diff options
Diffstat (limited to 'tools/perf/util')
-rw-r--r-- | tools/perf/util/synthetic-events.c | 8 | ||||
-rw-r--r-- | tools/perf/util/tsc.c | 71 |
2 files changed, 71 insertions, 8 deletions
diff --git a/tools/perf/util/synthetic-events.c b/tools/perf/util/synthetic-events.c index 89b390623b63..3ca5d9399680 100644 --- a/tools/perf/util/synthetic-events.c +++ b/tools/perf/util/synthetic-events.c @@ -2006,14 +2006,6 @@ int perf_event__synthesize_stat_events(struct perf_stat_config *config, struct p return 0; } -int __weak perf_event__synth_time_conv(const struct perf_event_mmap_page *pc __maybe_unused, - struct perf_tool *tool __maybe_unused, - perf_event__handler_t process __maybe_unused, - struct machine *machine __maybe_unused) -{ - return 0; -} - extern const struct perf_header_feature_ops feat_ops[HEADER_LAST_FEATURE]; int perf_event__synthesize_features(struct perf_tool *tool, struct perf_session *session, diff --git a/tools/perf/util/tsc.c b/tools/perf/util/tsc.c index bfa782421cbd..9e3f04ddddf8 100644 --- a/tools/perf/util/tsc.c +++ b/tools/perf/util/tsc.c @@ -1,7 +1,16 @@ // SPDX-License-Identifier: GPL-2.0 +#include <errno.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) @@ -25,6 +34,68 @@ u64 tsc_to_perf_time(u64 cyc, struct perf_tsc_conversion *tc) ((rem * tc->time_mult) >> tc->time_shift); } +int perf_read_tsc_conversion(const struct perf_event_mmap_page *pc, + struct perf_tsc_conversion *tc) +{ + bool cap_user_time_zero; + 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; + cap_user_time_zero = pc->cap_user_time_zero; + 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 (!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; + + return process(tool, &event, NULL, machine); +} + u64 __weak rdtsc(void) { return 0; |