lib: scatterlist: move SG pool code from SCSI driver to lib/sg_pool.c

Now it's ready to move the mempool based SG chained allocator code from
SCSI driver to lib/sg_pool.c, which will be compiled only based on a Kconfig
symbol CONFIG_SG_POOL.

SCSI selects CONFIG_SG_POOL.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lin <ming.l@ssi.samsung.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Ming Lin
2016-04-04 14:48:11 -07:00
committed by Martin K. Petersen
parent 65e8617fba
commit 9b1d6c8950
7 changed files with 206 additions and 156 deletions

View File

@@ -14,8 +14,6 @@
#include <linux/completion.h>
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/mempool.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/delay.h>
@@ -40,39 +38,6 @@
#include "scsi_logging.h"
#define SG_MEMPOOL_NR ARRAY_SIZE(sg_pools)
#define SG_MEMPOOL_SIZE 2
struct sg_pool {
size_t size;
char *name;
struct kmem_cache *slab;
mempool_t *pool;
};
#define SP(x) { .size = x, "sgpool-" __stringify(x) }
#if (SG_CHUNK_SIZE < 32)
#error SG_CHUNK_SIZE is too small (must be 32 or greater)
#endif
static struct sg_pool sg_pools[] = {
SP(8),
SP(16),
#if (SG_CHUNK_SIZE > 32)
SP(32),
#if (SG_CHUNK_SIZE > 64)
SP(64),
#if (SG_CHUNK_SIZE > 128)
SP(128),
#if (SG_CHUNK_SIZE > 256)
#error SG_CHUNK_SIZE is too large (256 MAX)
#endif
#endif
#endif
#endif
SP(SG_CHUNK_SIZE)
};
#undef SP
struct kmem_cache *scsi_sdb_cache;
/*
@@ -553,65 +518,6 @@ void scsi_run_host_queues(struct Scsi_Host *shost)
scsi_run_queue(sdev->request_queue);
}
static inline unsigned int sg_pool_index(unsigned short nents)
{
unsigned int index;
BUG_ON(nents > SG_CHUNK_SIZE);
if (nents <= 8)
index = 0;
else
index = get_count_order(nents) - 3;
return index;
}
static void sg_pool_free(struct scatterlist *sgl, unsigned int nents)
{
struct sg_pool *sgp;
sgp = sg_pools + sg_pool_index(nents);
mempool_free(sgl, sgp->pool);
}
static struct scatterlist *sg_pool_alloc(unsigned int nents, gfp_t gfp_mask)
{
struct sg_pool *sgp;
sgp = sg_pools + sg_pool_index(nents);
return mempool_alloc(sgp->pool, gfp_mask);
}
static void sg_free_table_chained(struct sg_table *table, bool first_chunk)
{
if (first_chunk && table->orig_nents <= SG_CHUNK_SIZE)
return;
__sg_free_table(table, SG_CHUNK_SIZE, first_chunk, sg_pool_free);
}
static int sg_alloc_table_chained(struct sg_table *table, int nents,
struct scatterlist *first_chunk)
{
int ret;
BUG_ON(!nents);
if (first_chunk) {
if (nents <= SG_CHUNK_SIZE) {
table->nents = table->orig_nents = nents;
sg_init_table(table->sgl, nents);
return 0;
}
}
ret = __sg_alloc_table(table, nents, SG_CHUNK_SIZE,
first_chunk, GFP_ATOMIC, sg_pool_alloc);
if (unlikely(ret))
sg_free_table_chained(table, (bool)first_chunk);
return ret;
}
static void scsi_uninit_cmd(struct scsi_cmnd *cmd)
{
if (cmd->request->cmd_type == REQ_TYPE_FS) {
@@ -2269,8 +2175,6 @@ EXPORT_SYMBOL(scsi_unblock_requests);
int __init scsi_init_queue(void)
{
int i;
scsi_sdb_cache = kmem_cache_create("scsi_data_buffer",
sizeof(struct scsi_data_buffer),
0, 0, NULL);
@@ -2279,53 +2183,12 @@ int __init scsi_init_queue(void)
return -ENOMEM;
}
for (i = 0; i < SG_MEMPOOL_NR; i++) {
struct sg_pool *sgp = sg_pools + i;
int size = sgp->size * sizeof(struct scatterlist);
sgp->slab = kmem_cache_create(sgp->name, size, 0,
SLAB_HWCACHE_ALIGN, NULL);
if (!sgp->slab) {
printk(KERN_ERR "SCSI: can't init sg slab %s\n",
sgp->name);
goto cleanup_sdb;
}
sgp->pool = mempool_create_slab_pool(SG_MEMPOOL_SIZE,
sgp->slab);
if (!sgp->pool) {
printk(KERN_ERR "SCSI: can't init sg mempool %s\n",
sgp->name);
goto cleanup_sdb;
}
}
return 0;
cleanup_sdb:
for (i = 0; i < SG_MEMPOOL_NR; i++) {
struct sg_pool *sgp = sg_pools + i;
if (sgp->pool)
mempool_destroy(sgp->pool);
if (sgp->slab)
kmem_cache_destroy(sgp->slab);
}
kmem_cache_destroy(scsi_sdb_cache);
return -ENOMEM;
}
void scsi_exit_queue(void)
{
int i;
kmem_cache_destroy(scsi_sdb_cache);
for (i = 0; i < SG_MEMPOOL_NR; i++) {
struct sg_pool *sgp = sg_pools + i;
mempool_destroy(sgp->pool);
kmem_cache_destroy(sgp->slab);
}
}
/**