Hi
As this is a sysfs only update - would it not be easier to simply use
a shell script to iterate through coresight/devices/ looking for
disable_source / disable_sink files and setting those accordingly?
See tools/perf/tests/shell/test_arm_coresight.sh for an example of a
script that does similar iteration to test coresight in perf
Regards
Mike
On Wed, 8 Feb 2023 at 11:16, Mao Jinlong <quic_jinlmao@xxxxxxxxxxx> wrote:
>
> Add sysfs node to reset all the sources and sinks. When mltiple
> sources are enabled, write 1 to reset_source_sink node to disable
> all sources and sinks.
>
> Signed-off-by: Mao Jinlong <quic_jinlmao@xxxxxxxxxxx>
> ---
> drivers/hwtracing/coresight/coresight-core.c | 106 +++++++++++++++++--
> 1 file changed, 99 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c
> index d3bf82c0de1d..06741ed2dee7 100644
> --- a/drivers/hwtracing/coresight/coresight-core.c
> +++ b/drivers/hwtracing/coresight/coresight-core.c
> @@ -458,6 +458,28 @@ static bool coresight_disable_source(struct coresight_device *csdev)
> return !csdev->enable;
> }
>
> +/**
> + * coresight_get_source - Get the source from the path
> + *
> + * @path: The list of devices.
> + *
> + * Returns the soruce csdev.
> + *
> + */
> +static struct coresight_device *coresight_get_source(struct list_head *path)
> +{
> + struct coresight_device *csdev;
> +
> + if (!path)
> + return NULL;
> +
> + csdev = list_first_entry(path, struct coresight_node, link)->csdev;
> + if (csdev->type != CORESIGHT_DEV_TYPE_SOURCE)
> + return NULL;
> +
> + return csdev;
> +}
> +
> /*
> * coresight_disable_path_from : Disable components in the given path beyond
> * @nd in the list. If @nd is NULL, all the components, except the SOURCE are
> @@ -1159,20 +1181,18 @@ int coresight_enable(struct coresight_device *csdev)
> }
> EXPORT_SYMBOL_GPL(coresight_enable);
>
> -void coresight_disable(struct coresight_device *csdev)
> +static void _coresight_disable(struct coresight_device *csdev)
> {
> int cpu, ret;
> struct list_head *path = NULL;
> u32 hash;
>
> - mutex_lock(&coresight_mutex);
> -
> ret = coresight_validate_source(csdev, __func__);
> if (ret)
> - goto out;
> + return;
>
> if (!csdev->enable || !coresight_disable_source(csdev))
> - goto out;
> + return;
>
> switch (csdev->subtype.source_subtype) {
> case CORESIGHT_DEV_SUBTYPE_SOURCE_PROC:
> @@ -1187,7 +1207,7 @@ void coresight_disable(struct coresight_device *csdev)
> path = idr_find(&path_idr, hash);
> if (path == NULL) {
> pr_err("Path is not found for %s\n", dev_name(&csdev->dev));
> - goto out;
> + return;
> }
> idr_remove(&path_idr, hash);
> break;
> @@ -1198,8 +1218,12 @@ void coresight_disable(struct coresight_device *csdev)
>
> coresight_disable_path(path);
> coresight_release_path(path);
> +}
>
> -out:
> +void coresight_disable(struct coresight_device *csdev)
> +{
> + mutex_lock(&coresight_mutex);
> + _coresight_disable(csdev);
> mutex_unlock(&coresight_mutex);
> }
> EXPORT_SYMBOL_GPL(coresight_disable);
> @@ -1761,8 +1785,76 @@ char *coresight_alloc_device_name(struct coresight_dev_list *dict,
> }
> EXPORT_SYMBOL_GPL(coresight_alloc_device_name);
>
> +/*
> + * Set the sink active status to false.
> + */
> +static int coresight_reset_sink(struct device *dev, void *data)
> +{
> + struct coresight_device *csdev = to_coresight_device(dev);
> +
> + if ((csdev->type == CORESIGHT_DEV_TYPE_SINK ||
> + csdev->type == CORESIGHT_DEV_TYPE_LINKSINK) &&
> + csdev->activated)
> + csdev->activated = false;
> +
> + return 0;
> +}
> +
> +static void coresight_reset_all_sink(void)
> +{
> + bus_for_each_dev(&coresight_bustype, NULL, NULL, coresight_reset_sink);
> +}
> +
> +static ssize_t reset_source_sink_store(struct bus_type *bus,
> + const char *buf, size_t size)
> +{
> + int id, cpu, ret = 0;
> + unsigned long val;
> + struct coresight_device *csdev;
> + struct list_head *path = NULL;
> +
> + ret = kstrtoul(buf, 10, &val);
> + if (ret)
> + return ret;
> +
> + mutex_lock(&coresight_mutex);
> +
> + /* Disable all per cpu sources */
> + for_each_present_cpu(cpu) {
> + path = per_cpu(tracer_path, cpu);
> + if (path) {
> + csdev = coresight_get_source(path);
> + if (!csdev)
> + continue;
> + }
> + _coresight_disable(csdev);
> + }
> +
> + /* Disable all sources which aren't associated with CPU */
> + idr_for_each_entry (&path_idr, path, id) {
> + csdev = coresight_get_source(path);
> + if (!csdev)
> + continue;
> +
> + _coresight_disable(csdev);
> + }
> + /* Reset all activated sinks */
> + coresight_reset_all_sink();
> +
> + mutex_unlock(&coresight_mutex);
> + return size;
> +}
> +static BUS_ATTR_WO(reset_source_sink);
> +
> +static struct attribute *coresight_reset_source_sink_attrs[] = {
> + &bus_attr_reset_source_sink.attr,
> + NULL,
> +};
> +ATTRIBUTE_GROUPS(coresight_reset_source_sink);
> +
> struct bus_type coresight_bustype = {
> .name = "coresight",
> + .bus_groups = coresight_reset_source_sink_groups,
> };
>
> static int __init coresight_init(void)
> --
> 2.39.0
>
--
Mike Leach
Principal Engineer, ARM Ltd.
Manchester Design Centre. UK
