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path: root/drivers/hwtracing/coresight/coresight-etm-perf.c
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Diffstat (limited to 'drivers/hwtracing/coresight/coresight-etm-perf.c')
-rw-r--r--drivers/hwtracing/coresight/coresight-etm-perf.c59
1 files changed, 43 insertions, 16 deletions
diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
index 8a0ad77574e7..69349b93e874 100644
--- a/drivers/hwtracing/coresight/coresight-etm-perf.c
+++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
@@ -23,6 +23,7 @@
#include <linux/mm.h>
#include <linux/init.h>
#include <linux/perf_event.h>
+#include <linux/percpu-defs.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/workqueue.h>
@@ -44,7 +45,7 @@ struct etm_event_data {
struct work_struct work;
cpumask_t mask;
void *snk_config;
- struct list_head **path;
+ struct list_head * __percpu *path;
};
static DEFINE_PER_CPU(struct perf_output_handle, ctx_handle);
@@ -72,6 +73,18 @@ static const struct attribute_group *etm_pmu_attr_groups[] = {
NULL,
};
+static inline struct list_head **
+etm_event_cpu_path_ptr(struct etm_event_data *data, int cpu)
+{
+ return per_cpu_ptr(data->path, cpu);
+}
+
+static inline struct list_head *
+etm_event_cpu_path(struct etm_event_data *data, int cpu)
+{
+ return *etm_event_cpu_path_ptr(data, cpu);
+}
+
static void etm_event_read(struct perf_event *event) {}
static int etm_addr_filters_alloc(struct perf_event *event)
@@ -131,23 +144,26 @@ static void free_event_data(struct work_struct *work)
*/
if (event_data->snk_config) {
cpu = cpumask_first(mask);
- sink = coresight_get_sink(event_data->path[cpu]);
+ 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);
}
for_each_cpu(cpu, mask) {
- if (!(IS_ERR_OR_NULL(event_data->path[cpu])))
- coresight_release_path(event_data->path[cpu]);
+ struct list_head **ppath;
+
+ ppath = etm_event_cpu_path_ptr(event_data, cpu);
+ if (!(IS_ERR_OR_NULL(*ppath)))
+ coresight_release_path(*ppath);
+ *ppath = NULL;
}
- kfree(event_data->path);
+ free_percpu(event_data->path);
kfree(event_data);
}
static void *alloc_event_data(int cpu)
{
- int size;
cpumask_t *mask;
struct etm_event_data *event_data;
@@ -158,7 +174,6 @@ static void *alloc_event_data(int cpu)
/* Make sure nothing disappears under us */
get_online_cpus();
- size = num_online_cpus();
mask = &event_data->mask;
if (cpu != -1)
@@ -175,8 +190,8 @@ static void *alloc_event_data(int cpu)
* unused memory when dealing with single CPU trace scenarios is small
* compared to the cost of searching through an optimized array.
*/
- event_data->path = kcalloc(size,
- sizeof(struct list_head *), GFP_KERNEL);
+ event_data->path = alloc_percpu(struct list_head *);
+
if (!event_data->path) {
kfree(event_data);
return NULL;
@@ -224,6 +239,7 @@ static void *etm_setup_aux(int event_cpu, void **pages,
/* Setup the path for each CPU in a trace session */
for_each_cpu(cpu, mask) {
+ struct list_head *path;
struct coresight_device *csdev;
csdev = per_cpu(csdev_src, cpu);
@@ -235,9 +251,11 @@ static void *etm_setup_aux(int event_cpu, void **pages,
* list of devices from source to sink that can be
* referenced later when the path is actually needed.
*/
- event_data->path[cpu] = coresight_build_path(csdev, sink);
- if (IS_ERR(event_data->path[cpu]))
+ path = coresight_build_path(csdev, sink);
+ if (IS_ERR(path))
goto err;
+
+ *etm_event_cpu_path_ptr(event_data, cpu) = path;
}
if (!sink_ops(sink)->alloc_buffer)
@@ -266,6 +284,7 @@ static void etm_event_start(struct perf_event *event, int flags)
struct etm_event_data *event_data;
struct perf_output_handle *handle = this_cpu_ptr(&ctx_handle);
struct coresight_device *sink, *csdev = per_cpu(csdev_src, cpu);
+ struct list_head *path;
if (!csdev)
goto fail;
@@ -278,8 +297,9 @@ static void etm_event_start(struct perf_event *event, int flags)
if (!event_data)
goto fail;
+ path = etm_event_cpu_path(event_data, cpu);
/* We need a sink, no need to continue without one */
- sink = coresight_get_sink(event_data->path[cpu]);
+ sink = coresight_get_sink(path);
if (WARN_ON_ONCE(!sink || !sink_ops(sink)->set_buffer))
goto fail_end_stop;
@@ -289,7 +309,7 @@ static void etm_event_start(struct perf_event *event, int flags)
goto fail_end_stop;
/* Nothing will happen without a path */
- if (coresight_enable_path(event_data->path[cpu], CS_MODE_PERF))
+ if (coresight_enable_path(path, CS_MODE_PERF))
goto fail_end_stop;
/* Tell the perf core the event is alive */
@@ -297,11 +317,13 @@ static void etm_event_start(struct perf_event *event, int flags)
/* Finally enable the tracer */
if (source_ops(csdev)->enable(csdev, event, CS_MODE_PERF))
- goto fail_end_stop;
+ goto fail_disable_path;
out:
return;
+fail_disable_path:
+ coresight_disable_path(path);
fail_end_stop:
perf_aux_output_flag(handle, PERF_AUX_FLAG_TRUNCATED);
perf_aux_output_end(handle, 0);
@@ -317,6 +339,7 @@ static void etm_event_stop(struct perf_event *event, int mode)
struct coresight_device *sink, *csdev = per_cpu(csdev_src, cpu);
struct perf_output_handle *handle = this_cpu_ptr(&ctx_handle);
struct etm_event_data *event_data = perf_get_aux(handle);
+ struct list_head *path;
if (event->hw.state == PERF_HES_STOPPED)
return;
@@ -324,7 +347,11 @@ static void etm_event_stop(struct perf_event *event, int mode)
if (!csdev)
return;
- sink = coresight_get_sink(event_data->path[cpu]);
+ path = etm_event_cpu_path(event_data, cpu);
+ if (!path)
+ return;
+
+ sink = coresight_get_sink(path);
if (!sink)
return;
@@ -355,7 +382,7 @@ static void etm_event_stop(struct perf_event *event, int mode)
}
/* Disabling the path make its elements available to other sessions */
- coresight_disable_path(event_data->path[cpu]);
+ coresight_disable_path(path);
}
static int etm_event_add(struct perf_event *event, int mode)