Introduce core refcount

src/mngt/ocf_mngt_cache.c

@@ -427,6 +427,8 @@ static void _ocf_mngt_deinit_added_cores(
 		ocf_core_seq_cutoff_deinit(core);
 		ocf_core_seq_detect_deinit(core);
 
+		if (core->counters)
+			env_refcnt_deinit(&core->refcnt);
 		env_free(core->counters);
 		core->counters = NULL;
 		core->added = false;
@@ -511,6 +513,13 @@ static void _ocf_mngt_load_add_cores(ocf_pipeline_t pipeline,
 		if (!core->counters)
 			goto err;
 
+		ret = env_refcnt_init(&core->refcnt, "core", sizeof("core"));
+		if (ret) {
+			env_free(core->counters);
+			core->counters = NULL;
+			goto err;
+		}
+
 		ret = ocf_core_seq_detect_init(core);
 		if (ret < 0)
 			goto err;

src/mngt/ocf_mngt_common.c

@@ -136,6 +136,7 @@ void cache_mngt_core_remove_from_cache(ocf_core_t core)
 	ocf_prefetch_deinit(cache, core);
 	ocf_core_seq_cutoff_deinit(core);
 	ocf_core_seq_detect_deinit(core);
+	env_refcnt_deinit(&core->refcnt);
 	env_free(core->counters);
 	core->counters = NULL;
 	core->added = false;

src/mngt/ocf_mngt_core.c

@@ -151,6 +151,7 @@ static void _ocf_mngt_cache_add_core_handle_error(
 		core->added = false;
 		core->opened = false;
 
+		env_refcnt_deinit(&core->refcnt);
 		env_free(core->counters);
 		core->counters = NULL;
 	}
@@ -497,6 +498,13 @@ static void ocf_mngt_cache_add_core_insert(ocf_pipeline_t pipeline,
 	if (!core->counters)
 		OCF_PL_FINISH_RET(context->pipeline, -OCF_ERR_NO_MEM);
 
+	result = env_refcnt_init(&core->refcnt, "core", sizeof("core"));
+	if (result) {
+		env_free(core->counters);
+		core->counters = NULL;
+		OCF_PL_FINISH_RET(context->pipeline, result);
+	}
+
 	context->flags.counters_allocated = true;
 
 	/* When adding new core to cache, reset all core/cache statistics */
@@ -665,6 +673,7 @@ struct ocf_mngt_cache_remove_core_context {
 	ocf_core_t core;
 	const char *core_name;
 	struct ocf_cleaner_wait_context cleaner_wait;
+	bool core_frozen;
 };
 
 static void ocf_mngt_cache_remove_core_finish(ocf_pipeline_t pipeline,
@@ -681,6 +690,9 @@ static void ocf_mngt_cache_remove_core_finish(ocf_pipeline_t pipeline,
 				context->core_name);
 	}
 
+	if (context->core_frozen)
+		env_refcnt_unfreeze(&context->core->refcnt);
+
 	if (ocf_cache_is_device_attached(cache)) {
 		ocf_cleaner_refcnt_unfreeze(cache);
 	}
@@ -741,6 +753,7 @@ static void _ocf_mngt_cache_remove_core(ocf_pipeline_t pipeline, void *priv,
 		cache_mngt_core_remove_from_cleaning_pol(core);
 
 	cache_mngt_core_remove_from_meta(core);
+	context->core_frozen = false;
 	cache_mngt_core_remove_from_cache(core);
 	cache_mngt_core_deinit(core);
 
@@ -752,6 +765,17 @@ static void _ocf_mngt_cache_remove_core(ocf_pipeline_t pipeline, void *priv,
 			context);
 }
 
+static void ocf_mngt_cache_remove_core_wait_requests(ocf_pipeline_t pipeline,
+		void *priv, ocf_pipeline_arg_t arg)
+{
+	struct ocf_mngt_cache_remove_core_context *context = priv;
+	ocf_core_t core = context->core;
+
+	env_refcnt_freeze(&core->refcnt);
+	context->core_frozen = true;
+	ocf_pipeline_continue_on_zero_refcnt(pipeline, &core->refcnt);
+}
+
 static void ocf_mngt_cache_remove_core_wait_cleaning_complete(void *priv)
 {
 	ocf_pipeline_t pipeline = priv;
@@ -778,6 +802,7 @@ struct ocf_pipeline_properties ocf_mngt_cache_remove_core_pipeline_props = {
 	.finish = ocf_mngt_cache_remove_core_finish,
 	.steps = {
 		OCF_PL_STEP(ocf_mngt_cache_remove_core_wait_cleaning),
+		OCF_PL_STEP(ocf_mngt_cache_remove_core_wait_requests),
 		OCF_PL_STEP(_ocf_mngt_cache_remove_core_mapping),
 		OCF_PL_STEP(_ocf_mngt_cache_remove_core),
 		OCF_PL_STEP_TERMINATOR(),

src/ocf_core_priv.h

@@ -51,6 +51,8 @@ struct ocf_core {
 
 	struct ocf_counters_core *counters;
 
+	struct env_refcnt refcnt;
+
 	void *priv;
 };
 

src/ocf_request.c

@@ -197,6 +197,9 @@ struct ocf_request *ocf_req_new(ocf_queue_t queue, ocf_core_t core,
 
 	ENV_BUG_ON(ocf_queue_is_mngt(queue));
 
+	if (!env_refcnt_inc(&core->refcnt))
+		return NULL;
+
 	ocf_queue_get(queue);
 
 	if (!env_refcnt_inc(&cache->refcnt.metadata)) {
@@ -205,6 +208,7 @@ struct ocf_request *ocf_req_new(ocf_queue_t queue, ocf_core_t core,
 		req = ocf_req_new_d2c(queue, core, addr, bytes, rw);
 		if (unlikely(!req)) {
 			ocf_queue_put(queue);
+			env_refcnt_dec(&core->refcnt);
 			return NULL;
 		}
 		return req;
@@ -229,6 +233,7 @@ struct ocf_request *ocf_req_new(ocf_queue_t queue, ocf_core_t core,
 	if (unlikely(!req)) {
 		env_refcnt_dec(&cache->refcnt.metadata);
 		ocf_queue_put(queue);
+		env_refcnt_dec(&core->refcnt);
 		return NULL;
 	}
 
@@ -304,6 +309,7 @@ struct ocf_request *ocf_req_new_cache(ocf_cache_t cache, ocf_queue_t queue,
 	ocf_req_init(req, cache, queue, NULL, addr, bytes, rw);
 
 	req->lock_idx = ocf_metadata_concurrency_next_idx(queue);
+	req->is_cache = true;
 
 	return req;
 }
@@ -398,6 +404,9 @@ void ocf_req_put(struct ocf_request *req)
 	else if (!req->is_mngt || req->cleaner)
 		env_refcnt_dec(&req->cache->refcnt.metadata);
 
+	if (!req->is_mngt && !req->cleaner && !req->is_cache)
+		env_refcnt_dec(&req->core->refcnt);
+
 	if (unlikely(req->is_mngt)) {
 		env_free(req);
 	} else {

src/ocf_request.h

@@ -303,6 +303,9 @@ struct ocf_request {
 	uint8_t is_mngt : 1;
 	/* !< It's a management path request */
 
+	uint8_t is_cache : 1;
+	/* !< It's a cache volume request */
+
 	ocf_req_cache_mode_t cache_mode;
 
 	ocf_queue_t io_queue;