Yang Jihong 19807bba5a perf kwork: Add softirq latency support
Implements softirq latency function.

Test cases:

  # perf kwork -k softirq lat

    Kwork Name                     | Cpu  | Avg delay     | Count     | Max delay     | Max delay start     | Max delay end       |
   --------------------------------------------------------------------------------------------------------------------------------
    (s)TIMER:1                     | 0006 |      1.048 ms |         1 |      1.048 ms |      44000.829759 s |      44000.830807 s |
    (s)TIMER:1                     | 0001 |      1.008 ms |         4 |      3.434 ms |      43997.662069 s |      43997.665503 s |
    (s)RCU:9                       | 0006 |      0.675 ms |         7 |      1.328 ms |      43997.670304 s |      43997.671632 s |
    (s)RCU:9                       | 0000 |      0.414 ms |       701 |      3.996 ms |      43997.661170 s |      43997.665167 s |
    (s)RCU:9                       | 0005 |      0.245 ms |        88 |      1.866 ms |      43997.683105 s |      43997.684971 s |
    (s)SCHED:7                     | 0000 |      0.158 ms |       677 |      2.639 ms |      44004.785716 s |      44004.788355 s |
    ... <SNIP> ...
    (s)RCU:9                       | 0002 |      0.141 ms |       932 |      1.662 ms |      44005.010206 s |      44005.011868 s |
    (s)RCU:9                       | 0003 |      0.129 ms |      2193 |      1.507 ms |      44006.010208 s |      44006.011715 s |
    (s)TIMER:1                     | 0005 |      0.128 ms |         1 |      0.128 ms |      44007.820346 s |      44007.820474 s |
    (s)SCHED:7                     | 0002 |      0.040 ms |      1731 |      0.211 ms |      44005.009237 s |      44005.009447 s |
   --------------------------------------------------------------------------------------------------------------------------------

  # perf kwork -k softirq lat -C 1,2

    Kwork Name                     | Cpu  | Avg delay     | Count     | Max delay     | Max delay start     | Max delay end       |
   --------------------------------------------------------------------------------------------------------------------------------
    (s)TIMER:1                     | 0001 |      1.008 ms |         4 |      3.434 ms |      43997.662069 s |      43997.665503 s |
    (s)RCU:9                       | 0001 |      0.216 ms |      1619 |      3.659 ms |      43997.662069 s |      43997.665727 s |
    (s)RCU:9                       | 0002 |      0.141 ms |       932 |      1.662 ms |      44005.010206 s |      44005.011868 s |
    (s)NET_RX:3                    | 0002 |      0.106 ms |         5 |      0.163 ms |      44005.012255 s |      44005.012418 s |
    (s)TIMER:1                     | 0002 |      0.084 ms |         9 |      0.114 ms |      44005.009168 s |      44005.009282 s |
    (s)SCHED:7                     | 0001 |      0.049 ms |       655 |      0.837 ms |      44005.707998 s |      44005.708835 s |
    (s)SCHED:7                     | 0002 |      0.040 ms |      1731 |      0.211 ms |      44005.009237 s |      44005.009447 s |
   --------------------------------------------------------------------------------------------------------------------------------

  # perf kwork -k softirq lat -n RCU

    Kwork Name                     | Cpu  | Avg delay     | Count     | Max delay     | Max delay start     | Max delay end       |
   --------------------------------------------------------------------------------------------------------------------------------
    (s)RCU:9                       | 0006 |      0.675 ms |         7 |      1.328 ms |      43997.670304 s |      43997.671632 s |
    (s)RCU:9                       | 0000 |      0.414 ms |       701 |      3.996 ms |      43997.661170 s |      43997.665167 s |
    (s)RCU:9                       | 0005 |      0.245 ms |        88 |      1.866 ms |      43997.683105 s |      43997.684971 s |
    (s)RCU:9                       | 0004 |      0.237 ms |        26 |      0.792 ms |      43997.683018 s |      43997.683810 s |
    (s)RCU:9                       | 0007 |      0.217 ms |       140 |      1.335 ms |      43997.671080 s |      43997.672415 s |
    (s)RCU:9                       | 0001 |      0.216 ms |      1619 |      3.659 ms |      43997.662069 s |      43997.665727 s |
    (s)RCU:9                       | 0002 |      0.141 ms |       932 |      1.662 ms |      44005.010206 s |      44005.011868 s |
    (s)RCU:9                       | 0003 |      0.129 ms |      2193 |      1.507 ms |      44006.010208 s |      44006.011715 s |
   --------------------------------------------------------------------------------------------------------------------------------

  # perf kwork -k softirq lat -s count,avg -n RCU

    Kwork Name                     | Cpu  | Avg delay     | Count     | Max delay     | Max delay start     | Max delay end       |
   --------------------------------------------------------------------------------------------------------------------------------
    (s)RCU:9                       | 0003 |      0.129 ms |      2193 |      1.507 ms |      44006.010208 s |      44006.011715 s |
    (s)RCU:9                       | 0001 |      0.216 ms |      1619 |      3.659 ms |      43997.662069 s |      43997.665727 s |
    (s)RCU:9                       | 0002 |      0.141 ms |       932 |      1.662 ms |      44005.010206 s |      44005.011868 s |
    (s)RCU:9                       | 0000 |      0.414 ms |       701 |      3.996 ms |      43997.661170 s |      43997.665167 s |
    (s)RCU:9                       | 0007 |      0.217 ms |       140 |      1.335 ms |      43997.671080 s |      43997.672415 s |
    (s)RCU:9                       | 0005 |      0.245 ms |        88 |      1.866 ms |      43997.683105 s |      43997.684971 s |
    (s)RCU:9                       | 0004 |      0.237 ms |        26 |      0.792 ms |      43997.683018 s |      43997.683810 s |
    (s)RCU:9                       | 0006 |      0.675 ms |         7 |      1.328 ms |      43997.670304 s |      43997.671632 s |
   --------------------------------------------------------------------------------------------------------------------------------

  # perf kwork -k softirq lat --time 43997,

    Kwork Name                     | Cpu  | Avg delay     | Count     | Max delay     | Max delay start     | Max delay end       |
   --------------------------------------------------------------------------------------------------------------------------------
    (s)TIMER:1                     | 0006 |      1.048 ms |         1 |      1.048 ms |      44000.829759 s |      44000.830807 s |
    (s)TIMER:1                     | 0001 |      1.008 ms |         4 |      3.434 ms |      43997.662069 s |      43997.665503 s |
    (s)RCU:9                       | 0006 |      0.675 ms |         7 |      1.328 ms |      43997.670304 s |      43997.671632 s |
    (s)RCU:9                       | 0000 |      0.414 ms |       701 |      3.996 ms |      43997.661170 s |      43997.665167 s |
    (s)TIMER:1                     | 0004 |      0.083 ms |        21 |      0.127 ms |      44004.969171 s |      44004.969298 s |
    ... <SNIP> ...
    (s)SCHED:7                     | 0005 |      0.050 ms |         4 |      0.086 ms |      43997.684852 s |      43997.684938 s |
    (s)SCHED:7                     | 0001 |      0.049 ms |       655 |      0.837 ms |      44005.707998 s |      44005.708835 s |
    (s)SCHED:7                     | 0007 |      0.044 ms |       171 |      0.077 ms |      43997.943265 s |      43997.943342 s |
    (s)SCHED:7                     | 0002 |      0.040 ms |      1731 |      0.211 ms |      44005.009237 s |      44005.009447 s |
   --------------------------------------------------------------------------------------------------------------------------------

Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220709015033.38326-12-yangjihong1@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-07-26 16:31:54 -03:00
2022-07-17 13:30:22 -07:00

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