Hi, This patch prototypes exposing the type of context-switch-out event using PERF_RECORD_MISC_EXT_RESERVED bit for PERF_RECORD_SWITCH[_CPU_WIDE] records.
Types of context-switch-out events introduced by the patch meant to be a) preempted (task->state == TASK_RUNNING) or b) yielded == !preempted; The changes have been manually tested on Fedora 27 with the patched kernel: git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git perf/core Signed-off-by: Alexey Budankov <alexey.budan...@linux.intel.com> --- kernel/events/core.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index 57898102847f..e3ca597f4e2b 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -7216,6 +7216,8 @@ static void perf_event_switch(struct task_struct *task, struct task_struct *next_prev, bool sched_in) { struct perf_switch_event switch_event; + __u16 switch_type = sched_in ? 0 : PERF_RECORD_MISC_SWITCH_OUT | + (task->state == TASK_RUNNING ? 0 : PERF_RECORD_MISC_EXT_RESERVED); /* N.B. caller checks nr_switch_events != 0 */ @@ -7225,7 +7227,7 @@ static void perf_event_switch(struct task_struct *task, .event_id = { .header = { /* .type */ - .misc = sched_in ? 0 : PERF_RECORD_MISC_SWITCH_OUT, + .misc = switch_type, /* .size */ }, /* .next_prev_pid */