Introduce ocf_cache_has_pending_cleaning() function

Signed-off-by: Robert Baldyga <robert.baldyga@intel.com>

inc/ocf_cache.h

@@ -174,6 +174,13 @@ void ocf_cache_wait_for_io_finish(ocf_cache_t cache);
  */
 bool ocf_cache_has_pending_requests(ocf_cache_t cache);
 
+/**
+ * @brief Check if cleaning triggered by eviction runs on the cache
+ *
+ * @param[in] cache Cache object
+ */
+bool ocf_cache_has_pending_cleaning(ocf_cache_t cache);
+
 /**
  * @brief Get cache mode of given cache object
  *

src/mngt/ocf_mngt_common.c

@@ -9,7 +9,6 @@
 #include "../ocf_ctx_priv.h"
 #include "../metadata/metadata.h"
 #include "../engine/cache_engine.h"
-#include "../utils/utils_part.h"
 #include "../utils/utils_req.h"
 #include "../utils/utils_device.h"
 #include "../eviction/ops.h"
@@ -118,53 +117,6 @@ void cache_mng_core_remove_from_cache(struct ocf_cache *cache, int core_id)
 	cache->conf_meta->core_count--;
 }
 
-/**
- * @brief Wait for the end of asynchronous cleaning
- *
- * @param cache OCF cache instance
- * @param timeout_ms Timeout for waiting in milliseconds
- * @note When timeout is less than zero it means wait forever
- *
- * @retval 0 cleaning finished
- * @retval non-zero timeout and cleaning still in progress
- */
-static int _ocf_cleaning_wait_for_finish(struct ocf_cache *cache,
-		const int32_t timeout_ms)
-{
-	struct ocf_user_part *curr_part;
-	ocf_part_id_t part_id;
-	bool cleaning_active = ocf_cache_is_device_attached(cache);
-	int64_t _timeout = timeout_ms;
-
-	while (cleaning_active) {
-		cleaning_active = false;
-
-		OCF_METADATA_LOCK_WR();
-		for_each_part(cache, curr_part, part_id) {
-			if (env_atomic_read(&cache->cleaning[part_id])) {
-				cleaning_active = true;
-				break;
-			}
-		}
-		OCF_METADATA_UNLOCK_WR();
-
-		if (cleaning_active) {
-			env_msleep(20);
-
-			if (timeout_ms >= 0) {
-				_timeout -= 20;
-				if (_timeout <= 0)
-					break;
-			}
-		}
-	};
-
-	if (cleaning_active)
-		return -EBUSY;
-
-	return 0;
-}
-
 void ocf_mngt_cache_put(ocf_cache_t cache)
 {
 	OCF_CHECK_NULL(cache);
@@ -275,15 +227,6 @@ static int _ocf_mngt_cache_lock(ocf_cache_t cache, int (*lock_fn)(env_rwsem *s),
 		goto unlock;
 	}
 
-	/* Return, when asynchronous cleaning is finished */
-	if (_ocf_cleaning_wait_for_finish(cache, 60 * 1000)) {
-		/* Because of some reasons, asynchronous cleaning still active,
-		 * cannot continue
-		 */
-		ret = -OCF_ERR_CACHE_IN_USE;
-		goto unlock;
-	}
-
 	return 0;
 
 unlock:
@@ -321,15 +264,15 @@ int ocf_mngt_cache_read_trylock(ocf_cache_t cache)
 }
 
 /* if cache is either fully initialized or during recovery */
-static ocf_cache_t _ocf_mngt_cache_try_get(ocf_cache_t cache)
+static bool _ocf_mngt_cache_try_get(ocf_cache_t cache)
 {
 	if (!!cache->valid_ocf_cache_device_t) {
 		/* Increase reference counter */
 		env_atomic_inc(&cache->ref_count);
-		return cache;
+		return true;
 	}
 
-	return NULL;
+	return false;
 }
 
 int ocf_mngt_cache_get(ocf_cache_t cache)
@@ -345,7 +288,7 @@ static int _ocf_mngt_cache_get_list_cpy(ocf_ctx_t ocf_ctx, ocf_cache_t **list,
 {
 	int result = 0;
 	uint32_t count = 0, i = 0;
-	struct ocf_cache *iter, *this;
+	ocf_cache_t iter;
 
 	*list = NULL;
 	*size = 0;
@@ -366,12 +309,9 @@ static int _ocf_mngt_cache_get_list_cpy(ocf_ctx_t ocf_ctx, ocf_cache_t **list,
 	}
 
 	list_for_each_entry(iter, &ocf_ctx->caches, list) {
-		this = _ocf_mngt_cache_try_get(iter);
 
-		if (this) {
+		if (_ocf_mngt_cache_try_get(iter))
-			(*list)[i] = this;
+			(*list)[i++] = iter;
-			i++;
-		}
 	}
 
 	if (i) {

src/mngt/ocf_mngt_core.c

@@ -588,6 +588,26 @@ err_pipeline:
 	cmpl(cache, NULL, priv, result);
 }
 
+/*
+ * Synchronously wait until cleaning triggered by eviction finishes.
+ * TODO: Replace it with asynchronous mechanism.
+ */
+static int _ocf_cleaning_wait_for_finish(ocf_cache_t cache, int32_t timeout_ms)
+{
+	if (!ocf_cache_is_device_attached(cache))
+		return 0;
+
+	while (ocf_cache_has_pending_cleaning(cache)) {
+		env_msleep(20);
+
+		timeout_ms -= 20;
+		if (timeout_ms <= 0)
+			return -EBUSY;
+	}
+
+	return 0;
+}
+
 struct ocf_mngt_cache_remove_core_context {
 	ocf_mngt_cache_remove_core_end_t cmpl;
 	void *priv;
@@ -650,6 +670,12 @@ void ocf_mngt_cache_remove_core(ocf_core_t core,
 	cache = ocf_core_get_cache(core);
 	core_id = ocf_core_get_id(core);
 
+	/* TODO: Make this asynchronous */
+	if (_ocf_cleaning_wait_for_finish(cache, 60 * 1000)) {
+		cmpl(priv, -OCF_ERR_CACHE_IN_USE);
+		return;
+	}
+
 	result = ocf_pipeline_create(&pipeline, cache,
 			&ocf_mngt_cache_remove_core_pipeline_props);
 	if (result) {
@@ -702,10 +728,21 @@ static int _ocf_mngt_cache_detach_core(ocf_core_t core)
 void ocf_mngt_cache_detach_core(ocf_core_t core,
 		ocf_mngt_cache_detach_core_end_t cmpl, void *priv)
 {
-	ocf_cache_t cache = ocf_core_get_cache(core);
+	ocf_cache_t cache;
-	const char *core_name = ocf_core_get_name(core);
+	const char *core_name;
 	int result;
 
+	OCF_CHECK_NULL(core);
+
+	cache = ocf_core_get_cache(core);
+	core_name = ocf_core_get_name(core);
+
+	/* TODO: Make this asynchronous */
+	if (_ocf_cleaning_wait_for_finish(cache, 60 * 1000)) {
+		cmpl(priv, -OCF_ERR_CACHE_IN_USE);
+		return;
+	}
+
 	ocf_core_log(core, log_debug, "Detaching core\n");
 
 	result = _ocf_mngt_cache_detach_core(core);

src/ocf_cache.c

@@ -8,6 +8,7 @@
 #include "engine/cache_engine.h"
 #include "utils/utils_cache_line.h"
 #include "utils/utils_req.h"
+#include "utils/utils_part.h"
 #include "ocf_priv.h"
 #include "ocf_cache_priv.h"
 
@@ -68,12 +69,42 @@ void ocf_cache_wait_for_io_finish(ocf_cache_t cache)
 bool ocf_cache_has_pending_requests(ocf_cache_t cache)
 {
 	OCF_CHECK_NULL(cache);
+
 	return ocf_req_get_allocated(cache) > 0;
 }
 
+/*
+ * This is temporary workaround allowing to check if cleaning triggered
+ * by eviction policy is running on the cache. This information is needed
+ * to remove core from cache properly.
+ *
+ * TODO: Replace this with asynchronous notification to which remove/detach
+ * core pipelines can subscribe.
+ */
+bool ocf_cache_has_pending_cleaning(ocf_cache_t cache)
+{
+	struct ocf_user_part *curr_part;
+	ocf_part_id_t part_id;
+	bool cleaning_active = false;
+
+	OCF_CHECK_NULL(cache);
+
+	OCF_METADATA_LOCK_RD();
+	for_each_part(cache, curr_part, part_id) {
+		if (env_atomic_read(&cache->cleaning[part_id])) {
+			cleaning_active = true;
+			break;
+		}
+	}
+	OCF_METADATA_UNLOCK_RD();
+
+	return cleaning_active;
+}
+
 ocf_cache_mode_t ocf_cache_get_mode(ocf_cache_t cache)
 {
 	OCF_CHECK_NULL(cache);
+
 	return cache->conf_meta->cache_mode;
 }