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: 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.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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