Re: [PATCH v1 05/11] coresight: Save activated path into source device

On 16/05/2025 5:07 pm, Leo Yan wrote:

For a source device, save activated path into the coresight_device structure.

This will be used by sequential changes for controlling the path during CPU idle.

Signed-off-by: Leo Yan leo.yan@arm.com

drivers/hwtracing/coresight/coresight-core.c | 10 ++++++++++ include/linux/coresight.h | 3 +++ 2 files changed, 13 insertions(+)

diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c index 7ab7321ca8d5..8f565bb3c535 100644 --- a/drivers/hwtracing/coresight/coresight-core.c +++ b/drivers/hwtracing/coresight/coresight-core.c @@ -495,6 +495,12 @@ static void coresight_disable_path_from(struct coresight_path *path, void coresight_disable_path(struct coresight_path *path) {

• struct coresight_device *source;
• source = coresight_get_source(path);
• if (coresight_is_percpu_source(source))

• source->path = NULL;
  

• coresight_disable_path_from(path, NULL); } EXPORT_SYMBOL_GPL(coresight_disable_path);

@@ -577,6 +583,10 @@ int coresight_enable_path(struct coresight_path *path, enum cs_mode mode, } }

• source = coresight_get_source(path);
• if (coresight_is_percpu_source(source))

• source->path = path;
  

• out: return ret; err_disable_helpers:

diff --git a/include/linux/coresight.h b/include/linux/coresight.h index 64cee4040daa..cd9709a36b9c 100644 --- a/include/linux/coresight.h +++ b/include/linux/coresight.h @@ -265,6 +265,7 @@ struct coresight_trace_id_map {

• CS_MODE_SYSFS. Otherwise it must be accessed from inside the
  

• spinlock.
  

• @orphan: true if the component has connections that haven't been linked.

• • @path: activated path pointer (only used for source device).
  • @sysfs_sink_activated: 'true' when a sink has been selected for use via sysfs

  • by writing a 1 to the 'enable_sink' file.  A sink can be
    

  • activated but not yet enabled.  Enabling for a _sink_ happens
    

@@ -291,6 +292,8 @@ struct coresight_device { local_t mode; int refcnt; bool orphan;

• /* activated path (for source only) */
• struct coresight_path *path;

This is probably cleaner if it's saved in the new global per-cpu you added in patch 2. It's even more specific than "for source only", it's actually only for per-cpu sources so it's not worth having it on every device.

/* sink specific fields */ bool sysfs_sink_activated; struct dev_ext_attribute *ea;