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charset="UTF-8" In tpebs_stop(), read tpebs_reader_thread into a local variable before releasing tpebs_mtx to call pthread_join(). Transfer ownership of tpebs_cmd.out to __sample_reader() by passing it as the thread argument and setting tpebs_cmd.out = -1 in evsel__tpebs_open() so tpebs_stop() does not double-close the fd closed by perf_session__delete(). Also reset tpebs_cmd.pid = 0 and tpebs_cmd.out = -1 and return early if start_command() fails in evsel__tpebs_start_perf_record(), as start_command() closes the pipe internally and may leave cmd->pid = -1 on error, and join tpebs_reader_thread on error in evsel__tpebs_open() if it was already started. Include , , , , , and explicitly. Signed-off-by: Ian Rogers --- tools/perf/util/intel-tpebs.c | 51 ++++++++++++++++++++++++++++++----- 1 file changed, 44 insertions(+), 7 deletions(-) diff --git a/tools/perf/util/intel-tpebs.c b/tools/perf/util/intel-tpebs.c index 7c0b8b15bd10..47c939fc2058 100644 --- a/tools/perf/util/intel-tpebs.c +++ b/tools/perf/util/intel-tpebs.c @@ -27,6 +27,12 @@ #include #include #include +#include +#include +#include +#include +#include +#include #define PERF_DATA "-" @@ -120,10 +126,15 @@ static int evsel__tpebs_start_perf_record(struct evsel *evsel) tpebs_cmd.out = -1; ret = start_command(&tpebs_cmd); zfree(&tpebs_cmd.argv); + if (ret) { + tpebs_cmd.pid = 0; + tpebs_cmd.out = -1; + return ret; + } list_for_each_entry(t, &tpebs_results, nd) t->started = true; - return ret; + return 0; } static bool is_child_pid(pid_t parent, pid_t child) @@ -220,13 +231,13 @@ static int process_sample_event(const struct perf_tool *tool __maybe_unused, return 0; } -static void *__sample_reader(void *arg __maybe_unused) +static void *__sample_reader(void *arg) { struct perf_session *session; struct perf_data data = { .mode = PERF_DATA_MODE_READ, .path = PERF_DATA, - .file.fd = tpebs_cmd.out, + .file.fd = (int)(intptr_t)arg, }; struct perf_tool tool; @@ -236,8 +247,10 @@ static void *__sample_reader(void *arg __maybe_unused) tool.attr = perf_event__process_attr; session = perf_session__new(&data, &tool); - if (IS_ERR(session)) + if (IS_ERR(session)) { + close(data.file.fd); return NULL; + } perf_session__process_events(session); perf_session__delete(session); @@ -331,12 +344,19 @@ static int tpebs_stop(void) __must_hold(tpebs_mtx_get()) /* Like tpebs_start, we should only run tpebs_end once. */ if (tpebs_cmd.pid != 0) { pid_t actual_pid = tpebs_cmd.pid; + pthread_t reader_thread; tpebs_stopping = true; tpebs_send_record_cmd(EVLIST_CTL_CMD_STOP_TAG); + /* + * tpebs_results is empty when stopping; clear pid so + * process_sample_event() ignores any late samples while + * draining the pipe. + */ tpebs_cmd.pid = 0; + reader_thread = tpebs_reader_thread; mutex_unlock(tpebs_mtx_get()); - pthread_join(tpebs_reader_thread, NULL); + pthread_join(reader_thread, NULL); mutex_lock(tpebs_mtx_get()); if (control_fd[0] >= 0) { close(control_fd[0]); @@ -515,6 +535,7 @@ int evsel__tpebs_open(struct evsel *evsel) int ret; bool tpebs_empty; bool started_process = false; + bool started_thread = false; /* We should only run tpebs_start when tpebs_recording is enabled. */ if (!tpebs_recording) @@ -567,12 +588,15 @@ int evsel__tpebs_open(struct evsel *evsel) goto out; if (pthread_create(&tpebs_reader_thread, /*attr=*/NULL, __sample_reader, - /*arg=*/NULL)) { + (void *)(intptr_t)tpebs_cmd.out)) { kill(tpebs_cmd.pid, SIGTERM); pr_err("Could not create thread to process sample data.\n"); ret = -1; goto out; } + /* __sample_reader now owns and closes the output fd. */ + tpebs_cmd.out = -1; + started_thread = true; ret = tpebs_send_record_cmd(EVLIST_CTL_CMD_ENABLE_TAG); } out: @@ -586,9 +610,22 @@ int evsel__tpebs_open(struct evsel *evsel) if (started_process) { if (tpebs_cmd.pid > 0) { - kill(tpebs_cmd.pid, SIGTERM); + pid_t actual_pid = tpebs_cmd.pid; + + tpebs_stopping = true; + kill(actual_pid, SIGTERM); + tpebs_cmd.pid = 0; + if (started_thread) { + pthread_t reader_thread = tpebs_reader_thread; + + mutex_unlock(tpebs_mtx_get()); + pthread_join(reader_thread, NULL); + mutex_lock(tpebs_mtx_get()); + } + tpebs_cmd.pid = actual_pid; finish_command(&tpebs_cmd); tpebs_cmd.pid = 0; + tpebs_stopping = false; } if (tpebs_cmd.out >= 0) { close(tpebs_cmd.out); -- 2.56.0.455.g6c5a503b38-goog