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/tools/perf/Documentation, branch linux-4.17.y</title>
<subtitle>Hosts the 0x221E linux distro kernel.</subtitle>
<id>https://universe.0xinfinity.dev/distro/kernel/atom?h=linux-4.17.y</id>
<link rel='self' href='https://universe.0xinfinity.dev/distro/kernel/atom?h=linux-4.17.y'/>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/'/>
<updated>2018-05-30T18:40:26Z</updated>
<entry>
<title>perf tools: Fix perf.data format description of NRCPUS header</title>
<updated>2018-05-30T18:40:26Z</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2018-05-25T19:37:36Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=18a7057420f8b67f15d17087bf5c0863db752c8b'/>
<id>urn:sha1:18a7057420f8b67f15d17087bf5c0863db752c8b</id>
<content type='text'>
In the perf.data HEADER_CPUDESC feadure header we store first the number
of available CPUs in the system, then the number of CPUs at the time of
writing the header, not the other way around.

Reported-by: Thomas-Mich Richter &lt;tmricht@linux.ibm.com&gt;
Acked-by: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: He Kuang &lt;hekuang@huawei.com&gt;
Cc: Hendrik Brueckner &lt;brueckner@linux.vnet.ibm.com&gt;
Cc: Jin Yao &lt;yao.jin@linux.intel.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Kim Phillips &lt;kim.phillips@arm.com&gt;
Cc: Lakshman Annadorai &lt;lakshmana@google.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Simon Que &lt;sque@chromium.org&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Link: https://lkml.kernel.org/n/tip-j7o92acm2vnxjv70y4o3swoc@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf data: Update documentation section on cpu topology</title>
<updated>2018-05-30T18:39:13Z</updated>
<author>
<name>Thomas Richter</name>
<email>tmricht@linux.ibm.com</email>
</author>
<published>2018-05-28T07:44:33Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=0c711138fa61188aa379210e9e08ac76838dea03'/>
<id>urn:sha1:0c711138fa61188aa379210e9e08ac76838dea03</id>
<content type='text'>
Add an explanation of each cpu's core and socket identifier to the
perf.data file format documentation.

Signed-off-by: Thomas Richter &lt;tmricht@linux.ibm.com&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Hendrik Brueckner &lt;brueckner@linux.vnet.ibm.com&gt;
Cc: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Link: http://lkml.kernel.org/r/20180528074433.16652-1-tmricht@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf mem: Document incorrect and missing options</title>
<updated>2018-04-23T14:59:18Z</updated>
<author>
<name>Sangwon Hong</name>
<email>qpakzk@gmail.com</email>
</author>
<published>2018-04-22T07:29:06Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=3138a2ef62667b6ac8eb5fb33a9e0b84ec3ab165'/>
<id>urn:sha1:3138a2ef62667b6ac8eb5fb33a9e0b84ec3ab165</id>
<content type='text'>
Several options were incorrectly described, some lacked describing
required arguments while others were simply not documented, fix it.

Signed-off-by: Sangwon Hong &lt;qpakzk@gmail.com&gt;
Acked-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Taeung Song &lt;treeze.taeung@gmail.com&gt;
Link: http://lkml.kernel.org/r/1524382146-19609-1-git-send-email-qpakzk@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf mem: Allow all record/report options</title>
<updated>2018-04-18T18:35:48Z</updated>
<author>
<name>Andi Kleen</name>
<email>ak@linux.intel.com</email>
</author>
<published>2018-04-06T20:38:09Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=a7e9eab3dbd35268c16244557a4155a2d9a641c3'/>
<id>urn:sha1:a7e9eab3dbd35268c16244557a4155a2d9a641c3</id>
<content type='text'>
For perf mem report / perf mem record, pass all unknown options
through to the underlying report/record commands. This makes things
like

perf mem record -a sleep 1

work. Matches how c2c and other tools work.

Signed-off-by: Andi Kleen &lt;ak@linux.intel.com&gt;
Acked-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Link: http://lkml.kernel.org/r/20180406203812.3087-2-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf script: Extend misc field decoding with switch out event type</title>
<updated>2018-04-17T12:47:39Z</updated>
<author>
<name>Alexey Budankov</name>
<email>alexey.budankov@linux.intel.com</email>
</author>
<published>2018-04-09T07:26:46Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=bf30cc1882d2c65aaf92842cc9bcf06565eab73c'/>
<id>urn:sha1:bf30cc1882d2c65aaf92842cc9bcf06565eab73c</id>
<content type='text'>
Append 'p' sign to 'S' tag designating the type of context switch out event so
'Sp' means preemption context switch. Documentation is extended to cover
new presentation changes.

  $ perf script --show-switch-events -F +misc -I -i perf.data:

          hdparm 4073 [004] U  762.198265:     380194 cycles:ppp:      7faf727f5a23 strchr (/usr/lib64/ld-2.26.so)
          hdparm 4073 [004] K  762.198366:     441572 cycles:ppp:  ffffffffb9218435 alloc_set_pte (/lib/modules/4.16.0-rc6+/build/vmlinux)
          hdparm 4073 [004] S  762.198391: PERF_RECORD_SWITCH_CPU_WIDE OUT          next pid/tid:    0/0
         swapper    0 [004]    762.198392: PERF_RECORD_SWITCH_CPU_WIDE IN           prev pid/tid: 4073/4073
         swapper    0 [004] Sp 762.198477: PERF_RECORD_SWITCH_CPU_WIDE OUT preempt  next pid/tid: 4073/4073
          hdparm 4073 [004]    762.198478: PERF_RECORD_SWITCH_CPU_WIDE IN           prev pid/tid:    0/0
         swapper    0 [007] K  762.198514:    2303073 cycles:ppp:  ffffffffb98b0c66 intel_idle (/lib/modules/4.16.0-rc6+/build/vmlinux)
         swapper    0 [007] Sp 762.198561: PERF_RECORD_SWITCH_CPU_WIDE OUT preempt  next pid/tid: 1134/1134
  kworker/u16:18 1134 [007]    762.198562: PERF_RECORD_SWITCH_CPU_WIDE IN           prev pid/tid:    0/0
  kworker/u16:18 1134 [007] S  762.198567: PERF_RECORD_SWITCH_CPU_WIDE OUT          next pid/tid:    0/0

Signed-off-by: Alexey Budankov &lt;alexey.budankov@linux.intel.com&gt;
Tested-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: http://lkml.kernel.org/r/5fc65ce7-8ca5-53ae-8858-8ddd27290575@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf annotate: Allow setting the offset level in .perfconfig</title>
<updated>2018-04-13T13:00:05Z</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2018-04-12T18:23:02Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=43c4023152a9c5742948ac919e58ade127fa4e2e'/>
<id>urn:sha1:43c4023152a9c5742948ac919e58ade127fa4e2e</id>
<content type='text'>
The default is 1 (jump_target):

  # perf annotate --ignore-vmlinux --stdio2 _raw_spin_lock_irqsave
  Samples: 3K of event 'cycles:ppp', 3000 Hz, Event count (approx.): 2766398574
  _raw_spin_lock_irqsave() /proc/kcore
    0.26        nop
    4.61        push   %rbx
   19.33        pushfq
    7.97        pop    %rax
    0.32        nop
    0.06        mov    %rax,%rbx
   14.63        cli
    0.06        nop
                xor    %eax,%eax
                mov    $0x1,%edx
   49.94        lock   cmpxchg %edx,(%rdi)
    0.16        test   %eax,%eax
              ↓ jne    2b
    2.66        mov    %rbx,%rax
                pop    %rbx
              ← retq
          2b:   mov    %eax,%esi
              → callq  *ffffffffb30eaed0
                mov    %rbx,%rax
                pop    %rbx
              ← retq
  #

But one can ask for showing offsets for call instructions by setting
this:

  # perf annotate --ignore-vmlinux --stdio2 _raw_spin_lock_irqsave
  Samples: 3K of event 'cycles:ppp', 3000 Hz, Event count (approx.): 2766398574
  _raw_spin_lock_irqsave() /proc/kcore
    0.26        nop
    4.61        push   %rbx
   19.33        pushfq
    7.97        pop    %rax
    0.32        nop
    0.06        mov    %rax,%rbx
   14.63        cli
    0.06        nop
                xor    %eax,%eax
                mov    $0x1,%edx
   49.94        lock   cmpxchg %edx,(%rdi)
    0.16        test   %eax,%eax
              ↓ jne    2b
    2.66        mov    %rbx,%rax
                pop    %rbx
              ← retq
          2b:   mov    %eax,%esi
          2d: → callq  *ffffffffb30eaed0
                mov    %rbx,%rax
                pop    %rbx
              ← retq
  #

Or using a big value to ask for all offsets to be shown:

  # cat ~/.perfconfig
  [annotate]

	offset_level = 100

	hide_src_code = true
  # perf annotate --ignore-vmlinux --stdio2 _raw_spin_lock_irqsave
  Samples: 3K of event 'cycles:ppp', 3000 Hz, Event count (approx.): 2766398574
  _raw_spin_lock_irqsave() /proc/kcore
    0.26   0:   nop
    4.61   5:   push   %rbx
   19.33   6:   pushfq
    7.97   7:   pop    %rax
    0.32   8:   nop
    0.06   d:   mov    %rax,%rbx
   14.63  10:   cli
    0.06  11:   nop
          17:   xor    %eax,%eax
          19:   mov    $0x1,%edx
   49.94  1e:   lock   cmpxchg %edx,(%rdi)
    0.16  22:   test   %eax,%eax
          24: ↓ jne    2b
    2.66  26:   mov    %rbx,%rax
          29:   pop    %rbx
          2a: ← retq
          2b:   mov    %eax,%esi
          2d: → callq  *ffffffffb30eaed0
          32:   mov    %rbx,%rax
          35:   pop    %rbx
          36: ← retq
   #

This also affects the TUI, i.e. the default 'perf annotate' and 'perf
top/report' -&gt; A hotkey -&gt; annotate interfaces, when slang-devel is present
in the build, i.e.:

  # perf version --build-options | grep slang
              libslang: [ on  ]  # HAVE_SLANG_SUPPORT
  #

Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Jin Yao &lt;yao.jin@linux.intel.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Martin Liška &lt;mliska@suse.cz&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Ravi Bangoria &lt;ravi.bangoria@linux.vnet.ibm.com&gt;
Cc: Thomas Richter &lt;tmricht@linux.vnet.ibm.com&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Link: https://lkml.kernel.org/n/tip-venm6x5zrt40eu8hxdsmqxz6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf sched: Fix documentation for timehist</title>
<updated>2018-04-12T13:33:36Z</updated>
<author>
<name>Takuya Yamamoto</name>
<email>tkydevel@gmail.com</email>
</author>
<published>2018-04-10T14:35:39Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=e8103e44cebe2ef891bc3a5c6c4b74854846968b'/>
<id>urn:sha1:e8103e44cebe2ef891bc3a5c6c4b74854846968b</id>
<content type='text'>
Fixed a incorrect option and usage to those shown by "perf sched timehist -h",
i.e. the default is really --call-graph, which is equivalent to -g.

Signed-off-by: Takuya Yamamoto &lt;tkydevel@gmail.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: https://lkml.kernel.org/n/tip-8fzo0dlsi1mku5aqx8brep5s@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf stat: Enable 1ms interval for printing event counters values</title>
<updated>2018-04-12T12:29:31Z</updated>
<author>
<name>Alexey Budankov</name>
<email>alexey.budankov@linux.intel.com</email>
</author>
<published>2018-04-03T18:18:33Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=9dc9a95f03a69ab926d9ff1986ab2087f34a5dce'/>
<id>urn:sha1:9dc9a95f03a69ab926d9ff1986ab2087f34a5dce</id>
<content type='text'>
Currently print count interval for performance counters values is
limited by 10ms so reading the values at frequencies higher than 100Hz
is restricted by the tool.

This change makes perf stat -I possible on frequencies up to 1KHz and,
to some extent, makes perf stat -I to be on-par with perf record
sampling profiling.

When running perf stat -I for monitoring e.g. PCIe uncore counters and
at the same time profiling some I/O workload by perf record e.g. for
cpu-cycles and context switches, it is then possible to observe
consolidated CPU/OS/IO(Uncore) performance picture for that workload.

Tool overhead warning printed when specifying -v option can be missed
due to screen scrolling in case you have output to the console
so message is moved into help available by running perf stat -h.

Signed-off-by: Alexey Budankov &lt;alexey.budankov@linux.intel.com&gt;
Acked-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: http://lkml.kernel.org/r/b842ad6a-d606-32e4-afe5-974071b5198e@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf version: Add man page</title>
<updated>2018-04-02T16:52:23Z</updated>
<author>
<name>Jin Yao</name>
<email>yao.jin@linux.intel.com</email>
</author>
<published>2018-03-30T09:27:16Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=709846725673a944ee38da1c275a6dfbf0576d0f'/>
<id>urn:sha1:709846725673a944ee38da1c275a6dfbf0576d0f</id>
<content type='text'>
Since a new option '--build-options' is created for 'perf version', so
we need to document it.

Signed-off-by: Jin Yao &lt;yao.jin@linux.intel.com&gt;
Acked-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Jin Yao &lt;yao.jin@intel.com&gt;
Cc: Kan Liang &lt;kan.liang@intel.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: http://lkml.kernel.org/r/1522402036-22915-7-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf trace: Show only failing syscalls</title>
<updated>2018-04-02T10:57:37Z</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2018-03-29T15:22:59Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=0a6545bda2756807a089c64352edfc5628c57e6c'/>
<id>urn:sha1:0a6545bda2756807a089c64352edfc5628c57e6c</id>
<content type='text'>
For instance:

  # perf probe "vfs_getname=getname_flags:72 pathname=result-&gt;name:string"
  Added new event:
    probe:vfs_getname    (on getname_flags:72 with pathname=result-&gt;name:string)

  You can now use it in all perf tools, such as:

	  perf record -e probe:vfs_getname -aR sleep 1

  # perf trace --failure sleep 1
     0.043 ( 0.010 ms): sleep/10978 access(filename: /etc/ld.so.preload, mode: R) = -1 ENOENT No such file or directory

For reference, here are all the syscalls in this case:

  # perf trace sleep 1
         ? (         ): sleep/10976  ... [continued]: execve()) = 0
       0.027 ( 0.001 ms): sleep/10976 brk() = 0x55bdc2d04000
       0.044 ( 0.010 ms): sleep/10976 access(filename: /etc/ld.so.preload, mode: R) = -1 ENOENT No such file or directory
       0.057 ( 0.006 ms): sleep/10976 openat(dfd: CWD, filename: /etc/ld.so.cache, flags: CLOEXEC) = 3
       0.064 ( 0.002 ms): sleep/10976 fstat(fd: 3, statbuf: 0x7fffac22b370) = 0
       0.067 ( 0.003 ms): sleep/10976 mmap(len: 111457, prot: READ, flags: PRIVATE, fd: 3) = 0x7feec8615000
       0.071 ( 0.001 ms): sleep/10976 close(fd: 3) = 0
       0.080 ( 0.007 ms): sleep/10976 openat(dfd: CWD, filename: /lib64/libc.so.6, flags: CLOEXEC) = 3
       0.088 ( 0.002 ms): sleep/10976 read(fd: 3, buf: 0x7fffac22b538, count: 832) = 832
       0.092 ( 0.001 ms): sleep/10976 fstat(fd: 3, statbuf: 0x7fffac22b3d0) = 0
       0.094 ( 0.002 ms): sleep/10976 mmap(len: 8192, prot: READ|WRITE, flags: PRIVATE|ANONYMOUS) = 0x7feec8613000
       0.099 ( 0.004 ms): sleep/10976 mmap(len: 3889792, prot: EXEC|READ, flags: PRIVATE|DENYWRITE, fd: 3) = 0x7feec8057000
       0.104 ( 0.007 ms): sleep/10976 mprotect(start: 0x7feec8203000, len: 2097152) = 0
       0.112 ( 0.005 ms): sleep/10976 mmap(addr: 0x7feec8403000, len: 24576, prot: READ|WRITE, flags: PRIVATE|DENYWRITE|FIXED, fd: 3, off: 1753088) = 0x7feec8403000
       0.120 ( 0.003 ms): sleep/10976 mmap(addr: 0x7feec8409000, len: 14976, prot: READ|WRITE, flags: PRIVATE|ANONYMOUS|FIXED) = 0x7feec8409000
       0.128 ( 0.001 ms): sleep/10976 close(fd: 3) = 0
       0.139 ( 0.001 ms): sleep/10976 arch_prctl(option: 4098, arg2: 140663540761856) = 0
       0.186 ( 0.004 ms): sleep/10976 mprotect(start: 0x7feec8403000, len: 16384, prot: READ) = 0
       0.204 ( 0.003 ms): sleep/10976 mprotect(start: 0x55bdc0ec3000, len: 4096, prot: READ) = 0
       0.209 ( 0.004 ms): sleep/10976 mprotect(start: 0x7feec8631000, len: 4096, prot: READ) = 0
       0.214 ( 0.010 ms): sleep/10976 munmap(addr: 0x7feec8615000, len: 111457) = 0
       0.269 ( 0.001 ms): sleep/10976 brk() = 0x55bdc2d04000
       0.271 ( 0.002 ms): sleep/10976 brk(brk: 0x55bdc2d25000) = 0x55bdc2d25000
       0.274 ( 0.001 ms): sleep/10976 brk() = 0x55bdc2d25000
       0.278 ( 0.007 ms): sleep/10976 open(filename: /usr/lib/locale/locale-archive, flags: CLOEXEC) = 3
       0.288 ( 0.001 ms): sleep/10976 fstat(fd: 3&lt;/usr/lib/locale/locale-archive&gt;, statbuf: 0x7feec8408aa0) = 0
       0.290 ( 0.003 ms): sleep/10976 mmap(len: 113045344, prot: READ, flags: PRIVATE, fd: 3) = 0x7feec1488000
       0.297 ( 0.001 ms): sleep/10976 close(fd: 3&lt;/usr/lib/locale/locale-archive&gt;) = 0
       0.325 (1000.193 ms): sleep/10976 nanosleep(rqtp: 0x7fffac22c0b0) = 0
    1000.560 ( 0.006 ms): sleep/10976 close(fd: 1) = 0
    1000.573 ( 0.005 ms): sleep/10976 close(fd: 2) = 0
    1000.596 (         ): sleep/10976 exit_group()
  #

And can be done systemwide, etc, with backtraces:

  # perf trace --max-stack=16 --failure sleep 1
     0.048 ( 0.015 ms): sleep/11092 access(filename: /etc/ld.so.preload, mode: R) = -1 ENOENT No such file or directory
                                       __access (inlined)
                                       dl_main (/usr/lib64/ld-2.26.so)
  #

Or for some specific syscalls:

  # perf trace --max-stack=16 -e openat --failure cat /tmp/rien
  cat: /tmp/rien: No such file or directory
       0.251 ( 0.012 ms): cat/11106 openat(dfd: CWD, filename: /tmp/rien) = -1 ENOENT No such file or directory
                                         __libc_open64 (inlined)
                                         main (/usr/bin/cat)
                                         __libc_start_main (/usr/lib64/libc-2.26.so)
                                         _start (/usr/bin/cat)
  #

Look for inotify* syscalls that fail, system wide, for 2 seconds, with backtraces:

  # perf trace -a --max-stack=16 --failure -e inotify* sleep 2
   819.165 ( 0.058 ms): gmain/1724 inotify_add_watch(fd: 8&lt;anon_inode:inotify&gt;, pathname: /home/acme/~, mask: 16789454) = -1 ENOENT No such file or directory
                                       __GI_inotify_add_watch (inlined)
                                       _ik_watch (/usr/lib64/libgio-2.0.so.0.5400.3)
                                       _ip_start_watching (/usr/lib64/libgio-2.0.so.0.5400.3)
                                       im_scan_missing (/usr/lib64/libgio-2.0.so.0.5400.3)
                                       g_timeout_dispatch (/usr/lib64/libglib-2.0.so.0.5400.3)
                                       g_main_context_dispatch (/usr/lib64/libglib-2.0.so.0.5400.3)
                                       g_main_context_iterate.isra.23 (/usr/lib64/libglib-2.0.so.0.5400.3)
                                       g_main_context_iteration (/usr/lib64/libglib-2.0.so.0.5400.3)
                                       glib_worker_main (/usr/lib64/libglib-2.0.so.0.5400.3)
                                       g_thread_proxy (/usr/lib64/libglib-2.0.so.0.5400.3)
                                       start_thread (/usr/lib64/libpthread-2.26.so)
                                       __GI___clone (inlined)
  #

Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Link: https://lkml.kernel.org/n/tip-8f7d3mngaxvi7tlzloz3n7cs@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
</feed>
