perf tools: Optimize sample parsing for ordered events
Currently when using ordered events we parse the sample twice (the perf_evlist__parse_sample function). Once before we queue the sample for sorting: perf_session__process_event perf_evlist__parse_sample(sample) perf_session__queue_event(sample.time) And then when we deliver the sorted sample: ordered_events__deliver_event perf_evlist__parse_sample perf_session__deliver_event We can skip the initial full sample parsing by using perf_evlist__parse_sample_timestamp function, which got introduced earlier. The new path looks like: perf_session__process_event perf_evlist__parse_sample_timestamp perf_session__queue_event ordered_events__deliver_event perf_session__deliver_event perf_evlist__parse_sample It saves some instructions and is slightly faster: Before: Performance counter stats for './perf.old report --stdio' (5 runs): 64,396,007,225 cycles:u ( +- 0.97% ) 105,882,112,735 instructions:u # 1.64 insn per cycle ( +- 0.00% ) 21.618103465 seconds time elapsed ( +- 1.12% ) After: Performance counter stats for './perf report --stdio' (5 runs): 60,567,807,182 cycles:u ( +- 0.40% ) 104,853,333,514 instructions:u # 1.73 insn per cycle ( +- 0.00% ) 20.168895243 seconds time elapsed ( +- 0.32% ) Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-cjp2tuk0qkjs9dxzlpmm34ua@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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