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perf tsc: Support cap_user_time_short for event TIME_CONV

The synthesized event TIME_CONV doesn't contain the complete parameters
for counters, this will lead to wrong conversion between counter cycles
and timestamp.

This patch extends event TIME_CONV to record flags 'cap_user_time_zero'
which is used to indicate the counter parameters are valid or not, if
not will directly return 0 for timestamp calculation. And record the
flag 'cap_user_time_short' and its relevant fields 'time_cycles' and
'time_mask' for cycle calibration.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Kemeng Shi <shikemeng@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nick Gasson <nick.gasson@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Remi Bernon <rbernon@codeweavers.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Steve Maclean <steve.maclean@microsoft.com>
Cc: Will Deacon <will@kernel.org>
Cc: Zou Wei <zou_wei@huawei.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lore.kernel.org/lkml/20200914115311.2201-5-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

authored by

Leo Yan and committed by
Arnaldo Carvalho de Melo d110162c 78a93d4c

+16 -4
+4
tools/lib/perf/include/perf/event.h
··· 324 324 __u64 time_shift; 325 325 __u64 time_mult; 326 326 __u64 time_zero; 327 + __u64 time_cycles; 328 + __u64 time_mask; 329 + bool cap_user_time_zero; 330 + bool cap_user_time_short; 327 331 }; 328 332 329 333 struct perf_record_header_feature {
+8 -4
tools/perf/util/jitdump.c
··· 374 374 if (!jd->use_arch_timestamp) 375 375 return timestamp; 376 376 377 - tc.time_shift = jd->session->time_conv.time_shift; 378 - tc.time_mult = jd->session->time_conv.time_mult; 379 - tc.time_zero = jd->session->time_conv.time_zero; 377 + tc.time_shift = jd->session->time_conv.time_shift; 378 + tc.time_mult = jd->session->time_conv.time_mult; 379 + tc.time_zero = jd->session->time_conv.time_zero; 380 + tc.time_cycles = jd->session->time_conv.time_cycles; 381 + tc.time_mask = jd->session->time_conv.time_mask; 382 + tc.cap_user_time_zero = jd->session->time_conv.cap_user_time_zero; 383 + tc.cap_user_time_short = jd->session->time_conv.cap_user_time_short; 380 384 381 - if (!tc.time_mult) 385 + if (!tc.cap_user_time_zero) 382 386 return 0; 383 387 384 388 return tsc_to_perf_time(timestamp, &tc);
+4
tools/perf/util/tsc.c
··· 98 98 event.time_conv.time_mult = tc.time_mult; 99 99 event.time_conv.time_shift = tc.time_shift; 100 100 event.time_conv.time_zero = tc.time_zero; 101 + event.time_conv.time_cycles = tc.time_cycles; 102 + event.time_conv.time_mask = tc.time_mask; 103 + event.time_conv.cap_user_time_zero = tc.cap_user_time_zero; 104 + event.time_conv.cap_user_time_short = tc.cap_user_time_short; 101 105 102 106 return process(tool, &event, NULL, machine); 103 107 }