dm: ensure bio-based DM's bioset and io_pool support targets' maximum IOs

alloc_multiple_bios() assumes it can allocate the requested number of
bios but until now there was no gaurantee that the mempools would be
accomodating.

Suggested-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
This commit is contained in:
Mike Snitzer 2017-12-08 14:40:52 -05:00
parent 4a3f54d94d
commit 0776aa0e30
3 changed files with 27 additions and 15 deletions

View File

@ -1079,7 +1079,8 @@ static int dm_table_alloc_md_mempools(struct dm_table *t, struct mapped_device *
{
enum dm_queue_mode type = dm_table_get_type(t);
unsigned per_io_data_size = 0;
struct dm_target *tgt;
unsigned min_pool_size = 0;
struct dm_target *ti;
unsigned i;
if (unlikely(type == DM_TYPE_NONE)) {
@ -1089,11 +1090,13 @@ static int dm_table_alloc_md_mempools(struct dm_table *t, struct mapped_device *
if (__table_type_bio_based(type))
for (i = 0; i < t->num_targets; i++) {
tgt = t->targets + i;
per_io_data_size = max(per_io_data_size, tgt->per_io_data_size);
ti = t->targets + i;
per_io_data_size = max(per_io_data_size, ti->per_io_data_size);
min_pool_size = max(min_pool_size, ti->num_flush_bios);
}
t->mempools = dm_alloc_md_mempools(md, type, t->integrity_supported, per_io_data_size);
t->mempools = dm_alloc_md_mempools(md, type, t->integrity_supported,
per_io_data_size, min_pool_size);
if (!t->mempools)
return -ENOMEM;

View File

@ -1810,17 +1810,26 @@ static void __bind_mempools(struct mapped_device *md, struct dm_table *t)
{
struct dm_md_mempools *p = dm_table_get_md_mempools(t);
if (md->bs) {
/* The md already has necessary mempools. */
if (dm_table_bio_based(t)) {
/* The md may already have mempools that need changing. */
if (md->bs) {
/*
* Reload bioset because front_pad may have changed
* because a different table was loaded.
*/
bioset_free(md->bs);
md->bs = p->bs;
p->bs = NULL;
md->bs = NULL;
}
if (md->io_pool) {
/*
* Reload io_pool because pool_size may have changed
* because a different table was loaded.
*/
mempool_destroy(md->io_pool);
md->io_pool = NULL;
}
} else if (md->bs) {
/*
* There's no need to reload with request-based dm
* because the size of front_pad doesn't change.
@ -1838,7 +1847,6 @@ static void __bind_mempools(struct mapped_device *md, struct dm_table *t)
p->io_pool = NULL;
md->bs = p->bs;
p->bs = NULL;
out:
/* mempool bind completed, no longer need any mempools in the table */
dm_table_free_md_mempools(t);
@ -2727,7 +2735,8 @@ int dm_noflush_suspending(struct dm_target *ti)
EXPORT_SYMBOL_GPL(dm_noflush_suspending);
struct dm_md_mempools *dm_alloc_md_mempools(struct mapped_device *md, enum dm_queue_mode type,
unsigned integrity, unsigned per_io_data_size)
unsigned integrity, unsigned per_io_data_size,
unsigned min_pool_size)
{
struct dm_md_mempools *pools = kzalloc_node(sizeof(*pools), GFP_KERNEL, md->numa_node_id);
unsigned int pool_size = 0;
@ -2739,16 +2748,15 @@ struct dm_md_mempools *dm_alloc_md_mempools(struct mapped_device *md, enum dm_qu
switch (type) {
case DM_TYPE_BIO_BASED:
case DM_TYPE_DAX_BIO_BASED:
pool_size = dm_get_reserved_bio_based_ios();
pool_size = max(dm_get_reserved_bio_based_ios(), min_pool_size);
front_pad = roundup(per_io_data_size, __alignof__(struct dm_target_io)) + offsetof(struct dm_target_io, clone);
pools->io_pool = mempool_create_slab_pool(pool_size, _io_cache);
if (!pools->io_pool)
goto out;
break;
case DM_TYPE_REQUEST_BASED:
case DM_TYPE_MQ_REQUEST_BASED:
pool_size = dm_get_reserved_rq_based_ios();
pool_size = max(dm_get_reserved_rq_based_ios(), min_pool_size);
front_pad = offsetof(struct dm_rq_clone_bio_info, clone);
/* per_io_data_size is used for blk-mq pdu at queue allocation */
break;

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@ -206,7 +206,8 @@ void dm_kcopyd_exit(void);
* Mempool operations
*/
struct dm_md_mempools *dm_alloc_md_mempools(struct mapped_device *md, enum dm_queue_mode type,
unsigned integrity, unsigned per_bio_data_size);
unsigned integrity, unsigned per_bio_data_size,
unsigned min_pool_size);
void dm_free_md_mempools(struct dm_md_mempools *pools);
/*