[PATCH v3 1/6] coresight: configuration: Update API to introduce load owner concept
Mike Leach
mike.leach at linaro.org
Wed Nov 24 12:00:33 PST 2021
Update the existing load API to introduce a "load owner" concept.
This allows the tracking of the loaded configurations and features against
the loading owner type, to allow later unload according to owner.
A list of loaded configurations by owner is created.
The load owner infrastructure will be used in following patches
to implement dynanic load and unload, alongside dependency tracking.
Signed-off-by: Mike Leach <mike.leach at linaro.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier at linaro.org>
---
.../coresight/coresight-cfg-preload.c | 9 ++++--
.../hwtracing/coresight/coresight-config.h | 5 +++-
.../hwtracing/coresight/coresight-syscfg.c | 21 ++++++++++++--
.../hwtracing/coresight/coresight-syscfg.h | 29 +++++++++++++++++--
4 files changed, 56 insertions(+), 8 deletions(-)
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..6e0d43901d66 100644
--- a/drivers/hwtracing/coresight/coresight-config.h
+++ b/drivers/hwtracing/coresight/coresight-config.h
@@ -97,6 +97,7 @@ 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.
*/
struct cscfg_feature_desc {
const char *name;
@@ -107,6 +108,7 @@ struct cscfg_feature_desc {
struct cscfg_parameter_desc *params_desc;
int nr_regs;
struct cscfg_regval_desc *regs_desc;
+ void *load_owner;
};
/**
@@ -128,7 +130,7 @@ 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.
*/
struct cscfg_config_desc {
const char *name;
@@ -141,6 +143,7 @@ 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;
};
/**
diff --git a/drivers/hwtracing/coresight/coresight-syscfg.c b/drivers/hwtracing/coresight/coresight-syscfg.c
index 43054568430f..021f50949d7b 100644
--- a/drivers/hwtracing/coresight/coresight-syscfg.c
+++ b/drivers/hwtracing/coresight/coresight-syscfg.c
@@ -361,13 +361,22 @@ int cscfg_update_feat_param_val(struct cscfg_feature_desc *feat_desc,
* 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);
@@ -382,6 +391,7 @@ int cscfg_load_config_sets(struct cscfg_config_desc **config_descs,
feat_descs[i]->name);
goto exit_unlock;
}
+ feat_descs[i]->load_owner = owner_info;
i++;
}
}
@@ -398,10 +408,14 @@ int cscfg_load_config_sets(struct cscfg_config_desc **config_descs,
config_descs[i]->name);
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);
+
exit_unlock:
mutex_unlock(&cscfg_mutex);
return err;
@@ -827,10 +841,11 @@ 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..08067e89edcf 100644
--- a/drivers/hwtracing/coresight/coresight-syscfg.h
+++ b/drivers/hwtracing/coresight/coresight-syscfg.h
@@ -25,6 +25,7 @@
* @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.
*/
@@ -33,6 +34,7 @@ struct cscfg_manager {
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;
};
@@ -56,10 +58,32 @@ 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,
+};
+
+/**
+ * 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);
@@ -67,7 +91,8 @@ int cscfg_update_feat_param_val(struct cscfg_feature_desc *feat_desc,
/* 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_register_csdev(struct coresight_device *csdev, u32 match_flags,
struct cscfg_csdev_feat_ops *ops);
void cscfg_unregister_csdev(struct coresight_device *csdev);
--
2.17.1
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