bdev/ocf: Improve OCF mpools

- Reduce the size of initial memory needed by OCF.
  Number of allocator buffers equal to 16383 is tested to work
  on 24 caches running IO of io_size=512 and io_depth=512, which
  should be more than enough for any real life scenario.
  This reduces initial OCF memory usage from 726 MiB to 392 MiB.
- Fix string handling for the name of the mempool.

Signed-off-by: Rafal Stefanowski <rafal.stefanowski@intel.com>
Change-Id: I40063ab1897c479c25904ae4096c5dae3351f73b
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/10843
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Community-CI: Mellanox Build Bot
Community-CI: Broadcom CI <spdk-ci.pdl@broadcom.com>
Reviewed-by: Tomasz Zawadzki <tomasz.zawadzki@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>

lib/env_ocf/mpool.c

@@ -36,8 +36,6 @@
 
 #include "mpool.h"
 
-#define MEMPOOL_SIZE 24
-
 struct env_mpool {
 	env_allocator *allocator[env_mpool_max];
 	/* Handles to memory pools */
@@ -58,10 +56,10 @@ struct env_mpool {
 struct env_mpool *env_mpool_create(uint32_t hdr_size, uint32_t elem_size,
 				   int flags, int mpool_max, bool fallback,
 				   const uint32_t limits[env_mpool_max],
-				   const char *name_perfix, bool zero)
+				   const char *name_prefix, bool zero)
 {
 	int i;
-	char name[MEMPOOL_SIZE] = {};
+	char name[OCF_ALLOCATOR_NAME_MAX] = {};
 	int ret;
 	int size;
 
@@ -76,7 +74,7 @@ struct env_mpool *env_mpool_create(uint32_t hdr_size, uint32_t elem_size,
 	mpool->fallback = fallback;
 
 	for (i = 0; i < min(env_mpool_max, mpool_max + 1); i++) {
-		ret = snprintf(name, sizeof(name), "%s_%u", name, (1 << i));
+		ret = snprintf(name, sizeof(name), "%s_%u", name_prefix, (1 << i));
 		if (ret < 0 || ret >= (int)sizeof(name)) {
 			goto err;
 		}

lib/env_ocf/ocf_env.c

@@ -43,8 +43,16 @@
  * in itself depends on the workload
  * It is a big number because OCF uses allocators
  * for every request it sends and receives
+ *
+ * The value of 16383 is tested to work on 24 caches
+ * running IO of io_size=512 and io_depth=512, which
+ * should be more than enough for any real life scenario.
+ * Increase this value if needed. It will result in
+ * more memory being used initially on SPDK app start,
+ * when compiled with OCF support.
  */
-#define ENV_ALLOCATOR_NBUFS 32767
+#define ENV_ALLOCATOR_NBUFS 16383
+
 #define GET_ELEMENTS_COUNT(_limit) (_limit < 0 ? ENV_ALLOCATOR_NBUFS : _limit)
 
 /* Use unique index for env allocators */
@@ -76,9 +84,10 @@ env_allocator *
 env_allocator_create_extended(uint32_t size, const char *name, int limit, bool zero)
 {
 	env_allocator *allocator;
-	char qualified_name[128] = {0};
+	char qualified_name[OCF_ALLOCATOR_NAME_MAX] = {0};
 
-	snprintf(qualified_name, 128, "ocf_env_%d", env_atomic_inc_return(&g_env_allocator_index));
+	snprintf(qualified_name, OCF_ALLOCATOR_NAME_MAX, "ocf_env_%d:%s",
+		 env_atomic_inc_return(&g_env_allocator_index), name);
 
 	allocator = calloc(1, sizeof(*allocator));
 	if (!allocator) {

lib/env_ocf/ocf_env.h

@@ -178,7 +178,7 @@ static inline uint64_t env_get_free_memory(void)
 
 /* *** ALLOCATOR *** */
 
-#define OCF_ALLOCATOR_NAME_MAX 128
+#define OCF_ALLOCATOR_NAME_MAX 24
 
 typedef struct {
 	struct spdk_mempool *mempool;

module/bdev/ocf/volume.c

@@ -407,7 +407,7 @@ vbdev_ocf_volume_get_max_io_size(ocf_volume_t volume)
 }
 
 static struct ocf_volume_properties vbdev_volume_props = {
-	.name = "SPDK block device",
+	.name = "SPDK_block_device",
 	.io_priv_size = sizeof(struct ocf_io_ctx),
 	.volume_priv_size = sizeof(struct vbdev_ocf_base *),
 	.caps = {