[PATCH v2 08/16] coresight: perf: Clean up function etm_setup_aux()

Mathieu Poirier mathieu.poirier at linaro.org
Mon Mar 25 14:56:24 PDT 2019


There is no point in allocating sink memory for a trace session if
there is not a way to free it once it is no longer needed.  As such make
sure the sink API function to allocate and free memory have been
implemented before moving ahead with the establishment of a trace
session.

Signed-off-by: Mathieu Poirier <mathieu.poirier at linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose at arm.com>
---
 drivers/hwtracing/coresight/coresight-etm-perf.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
index bbfed70b3402..b8ca3800b56b 100644
--- a/drivers/hwtracing/coresight/coresight-etm-perf.c
+++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
@@ -134,8 +134,7 @@ static void free_event_data(struct work_struct *work)
 	if (event_data->snk_config && !WARN_ON(cpumask_empty(mask))) {
 		cpu = cpumask_first(mask);
 		sink = coresight_get_sink(etm_event_cpu_path(event_data, cpu));
-		if (sink_ops(sink)->free_buffer)
-			sink_ops(sink)->free_buffer(event_data->snk_config);
+		sink_ops(sink)->free_buffer(event_data->snk_config);
 	}
 
 	for_each_cpu(cpu, mask) {
@@ -215,7 +214,7 @@ static void *etm_setup_aux(struct perf_event *event, void **pages,
 		sink = coresight_get_enabled_sink(true);
 	}
 
-	if (!sink || !sink_ops(sink)->alloc_buffer)
+	if (!sink)
 		goto err;
 
 	mask = &event_data->mask;
@@ -261,6 +260,9 @@ static void *etm_setup_aux(struct perf_event *event, void **pages,
 	if (cpu >= nr_cpu_ids)
 		goto err;
 
+	if (!sink_ops(sink)->alloc_buffer || !sink_ops(sink)->free_buffer)
+		goto err;
+
 	/* Allocate the sink buffer for this session */
 	event_data->snk_config =
 			sink_ops(sink)->alloc_buffer(sink, cpu, pages,
-- 
2.17.1




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