After thread is added to machine->threads[i].dead in
__machine__remove_thread, the machine->threads[i].dead is freed
when calling free(session) in perf_session__delete(). So it get a
Segmentation fault when accessing it in thread__put().

In this patch, we delay the perf_session__delete until all threads
have been deleted.

This can be reproduced by following steps:
        ulimit -c unlimited
        export MALLOC_MMAP_THRESHOLD_=0
        perf sched record sleep 10
        perf sched latency --sort max
        Segmentation fault (core dumped)

Signed-off-by: Zhipeng Xie <xiezhipe...@huawei.com>
Signed-off-by: Wei Li <liwei...@huawei.com>
---
 tools/perf/builtin-sched.c | 44 ++++++++++++++++++++++++++++++++++++--
 1 file changed, 42 insertions(+), 2 deletions(-)

diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c
index cbf39dab19c1..17849ae2eb1e 100644
--- a/tools/perf/builtin-sched.c
+++ b/tools/perf/builtin-sched.c
@@ -3130,11 +3130,48 @@ static void perf_sched__merge_lat(struct perf_sched 
*sched)
 static int perf_sched__lat(struct perf_sched *sched)
 {
        struct rb_node *next;
+       const struct perf_evsel_str_handler handlers[] = {
+               { "sched:sched_switch",       process_sched_switch_event, },
+               { "sched:sched_stat_runtime", process_sched_runtime_event, },
+               { "sched:sched_wakeup",       process_sched_wakeup_event, },
+               { "sched:sched_wakeup_new",   process_sched_wakeup_event, },
+               { "sched:sched_migrate_task", process_sched_migrate_task_event, 
},
+       };
+       struct perf_session *session;
+       struct perf_data data = {
+               .file      = {
+                       .path = input_name,
+               },
+               .mode      = PERF_DATA_MODE_READ,
+               .force     = sched->force,
+       };
+       int rc = -1;
 
        setup_pager();
 
-       if (perf_sched__read_events(sched))
+       session = perf_session__new(&data, false, &sched->tool);
+       if (session == NULL) {
+               pr_debug("No Memory for session\n");
                return -1;
+       }
+
+       symbol__init(&session->header.env);
+
+       if (perf_session__set_tracepoints_handlers(session, handlers))
+               goto out_delete;
+
+       if (perf_session__has_traces(session, "record -R")) {
+               int err = perf_session__process_events(session);
+
+               if (err) {
+                       pr_err("Failed to process events, error %d", err);
+                       goto out_delete;
+               }
+
+               sched->nr_events      = session->evlist->stats.nr_events[0];
+               sched->nr_lost_events = session->evlist->stats.total_lost;
+               sched->nr_lost_chunks = 
session->evlist->stats.nr_events[PERF_RECORD_LOST];
+       }
 
        perf_sched__merge_lat(sched);
        perf_sched__sort_lat(sched);
@@ -3163,7 +3200,10 @@ static int perf_sched__lat(struct perf_sched *sched)
        print_bad_events(sched);
        printf("\n");
 
-       return 0;
+       rc = 0;
+out_delete:
+       perf_session__delete(session);
+       return rc;
 }
 
 static int setup_map_cpus(struct perf_sched *sched)
-- 
2.17.1

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