Hi Mathieu,
diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c index 1a3169e69bb1..25041d2654e3 100644 --- a/drivers/hwtracing/coresight/coresight-etm-perf.c +++ b/drivers/hwtracing/coresight/coresight-etm-perf.c @@ -223,7 +223,7 @@ static void *etm_setup_aux(struct perf_event *event, void **pages, id = (u32)event->attr.config2; sink = coresight_get_sink_by_id(id); } else {
sink = coresight_get_enabled_sink(true);
sink = coresight_get_enabled_sink(NULL, true);It is time for this subsystem to move out of the prehistoric age. Please remove the call to coresight_get_enabled_sink() entirely. In the change log you can write that selecting a sink from sysfs is deprecated when using the perf interface. I will personally refactor the code if someone complains that it broke their user space.
Okay fine.
} mask = &event_data->mask; diff --git a/drivers/hwtracing/coresight/coresight-priv.h b/drivers/hwtracing/coresight/coresight-priv.h index f2dc625ea585..010ed26db340 100644 --- a/drivers/hwtracing/coresight/coresight-priv.h +++ b/drivers/hwtracing/coresight/coresight-priv.h @@ -148,10 +148,13 @@ static inline void coresight_write_reg_pair(void __iomem *addr, u64 val, void coresight_disable_path(struct list_head *path); int coresight_enable_path(struct list_head *path, u32 mode, void *sink_data); struct coresight_device *coresight_get_sink(struct list_head *path); -struct coresight_device *coresight_get_enabled_sink(bool reset); +struct coresight_device * +coresight_get_enabled_sink(struct coresight_device *source, bool reset); struct coresight_device *coresight_get_sink_by_id(u32 id); struct coresight_device * coresight_find_default_sink(struct coresight_device *csdev); +struct coresight_device * +coresight_find_enabled_sink(struct coresight_device *csdev); struct list_head *coresight_build_path(struct coresight_device *csdev, struct coresight_device *sink); void coresight_release_path(struct list_head *path); diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c index e9c90f2de34a..ae69169c58d3 100644 --- a/drivers/hwtracing/coresight/coresight.c +++ b/drivers/hwtracing/coresight/coresight.c @@ -566,6 +566,10 @@ static int coresight_enabled_sink(struct device *dev, const void *data) /**
- coresight_get_enabled_sink - returns the first enabled sink found on the bus
- When a source reference is given, enabled sink is found using connection based
- search.
- @source: Coresight source device reference
- @deactivate: Whether the 'enable_sink' flag should be reset
- When operated from perf the deactivate parameter should be set to 'true'.
@@ -576,10 +580,21 @@ static int coresight_enabled_sink(struct device *dev, const void *data)
- parameter should be set to 'false', hence mandating users to explicitly
- clear the flag.
*/ -struct coresight_device *coresight_get_enabled_sink(bool deactivate) +struct coresight_device * +coresight_get_enabled_sink(struct coresight_device *source, bool deactivate)
This code was written during a time when all sources were able to reach a sink, something that is no longer the case. Starting from a source is the right way to go.
{ struct device *dev = NULL;
- struct coresight_device *sink;
- if (!source)
goto bus_search;Return NULL if a source was not given.
Agree, since we are removing invocations from perf.
- sink = coresight_find_enabled_sink(source);
- if (sink && deactivate)
sink->activated = false;- return sink;
You get credits for trying to re-use code but in this case I would like to avoid modifying coresight_find_sink() to keep it as simple as possible. I suggest to copy the for() loop in coresight_find_sink() and stop the search when the first activated sink is found. It will introduce a little bit of code duplication but I think we will gain a lot in maintainability.
Fine.
+bus_search: dev = bus_find_device(&coresight_bustype, NULL, &deactivate, coresight_enabled_sink);
Get rid of this. You can also get rid of the 'deactivate' parameter since it won't be used anymore.
Agree, since perf doesnt require this anymore.
Let me know if you have questions.
Sure. Thanks.