Commit f2013278 authored by Jin Yao's avatar Jin Yao Committed by Arnaldo Carvalho de Melo

perf report: Fix wrong LBR block sorting

When '--total-cycles' is specified, it supports sorting for all blocks
by 'Sampled Cycles%'. This is useful to concentrate on the globally
hottest blocks.

'Sampled Cycles%' - block sampled cycles aggregation / total sampled cycles

But in current code, it doesn't use the cycles aggregation. Part of
'cycles' counting is possibly dropped for some overlap jumps. But for
identifying the hot block, we always need the full cycles.

  # perf record -b ./triad_loop
  # perf report --total-cycles --stdio

Before:

  #
  # Sampled Cycles%  Sampled Cycles  Avg Cycles%  Avg Cycles                                          [Program Block Range]      Shared Object
  # ...............  ..............  ...........  ..........  .............................................................  .................
  #
              0.81%             793        4.32%         793                           [setup-vdso.h:34 -> setup-vdso.h:40]         ld-2.27.so
              0.49%             480        0.87%         160                    [native_write_msr+0 -> native_write_msr+16]  [kernel.kallsyms]
              0.48%             476        0.52%          95                      [native_read_msr+0 -> native_read_msr+29]  [kernel.kallsyms]
              0.31%             303        1.65%         303                              [nmi_restore+0 -> nmi_restore+37]  [kernel.kallsyms]
              0.26%             255        1.39%         255      [nohz_balance_exit_idle+75 -> nohz_balance_exit_idle+162]  [kernel.kallsyms]
              0.24%             234        1.28%         234                       [end_repeat_nmi+67 -> end_repeat_nmi+83]  [kernel.kallsyms]
              0.23%             227        1.24%         227            [__irqentry_text_end+96 -> __irqentry_text_end+126]  [kernel.kallsyms]
              0.20%             194        1.06%         194             [native_set_debugreg+52 -> native_set_debugreg+56]  [kernel.kallsyms]
              0.11%             106        0.14%          26                [native_sched_clock+0 -> native_sched_clock+98]  [kernel.kallsyms]
              0.10%              97        0.53%          97            [trigger_load_balance+0 -> trigger_load_balance+67]  [kernel.kallsyms]
              0.09%              85        0.46%          85             [get-dynamic-info.h:102 -> get-dynamic-info.h:111]         ld-2.27.so
  ...
              0.00%           92.7K        0.02%           4                           [triad_loop.c:64 -> triad_loop.c:65]         triad_loop

The hottest block '[triad_loop.c:64 -> triad_loop.c:65]' is not at
the top of output.

After:

  # Sampled Cycles%  Sampled Cycles  Avg Cycles%  Avg Cycles                                           [Program Block Range]      Shared Object
  # ...............  ..............  ...........  ..........  ..............................................................  .................
  #
             94.35%           92.7K        0.02%           4                            [triad_loop.c:64 -> triad_loop.c:65]         triad_loop
              0.81%             793        4.32%         793                            [setup-vdso.h:34 -> setup-vdso.h:40]         ld-2.27.so
              0.49%             480        0.87%         160                     [native_write_msr+0 -> native_write_msr+16]  [kernel.kallsyms]
              0.48%             476        0.52%          95                       [native_read_msr+0 -> native_read_msr+29]  [kernel.kallsyms]
              0.31%             303        1.65%         303                               [nmi_restore+0 -> nmi_restore+37]  [kernel.kallsyms]
              0.26%             255        1.39%         255       [nohz_balance_exit_idle+75 -> nohz_balance_exit_idle+162]  [kernel.kallsyms]
              0.24%             234        1.28%         234                        [end_repeat_nmi+67 -> end_repeat_nmi+83]  [kernel.kallsyms]
              0.23%             227        1.24%         227             [__irqentry_text_end+96 -> __irqentry_text_end+126]  [kernel.kallsyms]
              0.20%             194        1.06%         194              [native_set_debugreg+52 -> native_set_debugreg+56]  [kernel.kallsyms]
              0.11%             106        0.14%          26                 [native_sched_clock+0 -> native_sched_clock+98]  [kernel.kallsyms]
              0.10%              97        0.53%          97             [trigger_load_balance+0 -> trigger_load_balance+67]  [kernel.kallsyms]
              0.09%              85        0.46%          85              [get-dynamic-info.h:102 -> get-dynamic-info.h:111]         ld-2.27.so
              0.08%              82        0.06%          11  [intel_pmu_drain_pebs_nhm+580 -> intel_pmu_drain_pebs_nhm+627]  [kernel.kallsyms]
              0.08%              77        0.42%          77                  [lru_add_drain_cpu+0 -> lru_add_drain_cpu+133]  [kernel.kallsyms]
              0.08%              74        0.10%          18                [handle_pmi_common+271 -> handle_pmi_common+310]  [kernel.kallsyms]
              0.08%              74        0.40%          74              [get-dynamic-info.h:131 -> get-dynamic-info.h:157]         ld-2.27.so
              0.07%              69        0.09%          17  [intel_pmu_drain_pebs_nhm+432 -> intel_pmu_drain_pebs_nhm+468]  [kernel.kallsyms]

Now the hottest block is reported at the top of output.

Fixes: b65a7d37 ("perf hist: Support block formats with compare/sort/display")
Signed-off-by: default avatarJin Yao <yao.jin@linux.intel.com>
Reviewed-by: default avatarAndi Kleen <ak@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210407024452.29988-1-yao.jin@linux.intel.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 026334a3
......@@ -201,7 +201,7 @@ static int block_total_cycles_pct_entry(struct perf_hpp_fmt *fmt,
double ratio = 0.0;
if (block_fmt->total_cycles)
ratio = (double)bi->cycles / (double)block_fmt->total_cycles;
ratio = (double)bi->cycles_aggr / (double)block_fmt->total_cycles;
return color_pct(hpp, block_fmt->width, 100.0 * ratio);
}
......@@ -216,9 +216,9 @@ static int64_t block_total_cycles_pct_sort(struct perf_hpp_fmt *fmt,
double l, r;
if (block_fmt->total_cycles) {
l = ((double)bi_l->cycles /
l = ((double)bi_l->cycles_aggr /
(double)block_fmt->total_cycles) * 100000.0;
r = ((double)bi_r->cycles /
r = ((double)bi_r->cycles_aggr /
(double)block_fmt->total_cycles) * 100000.0;
return (int64_t)l - (int64_t)r;
}
......
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