perf cs-etm: Support unknown_thread in cs_etm_auxtrace (46d53620) · Commits · 戴 / test

CoreSight doesn't allocate thread structure for unknown_thread in ETM auxtrace, so unknown_thread is NULL pointer. If the perf data doesn't contain valid tid and then cs_etm__mem_access() uses unknown_thread instead as thread handler, this results in a segmentation fault when thread__find_addr_map() accesses the thread handler. This commit creates a new thread data which is used by unknown_thread, so CoreSight tracing can roll back to use unknown_thread if perf data doesn't include valid thread info. This commit also releases thread data for initialization failure case and for normal auxtrace free flow. Signed-off-by:

Leo Yan <leo.yan@linaro.org> Acked-by:

Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1525924920-4381-1-git-send-email-leo.yan@linaro.org Signed-off-by:

Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/cs-etm.c

+22 −2

Original line number	Diff line number	Diff line
		@@ -239,6 +239,7 @@ static void cs_etm__free(struct perf_session *session)
		for (i = 0; i < aux->num_cpu; i++)
		zfree(&aux->metadata[i]);

		thread__zput(aux->unknown_thread);
		zfree(&aux->metadata);
		zfree(&aux);
		}
		@@ -1357,6 +1358,23 @@ int cs_etm__process_auxtrace_info(union perf_event *event,
		etm->auxtrace.free = cs_etm__free;
		session->auxtrace = &etm->auxtrace;

		etm->unknown_thread = thread__new(999999999, 999999999);
		if (!etm->unknown_thread)
		goto err_free_queues;

		/*
		* Initialize list node so that at thread__zput() we can avoid
		* segmentation fault at list_del_init().
		*/
		INIT_LIST_HEAD(&etm->unknown_thread->node);

		err = thread__set_comm(etm->unknown_thread, "unknown", 0);
		if (err)
		goto err_delete_thread;

		if (thread__init_map_groups(etm->unknown_thread, etm->machine))
		goto err_delete_thread;

		if (dump_trace) {
		cs_etm__print_auxtrace_info(auxtrace_info->priv, num_cpu);
		return 0;
		@@ -1371,16 +1389,18 @@ int cs_etm__process_auxtrace_info(union perf_event *event,

		err = cs_etm__synth_events(etm, session);
		if (err)
		goto err_free_queues;
		goto err_delete_thread;

		err = auxtrace_queues__process_index(&etm->queues, session);
		if (err)
		goto err_free_queues;
		goto err_delete_thread;

		etm->data_queued = etm->queues.populated;

		return 0;

		err_delete_thread:
		thread__zput(etm->unknown_thread);
		err_free_queues:
		auxtrace_queues__free(&etm->queues);
		session->auxtrace = NULL;

Admin message