Commit 71658de4 authored by Adrian Hunter's avatar Adrian Hunter Committed by Arnaldo Carvalho de Melo
Browse files

perf intel-pt: Determine guest thread from guest sideband 



Prior to decoding, determine what guest thread, if any, is running.

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/20220711093218.10967-33-adrian.hunter@intel.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 7d1f65b5

tools/perf/util/intel-pt.c

+67 −2
Original line number Diff line number Diff line
@@ -196,6 +196,10 @@ struct intel_pt_queue { 
	struct machine *guest_machine;

	struct thread *guest_thread;

	struct thread *unknown_guest_thread;

	pid_t guest_machine_pid;

	pid_t guest_pid;

	pid_t guest_tid;

	int vcpu;

	bool exclude_kernel;

	bool have_sample;

	u64 time;
@@ -759,7 +763,12 @@ static int intel_pt_walk_next_insn(struct intel_pt_insn *intel_pt_insn, 
	cpumode = intel_pt_nr_cpumode(ptq, *ip, nr);



	if (nr) {

		if ((!symbol_conf.guest_code && cpumode != PERF_RECORD_MISC_GUEST_KERNEL) ||

		if (ptq->pt->have_guest_sideband) {

			if (!ptq->guest_machine || ptq->guest_machine_pid != ptq->pid) {

				intel_pt_log("ERROR: guest sideband but no guest machine\n");

				return -EINVAL;

			}

		} else if ((!symbol_conf.guest_code && cpumode != PERF_RECORD_MISC_GUEST_KERNEL) ||

			   intel_pt_get_guest(ptq)) {

			intel_pt_log("ERROR: no guest machine\n");

			return -EINVAL;
@@ -1385,6 +1394,55 @@ static void intel_pt_first_timestamp(struct intel_pt *pt, u64 timestamp) 
	}

}



static int intel_pt_get_guest_from_sideband(struct intel_pt_queue *ptq)

{

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

	struct machine *machine;

	pid_t machine_pid = ptq->pid;

	pid_t tid;

	int vcpu;



	if (machine_pid <= 0)

		return 0; /* Not a guest machine */



	machine = machines__find(machines, machine_pid);

	if (!machine)

		return 0; /* Not a guest machine */



	if (ptq->guest_machine != machine) {

		ptq->guest_machine = NULL;

		thread__zput(ptq->guest_thread);

		thread__zput(ptq->unknown_guest_thread);



		ptq->unknown_guest_thread = machine__find_thread(machine, 0, 0);

		if (!ptq->unknown_guest_thread)

			return -1;

		ptq->guest_machine = machine;

	}



	vcpu = ptq->thread ? ptq->thread->guest_cpu : -1;

	if (vcpu < 0)

		return -1;



	tid = machine__get_current_tid(machine, vcpu);



	if (ptq->guest_thread && ptq->guest_thread->tid != tid)

		thread__zput(ptq->guest_thread);



	if (!ptq->guest_thread) {

		ptq->guest_thread = machine__find_thread(machine, -1, tid);

		if (!ptq->guest_thread)

			return -1;

	}



	ptq->guest_machine_pid = machine_pid;

	ptq->guest_pid = ptq->guest_thread->pid_;

	ptq->guest_tid = tid;

	ptq->vcpu = vcpu;



	return 0;

}



static void intel_pt_set_pid_tid_cpu(struct intel_pt *pt,

				     struct auxtrace_queue *queue)

{
@@ -1405,6 +1463,13 @@ static void intel_pt_set_pid_tid_cpu(struct intel_pt *pt, 
		if (queue->cpu == -1)

			ptq->cpu = ptq->thread->cpu;

	}



	if (pt->have_guest_sideband && intel_pt_get_guest_from_sideband(ptq)) {

		ptq->guest_machine_pid = 0;

		ptq->guest_pid = -1;

		ptq->guest_tid = -1;

		ptq->vcpu = -1;

	}

}



static void intel_pt_sample_flags(struct intel_pt_queue *ptq)