diff options
| -rw-r--r-- | include/linux/perf_counter.h | 8 | ||||
| -rw-r--r-- | kernel/perf_counter.c | 40 |
2 files changed, 47 insertions, 1 deletions
diff --git a/include/linux/perf_counter.h b/include/linux/perf_counter.h index c8c1dfc22c9..f612941ef46 100644 --- a/include/linux/perf_counter.h +++ b/include/linux/perf_counter.h @@ -258,6 +258,14 @@ enum perf_event_type { PERF_EVENT_COMM = 3, /* + * struct { + * struct perf_event_header header; + * u64 irq_period; + * }; + */ + PERF_EVENT_PERIOD = 4, + + /* * When header.misc & PERF_EVENT_MISC_OVERFLOW the event_type field * will be PERF_RECORD_* * diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index 64113e6d194..db02eb16c77 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -1046,7 +1046,9 @@ int perf_counter_task_enable(void) return 0; } -void perf_adjust_freq(struct perf_counter_context *ctx) +static void perf_log_period(struct perf_counter *counter, u64 period); + +static void perf_adjust_freq(struct perf_counter_context *ctx) { struct perf_counter *counter; u64 irq_period; @@ -1072,6 +1074,8 @@ void perf_adjust_freq(struct perf_counter_context *ctx) if (!irq_period) irq_period = 1; + perf_log_period(counter, irq_period); + counter->hw.irq_period = irq_period; counter->hw.interrupts = 0; } @@ -2407,6 +2411,40 @@ void perf_counter_munmap(unsigned long addr, unsigned long len, } /* + * + */ + +static void perf_log_period(struct perf_counter *counter, u64 period) +{ + struct perf_output_handle handle; + int ret; + + struct { + struct perf_event_header header; + u64 time; + u64 period; + } freq_event = { + .header = { + .type = PERF_EVENT_PERIOD, + .misc = 0, + .size = sizeof(freq_event), + }, + .time = sched_clock(), + .period = period, + }; + + if (counter->hw.irq_period == period) + return; + + ret = perf_output_begin(&handle, counter, sizeof(freq_event), 0, 0); + if (ret) + return; + + perf_output_put(&handle, freq_event); + perf_output_end(&handle); +} + +/* * Generic counter overflow handling. */ |