Commit 0bb82cf5 authored by Adrian Hunter's avatar Adrian Hunter Committed by Arnaldo Carvalho de Melo
Browse files

perf intel-pt: Track guest context switches 



Use guest context switch events to keep track of which guest thread is
running on a particular guest machine and VCPU.

Signed-off-by: default avatarAdrian Hunter <adrian.hunter@intel.com>
Acked-by: default avatarIan Rogers <irogers@google.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: kvm@vger.kernel.org
Link: https://lore.kernel.org/r/20220711093218.10967-31-adrian.hunter@intel.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 12374a16

tools/perf/util/intel-pt.c

+23 −0
Original line number Diff line number Diff line
@@ -78,6 +78,7 @@ struct intel_pt { 
	bool use_thread_stack;

	bool callstack;

	bool cap_event_trace;

	bool have_guest_sideband;

	unsigned int br_stack_sz;

	unsigned int br_stack_sz_plus;

	int have_sched_switch;
@@ -3079,6 +3080,25 @@ static int intel_pt_context_switch_in(struct intel_pt *pt, 
	return machine__set_current_tid(pt->machine, cpu, pid, tid);

}



static int intel_pt_guest_context_switch(struct intel_pt *pt,

					 union perf_event *event,

					 struct perf_sample *sample)

{

	bool out = event->header.misc & PERF_RECORD_MISC_SWITCH_OUT;

	struct machines *machines = &pt->session->machines;

	struct machine *machine = machines__find(machines, sample->machine_pid);



	pt->have_guest_sideband = true;



	if (out)

		return 0;



	if (!machine)

		return -EINVAL;



	return machine__set_current_tid(machine, sample->vcpu, sample->pid, sample->tid);

}



static int intel_pt_context_switch(struct intel_pt *pt, union perf_event *event,

				   struct perf_sample *sample)

{
@@ -3086,6 +3106,9 @@ static int intel_pt_context_switch(struct intel_pt *pt, union perf_event *event, 
	pid_t pid, tid;

	int cpu, ret;



	if (perf_event__is_guest(event))

		return intel_pt_guest_context_switch(pt, event, sample);



	cpu = sample->cpu;



	if (pt->have_sched_switch == 3) {