2 files changed, 25 insertions, 14 deletions

diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index 4514e7e9b659..574feb7003ab 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -1031,11 +1031,27 @@ out_problem:
         return 0;
 }
 
+static void machine__remove_thread(struct machine *machine, struct thread *th)
+{
+        machine->last_match = NULL;
+        rb_erase(&th->rb_node, &machine->threads);
+        /*
+         * We may have references to this thread, for instance in some hist_entry
+         * instances, so just move them to a separate list.
+         */
+        list_add_tail(&th->node, &machine->dead_threads);
+}
+
 int machine__process_fork_event(struct machine *machine, union perf_event *event)
 {
-        struct thread *thread = machine__findnew_thread(machine, event->fork.tid);
+        struct thread *thread = machine__find_thread(machine, event->fork.tid);
         struct thread *parent = machine__findnew_thread(machine, event->fork.ptid);
 
+        /* if a thread currently exists for the thread id remove it */
+        if (thread != NULL)
+                machine__remove_thread(machine, thread);
+
+        thread = machine__findnew_thread(machine, event->fork.tid);
         if (dump_trace)
                 perf_event__fprintf_task(event, stdout);
 
@@ -1048,18 +1064,8 @@ int machine__process_fork_event(struct machine *machine, union perf_event *event
         return 0;
 }
 
-static void machine__remove_thread(struct machine *machine, struct thread *th)
-{
-        machine->last_match = NULL;
-        rb_erase(&th->rb_node, &machine->threads);
-        /*
-         * We may have references to this thread, for instance in some hist_entry
-         * instances, so just move them to a separate list.
-         */
-        list_add_tail(&th->node, &machine->dead_threads);
-}
-
-int machine__process_exit_event(struct machine *machine, union perf_event *event)
+int machine__process_exit_event(struct machine *machine __maybe_unused,
+                                union perf_event *event)
 {
         struct thread *thread = machine__find_thread(machine, event->fork.tid);
 
@@ -1067,7 +1073,7 @@ int machine__process_exit_event(struct machine *machine, union perf_event *event
                 perf_event__fprintf_task(event, stdout);
 
         if (thread != NULL)
-                machine__remove_thread(machine, thread);
+                thread__exited(thread);
 
         return 0;
 }
diff --git a/tools/perf/util/thread.h b/tools/perf/util/thread.h
index 13c62c909392..32d060164b52 100644
--- a/tools/perf/util/thread.h
+++ b/tools/perf/util/thread.h
@@ -16,6 +16,7 @@ struct thread {
         pid_t                   ppid;
         char                    shortname[3];
         bool                    comm_set;
+        bool                    dead; /* if set thread has exited */
         char                    *comm;
         int                     comm_len;
 
@@ -26,6 +27,10 @@ struct machine;
 
 struct thread *thread__new(pid_t tid);
 void thread__delete(struct thread *self);
+static inline void thread__exited(struct thread *thread)
+{
+        thread->dead = true;
+}
 
 int thread__set_comm(struct thread *self, const char *comm);
 int thread__comm_len(struct thread *self);