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-rw-r--r--Documentation/trace/coresight/coresight-config.rst78
-rw-r--r--MAINTAINERS1
-rw-r--r--drivers/hwtracing/coresight/coresight-cfg-preload.c9
-rw-r--r--drivers/hwtracing/coresight/coresight-config.h9
-rw-r--r--drivers/hwtracing/coresight/coresight-core.c2
-rw-r--r--drivers/hwtracing/coresight/coresight-etm4x-core.c11
-rw-r--r--drivers/hwtracing/coresight/coresight-stm.c10
-rw-r--r--drivers/hwtracing/coresight/coresight-syscfg-configfs.c87
-rw-r--r--drivers/hwtracing/coresight/coresight-syscfg-configfs.h4
-rw-r--r--drivers/hwtracing/coresight/coresight-syscfg.c315
-rw-r--r--drivers/hwtracing/coresight/coresight-syscfg.h39
-rw-r--r--samples/Kconfig9
-rw-r--r--samples/Makefile1
-rw-r--r--samples/coresight/Makefile4
-rw-r--r--samples/coresight/coresight-cfg-sample.c73
15 files changed, 595 insertions, 57 deletions
diff --git a/Documentation/trace/coresight/coresight-config.rst b/Documentation/trace/coresight/coresight-config.rst
index a4e3ef295240..6d5ffa6f7347 100644
--- a/Documentation/trace/coresight/coresight-config.rst
+++ b/Documentation/trace/coresight/coresight-config.rst
@@ -155,14 +155,14 @@ follows::
autofdo
$ cd autofdo/
$ ls
- description preset1 preset3 preset5 preset7 preset9
- feature_refs preset2 preset4 preset6 preset8
+ description feature_refs preset1 preset3 preset5 preset7 preset9
+ enable preset preset2 preset4 preset6 preset8
$ cat description
Setup ETMs with strobing for autofdo
$ cat feature_refs
strobing
-Each preset declared has a preset<n> subdirectory declared. The values for
+Each preset declared has a 'preset<n>' subdirectory declared. The values for
the preset can be examined::
$ cat preset1/values
@@ -170,6 +170,9 @@ the preset can be examined::
$ cat preset2/values
strobing.window = 0x1388 strobing.period = 0x4
+The 'enable' and 'preset' files allow the control of a configuration when
+using CoreSight with sysfs.
+
The features referenced by the configuration can be examined in the features
directory::
@@ -211,19 +214,13 @@ also declared in the perf 'cs_etm' event infrastructure so that they can
be selected when running trace under perf::
$ ls /sys/devices/cs_etm
- configurations format perf_event_mux_interval_ms sinks type
- events nr_addr_filters power
-
-Key directories here are 'configurations' - which lists the loaded
-configurations, and 'events' - a generic perf directory which allows
-selection on the perf command line.::
+ cpu0 cpu2 events nr_addr_filters power subsystem uevent
+ cpu1 cpu3 format perf_event_mux_interval_ms sinks type
- $ ls configurations/
- autofdo
- $ cat configurations/autofdo
- 0xa7c3dddd
+The key directory here is 'events' - a generic perf directory which allows
+selection on the perf command line. As with the sinks entries, this provides
+a hash of the configuration name.
-As with the sinks entries, this provides a hash of the configuration name.
The entry in the 'events' directory uses perfs built in syntax generator
to substitute the syntax for the name when evaluating the command::
@@ -242,3 +239,56 @@ A preset to override the current parameter values can also be selected::
When configurations are selected in this way, then the trace sink used is
automatically selected.
+
+Using Configurations in sysfs
+=============================
+
+Coresight can be controlled using sysfs. When this is in use then a configuration
+can be made active for the devices that are used in the sysfs session.
+
+In a configuration there are 'enable' and 'preset' files.
+
+To enable a configuration for use with sysfs::
+
+ $ cd configurations/autofdo
+ $ echo 1 > enable
+
+This will then use any default parameter values in the features - which can be
+adjusted as described above.
+
+To use a preset<n> set of parameter values::
+
+ $ echo 3 > preset
+
+This will select preset3 for the configuration.
+The valid values for preset are 0 - to deselect presets, and any value of
+<n> where a preset<n> sub-directory is present.
+
+Note that the active sysfs configuration is a global parameter, therefore
+only a single configuration can be active for sysfs at any one time.
+Attempting to enable a second configuration will result in an error.
+Additionally, attempting to disable the configuration while in use will
+also result in an error.
+
+The use of the active configuration by sysfs is independent of the configuration
+used in perf.
+
+
+Creating and Loading Custom Configurations
+==========================================
+
+Custom configurations and / or features can be dynamically loaded into the
+system by using a loadable module.
+
+An example of a custom configuration is found in ./samples/coresight.
+
+This creates a new configuration that uses the existing built in
+strobing feature, but provides a different set of presets.
+
+When the module is loaded, then the configuration appears in the configfs
+file system and is selectable in the same way as the built in configuration
+described above.
+
+Configurations can use previously loaded features. The system will ensure
+that it is not possible to unload a feature that is currently in use, by
+enforcing the unload order as the strict reverse of the load order.
diff --git a/MAINTAINERS b/MAINTAINERS
index 5f040a502859..5ed02283e0fc 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1890,6 +1890,7 @@ F: Documentation/trace/coresight/*
F: drivers/hwtracing/coresight/*
F: include/dt-bindings/arm/coresight-cti-dt.h
F: include/linux/coresight*
+F: samples/coresight/*
F: tools/perf/arch/arm/util/auxtrace.c
F: tools/perf/arch/arm/util/cs-etm.c
F: tools/perf/arch/arm/util/cs-etm.h
diff --git a/drivers/hwtracing/coresight/coresight-cfg-preload.c b/drivers/hwtracing/coresight/coresight-cfg-preload.c
index 751af3710d56..e237a4edfa09 100644
--- a/drivers/hwtracing/coresight/coresight-cfg-preload.c
+++ b/drivers/hwtracing/coresight/coresight-cfg-preload.c
@@ -24,8 +24,13 @@ static struct cscfg_config_desc *preload_cfgs[] = {
NULL
};
+static struct cscfg_load_owner_info preload_owner = {
+ .type = CSCFG_OWNER_PRELOAD,
+};
+
/* preload called on initialisation */
-int cscfg_preload(void)
+int cscfg_preload(void *owner_handle)
{
- return cscfg_load_config_sets(preload_cfgs, preload_feats);
+ preload_owner.owner_handle = owner_handle;
+ return cscfg_load_config_sets(preload_cfgs, preload_feats, &preload_owner);
}
diff --git a/drivers/hwtracing/coresight/coresight-config.h b/drivers/hwtracing/coresight/coresight-config.h
index 25eb6c632692..9bd44b940add 100644
--- a/drivers/hwtracing/coresight/coresight-config.h
+++ b/drivers/hwtracing/coresight/coresight-config.h
@@ -97,6 +97,8 @@ struct cscfg_regval_desc {
* @params_desc: array of parameters used.
* @nr_regs: number of registers used.
* @regs_desc: array of registers used.
+ * @load_owner: handle to load owner for dynamic load and unload of features.
+ * @fs_group: reference to configfs group for dynamic unload.
*/
struct cscfg_feature_desc {
const char *name;
@@ -107,6 +109,8 @@ struct cscfg_feature_desc {
struct cscfg_parameter_desc *params_desc;
int nr_regs;
struct cscfg_regval_desc *regs_desc;
+ void *load_owner;
+ struct config_group *fs_group;
};
/**
@@ -128,7 +132,8 @@ struct cscfg_feature_desc {
* @presets: Array of preset values.
* @event_ea: Extended attribute for perf event value
* @active_cnt: ref count for activate on this configuration.
- *
+ * @load_owner: handle to load owner for dynamic load and unload of configs.
+ * @fs_group: reference to configfs group for dynamic unload.
*/
struct cscfg_config_desc {
const char *name;
@@ -141,6 +146,8 @@ struct cscfg_config_desc {
const u64 *presets; /* nr_presets * nr_total_params */
struct dev_ext_attribute *event_ea;
atomic_t active_cnt;
+ void *load_owner;
+ struct config_group *fs_group;
};
/**
diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c
index 8a18c71df37a..88653d1c06a4 100644
--- a/drivers/hwtracing/coresight/coresight-core.c
+++ b/drivers/hwtracing/coresight/coresight-core.c
@@ -729,7 +729,7 @@ static inline void coresight_put_ref(struct coresight_device *csdev)
* coresight_grab_device - Power up this device and any of the helper
* devices connected to it for trace operation. Since the helper devices
* don't appear on the trace path, they should be handled along with the
- * the master device.
+ * master device.
*/
static int coresight_grab_device(struct coresight_device *csdev)
{
diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
index 86a313857b58..bf18128cf5de 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
@@ -722,7 +722,16 @@ static int etm4_enable_sysfs(struct coresight_device *csdev)
{
struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
struct etm4_enable_arg arg = { };
- int ret;
+ unsigned long cfg_hash;
+ int ret, preset;
+
+ /* enable any config activated by configfs */
+ cscfg_config_sysfs_get_active_cfg(&cfg_hash, &preset);
+ if (cfg_hash) {
+ ret = cscfg_csdev_enable_active_config(csdev, cfg_hash, preset);
+ if (ret)
+ return ret;
+ }
spin_lock(&drvdata->spinlock);
diff --git a/drivers/hwtracing/coresight/coresight-stm.c b/drivers/hwtracing/coresight/coresight-stm.c
index 58062a5a8238..bb14a3a8a921 100644
--- a/drivers/hwtracing/coresight/coresight-stm.c
+++ b/drivers/hwtracing/coresight/coresight-stm.c
@@ -856,13 +856,11 @@ static int stm_probe(struct amba_device *adev, const struct amba_id *id)
{
int ret;
void __iomem *base;
- unsigned long *guaranteed;
struct device *dev = &adev->dev;
struct coresight_platform_data *pdata = NULL;
struct stm_drvdata *drvdata;
struct resource *res = &adev->res;
struct resource ch_res;
- size_t bitmap_size;
struct coresight_desc desc = { 0 };
desc.name = coresight_alloc_device_name(&stm_devs, dev);
@@ -904,12 +902,10 @@ static int stm_probe(struct amba_device *adev, const struct amba_id *id)
else
drvdata->numsp = stm_num_stimulus_port(drvdata);
- bitmap_size = BITS_TO_LONGS(drvdata->numsp) * sizeof(long);
-
- guaranteed = devm_kzalloc(dev, bitmap_size, GFP_KERNEL);
- if (!guaranteed)
+ drvdata->chs.guaranteed = devm_bitmap_zalloc(dev, drvdata->numsp,
+ GFP_KERNEL);
+ if (!drvdata->chs.guaranteed)
return -ENOMEM;
- drvdata->chs.guaranteed = guaranteed;
spin_lock_init(&drvdata->spinlock);
diff --git a/drivers/hwtracing/coresight/coresight-syscfg-configfs.c b/drivers/hwtracing/coresight/coresight-syscfg-configfs.c
index c547816b9000..433ede94dd63 100644
--- a/drivers/hwtracing/coresight/coresight-syscfg-configfs.c
+++ b/drivers/hwtracing/coresight/coresight-syscfg-configfs.c
@@ -6,6 +6,7 @@
#include <linux/configfs.h>
+#include "coresight-config.h"
#include "coresight-syscfg-configfs.h"
/* create a default ci_type. */
@@ -87,9 +88,75 @@ static ssize_t cscfg_cfg_values_show(struct config_item *item, char *page)
}
CONFIGFS_ATTR_RO(cscfg_cfg_, values);
+static ssize_t cscfg_cfg_enable_show(struct config_item *item, char *page)
+{
+ struct cscfg_fs_config *fs_config = container_of(to_config_group(item),
+ struct cscfg_fs_config, group);
+
+ return scnprintf(page, PAGE_SIZE, "%d\n", fs_config->active);
+}
+
+static ssize_t cscfg_cfg_enable_store(struct config_item *item,
+ const char *page, size_t count)
+{
+ struct cscfg_fs_config *fs_config = container_of(to_config_group(item),
+ struct cscfg_fs_config, group);
+ int err;
+ bool val;
+
+ err = kstrtobool(page, &val);
+ if (!err)
+ err = cscfg_config_sysfs_activate(fs_config->config_desc, val);
+ if (!err) {
+ fs_config->active = val;
+ if (val)
+ cscfg_config_sysfs_set_preset(fs_config->preset);
+ }
+ return err ? err : count;
+}
+CONFIGFS_ATTR(cscfg_cfg_, enable);
+
+static ssize_t cscfg_cfg_preset_show(struct config_item *item, char *page)
+{
+ struct cscfg_fs_config *fs_config = container_of(to_config_group(item),
+ struct cscfg_fs_config, group);
+
+ return scnprintf(page, PAGE_SIZE, "%d\n", fs_config->preset);
+}
+
+static ssize_t cscfg_cfg_preset_store(struct config_item *item,
+ const char *page, size_t count)
+{
+ struct cscfg_fs_config *fs_config = container_of(to_config_group(item),
+ struct cscfg_fs_config, group);
+ int preset, err;
+
+ err = kstrtoint(page, 0, &preset);
+ if (!err) {
+ /*
+ * presets start at 1, and go up to max (15),
+ * but the config may provide fewer.
+ */
+ if ((preset < 1) || (preset > fs_config->config_desc->nr_presets))
+ err = -EINVAL;
+ }
+
+ if (!err) {
+ /* set new value */
+ fs_config->preset = preset;
+ /* set on system if active */
+ if (fs_config->active)
+ cscfg_config_sysfs_set_preset(fs_config->preset);
+ }
+ return err ? err : count;
+}
+CONFIGFS_ATTR(cscfg_cfg_, preset);
+
static struct configfs_attribute *cscfg_config_view_attrs[] = {
&cscfg_cfg_attr_description,
&cscfg_cfg_attr_feature_refs,
+ &cscfg_cfg_attr_enable,
+ &cscfg_cfg_attr_preset,
NULL,
};
@@ -334,9 +401,19 @@ int cscfg_configfs_add_config(struct cscfg_config_desc *config_desc)
if (IS_ERR(new_group))
return PTR_ERR(new_group);
err = configfs_register_group(&cscfg_configs_grp, new_group);
+ if (!err)
+ config_desc->fs_group = new_group;
return err;
}
+void cscfg_configfs_del_config(struct cscfg_config_desc *config_desc)
+{
+ if (config_desc->fs_group) {
+ configfs_unregister_group(config_desc->fs_group);
+ config_desc->fs_group = NULL;
+ }
+}
+
static struct config_item_type cscfg_features_type = {
.ct_owner = THIS_MODULE,
};
@@ -358,9 +435,19 @@ int cscfg_configfs_add_feature(struct cscfg_feature_desc *feat_desc)
if (IS_ERR(new_group))
return PTR_ERR(new_group);
err = configfs_register_group(&cscfg_features_grp, new_group);
+ if (!err)
+ feat_desc->fs_group = new_group;
return err;
}
+void cscfg_configfs_del_feature(struct cscfg_feature_desc *feat_desc)
+{
+ if (feat_desc->fs_group) {
+ configfs_unregister_group(feat_desc->fs_group);
+ feat_desc->fs_group = NULL;
+ }
+}
+
int cscfg_configfs_init(struct cscfg_manager *cscfg_mgr)
{
struct configfs_subsystem *subsys;
diff --git a/drivers/hwtracing/coresight/coresight-syscfg-configfs.h b/drivers/hwtracing/coresight/coresight-syscfg-configfs.h
index 7d6ffe35ca4c..373d84d43268 100644
--- a/drivers/hwtracing/coresight/coresight-syscfg-configfs.h
+++ b/drivers/hwtracing/coresight/coresight-syscfg-configfs.h
@@ -15,6 +15,8 @@
struct cscfg_fs_config {
struct cscfg_config_desc *config_desc;
struct config_group group;
+ bool active;
+ int preset;
};
/* container for feature view */
@@ -41,5 +43,7 @@ int cscfg_configfs_init(struct cscfg_manager *cscfg_mgr);
void cscfg_configfs_release(struct cscfg_manager *cscfg_mgr);
int cscfg_configfs_add_config(struct cscfg_config_desc *config_desc);
int cscfg_configfs_add_feature(struct cscfg_feature_desc *feat_desc);
+void cscfg_configfs_del_config(struct cscfg_config_desc *config_desc);
+void cscfg_configfs_del_feature(struct cscfg_feature_desc *feat_desc);
#endif /* CORESIGHT_SYSCFG_CONFIGFS_H */
diff --git a/drivers/hwtracing/coresight/coresight-syscfg.c b/drivers/hwtracing/coresight/coresight-syscfg.c
index 43054568430f..098fc34c4829 100644
--- a/drivers/hwtracing/coresight/coresight-syscfg.c
+++ b/drivers/hwtracing/coresight/coresight-syscfg.c
@@ -250,6 +250,13 @@ static int cscfg_check_feat_for_cfg(struct cscfg_config_desc *config_desc)
static int cscfg_load_feat(struct cscfg_feature_desc *feat_desc)
{
int err;
+ struct cscfg_feature_desc *feat_desc_exist;
+
+ /* new feature must have unique name */
+ list_for_each_entry(feat_desc_exist, &cscfg_mgr->feat_desc_list, item) {
+ if (!strcmp(feat_desc_exist->name, feat_desc->name))
+ return -EEXIST;
+ }
/* add feature to any matching registered devices */
err = cscfg_add_feat_to_csdevs(feat_desc);
@@ -267,6 +274,13 @@ static int cscfg_load_feat(struct cscfg_feature_desc *feat_desc)
static int cscfg_load_config(struct cscfg_config_desc *config_desc)
{
int err;
+ struct cscfg_config_desc *config_desc_exist;
+
+ /* new configuration must have a unique name */
+ list_for_each_entry(config_desc_exist, &cscfg_mgr->config_desc_list, item) {
+ if (!strcmp(config_desc_exist->name, config_desc->name))
+ return -EEXIST;
+ }
/* validate features are present */
err = cscfg_check_feat_for_cfg(config_desc);
@@ -354,6 +368,92 @@ unlock_exit:
return err;
}
+/*
+ * Conditionally up reference count on owner to prevent unload.
+ *
+ * module loaded configs need to be locked in to prevent premature unload.
+ */
+static int cscfg_owner_get(struct cscfg_load_owner_info *owner_info)
+{
+ if ((owner_info->type == CSCFG_OWNER_MODULE) &&
+ (!try_module_get(owner_info->owner_handle)))
+ return -EINVAL;
+ return 0;
+}
+
+/* conditionally lower ref count on an owner */
+static void cscfg_owner_put(struct cscfg_load_owner_info *owner_info)
+{
+ if (owner_info->type == CSCFG_OWNER_MODULE)
+ module_put(owner_info->owner_handle);
+}
+
+static void cscfg_remove_owned_csdev_configs(struct coresight_device *csdev, void *load_owner)
+{
+ struct cscfg_config_csdev *config_csdev, *tmp;
+
+ if (list_empty(&csdev->config_csdev_list))
+ return;
+
+ list_for_each_entry_safe(config_csdev, tmp, &csdev->config_csdev_list, node) {
+ if (config_csdev->config_desc->load_owner == load_owner)
+ list_del(&config_csdev->node);
+ }
+}
+
+static void cscfg_remove_owned_csdev_features(struct coresight_device *csdev, void *load_owner)
+{
+ struct cscfg_feature_csdev *feat_csdev, *tmp;
+
+ if (list_empty(&csdev->feature_csdev_list))
+ return;
+
+ list_for_each_entry_safe(feat_csdev, tmp, &csdev->feature_csdev_list, node) {
+ if (feat_csdev->feat_desc->load_owner == load_owner)
+ list_del(&feat_csdev->node);
+ }
+}
+
+/*
+ * removal is relatively easy - just remove from all lists, anything that
+ * matches the owner. Memory for the descriptors will be managed by the owner,
+ * memory for the csdev items is devm_ allocated with the individual csdev
+ * devices.
+ */
+static void cscfg_unload_owned_cfgs_feats(void *load_owner)
+{
+ struct cscfg_config_desc *config_desc, *cfg_tmp;
+ struct cscfg_feature_desc *feat_desc, *feat_tmp;
+ struct cscfg_registered_csdev *csdev_item;
+
+ /* remove from each csdev instance feature and config lists */
+ list_for_each_entry(csdev_item, &cscfg_mgr->csdev_desc_list, item) {
+ /*
+ * for each csdev, check the loaded lists and remove if
+ * referenced descriptor is owned
+ */
+ cscfg_remove_owned_csdev_configs(csdev_item->csdev, load_owner);
+ cscfg_remove_owned_csdev_features(csdev_item->csdev, load_owner);
+ }
+
+ /* remove from the config descriptor lists */
+ list_for_each_entry_safe(config_desc, cfg_tmp, &cscfg_mgr->config_desc_list, item) {
+ if (config_desc->load_owner == load_owner) {
+ cscfg_configfs_del_config(config_desc);
+ etm_perf_del_symlink_cscfg(config_desc);
+ list_del(&config_desc->item);
+ }
+ }
+
+ /* remove from the feature descriptor lists */
+ list_for_each_entry_safe(feat_desc, feat_tmp, &cscfg_mgr->feat_desc_list, item) {
+ if (feat_desc->load_owner == load_owner) {
+ cscfg_configfs_del_feature(feat_desc);
+ list_del(&feat_desc->item);
+ }
+ }
+}
+
/**
* cscfg_load_config_sets - API function to load feature and config sets.
*
@@ -361,13 +461,22 @@ unlock_exit:
* descriptors and load into the system.
* Features are loaded first to ensure configuration dependencies can be met.
*
+ * To facilitate dynamic loading and unloading, features and configurations
+ * have a "load_owner", to allow later unload by the same owner. An owner may
+ * be a loadable module or configuration dynamically created via configfs.
+ * As later loaded configurations can use earlier loaded features, creating load
+ * dependencies, a load order list is maintained. Unload is strictly in the
+ * reverse order to load.
+ *
* @config_descs: 0 terminated array of configuration descriptors.
* @feat_descs: 0 terminated array of feature descriptors.
+ * @owner_info: Information on the owner of this set.
*/
int cscfg_load_config_sets(struct cscfg_config_desc **config_descs,
- struct cscfg_feature_desc **feat_descs)
+ struct cscfg_feature_desc **feat_descs,
+ struct cscfg_load_owner_info *owner_info)
{
- int err, i = 0;
+ int err = 0, i = 0;
mutex_lock(&cscfg_mutex);
@@ -380,8 +489,10 @@ int cscfg_load_config_sets(struct cscfg_config_desc **config_descs,
if (err) {
pr_err("coresight-syscfg: Failed to load feature %s\n",
feat_descs[i]->name);
+ cscfg_unload_owned_cfgs_feats(owner_info);
goto exit_unlock;
}
+ feat_descs[i]->load_owner = owner_info;
i++;
}
}
@@ -396,18 +507,86 @@ int cscfg_load_config_sets(struct cscfg_config_desc **config_descs,
if (err) {
pr_err("coresight-syscfg: Failed to load configuration %s\n",
config_descs[i]->name);
+ cscfg_unload_owned_cfgs_feats(owner_info);
goto exit_unlock;
}
+ config_descs[i]->load_owner = owner_info;
i++;
}
}
+ /* add the load owner to the load order list */
+ list_add_tail(&owner_info->item, &cscfg_mgr->load_order_list);
+ if (!list_is_singular(&cscfg_mgr->load_order_list)) {
+ /* lock previous item in load order list */
+ err = cscfg_owner_get(list_prev_entry(owner_info, item));
+ if (err) {
+ cscfg_unload_owned_cfgs_feats(owner_info);
+ list_del(&owner_info->item);
+ }
+ }
+
exit_unlock:
mutex_unlock(&cscfg_mutex);
return err;
}
EXPORT_SYMBOL_GPL(cscfg_load_config_sets);
+/**
+ * cscfg_unload_config_sets - unload a set of configurations by owner.
+ *
+ * Dynamic unload of configuration and feature sets is done on the basis of
+ * the load owner of that set. Later loaded configurations can depend on
+ * features loaded earlier.
+ *
+ * Therefore, unload is only possible if:-
+ * 1) no configurations are active.
+ * 2) the set being unloaded was the last to be loaded to maintain dependencies.
+ *
+ * @owner_info: Information on owner for set being unloaded.
+ */
+int cscfg_unload_config_sets(struct cscfg_load_owner_info *owner_info)
+{
+ int err = 0;
+ struct cscfg_load_owner_info *load_list_item = NULL;
+
+ mutex_lock(&cscfg_mutex);
+
+ /* cannot unload if anything is active */
+ if (atomic_read(&cscfg_mgr->sys_active_cnt)) {
+ err = -EBUSY;
+ goto exit_unlock;
+ }
+
+ /* cannot unload if not last loaded in load order */
+ if (!list_empty(&cscfg_mgr->load_order_list)) {
+ load_list_item = list_last_entry(&cscfg_mgr->load_order_list,
+ struct cscfg_load_owner_info, item);
+ if (load_list_item != owner_info)
+ load_list_item = NULL;
+ }
+
+ if (!load_list_item) {
+ err = -EINVAL;
+ goto exit_unlock;
+ }
+
+ /* unload all belonging to load_owner */
+ cscfg_unload_owned_cfgs_feats(owner_info);
+
+ /* remove from load order list */
+ if (!list_is_singular(&cscfg_mgr->load_order_list)) {
+ /* unlock previous item in load order list */
+ cscfg_owner_put(list_prev_entry(owner_info, item));
+ }
+ list_del(&owner_info->item);
+
+exit_unlock:
+ mutex_unlock(&cscfg_mutex);
+ return err;
+}
+EXPORT_SYMBOL_GPL(cscfg_unload_config_sets);
+
/* Handle coresight device registration and add configs and features to devices */
/* iterate through config lists and load matching configs to device */
@@ -566,32 +745,26 @@ unlock_exit:
}
EXPORT_SYMBOL_GPL(cscfg_csdev_reset_feats);
-/**
- * cscfg_activate_config - Mark a configuration descriptor as active.
- *
- * This will be seen when csdev devices are enabled in the system.
- * Only activated configurations can be enabled on individual devices.
- * Activation protects the configuration from alteration or removal while
- * active.
- *
- * Selection by hash value - generated from the configuration name when it
- * was loaded and added to the cs_etm/configurations file system for selection
- * by perf.
+/*
+ * This activate configuration for either perf or sysfs. Perf can have multiple
+ * active configs, selected per event, sysfs is limited to one.
*
* Increments the configuration descriptor active count and the global active
* count.
*
* @cfg_hash: Hash value of the selected configuration name.
*/
-int cscfg_activate_config(unsigned long cfg_hash)
+static int _cscfg_activate_config(unsigned long cfg_hash)
{
struct cscfg_config_desc *config_desc;
int err = -EINVAL;
- mutex_lock(&cscfg_mutex);
-
list_for_each_entry(config_desc, &cscfg_mgr->config_desc_list, item) {
if ((unsigned long)config_desc->event_ea->var == cfg_hash) {
+ /* must ensure that config cannot be unloaded in use */
+ err = cscfg_owner_get(config_desc->load_owner);
+ if (err)
+ break;
/*
* increment the global active count - control changes to
* active configurations
@@ -609,6 +782,101 @@ int cscfg_activate_config(unsigned long cfg_hash)
break;
}
}
+ return err;
+}
+
+static void _cscfg_deactivate_config(unsigned long cfg_hash)
+{
+ struct cscfg_config_desc *config_desc;
+
+ list_for_each_entry(config_desc, &cscfg_mgr->config_desc_list, item) {
+ if ((unsigned long)config_desc->event_ea->var == cfg_hash) {
+ atomic_dec(&config_desc->active_cnt);
+ atomic_dec(&cscfg_mgr->sys_active_cnt);
+ cscfg_owner_put(config_desc->load_owner);
+ dev_dbg(cscfg_device(), "Deactivate config %s.\n", config_desc->name);
+ break;
+ }
+ }
+}
+
+/*
+ * called from configfs to set/clear the active configuration for use when
+ * using sysfs to control trace.
+ */
+int cscfg_config_sysfs_activate(struct cscfg_config_desc *config_desc, bool activate)
+{
+ unsigned long cfg_hash;
+ int err = 0;
+
+ mutex_lock(&cscfg_mutex);
+
+ cfg_hash = (unsigned long)config_desc->event_ea->var;
+
+ if (activate) {
+ /* cannot be a current active value to activate this */
+ if (cscfg_mgr->sysfs_active_config) {
+ err = -EBUSY;
+ goto exit_unlock;
+ }
+ err = _cscfg_activate_config(cfg_hash);
+ if (!err)
+ cscfg_mgr->sysfs_active_config = cfg_hash;
+ } else {
+ /* disable if matching current value */
+ if (cscfg_mgr->sysfs_active_config == cfg_hash) {
+ _cscfg_deactivate_config(cfg_hash);
+ cscfg_mgr->sysfs_active_config = 0;
+ } else
+ err = -EINVAL;
+ }
+
+exit_unlock:
+ mutex_unlock(&cscfg_mutex);
+ return err;
+}
+
+/* set the sysfs preset value */
+void cscfg_config_sysfs_set_preset(int preset)
+{
+ mutex_lock(&cscfg_mutex);
+ cscfg_mgr->sysfs_active_preset = preset;
+ mutex_unlock(&cscfg_mutex);
+}
+
+/*
+ * Used by a device to get the config and preset selected as active in configfs,
+ * when using sysfs to control trace.
+ */
+void cscfg_config_sysfs_get_active_cfg(unsigned long *cfg_hash, int *preset)
+{
+ mutex_lock(&cscfg_mutex);
+ *preset = cscfg_mgr->sysfs_active_preset;
+ *cfg_hash = cscfg_mgr->sysfs_active_config;
+ mutex_unlock(&cscfg_mutex);
+}
+EXPORT_SYMBOL_GPL(cscfg_config_sysfs_get_active_cfg);
+
+/**
+ * cscfg_activate_config - Mark a configuration descriptor as active.
+ *
+ * This will be seen when csdev devices are enabled in the system.
+ * Only activated configurations can be enabled on individual devices.
+ * Activation protects the configuration from alteration or removal while
+ * active.
+ *
+ * Selection by hash value - generated from the configuration name when it
+ * was loaded and added to the cs_etm/configurations file system for selection
+ * by perf.
+ *
+ * @cfg_hash: Hash value of the selected configuration name.
+ */
+int cscfg_activate_config(unsigned long cfg_hash)
+{
+ int err = 0;
+
+ mutex_lock(&cscfg_mutex);
+ err = _cscfg_activate_config(cfg_hash);
mutex_unlock(&cscfg_mutex);
return err;
@@ -624,18 +892,8 @@ EXPORT_SYMBOL_GPL(cscfg_activate_config);
*/
void cscfg_deactivate_config(unsigned long cfg_hash)
{
- struct cscfg_config_desc *config_desc;
-
mutex_lock(&cscfg_mutex);
-
- list_for_each_entry(config_desc, &cscfg_mgr->config_desc_list, item) {
- if ((unsigned long)config_desc->event_ea->var == cfg_hash) {
- atomic_dec(&config_desc->active_cnt);
- atomic_dec(&cscfg_mgr->sys_active_cnt);
- dev_dbg(cscfg_device(), "Deactivate config %s.\n", config_desc->name);
- break;
- }
- }
+ _cscfg_deactivate_config(cfg_hash);
mutex_unlock(&cscfg_mutex);
}
EXPORT_SYMBOL_GPL(cscfg_deactivate_config);
@@ -827,10 +1085,11 @@ int __init cscfg_init(void)
INIT_LIST_HEAD(&cscfg_mgr->csdev_desc_list);
INIT_LIST_HEAD(&cscfg_mgr->feat_desc_list);
INIT_LIST_HEAD(&cscfg_mgr->config_desc_list);
+ INIT_LIST_HEAD(&cscfg_mgr->load_order_list);
atomic_set(&cscfg_mgr->sys_active_cnt, 0);
/* preload built-in configurations */
- err = cscfg_preload();
+ err = cscfg_preload(THIS_MODULE);
if (err)
goto exit_err;
diff --git a/drivers/hwtracing/coresight/coresight-syscfg.h b/drivers/hwtracing/coresight/coresight-syscfg.h
index 8d018efd6ead..9106ffab4833 100644
--- a/drivers/hwtracing/coresight/coresight-syscfg.h
+++ b/drivers/hwtracing/coresight/coresight-syscfg.h
@@ -25,16 +25,22 @@
* @csdev_desc_list: List of coresight devices registered with the configuration manager.
* @feat_desc_list: List of feature descriptors to load into registered devices.
* @config_desc_list: List of system configuration descriptors to load into registered devices.
+ * @load_order_list: Ordered list of owners for dynamically loaded configurations.
* @sys_active_cnt: Total number of active config descriptor references.
* @cfgfs_subsys: configfs subsystem used to manage configurations.
+ * @sysfs_active_config:Active config hash used if CoreSight controlled from sysfs.
+ * @sysfs_active_preset:Active preset index used if CoreSight controlled from sysfs.
*/
struct cscfg_manager {
struct device dev;
struct list_head csdev_desc_list;
struct list_head feat_desc_list;
struct list_head config_desc_list;
+ struct list_head load_order_list;
atomic_t sys_active_cnt;
struct configfs_subsystem cfgfs_subsys;
+ u32 sysfs_active_config;
+ int sysfs_active_preset;
};
/* get reference to dev in cscfg_manager */
@@ -56,18 +62,44 @@ struct cscfg_registered_csdev {
struct list_head item;
};
+/* owner types for loading and unloading of config and feature sets */
+enum cscfg_load_owner_type {
+ CSCFG_OWNER_PRELOAD,
+ CSCFG_OWNER_MODULE,
+};
+
+/**
+ * Load item - item to add to the load order list allowing dynamic load and
+ * unload of configurations and features. Caller loading a config
+ * set provides a context handle for unload. API ensures that
+ * items unloaded strictly in reverse order from load to ensure
+ * dependencies are respected.
+ *
+ * @item: list entry for load order list.
+ * @type: type of owner - allows interpretation of owner_handle.
+ * @owner_handle: load context - handle for owner of loaded configs.
+ */
+struct cscfg_load_owner_info {
+ struct list_head item;
+ int type;
+ void *owner_handle;
+};
+
/* internal core operations for cscfg */
int __init cscfg_init(void);
void cscfg_exit(void);
-int cscfg_preload(void);
+int cscfg_preload(void *owner_handle);
const struct cscfg_feature_desc *cscfg_get_named_feat_desc(const char *name);
int cscfg_update_feat_param_val(struct cscfg_feature_desc *feat_desc,
int param_idx, u64 value);
-
+int cscfg_config_sysfs_activate(struct cscfg_config_desc *cfg_desc, bool activate);
+void cscfg_config_sysfs_set_preset(int preset);
/* syscfg manager external API */
int cscfg_load_config_sets(struct cscfg_config_desc **cfg_descs,
- struct cscfg_feature_desc **feat_descs);
+ struct cscfg_feature_desc **feat_descs,
+ struct cscfg_load_owner_info *owner_info);
+int cscfg_unload_config_sets(struct cscfg_load_owner_info *owner_info);
int cscfg_register_csdev(struct coresight_device *csdev, u32 match_flags,
struct cscfg_csdev_feat_ops *ops);
void cscfg_unregister_csdev(struct coresight_device *csdev);
@@ -77,5 +109,6 @@ void cscfg_csdev_reset_feats(struct coresight_device *csdev);
int cscfg_csdev_enable_active_config(struct coresight_device *csdev,
unsigned long cfg_hash, int preset);
void cscfg_csdev_disable_active_config(struct coresight_device *csdev);
+void cscfg_config_sysfs_get_active_cfg(unsigned long *cfg_hash, int *preset);
#endif /* CORESIGHT_SYSCFG_H */
diff --git a/samples/Kconfig b/samples/Kconfig
index 43d2e9aa557f..22cc921ae291 100644
--- a/samples/Kconfig
+++ b/samples/Kconfig
@@ -241,6 +241,15 @@ config SAMPLE_WATCH_QUEUE
Build example userspace program to use the new mount_notify(),
sb_notify() syscalls and the KEYCTL_WATCH_KEY keyctl() function.
+config SAMPLE_CORESIGHT_SYSCFG
+ tristate "Build example loadable module for CoreSight config"
+ depends on CORESIGHT && m
+ help
+ Build an example loadable module that adds new CoreSight features
+ and configuration using the CoreSight system configuration API.
+ This demonstrates how a user may create their own CoreSight
+ configurations and easily load them into the system at runtime.
+
endif # SAMPLES
config HAVE_SAMPLE_FTRACE_DIRECT
diff --git a/samples/Makefile b/samples/Makefile
index 4bcd6b93bffa..1ae4de99c983 100644
--- a/samples/Makefile
+++ b/samples/Makefile
@@ -32,3 +32,4 @@ obj-$(CONFIG_SAMPLE_INTEL_MEI) += mei/
subdir-$(CONFIG_SAMPLE_WATCHDOG) += watchdog
subdir-$(CONFIG_SAMPLE_WATCH_QUEUE) += watch_queue
obj-$(CONFIG_DEBUG_KMEMLEAK_TEST) += kmemleak/
+obj-$(CONFIG_SAMPLE_CORESIGHT_SYSCFG) += coresight/
diff --git a/samples/coresight/Makefile b/samples/coresight/Makefile
new file mode 100644
index 000000000000..b3fce4af2347
--- /dev/null
+++ b/samples/coresight/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+obj-$(CONFIG_SAMPLE_CORESIGHT_SYSCFG) += coresight-cfg-sample.o
+ccflags-y += -I$(srctree)/drivers/hwtracing/coresight
diff --git a/samples/coresight/coresight-cfg-sample.c b/samples/coresight/coresight-cfg-sample.c
new file mode 100644
index 000000000000..25485c80b5e3
--- /dev/null
+++ b/samples/coresight/coresight-cfg-sample.c
@@ -0,0 +1,73 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright(C) 2020 Linaro Limited. All rights reserved.
+ * Author: Mike Leach <mike.leach@linaro.org>
+ */
+
+#include "coresight-config.h"
+#include "coresight-syscfg.h"
+
+/* create an alternate autofdo configuration */
+
+/* we will provide 4 sets of preset parameter values */
+#define AFDO2_NR_PRESETS 4
+/* the total number of parameters in used features - strobing has 2 */
+#define AFDO2_NR_PARAM_SUM 2
+
+static const char *afdo2_ref_names[] = {
+ "strobing",
+};
+
+/*
+ * set of presets leaves strobing window constant while varying period to allow
+ * experimentation with mark / space ratios for various workloads
+ */
+static u64 afdo2_presets[AFDO2_NR_PRESETS][AFDO2_NR_PARAM_SUM] = {
+ { 1000, 100 },
+ { 1000, 1000 },
+ { 1000, 5000 },
+ { 1000, 10000 },
+};
+
+struct cscfg_config_desc afdo2 = {
+ .name = "autofdo2",
+ .description = "Setup ETMs with strobing for autofdo\n"
+ "Supplied presets allow experimentation with mark-space ratio for various loads\n",
+ .nr_feat_refs = ARRAY_SIZE(afdo2_ref_names),
+ .feat_ref_names = afdo2_ref_names,
+ .nr_presets = AFDO2_NR_PRESETS,
+ .nr_total_params = AFDO2_NR_PARAM_SUM,
+ .presets = &afdo2_presets[0][0],
+};
+
+static struct cscfg_feature_desc *sample_feats[] = {
+ NULL
+};
+
+static struct cscfg_config_desc *sample_cfgs[] = {
+ &afdo2,
+ NULL
+};
+
+static struct cscfg_load_owner_info mod_owner = {
+ .type = CSCFG_OWNER_MODULE,
+ .owner_handle = THIS_MODULE,
+};
+
+/* module init and exit - just load and unload configs */
+static int __init cscfg_sample_init(void)
+{
+ return cscfg_load_config_sets(sample_cfgs, sample_feats, &mod_owner);
+}
+
+static void __exit cscfg_sample_exit(void)
+{
+ cscfg_unload_config_sets(&mod_owner);
+}
+
+module_init(cscfg_sample_init);
+module_exit(cscfg_sample_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Mike Leach <mike.leach@linaro.org>");
+MODULE_DESCRIPTION("CoreSight Syscfg Example");