Re: [PATCH v4 04/10] coresight: etm-perf: update to handle configuration selection
From: Suzuki K Poulose
Date: Thu Mar 04 2021 - 07:15:13 EST
On 1/28/21 5:09 PM, Mike Leach wrote:
Loaded coresight configurations are registered in the cs_etm\cs_config sub
directory. This extends the etm-perf code to handle these registrations,
and the cs_syscfg driver to perform the registration on load.
Signed-off-by: Mike Leach <mike.leach@xxxxxxxxxx>
---
.../hwtracing/coresight/coresight-config.h | 5 +-
.../hwtracing/coresight/coresight-etm-perf.c | 164 +++++++++++++++---
.../hwtracing/coresight/coresight-etm-perf.h | 8 +
.../hwtracing/coresight/coresight-syscfg.c | 13 +-
4 files changed, 166 insertions(+), 24 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-config.h b/drivers/hwtracing/coresight/coresight-config.h
index 9d66e0071f38..98380b496046 100644
--- a/drivers/hwtracing/coresight/coresight-config.h
+++ b/drivers/hwtracing/coresight/coresight-config.h
@@ -154,7 +154,8 @@ struct cscfg_config_feat_ref {
* @nr_presets: Number of sets of presets supplied by this configuration.
* @nr_total_params: Sum of all parameters declared by used features
* @presets: Array of preset values.
- *
+ * @id_ea: Extended attribute for perf configid value
+ * @event_ea: Extended attribute for perf event value
*/
struct cscfg_config_desc {
const char *name;
@@ -165,6 +166,8 @@ struct cscfg_config_desc {
int nr_presets;
int nr_total_params;
const u64 *presets; /* nr_presets * nr_total_params */
+ struct dev_ext_attribute *id_ea;
+ struct dev_ext_attribute *event_ea;
};
/**
diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
index a608081bd446..e270bb1e0f7d 100644
--- a/drivers/hwtracing/coresight/coresight-etm-perf.c
+++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
@@ -18,8 +18,10 @@
#include <linux/types.h>
#include <linux/workqueue.h>
+#include "coresight-config.h"
#include "coresight-etm-perf.h"
#include "coresight-priv.h"
+#include "coresight-syscfg.h"
static struct pmu etm_pmu;
static bool etm_perf_up;
@@ -32,8 +34,13 @@ PMU_FORMAT_ATTR(cycacc, "config:" __stringify(ETM_OPT_CYCACC));
PMU_FORMAT_ATTR(contextid, "config:" __stringify(ETM_OPT_CTXTID));
PMU_FORMAT_ATTR(timestamp, "config:" __stringify(ETM_OPT_TS));
PMU_FORMAT_ATTR(retstack, "config:" __stringify(ETM_OPT_RETSTK));
+/* preset - if sink ID is used as a configuration selector */
+PMU_FORMAT_ATTR(preset, "config:0-3");
/* Sink ID - same for all ETMs */
PMU_FORMAT_ATTR(sinkid, "config2:0-31");
+/* config ID - set if a system configuration is selected */
+PMU_FORMAT_ATTR(configid, "config2:32-63");
+
static struct attribute *etm_config_formats_attr[] = {
&format_attr_cycacc.attr,
@@ -41,6 +48,8 @@ static struct attribute *etm_config_formats_attr[] = {
&format_attr_timestamp.attr,
&format_attr_retstack.attr,
&format_attr_sinkid.attr,
+ &format_attr_preset.attr,
+ &format_attr_configid.attr,
NULL,
};
@@ -58,9 +67,29 @@ static const struct attribute_group etm_pmu_sinks_group = {
.attrs = etm_config_sinks_attr,
};
+static struct attribute *etm_config_cscfg_attr[] = {
+ NULL,
+};
+
+static const struct attribute_group etm_pmu_cscfg_group = {
+ .name = "configurations",
+ .attrs = etm_config_cscfg_attr,
+};
+
+static struct attribute *etm_config_events_attr[] = {
+ NULL,
+};
+
+static const struct attribute_group etm_pmu_events_group = {
+ .name = "events",
+ .attrs = etm_config_events_attr,
+};
+
static const struct attribute_group *etm_pmu_attr_groups[] = {
&etm_pmu_format_group,
&etm_pmu_sinks_group,
+ &etm_pmu_cscfg_group,
+ &etm_pmu_events_group,
NULL,
};
@@ -219,7 +248,7 @@ static void *etm_setup_aux(struct perf_event *event, void **pages,
INIT_WORK(&event_data->work, free_event_data);
/* First get the selected sink from user space. */
- if (event->attr.config2) {
+ if (event->attr.config2 & GENMASK_ULL(31, 0)) {
id = (u32)event->attr.config2;
sink = coresight_get_sink_by_id(id);
}
@@ -537,21 +566,17 @@ static ssize_t etm_perf_sink_name_show(struct device *dev,
return scnprintf(buf, PAGE_SIZE, "0x%lx\n", (unsigned long)(ea->var));
}
-int etm_perf_add_symlink_sink(struct coresight_device *csdev)
+int etm_perf_add_symlink_group(struct device *dev,
+ struct dev_ext_attribute **ext_attr,
+ const char *name,
+ const char *group_name)
Couple of nits:
This could be:
struct dev_ext_attribute *
etm_perf_add_to_group_hashed(struct device *dev,
const char *group,
const char *name)
{
}
This could return the ea on success avoiding the **ext_attr as argument.
Also the name of the function indicates what it does.
{
- int ret;
+ struct dev_ext_attribute *ea;
unsigned long hash;
- const char *name;
+ int ret;
struct device *pmu_dev = etm_pmu.dev;
- struct device *dev = &csdev->dev;
- struct dev_ext_attribute *ea;
- if (csdev->type != CORESIGHT_DEV_TYPE_SINK &&
- csdev->type != CORESIGHT_DEV_TYPE_LINKSINK)
- return -EINVAL;
-
- if (csdev->ea != NULL)
- return -EINVAL;
+ *ext_attr = NULL;
if (!etm_perf_up)
return -EPROBE_DEFER;
@@ -560,7 +585,6 @@ int etm_perf_add_symlink_sink(struct coresight_device *csdev)
if (!ea)
return -ENOMEM;
- name = dev_name(dev);
/* See function coresight_get_sink_by_id() to know where this is used */
hash = hashlen_hash(hashlen_string(NULL, name));
@@ -574,31 +598,127 @@ int etm_perf_add_symlink_sink(struct coresight_device *csdev)
ea->var = (unsigned long *)hash;
ret = sysfs_add_file_to_group(&pmu_dev->kobj,
- &ea->attr.attr, "sinks");
-
+ &ea->attr.attr, group_name);
if (!ret)
- csdev->ea = ea;
-
+ *ext_attr = ea;
return ret;
}
-void etm_perf_del_symlink_sink(struct coresight_device *csdev)
+int etm_perf_add_symlink_sink(struct coresight_device *csdev)
+{
+ const char *name;
+ struct device *dev = &csdev->dev;
+
+ if (csdev->type != CORESIGHT_DEV_TYPE_SINK &&
+ csdev->type != CORESIGHT_DEV_TYPE_LINKSINK)
+ return -EINVAL;
+
+ if (csdev->ea != NULL)
+ return -EINVAL;
+
+ name = dev_name(dev);
+ return etm_perf_add_symlink_group(dev, &csdev->ea, name, "sinks");
+}
+
+void etm_perf_del_symlink_group(struct dev_ext_attribute *ea, const char *group_name)
void etm_perf_del_from_group(group, ea)
+/* string to contain the attribute value */
+#define CSCFG_EVENT_STR_SIZE 32
+
+static ssize_t etm_perf_cscfg_event_show(struct device *dev,
+ struct device_attribute *dattr,
+ char *buf)
+{
+ struct dev_ext_attribute *ea;
+
+ ea = container_of(dattr, struct dev_ext_attribute, attr);
+ return scnprintf(buf, PAGE_SIZE, "%s\n", (const char *)(ea->var));
+}
"configid=0x%lx", (unsigned long)ea->var ?
+
+static int etm_perf_add_cscfg_event(struct device *dev, struct cscfg_config_desc *cs_cfg)
+{
+ struct dev_ext_attribute *ea;
+ unsigned long hash;
+ int ret;
+ struct device *pmu_dev = etm_pmu.dev;
+
+ ea = devm_kzalloc(dev, sizeof(*ea), GFP_KERNEL);
+ if (!ea)
+ return -ENOMEM;
+
+ hash = (unsigned long)cs_cfg->id_ea->var;
+
+ sysfs_attr_init(&ea->attr.attr);
+ ea->attr.attr.name = devm_kstrdup(dev, cs_cfg->name, GFP_KERNEL);
+ if (!ea->attr.attr.name)
+ return -ENOMEM;
+
+ /*
+ * attribute value is "configid=<hash>".
+ * this will be what perf evaluates when the config name is used
+ * on the command line.
+ */
+ ea->var = devm_kzalloc(dev, CSCFG_EVENT_STR_SIZE, GFP_KERNEL);
+ if (!ea->var)
+ return -ENOMEM;
Could we drop this string and use the "hash" instead ?
+
+ scnprintf(ea->var, CSCFG_EVENT_STR_SIZE, "configid=0x%lx", hash);
+ ea->attr.attr.mode = 0444;
+ ea->attr.show = etm_perf_cscfg_event_show;
+
+ ret = sysfs_add_file_to_group(&pmu_dev->kobj,
+ &ea->attr.attr, "events");
+ if (!ret)
+ cs_cfg->event_ea = ea;
+ return ret;
+}
+
+int etm_perf_add_symlink_cscfg(struct device *dev, struct cscfg_config_desc *cs_cfg)
etm_perf_add_cscfg() ?
+{
+ int err;
+
+ if (cs_cfg->id_ea != NULL)
+ return 0;
+
+ err = etm_perf_add_symlink_group(dev, &cs_cfg->id_ea,
+ cs_cfg->name, "configurations");
+
+ if (!err)
+ err = etm_perf_add_cscfg_event(dev, cs_cfg);
+
+ return err;
+}
+
+void etm_perf_del_symlink_cscfg(struct cscfg_config_desc *cs_cfg)
etm_perf_del_cscfg() ?
Suzuki