linux-toradex.git/tools/perf/Documentation, branch v6.2-rc2

perf lock contention: Add -L/--lock-filter option

2022-12-21T17:52:39+00:00

The -L/--lock-filter option is to filter only given locks.  The locks
can be specified by address or name (if exists).

  $ sudo ./perf lock record -a  sleep 1

  $ sudo ./perf lock con -l
   contended  total wait  max wait  avg wait           address  symbol

          57     1.11 ms  42.83 us  19.54 us  ffff9f4140059000
          15   280.88 us  23.51 us  18.73 us  ffffffff9d007a40  jiffies_lock
           1    20.49 us  20.49 us  20.49 us  ffffffff9d0d50c0  rcu_state
           1     9.02 us   9.02 us   9.02 us  ffff9f41759e9ba0

  $ sudo ./perf lock con -L jiffies_lock,rcu_state
   contended  total wait  max wait  avg wait      type  caller

          15   280.88 us  23.51 us  18.73 us  spinlock  tick_sched_do_timer+0x93
           1    20.49 us  20.49 us  20.49 us  spinlock  __softirqentry_text_start+0xeb

  $ sudo ./perf lock con -L ffff9f4140059000
   contended  total wait  max wait  avg wait      type  caller

          38   779.40 us  42.83 us  20.51 us  spinlock  worker_thread+0x50
          11   216.30 us  39.87 us  19.66 us  spinlock  queue_work_on+0x39
           8   118.13 us  20.51 us  14.77 us  spinlock  kthread+0xe5

Committer testing:

  # uname -a
  Linux quaco 6.0.12-200.fc36.x86_64 #1 SMP PREEMPT_DYNAMIC Thu Dec 8 17:15:53 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux
  # perf lock record
  ^C[ perf record: Woken up 1 times to write data ]
  # perf lock con -L jiffies_lock,rcu_state
   contended   total wait     max wait     avg wait         type   caller

  # perf lock con
   contended   total wait     max wait     avg wait         type   caller

           1      9.06 us      9.06 us      9.06 us     spinlock   call_timer_fn+0x24
  # perf lock con -L call
  ignore unknown symbol: call
   contended   total wait     max wait     avg wait         type   caller

           1      9.06 us      9.06 us      9.06 us     spinlock   call_timer_fn+0x24
  #

Signed-off-by: Namhyung Kim 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Adrian Hunter 
Cc: Blake Jones 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Peter Zijlstra 
Cc: Song Liu 
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20221219201732.460111-5-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf lock contention: Add -Y/--type-filter option

2022-12-21T17:51:04+00:00

The -Y/--type-filter option is to filter the result for specific lock
types only.  It can accept comma-separated values.  Note that it would
accept type names like one in the output.  spinlock, mutex, rwsem:R and
so on.

For RW-variant lock types, it converts the name to the both variants.
In other words, "rwsem" is same as "rwsem:R,rwsem:W".  Also note that
"mutex" has two different encoding - one for sleeping wait, another for
optimistic spinning.  Add "mutex-spin" entry for the lock_type_table so
that we can add it for "mutex" under the table.

  $ sudo ./perf lock record -a -- ./perf bench sched messaging

  $ sudo ./perf lock con -E 5 -Y spinlock
   contended  total wait   max wait  avg wait      type  caller

         802     1.26 ms   11.73 us   1.58 us  spinlock  __wake_up_common_lock+0x62
          13   787.16 us  105.44 us  60.55 us  spinlock  remove_wait_queue+0x14
          12   612.96 us   78.70 us  51.08 us  spinlock  prepare_to_wait+0x27
         114   340.68 us   12.61 us   2.99 us  spinlock  try_to_wake_up+0x1f5
          83   226.38 us    9.15 us   2.73 us  spinlock  folio_lruvec_lock_irqsave+0x5e

Committer notes:

Make get_type_flag() return UINT_MAX for error instad of -1UL, as that
function returns 'unsigned int' and we store the value on a 'unsigned
int' 'flags' variable which makes clang unhappy:

  35    98.23 fedora:37                     : FAIL clang version 15.0.6 (Fedora 15.0.6-1.fc37)
    builtin-lock.c:2012:14: error: result of comparison of constant 18446744073709551615 with expression of type 'unsigned int' is always true [-Werror,-Wtautological-constant-out-of-range-compare]
                            if (flags != -1UL) {
                                ~~~~~ ^  ~~~~
    builtin-lock.c:2021:14: error: result of comparison of constant 18446744073709551615 with expression of type 'unsigned int' is always true [-Werror,-Wtautological-constant-out-of-range-compare]
                            if (flags != -1UL) {
                                ~~~~~ ^  ~~~~
    builtin-lock.c:2037:14: error: result of comparison of constant 18446744073709551615 with expression of type 'unsigned int' is always true [-Werror,-Wtautological-constant-out-of-range-compare]
                            if (flags != -1UL) {
                                ~~~~~ ^  ~~~~
    3 errors generated.

Signed-off-by: Namhyung Kim 
Cc: Adrian Hunter 
Cc: Blake Jones 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Peter Zijlstra 
Cc: Song Liu 
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20221219201732.460111-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Remove group option.

2022-12-14T18:28:18+00:00

The group option predates grouping events using curly braces added in
commit 89efb029502d7f2d ("perf tools: Add support to parse event group
syntax").

The --group option was retained for legacy support (in August
2012) but keeping it adds complexity.

Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Alexey Bayduraev 
Cc: Andi Kleen 
Cc: Anshuman Khandual 
Cc: Athira Jajeev 
Cc: Eelco Chaudron 
Cc: German Gomez 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: Kan Liang 
Cc: Kim Phillips 
Cc: Leo Yan 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Riccardo Mancini 
Cc: Sandipan Das 
Cc: Sean Christopherson 
Cc: Shaomin Deng 
Cc: Stephane Eranian 
Cc: Timothy Hayes 
Cc: Xing Zhengjun 
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20221213232651.1269909-6-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf lock contention: Add -l/--lock-addr option

2022-12-14T14:24:31+00:00

The -l/--lock-addr option is to implement per-lock-instance contention
stat using LOCK_AGGR_ADDR.  It displays lock address and optionally
symbol name if exists.

  $ sudo ./perf lock con -abl sleep 1
   contended   total wait     max wait     avg wait            address   symbol

           1     36.28 us     36.28 us     36.28 us   ffff92615d6448b8
           9     10.91 us      1.84 us      1.21 us   ffffffffbaed50c0   rcu_state
           1     10.49 us     10.49 us     10.49 us   ffff9262ac4f0c80
           8      4.68 us      1.67 us       585 ns   ffffffffbae07a40   jiffies_lock
           3      3.03 us      1.45 us      1.01 us   ffff9262277861e0
           1       924 ns       924 ns       924 ns   ffff926095ba9d20
           1       436 ns       436 ns       436 ns   ffff9260bfda4f60

Signed-off-by: Namhyung Kim 
Cc: Adrian Hunter 
Cc: Blake Jones 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Peter Zijlstra 
Cc: Song Liu 
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20221209190727.759804-4-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf record: Add remaining branch filters: "no_cycles", "no_flags" & "hw_index"

2022-12-14T14:16:12+00:00

This adds all remaining branch filters i.e "no_cycles", "no_flags" and
"hw_index". While here, also updates the documentation.

Signed-off-by: Anshuman Khandual 
Cc: James Clark 
Cc: Peter Zijlstra 
Link: http://lore.kernel.org/lkml/20221205064443.533587-1-anshuman.khandual@arm.com
Signed-off-by: Arnaldo Carvalho de Melo

perf list: Add JSON output option

2022-11-23T13:29:59+00:00

Output events and metrics in a JSON format by overriding the print
callbacks. Currently other command line options aren't supported and
metrics are repeated once per metric group.

Committer testing:

  $ perf list cache

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

    L1-dcache-load-misses                              [Hardware cache event]
    L1-dcache-loads                                    [Hardware cache event]
    L1-dcache-prefetches                               [Hardware cache event]
    L1-icache-load-misses                              [Hardware cache event]
    L1-icache-loads                                    [Hardware cache event]
    branch-load-misses                                 [Hardware cache event]
    branch-loads                                       [Hardware cache event]
    dTLB-load-misses                                   [Hardware cache event]
    dTLB-loads                                         [Hardware cache event]
    iTLB-load-misses                                   [Hardware cache event]
    iTLB-loads                                         [Hardware cache event]
  $ perf list --json cache
  [
  {
          "Unit": "cache",
          "EventName": "L1-dcache-load-misses",
          "EventType": "Hardware cache event"
  },
  {
          "Unit": "cache",
          "EventName": "L1-dcache-loads",
          "EventType": "Hardware cache event"
  },
  {
          "Unit": "cache",
          "EventName": "L1-dcache-prefetches",
          "EventType": "Hardware cache event"
  },
  {
          "Unit": "cache",
          "EventName": "L1-icache-load-misses",
          "EventType": "Hardware cache event"
  },
  {
          "Unit": "cache",
          "EventName": "L1-icache-loads",
          "EventType": "Hardware cache event"
  },
  {
          "Unit": "cache",
          "EventName": "branch-load-misses",
          "EventType": "Hardware cache event"
  },
  {
          "Unit": "cache",
          "EventName": "branch-loads",
          "EventType": "Hardware cache event"
  },
  {
          "Unit": "cache",
          "EventName": "dTLB-load-misses",
          "EventType": "Hardware cache event"
  },
  {
          "Unit": "cache",
          "EventName": "dTLB-loads",
          "EventType": "Hardware cache event"
  },
  {
          "Unit": "cache",
          "EventName": "iTLB-load-misses",
          "EventType": "Hardware cache event"
  },
  {
          "Unit": "cache",
          "EventName": "iTLB-loads",
          "EventType": "Hardware cache event"
  }
  ]
  $

Signed-off-by: Ian Rogers 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Caleb Biggers 
Cc: Jiri Olsa 
Cc: Kajol Jain 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Perry Taylor 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Rob Herring 
Cc: Sandipan Das 
Cc: Stephane Eranian 
Cc: Weilin Wang 
Cc: Xin Gao 
Cc: Xing Zhengjun 
Link: http://lore.kernel.org/lkml/20221114210723.2749751-11-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf list: Generalize limiting to a PMU name

2022-11-15T13:25:48+00:00

Deprecate the --cputype option and add a --unit option where '--unit
cpu_atom' behaves like '--cputype atom'. The --unit option can be used
with arbitrary PMUs, for example:

```
$ perf list --unit msr pmu

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

  msr/aperf/                                         [Kernel PMU event]
  msr/cpu_thermal_margin/                            [Kernel PMU event]
  msr/mperf/                                         [Kernel PMU event]
  msr/pperf/                                         [Kernel PMU event]
  msr/smi/                                           [Kernel PMU event]
  msr/tsc/                                           [Kernel PMU event]
```

Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Caleb Biggers 
Cc: Jiri Olsa 
Cc: Kajol Jain 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Perry Taylor 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Rob Herring 
Cc: Sandipan Das 
Cc: Stephane Eranian 
Cc: Weilin Wang 
Cc: Xin Gao 
Cc: Xing Zhengjun 
Link: http://lore.kernel.org/lkml/20221114210723.2749751-6-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Make quiet mode consistent between tools

2022-10-27T19:37:26+00:00

Use the global quiet variable everywhere so that all tools hide warnings
in quiet mode and update the documentation to reflect this.

'perf probe' claimed that errors are not printed in quiet mode but I
don't see this so remove it from the docs.

Signed-off-by: James Clark 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: https://lore.kernel.org/r/20221018094137.783081-3-james.clark@arm.com
Signed-off-by: Arnaldo Carvalho de Melo

perf scripts python: intel-pt-events.py: Add ability interleave output

2022-10-27T19:37:26+00:00

Intel PT timestamps are not provided for every branch, let alone every
instruction, so there can be many samples with the same timestamp. With
per-cpu contexts, decoding is done for each CPU in turn, which can make it
difficult to see what is happening on different CPUs at the same time.
Currently the interleaving from perf script --itrace=i0ns is quite coarse
grained. There are often long stretches executing on one CPU and nothing on
another.

Some people are interested in seeing what happened on multiple CPUs before
a crash to debug races etc.

To improve perf script interleaving for parallel execution, the
intel-pt-events.py script has been enhanced to enable interleaving the
output with the same timestamp from different CPUs. It is understood that
interleaving is not perfect or causal.

Add parameter --interleave [] to interleave sample output for the same
timestamp so that no more than n samples for a CPU are displayed in a row.
'n' defaults to 4. Note this only affects the order of output, and only
when the timestamp is the same.

Example:

  $ perf script intel-pt-events.py --insn-trace --interleave 3
  ...
  bash  2267/2267  [004]  9323.692625625  563caa3c86f0  jz 0x563caa3c89c7        run_pending_traps+0x30 (/usr/bin/bash)   IPC: 1.52 (38/25)
  bash  2267/2267  [004]  9323.692625625  563caa3c89c7  movq  0x118(%rsp), %rax  run_pending_traps+0x307 (/usr/bin/bash)
  bash  2267/2267  [004]  9323.692625625  563caa3c89cf  subq  %fs:0x28, %rax     run_pending_traps+0x30f (/usr/bin/bash)
  bash  2270/2270  [007]  9323.692625625  55dc58cabf02  jz 0x55dc58cabf48        unquoted_glob_pattern_p+0x102 (/usr/bin/bash)   IPC: 1.56 (25/16)
  bash  2270/2270  [007]  9323.692625625  55dc58cabf04  cmp $0x5d, %al           unquoted_glob_pattern_p+0x104 (/usr/bin/bash)
  bash  2270/2270  [007]  9323.692625625  55dc58cabf06  jnz 0x55dc58cabf10       unquoted_glob_pattern_p+0x106 (/usr/bin/bash)
  bash  2264/2264  [001]  9323.692625625  7fd556a4376c  jbe 0x7fd556a43ac8       round_and_return+0x3fc (/usr/lib/x86_64-linux-gnu/libc.so.6)   IPC: 4.30 (43/10)
  bash  2264/2264  [001]  9323.692625625  7fd556a43772  and $0x8, %edx           round_and_return+0x402 (/usr/lib/x86_64-linux-gnu/libc.so.6)
  bash  2264/2264  [001]  9323.692625625  7fd556a43775  jnz 0x7fd556a43ac8       round_and_return+0x405 (/usr/lib/x86_64-linux-gnu/libc.so.6)
  bash  2267/2267  [004]  9323.692625625  563caa3c89d8  jnz 0x563caa3c8b11       run_pending_traps+0x318 (/usr/bin/bash)
  bash  2267/2267  [004]  9323.692625625  563caa3c89de  add $0x128, %rsp         run_pending_traps+0x31e (/usr/bin/bash)
  bash  2267/2267  [004]  9323.692625625  563caa3c89e5  popq  %rbx               run_pending_traps+0x325 (/usr/bin/bash)
  ...

Signed-off-by: Adrian Hunter 
Cc: Andi Kleen 
Cc: Ian Rogers 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: https://lore.kernel.org/r/20221020152509.5298-1-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf docs: Fix man page build wrt perf-arm-coresight.txt

2022-10-25T20:40:48+00:00

perf build assumes documentation files starting with "perf-" are man
pages but perf-arm-coresight.txt is not a man page:

  asciidoc: ERROR: perf-arm-coresight.txt: line 2: malformed manpage title
  asciidoc: ERROR: perf-arm-coresight.txt: line 3: name section expected
  asciidoc: FAILED: perf-arm-coresight.txt: line 3: section title expected
  make[3]: *** [Makefile:266: perf-arm-coresight.xml] Error 1
  make[3]: *** Waiting for unfinished jobs....
  make[2]: *** [Makefile.perf:895: man] Error 2

Fix by renaming it.

Fixes: dc2e0fb00bb2b24f ("perf test coresight: Add relevant documentation about ARM64 CoreSight testing")
Reported-by: Christian Borntraeger 
Reported-by: Sven Schnelle 
Reviewed-by: Leo Yan 
Signed-off-by: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Carsten Haitzler 
Cc: coresight@lists.linaro.org
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: Mark Rutland 
Cc: Mathieu Poirier 
Cc: Mike Leach 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Suzuki Poulouse 
Link: https://lore.kernel.org/r/a176a3e1-6ddc-bb63-e41c-15cda8c2d5d2@intel.com
Signed-off-by: Arnaldo Carvalho de Melo