ftl: p2l map on shm

Stores P2L map of open bands in shared memory, allowing for
faster recovery times from application crash.

Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Signed-off-by: Kozlowski Mateusz <mateusz.kozlowski@intel.com>
Change-Id: I519441af05e4d0f57768835bf01c800556873c58
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/13347
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>

lib/ftl/ftl_band.c

@@ -40,6 +40,7 @@ ftl_band_free_p2l_map(struct ftl_band *band)
 	assert(p2l_map->ref_cnt == 0);
 	assert(p2l_map->band_map != NULL);
 
+	band->md->df_p2l_map = FTL_DF_OBJ_ID_INVALID;
 	ftl_mempool_put(dev->p2l_pool, p2l_map->band_map);
 	p2l_map->band_map = NULL;
 }
@@ -309,6 +310,7 @@ ftl_band_alloc_p2l_map(struct ftl_band *band)
 	assert(p2l_map->ref_cnt == 0);
 	assert(p2l_map->band_map == NULL);
 
+	assert(band->md->df_p2l_map == FTL_DF_OBJ_ID_INVALID);
 	p2l_map->band_map = ftl_mempool_get(dev->p2l_pool);
 	if (!p2l_map->band_map) {
 		return -1;
@@ -319,6 +321,8 @@ ftl_band_alloc_p2l_map(struct ftl_band *band)
 		return -1;
 	}
 
+	band->md->df_p2l_map = ftl_mempool_get_df_obj_id(dev->p2l_pool, p2l_map->band_map);
+
 	/* Set the P2L to FTL_LBA_INVALID */
 	memset(p2l_map->band_map, -1, FTL_BLOCK_SIZE * ftl_p2l_map_num_blocks(band->dev));
 

lib/ftl/ftl_band.h

@@ -15,6 +15,8 @@
 #include "ftl_internal.h"
 #include "ftl_core.h"
 
+#include "utils/ftl_df.h"
+
 #define FTL_MAX_OPEN_BANDS 4
 
 #define FTL_BAND_VERSION_0	0
@@ -61,6 +63,9 @@ struct ftl_band_md {
 	/* Number of times band was fully written (ie. number of free -> closed state cycles) */
 	uint64_t			wr_cnt;
 
+	/* Durable format object id for P2L map, allocated on shared memory */
+	ftl_df_obj_id			df_p2l_map;
+
 	/* CRC32 checksum of the associated P2L map when band is in closed state */
 	uint32_t			p2l_map_checksum;
 } __attribute__((aligned(FTL_BLOCK_SIZE)));

lib/ftl/ftl_core.h

@@ -79,6 +79,9 @@ struct spdk_ftl_dev {
 	/* P2L map memory pool */
 	struct ftl_mempool		*p2l_pool;
 
+	/* Underlying SHM buf for LBA map mempool */
+	struct ftl_md			*p2l_pool_md;
+
 	/* Band md memory pool */
 	struct ftl_mempool		*band_md_pool;
 

lib/ftl/mngt/ftl_mngt_band.c

@@ -16,6 +16,7 @@ ftl_band_init_md(struct ftl_band *band)
 	struct ftl_band_md *band_md = ftl_md_get_buffer(band_info_md);
 
 	band->md = &band_md[band->id];
+	band->md->df_p2l_map = FTL_DF_OBJ_ID_INVALID;
 
 	return 0;
 }
@@ -224,6 +225,10 @@ ftl_mngt_finalize_init_bands(struct spdk_ftl_dev *dev, struct ftl_mngt_process *
 	uint64_t i, num_open = 0, num_shut = 0;
 	uint64_t offset;
 
+	TAILQ_FOREACH_SAFE(band, &dev->free_bands, queue_entry, temp_band) {
+		band->md->df_p2l_map = FTL_DF_OBJ_ID_INVALID;
+	}
+
 	TAILQ_FOREACH_SAFE(band, &dev->shut_bands, queue_entry, temp_band) {
 		if (band->md->state == FTL_BAND_STATE_OPEN ||
 		    band->md->state == FTL_BAND_STATE_FULL) {
@@ -241,6 +246,8 @@ ftl_mngt_finalize_init_bands(struct spdk_ftl_dev *dev, struct ftl_mngt_process *
 		} else {
 			num_shut++;
 		}
+
+		band->md->df_p2l_map = FTL_DF_OBJ_ID_INVALID;
 	}
 
 	/* Assign open bands to writers and alloc necessary resources */
@@ -269,6 +276,7 @@ ftl_mngt_finalize_init_bands(struct spdk_ftl_dev *dev, struct ftl_mngt_process *
 		ftl_band_set_owner(band, ftl_writer_band_state_change, writer);
 
 		if (dev->sb->clean) {
+			band->md->df_p2l_map = FTL_DF_OBJ_ID_INVALID;
 			if (ftl_band_alloc_p2l_map(band)) {
 				ftl_mngt_fail_step(mngt);
 				return;

lib/ftl/mngt/ftl_mngt_misc.c

@@ -26,15 +26,25 @@ static int
 init_p2l_map_pool(struct spdk_ftl_dev *dev)
 {
 	size_t p2l_pool_el_blks = spdk_divide_round_up(ftl_p2l_map_pool_elem_size(dev), FTL_BLOCK_SIZE);
+	size_t p2l_pool_buf_blks = P2L_MEMPOOL_SIZE * p2l_pool_el_blks;
+	void *p2l_pool_buf;
 
-	dev->p2l_pool = ftl_mempool_create(P2L_MEMPOOL_SIZE,
+	dev->p2l_pool_md = ftl_md_create(dev, p2l_pool_buf_blks, 0, "p2l_pool",
+					 FTL_MD_CREATE_SHM | FTL_MD_CREATE_SHM_NEW, NULL);
+	if (!dev->p2l_pool_md) {
+		return -ENOMEM;
+	}
+
+	p2l_pool_buf = ftl_md_get_buffer(dev->p2l_pool_md);
+	dev->p2l_pool = ftl_mempool_create_ext(p2l_pool_buf, P2L_MEMPOOL_SIZE,
 					       p2l_pool_el_blks * FTL_BLOCK_SIZE,
-					   FTL_BLOCK_SIZE,
+					       FTL_BLOCK_SIZE);
-					   SPDK_ENV_SOCKET_ID_ANY);
 	if (!dev->p2l_pool) {
 		return -ENOMEM;
 	}
 
+	ftl_mempool_initialize_ext(dev->p2l_pool);
+
 	return 0;
 }
 
@@ -70,10 +80,15 @@ void
 ftl_mngt_deinit_mem_pools(struct spdk_ftl_dev *dev, struct ftl_mngt_process *mngt)
 {
 	if (dev->p2l_pool) {
-		ftl_mempool_destroy(dev->p2l_pool);
+		ftl_mempool_destroy_ext(dev->p2l_pool);
 		dev->p2l_pool = NULL;
 	}
 
+	if (dev->p2l_pool_md) {
+		ftl_md_destroy(dev->p2l_pool_md);
+		dev->p2l_pool_md = NULL;
+	}
+
 	if (dev->band_md_pool) {
 		ftl_mempool_destroy(dev->band_md_pool);
 		dev->band_md_pool = NULL;

test/unit/lib/ftl/common/utils.c

@@ -50,6 +50,12 @@ ftl_mempool_put(struct ftl_mempool *mpool, void *element)
 	spdk_mempool_put((struct spdk_mempool *)mpool, element);
 }
 
+ftl_df_obj_id
+ftl_mempool_get_df_obj_id(struct ftl_mempool *mpool, void *df_obj_ptr)
+{
+	return (ftl_df_obj_id)df_obj_ptr;
+}
+
 struct spdk_ftl_dev *
 test_init_ftl_dev(const struct base_bdev_geometry *geo)
 {
@@ -107,6 +113,7 @@ test_init_ftl_band(struct spdk_ftl_dev *dev, size_t id, size_t zone_size)
 	band->id = id;
 
 	band->md->state = FTL_BAND_STATE_CLOSED;
+	band->md->df_p2l_map = FTL_DF_OBJ_ID_INVALID;
 	TAILQ_INSERT_HEAD(&dev->shut_bands, band, queue_entry);
 
 	band->start_addr = zone_size * id;