Commit d87d76d8 authored by Jie Gan's avatar Jie Gan Committed by Suzuki K Poulose
Browse files

Coresight: Allocate trace ID after building the path 



The trace_id will be stored in coresight_path instead of being declared
everywhere and allocated after building the path.

Co-developed-by: default avatarJames Clark <james.clark@linaro.org>
Signed-off-by: default avatarJames Clark <james.clark@linaro.org>
Signed-off-by: default avatarJie Gan <quic_jiegan@quicinc.com>
Signed-off-by: default avatarSuzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250303032931.2500935-6-quic_jiegan@quicinc.com
parent 3c03c49b

drivers/hwtracing/coresight/coresight-core.c

+44 −0
Original line number Diff line number Diff line
@@ -655,6 +655,50 @@ static void coresight_drop_device(struct coresight_device *csdev) 
	}

}



/*

 * coresight device will read their existing or alloc a trace ID, if their trace_id

 * callback is set.

 *

 * Return 0 if the trace_id callback is not set.

 * Return the result of the trace_id callback if it is set. The return value

 * will be the trace_id if successful, and an error number if it fails.

 */

static int coresight_get_trace_id(struct coresight_device *csdev,

				  enum cs_mode mode,

				  struct coresight_device *sink)

{

	if (coresight_ops(csdev)->trace_id)

		return coresight_ops(csdev)->trace_id(csdev, mode, sink);



	return 0;

}



/*

 * Call this after creating the path and before enabling it. This leaves

 * the trace ID set on the path, or it remains 0 if it couldn't be assigned.

 */

void coresight_path_assign_trace_id(struct coresight_path *path,

				    enum cs_mode mode)

{

	struct coresight_device *sink = coresight_get_sink(&path->path_list);

	struct coresight_node *nd;

	int trace_id;



	list_for_each_entry(nd, &path->path_list, link) {

		/* Assign a trace ID to the path for the first device that wants to do it */

		trace_id = coresight_get_trace_id(nd->csdev, mode, sink);



		/*

		 * 0 in this context is that it didn't want to assign so keep searching.

		 * Non 0 is either success or fail.

		 */

		if (trace_id != 0) {

			path->trace_id = trace_id;

			return;

		}

	}

}



/**

 * _coresight_build_path - recursively build a path from a @csdev to a sink.

 * @csdev:	The device to start from.

drivers/hwtracing/coresight/coresight-etm-perf.c

+2 −3
Original line number Diff line number Diff line
@@ -319,7 +319,6 @@ static void *etm_setup_aux(struct perf_event *event, void **pages, 
{

	u32 id, cfg_hash;

	int cpu = event->cpu;

	int trace_id;

	cpumask_t *mask;

	struct coresight_device *sink = NULL;

	struct coresight_device *user_sink = NULL, *last_sink = NULL;
@@ -409,8 +408,8 @@ static void *etm_setup_aux(struct perf_event *event, void **pages, 
		}



		/* ensure we can allocate a trace ID for this CPU */

		trace_id = coresight_trace_id_get_cpu_id_map(cpu, &sink->perf_sink_id_map);

		if (!IS_VALID_CS_TRACE_ID(trace_id)) {

		coresight_path_assign_trace_id(path, CS_MODE_PERF);

		if (!IS_VALID_CS_TRACE_ID(path->trace_id)) {

			cpumask_clear_cpu(cpu, mask);

			coresight_release_path(path);

			continue;

drivers/hwtracing/coresight/coresight-priv.h

+2 −0
Original line number Diff line number Diff line
@@ -152,6 +152,8 @@ int coresight_make_links(struct coresight_device *orig, 
void coresight_remove_links(struct coresight_device *orig,

			    struct coresight_connection *conn);

u32 coresight_get_sink_id(struct coresight_device *csdev);

void coresight_path_assign_trace_id(struct coresight_path *path,

				   enum cs_mode mode);



#if IS_ENABLED(CONFIG_CORESIGHT_SOURCE_ETM3X)

extern int etm_readl_cp14(u32 off, unsigned int *val);

drivers/hwtracing/coresight/coresight-sysfs.c

+4 −0
Original line number Diff line number Diff line
@@ -209,6 +209,10 @@ int coresight_enable_sysfs(struct coresight_device *csdev) 
		goto out;

	}



	coresight_path_assign_trace_id(path, CS_MODE_SYSFS);

	if (!IS_VALID_CS_TRACE_ID(path->trace_id))

		goto err_path;



	ret = coresight_enable_path(&path->path_list, CS_MODE_SYSFS, NULL);

	if (ret)

		goto err_path;