From 797efbc523b37de29dc533a8561d34b97deb42e4 Mon Sep 17 00:00:00 2001 From: Adrian Hunter Date: Mon, 11 Jul 2022 12:31:55 +0300 Subject: [PATCH] perf tools: Add guest_cpu to hypervisor threads It is possible to know which guest machine was running at a point in time based on the PID of the currently running host thread. That is, perf identifies guest machines by the PID of the hypervisor. To determine the guest CPU, put it on the hypervisor (QEMU) thread for that VCPU. This is done when processing the id_index which provides the necessary information. Signed-off-by: Adrian Hunter Cc: Andi Kleen Cc: Ian Rogers Cc: Jiri Olsa Cc: Namhyung Kim Cc: kvm@vger.kernel.org Link: https://lore.kernel.org/r/20220711093218.10967-13-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/session.c | 18 ++++++++++++++++++ tools/perf/util/thread.c | 1 + tools/perf/util/thread.h | 1 + 3 files changed, 20 insertions(+) diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c index 1af981d5ad3c7..91a091c359450 100644 --- a/tools/perf/util/session.c +++ b/tools/perf/util/session.c @@ -2769,6 +2769,20 @@ static int perf_session__register_guest(struct perf_session *session, pid_t mach return 0; } +static int perf_session__set_guest_cpu(struct perf_session *session, pid_t pid, + pid_t tid, int guest_cpu) +{ + struct machine *machine = &session->machines.host; + struct thread *thread = machine__findnew_thread(machine, pid, tid); + + if (!thread) + return -ENOMEM; + thread->guest_cpu = guest_cpu; + thread__put(thread); + + return 0; +} + int perf_event__process_id_index(struct perf_session *session, union perf_event *event) { @@ -2845,6 +2859,10 @@ int perf_event__process_id_index(struct perf_session *session, last_pid = sid->machine_pid; perf_guest = true; } + + ret = perf_session__set_guest_cpu(session, sid->machine_pid, e->tid, e2->vcpu); + if (ret) + return ret; } return 0; } diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c index 665e5c0618ed3..e3e5427e1c3c8 100644 --- a/tools/perf/util/thread.c +++ b/tools/perf/util/thread.c @@ -47,6 +47,7 @@ struct thread *thread__new(pid_t pid, pid_t tid) thread->tid = tid; thread->ppid = -1; thread->cpu = -1; + thread->guest_cpu = -1; thread->lbr_stitch_enable = false; INIT_LIST_HEAD(&thread->namespaces_list); INIT_LIST_HEAD(&thread->comm_list); diff --git a/tools/perf/util/thread.h b/tools/perf/util/thread.h index b066fb30d203d..241f300d7d6ef 100644 --- a/tools/perf/util/thread.h +++ b/tools/perf/util/thread.h @@ -39,6 +39,7 @@ struct thread { pid_t tid; pid_t ppid; int cpu; + int guest_cpu; /* For QEMU thread */ refcount_t refcnt; bool comm_set; int comm_len; -- 2.30.2