linux-kernel - [PATCH 22/32] coresight: perf: Refactor function free_event

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Date:   Thu, 25 Apr 2019 13:53:00 -0600
From:   Mathieu Poirier <mathieu.poirier@...aro.org>
To:     gregkh@...uxfoundation.org
Cc:     linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org
Subject: [PATCH 22/32] coresight: perf: Refactor function free_event_data()

Function free_event_data() is already busy and is bound to become
worse with the addition of CPU-wide trace scenarios.  As such spin
off a new function to strickly take care of the sink buffers.

Signed-off-by: Mathieu Poirier <mathieu.poirier@...aro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@....com>
Tested-by: Leo Yan <leo.yan@...aro.org>
Tested-by: Robert Walker <robert.walker@....com>
---
 .../hwtracing/coresight/coresight-etm-perf.c  | 24 ++++++++++++++-----
 1 file changed, 18 insertions(+), 6 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
index b8ca3800b56b..806b3dd5872d 100644
--- a/drivers/hwtracing/coresight/coresight-etm-perf.c
+++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
@@ -120,22 +120,34 @@ static int etm_event_init(struct perf_event *event)
 	return ret;
 }
 
+static void free_sink_buffer(struct etm_event_data *event_data)
+{
+	int cpu;
+	cpumask_t *mask = &event_data->mask;
+	struct coresight_device *sink;
+
+	if (WARN_ON(cpumask_empty(mask)))
+		return;
+
+	if (!event_data->snk_config)
+		return;
+
+	cpu = cpumask_first(mask);
+	sink = coresight_get_sink(etm_event_cpu_path(event_data, cpu));
+	sink_ops(sink)->free_buffer(event_data->snk_config);
+}
+
 static void free_event_data(struct work_struct *work)
 {
 	int cpu;
 	cpumask_t *mask;
 	struct etm_event_data *event_data;
-	struct coresight_device *sink;
 
 	event_data = container_of(work, struct etm_event_data, work);
 	mask = &event_data->mask;
 
 	/* Free the sink buffers, if there are any */
-	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));
-		sink_ops(sink)->free_buffer(event_data->snk_config);
-	}
+	free_sink_buffer(event_data);
 
 	for_each_cpu(cpu, mask) {
 		struct list_head **ppath;
-- 
2.17.1