Re: [PATCH 13/17] coresight: Pass trace ID map into source enable

From: Suzuki K Poulose
Date: Tue May 07 2024 - 06:50:21 EST


Hi James

On 29/04/2024 16:21, James Clark wrote:
This will allow Perf mode to pass in per-sink maps. System sources
allocate IDs on probe so they don't use this and it's __maybe_unused.

I am wondering if we need this change ? We have event_data associated with each event and we allocate the traceid from the sink map at setup_aux. So, why not set the traceid or even link the id_map in the event_data ?

something like:

struct etm_event_data {
struct work_struct work;
cpumask_t mask;
cpumask_t aux_hwid_done;
void *snk_config;
u32 cfg_hash;
struct list_head * __percpu *path;
+ u8 __percpu *traceid;
};


See my comment in the other patch.

Suzuki





Sysfs mode also has the global map hard coded in various places, so pass
in NULL when enabling for sysfs. We could bubble the global map all the
way down to where it's used, but it wouldn't have any functional
difference, so it's probably not worth the code churn.



Signed-off-by: James Clark <james.clark@xxxxxxx>
---
drivers/hwtracing/coresight/coresight-dummy.c | 3 ++-
drivers/hwtracing/coresight/coresight-etm-perf.c | 3 ++-
drivers/hwtracing/coresight/coresight-etm3x-core.c | 10 +++++-----
drivers/hwtracing/coresight/coresight-etm4x-core.c | 10 +++++-----
drivers/hwtracing/coresight/coresight-stm.c | 3 ++-
drivers/hwtracing/coresight/coresight-sysfs.c | 3 ++-
drivers/hwtracing/coresight/coresight-tpdm.c | 3 ++-
include/linux/coresight.h | 2 +-
8 files changed, 21 insertions(+), 16 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-dummy.c b/drivers/hwtracing/coresight/coresight-dummy.c
index ac70c0b491be..1f1b9ad160f6 100644
--- a/drivers/hwtracing/coresight/coresight-dummy.c
+++ b/drivers/hwtracing/coresight/coresight-dummy.c
@@ -21,7 +21,8 @@ DEFINE_CORESIGHT_DEVLIST(source_devs, "dummy_source");
DEFINE_CORESIGHT_DEVLIST(sink_devs, "dummy_sink");
static int dummy_source_enable(struct coresight_device *csdev,
- struct perf_event *event, enum cs_mode mode)
+ struct perf_event *event, enum cs_mode mode,
+ __maybe_unused struct coresight_trace_id_map *id_map)
{
dev_dbg(csdev->dev.parent, "Dummy source enabled\n");
diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
index 25f1f87c90d1..177cecae38d9 100644
--- a/drivers/hwtracing/coresight/coresight-etm-perf.c
+++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
@@ -496,7 +496,8 @@ static void etm_event_start(struct perf_event *event, int flags)
goto fail_end_stop;
/* Finally enable the tracer */
- if (source_ops(csdev)->enable(csdev, event, CS_MODE_PERF))
+ if (source_ops(csdev)->enable(csdev, event, CS_MODE_PERF,
+ coresight_trace_id_map_default()))
goto fail_disable_path;
/*
diff --git a/drivers/hwtracing/coresight/coresight-etm3x-core.c b/drivers/hwtracing/coresight/coresight-etm3x-core.c
index b21f5ad94e63..b310bdf19038 100644
--- a/drivers/hwtracing/coresight/coresight-etm3x-core.c
+++ b/drivers/hwtracing/coresight/coresight-etm3x-core.c
@@ -482,7 +482,8 @@ void etm_release_trace_id(struct etm_drvdata *drvdata)
}
static int etm_enable_perf(struct coresight_device *csdev,
- struct perf_event *event)
+ struct perf_event *event,
+ struct coresight_trace_id_map *id_map)
{
struct etm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
int trace_id;
@@ -501,8 +502,7 @@ static int etm_enable_perf(struct coresight_device *csdev,
* with perf locks - we know the ID cannot change until perf shuts down
* the session
*/
- trace_id = coresight_trace_id_read_cpu_id(drvdata->cpu,
- coresight_trace_id_map_default());
+ trace_id = coresight_trace_id_read_cpu_id(drvdata->cpu, id_map);
if (!IS_VALID_CS_TRACE_ID(trace_id)) {
dev_err(&drvdata->csdev->dev, "Failed to set trace ID for %s on CPU%d\n",
dev_name(&drvdata->csdev->dev), drvdata->cpu);
@@ -555,7 +555,7 @@ static int etm_enable_sysfs(struct coresight_device *csdev)
}
static int etm_enable(struct coresight_device *csdev, struct perf_event *event,
- enum cs_mode mode)
+ enum cs_mode mode, struct coresight_trace_id_map *id_map)
{
int ret;
struct etm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
@@ -570,7 +570,7 @@ static int etm_enable(struct coresight_device *csdev, struct perf_event *event,
ret = etm_enable_sysfs(csdev);
break;
case CS_MODE_PERF:
- ret = etm_enable_perf(csdev, event);
+ ret = etm_enable_perf(csdev, event, id_map);
break;
default:
ret = -EINVAL;
diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
index d16d6efb26fa..02dbb6c4daf5 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
@@ -753,7 +753,8 @@ static int etm4_parse_event_config(struct coresight_device *csdev,
}
static int etm4_enable_perf(struct coresight_device *csdev,
- struct perf_event *event)
+ struct perf_event *event,
+ struct coresight_trace_id_map *id_map)
{
int ret = 0, trace_id;
struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
@@ -776,8 +777,7 @@ static int etm4_enable_perf(struct coresight_device *csdev,
* with perf locks - we know the ID cannot change until perf shuts down
* the session
*/
- trace_id = coresight_trace_id_read_cpu_id(drvdata->cpu,
- coresight_trace_id_map_default());
+ trace_id = coresight_trace_id_read_cpu_id(drvdata->cpu, id_map);
if (!IS_VALID_CS_TRACE_ID(trace_id)) {
dev_err(&drvdata->csdev->dev, "Failed to set trace ID for %s on CPU%d\n",
dev_name(&drvdata->csdev->dev), drvdata->cpu);
@@ -839,7 +839,7 @@ static int etm4_enable_sysfs(struct coresight_device *csdev)
}
static int etm4_enable(struct coresight_device *csdev, struct perf_event *event,
- enum cs_mode mode)
+ enum cs_mode mode, struct coresight_trace_id_map *id_map)
{
int ret;
@@ -853,7 +853,7 @@ static int etm4_enable(struct coresight_device *csdev, struct perf_event *event,
ret = etm4_enable_sysfs(csdev);
break;
case CS_MODE_PERF:
- ret = etm4_enable_perf(csdev, event);
+ ret = etm4_enable_perf(csdev, event, id_map);
break;
default:
ret = -EINVAL;
diff --git a/drivers/hwtracing/coresight/coresight-stm.c b/drivers/hwtracing/coresight/coresight-stm.c
index e1c62820dfda..a80ad1de4c23 100644
--- a/drivers/hwtracing/coresight/coresight-stm.c
+++ b/drivers/hwtracing/coresight/coresight-stm.c
@@ -194,7 +194,8 @@ static void stm_enable_hw(struct stm_drvdata *drvdata)
}
static int stm_enable(struct coresight_device *csdev, struct perf_event *event,
- enum cs_mode mode)
+ enum cs_mode mode,
+ __maybe_unused struct coresight_trace_id_map *trace_id)
{
struct stm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
diff --git a/drivers/hwtracing/coresight/coresight-sysfs.c b/drivers/hwtracing/coresight/coresight-sysfs.c
index 1e67cc7758d7..a01c9e54e2ed 100644
--- a/drivers/hwtracing/coresight/coresight-sysfs.c
+++ b/drivers/hwtracing/coresight/coresight-sysfs.c
@@ -9,6 +9,7 @@
#include <linux/kernel.h>
#include "coresight-priv.h"
+#include "coresight-trace-id.h"
/*
* Use IDR to map the hash of the source's device name
@@ -63,7 +64,7 @@ static int coresight_enable_source_sysfs(struct coresight_device *csdev,
*/
lockdep_assert_held(&coresight_mutex);
if (coresight_get_mode(csdev) != CS_MODE_SYSFS) {
- ret = source_ops(csdev)->enable(csdev, data, mode);
+ ret = source_ops(csdev)->enable(csdev, data, mode, NULL);
if (ret)
return ret;
}
diff --git a/drivers/hwtracing/coresight/coresight-tpdm.c b/drivers/hwtracing/coresight/coresight-tpdm.c
index a9708ab0d488..0376ad326a2f 100644
--- a/drivers/hwtracing/coresight/coresight-tpdm.c
+++ b/drivers/hwtracing/coresight/coresight-tpdm.c
@@ -439,7 +439,8 @@ static void __tpdm_enable(struct tpdm_drvdata *drvdata)
}
static int tpdm_enable(struct coresight_device *csdev, struct perf_event *event,
- enum cs_mode mode)
+ enum cs_mode mode,
+ __maybe_unused struct coresight_trace_id_map *id_map)
{
struct tpdm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
diff --git a/include/linux/coresight.h b/include/linux/coresight.h
index 7d62b88bfb5c..3a678e5425dc 100644
--- a/include/linux/coresight.h
+++ b/include/linux/coresight.h
@@ -384,7 +384,7 @@ struct coresight_ops_link {
struct coresight_ops_source {
int (*cpu_id)(struct coresight_device *csdev);
int (*enable)(struct coresight_device *csdev, struct perf_event *event,
- enum cs_mode mode);
+ enum cs_mode mode, struct coresight_trace_id_map *id_map);
void (*disable)(struct coresight_device *csdev,
struct perf_event *event);
};