From: Jin Yao yao.jin@linux.intel.com
[ Upstream commit f2013278ae40b89cc27916366c407ce5261815ef ]
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: b65a7d372b1a55db ("perf hist: Support block formats with compare/sort/display") Signed-off-by: Jin Yao yao.jin@linux.intel.com Reviewed-by: Andi 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.com Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- tools/perf/util/block-info.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/tools/perf/util/block-info.c b/tools/perf/util/block-info.c index 423ec69bda6c..5ecd4f401f32 100644 --- a/tools/perf/util/block-info.c +++ b/tools/perf/util/block-info.c @@ -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; }