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linux/tools/perf/util/intel-tpebs.h

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perf stat: Fork and launch 'perf record' when 'perf stat' needs to get retire latency value for a metric. When retire_latency value is used in a metric formula, evsel would fork a 'perf record' process with "-e" and "-W" options. 'perf record' will collect required retire_latency values in parallel while 'perf stat' is collecting counting values. At the point of time that 'perf stat' stops counting, evsel would stop 'perf record' by sending sigterm signal to 'perf record' process. Sampled data will be processed to get retire latency value. Another thread is required to synchronize between 'perf stat' and 'perf record' when we pass data through pipe. Retire_latency evsel is not opened for 'perf stat' so that there is no counter wasted on it. This commit includes code suggested by Namhyung to adjust reading size for groups that include retire_latency evsels. In current :R parsing implementation, the parser would recognize events with retire_latency modifier and insert them into the evlist like a normal event. Ideally, we need to avoid counting these events. In this commit, at the time when a retire_latency evsel is read, set the retire latency value processed from the sampled data to count value. This sampled retire latency value will be used for metric calculation and final event count print out. No special metric calculation and event print out code required for retire_latency events. Reviewed-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Weilin Wang <weilin.wang@intel.com> Acked-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Caleb Biggers <caleb.biggers@intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Perry Taylor <perry.taylor@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Samantha Alt <samantha.alt@intel.com> Link: https://lore.kernel.org/r/20240720062102.444578-4-weilin.wang@intel.com [ Squashed the 3rd and 4th commit in the series to keep it building patch by patch ] [ Constified the 'struct perf_tool' pointer in process_sample_event() ] [ Use perf_tool__init(&tool, false) to address a segfault I reported and Ian/Weilin diagnosed ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2024-07-19 23:20:56 -07:00
/* SPDX-License-Identifier: GPL-2.0-only */
/*
* intel_tpebs.h: Intel TEPBS support
*/
#ifndef INCLUDE__PERF_INTEL_TPEBS_H__
#define INCLUDE__PERF_INTEL_TPEBS_H__
#include "stat.h"
#include "evsel.h"
#ifdef HAVE_ARCH_X86_64_SUPPORT
extern bool tpebs_recording;
int tpebs_start(struct evlist *evsel_list);
void tpebs_delete(void);
int tpebs_set_evsel(struct evsel *evsel, int cpu_map_idx, int thread);
#else
static inline int tpebs_start(struct evlist *evsel_list __maybe_unused)
{
return 0;
}
static inline void tpebs_delete(void) {};
static inline int tpebs_set_evsel(struct evsel *evsel __maybe_unused,
int cpu_map_idx __maybe_unused,
int thread __maybe_unused)
{
return 0;
}
#endif
#endif
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