linux/tools/perf/util/tsc.c
Leo Yan 81e70d7ee4 perf session: Dump PERF_RECORD_TIME_CONV event
Now perf tool uses the common stub function process_event_op2_stub() for
dumping TIME_CONV event, thus it doesn't output the clock parameters
contained in the event.

This patch adds the callback function for dumping the hardware clock
parameters in TIME_CONV event.

Before:

  # perf report -D

  0x978 [0x38]: event: 79
  .
  . ... raw event: size 56 bytes
  .  0000:  4f 00 00 00 00 00 38 00 15 00 00 00 00 00 00 00  O.....8.........
  .  0010:  00 00 40 01 00 00 00 00 86 89 0b bf df ff ff ff  ..@........<BF><DF><FF><FF><FF>
  .  0020:  d1 c1 b2 39 03 00 00 00 ff ff ff ff ff ff ff 00  <D1><C1><B2>9....<FF><FF><FF><FF><FF><FF><FF>.
  .  0030:  01 01 00 00 00 00 00 00                          ........

  0 0 0x978 [0x38]: PERF_RECORD_TIME_CONV
  : unhandled!

  [...]

After:

  # perf report -D

  0x978 [0x38]: event: 79
  .
  . ... raw event: size 56 bytes
  .  0000:  4f 00 00 00 00 00 38 00 15 00 00 00 00 00 00 00  O.....8.........
  .  0010:  00 00 40 01 00 00 00 00 86 89 0b bf df ff ff ff  ..@........<BF><DF><FF><FF><FF>
  .  0020:  d1 c1 b2 39 03 00 00 00 ff ff ff ff ff ff ff 00  <D1><C1><B2>9....<FF><FF><FF><FF><FF><FF><FF>.
  .  0030:  01 01 00 00 00 00 00 00                          ........

  0 0 0x978 [0x38]: PERF_RECORD_TIME_CONV
  ... Time Shift      21
  ... Time Muliplier  20971520
  ... Time Zero       18446743935180835206
  ... Time Cycles     13852918225
  ... Time Mask       0xffffffffffffff
  ... Cap Time Zero   1
  ... Cap Time Short  1
  : unhandled!

  [...]

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steve MacLean <Steve.MacLean@Microsoft.com>
Cc: Yonatan Goldschmidt <yonatan.goldschmidt@granulate.io>
Link: https://lore.kernel.org/r/20210428120915.7123-5-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-04-29 10:31:00 -03:00

143 lines
3.5 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <errno.h>
#include <inttypes.h>
#include <string.h>
#include <linux/compiler.h>
#include <linux/perf_event.h>
#include <linux/stddef.h>
#include <linux/types.h>
#include <asm/barrier.h>
#include "event.h"
#include "synthetic-events.h"
#include "debug.h"
#include "tsc.h"
u64 perf_time_to_tsc(u64 ns, struct perf_tsc_conversion *tc)
{
u64 t, quot, rem;
t = ns - tc->time_zero;
quot = t / tc->time_mult;
rem = t % tc->time_mult;
return (quot << tc->time_shift) +
(rem << tc->time_shift) / tc->time_mult;
}
u64 tsc_to_perf_time(u64 cyc, struct perf_tsc_conversion *tc)
{
u64 quot, rem;
if (tc->cap_user_time_short)
cyc = tc->time_cycles +
((cyc - tc->time_cycles) & tc->time_mask);
quot = cyc >> tc->time_shift;
rem = cyc & (((u64)1 << tc->time_shift) - 1);
return tc->time_zero + quot * tc->time_mult +
((rem * tc->time_mult) >> tc->time_shift);
}
int perf_read_tsc_conversion(const struct perf_event_mmap_page *pc,
struct perf_tsc_conversion *tc)
{
u32 seq;
int i = 0;
while (1) {
seq = pc->lock;
rmb();
tc->time_mult = pc->time_mult;
tc->time_shift = pc->time_shift;
tc->time_zero = pc->time_zero;
tc->time_cycles = pc->time_cycles;
tc->time_mask = pc->time_mask;
tc->cap_user_time_zero = pc->cap_user_time_zero;
tc->cap_user_time_short = pc->cap_user_time_short;
rmb();
if (pc->lock == seq && !(seq & 1))
break;
if (++i > 10000) {
pr_debug("failed to get perf_event_mmap_page lock\n");
return -EINVAL;
}
}
if (!tc->cap_user_time_zero)
return -EOPNOTSUPP;
return 0;
}
int perf_event__synth_time_conv(const struct perf_event_mmap_page *pc,
struct perf_tool *tool,
perf_event__handler_t process,
struct machine *machine)
{
union perf_event event = {
.time_conv = {
.header = {
.type = PERF_RECORD_TIME_CONV,
.size = sizeof(struct perf_record_time_conv),
},
},
};
struct perf_tsc_conversion tc;
int err;
if (!pc)
return 0;
err = perf_read_tsc_conversion(pc, &tc);
if (err == -EOPNOTSUPP)
return 0;
if (err)
return err;
pr_debug2("Synthesizing TSC conversion information\n");
event.time_conv.time_mult = tc.time_mult;
event.time_conv.time_shift = tc.time_shift;
event.time_conv.time_zero = tc.time_zero;
event.time_conv.time_cycles = tc.time_cycles;
event.time_conv.time_mask = tc.time_mask;
event.time_conv.cap_user_time_zero = tc.cap_user_time_zero;
event.time_conv.cap_user_time_short = tc.cap_user_time_short;
return process(tool, &event, NULL, machine);
}
u64 __weak rdtsc(void)
{
return 0;
}
size_t perf_event__fprintf_time_conv(union perf_event *event, FILE *fp)
{
struct perf_record_time_conv *tc = (struct perf_record_time_conv *)event;
size_t ret;
ret = fprintf(fp, "\n... Time Shift %" PRI_lu64 "\n", tc->time_shift);
ret += fprintf(fp, "... Time Muliplier %" PRI_lu64 "\n", tc->time_mult);
ret += fprintf(fp, "... Time Zero %" PRI_lu64 "\n", tc->time_zero);
/*
* The event TIME_CONV was extended for the fields from "time_cycles"
* when supported cap_user_time_short, for backward compatibility,
* prints the extended fields only if they are contained in the event.
*/
if (event_contains(*tc, time_cycles)) {
ret += fprintf(fp, "... Time Cycles %" PRI_lu64 "\n",
tc->time_cycles);
ret += fprintf(fp, "... Time Mask %#" PRI_lx64 "\n",
tc->time_mask);
ret += fprintf(fp, "... Cap Time Zero %" PRId32 "\n",
tc->cap_user_time_zero);
ret += fprintf(fp, "... Cap Time Short %" PRId32 "\n",
tc->cap_user_time_short);
}
return ret;
}