dm cache: track IO to the origin device using io_tracker

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
This commit is contained in:
Joe Thornber 2015-05-15 15:18:01 +01:00 committed by Mike Snitzer
parent 77289d3207
commit 066dbaa386
1 changed files with 49 additions and 7 deletions

View File

@ -355,6 +355,8 @@ struct cache {
*/
spinlock_t invalidation_lock;
struct list_head invalidation_requests;
struct io_tracker origin_tracker;
};
struct per_bio_data {
@ -362,6 +364,7 @@ struct per_bio_data {
unsigned req_nr:2;
struct dm_deferred_entry *all_io_entry;
struct dm_hook_info hook_info;
sector_t len;
/*
* writethrough fields. These MUST remain at the end of this
@ -768,6 +771,7 @@ static struct per_bio_data *init_per_bio_data(struct bio *bio, size_t data_size)
pb->tick = false;
pb->req_nr = dm_bio_get_target_bio_nr(bio);
pb->all_io_entry = NULL;
pb->len = 0;
return pb;
}
@ -865,12 +869,43 @@ static void inc_ds(struct cache *cache, struct bio *bio,
pb->all_io_entry = dm_deferred_entry_inc(cache->all_io_ds);
}
static bool accountable_bio(struct cache *cache, struct bio *bio)
{
return ((bio->bi_bdev == cache->origin_dev->bdev) &&
!(bio->bi_rw & REQ_DISCARD));
}
static void accounted_begin(struct cache *cache, struct bio *bio)
{
size_t pb_data_size = get_per_bio_data_size(cache);
struct per_bio_data *pb = get_per_bio_data(bio, pb_data_size);
if (accountable_bio(cache, bio)) {
pb->len = bio_sectors(bio);
iot_io_begin(&cache->origin_tracker, pb->len);
}
}
static void accounted_complete(struct cache *cache, struct bio *bio)
{
size_t pb_data_size = get_per_bio_data_size(cache);
struct per_bio_data *pb = get_per_bio_data(bio, pb_data_size);
iot_io_end(&cache->origin_tracker, pb->len);
}
static void accounted_request(struct cache *cache, struct bio *bio)
{
accounted_begin(cache, bio);
generic_make_request(bio);
}
static void issue(struct cache *cache, struct bio *bio)
{
unsigned long flags;
if (!bio_triggers_commit(cache, bio)) {
generic_make_request(bio);
accounted_request(cache, bio);
return;
}
@ -1166,7 +1201,7 @@ static void issue_overwrite(struct dm_cache_migration *mg, struct bio *bio)
* No need to inc_ds() here, since the cell will be held for the
* duration of the io.
*/
generic_make_request(bio);
accounted_request(mg->cache, bio);
}
static bool bio_writes_complete_block(struct cache *cache, struct bio *bio)
@ -1722,7 +1757,7 @@ static void process_deferred_flush_bios(struct cache *cache, bool submit_bios)
* These bios have already been through inc_ds()
*/
while ((bio = bio_list_pop(&bios)))
submit_bios ? generic_make_request(bio) : bio_io_error(bio);
submit_bios ? accounted_request(cache, bio) : bio_io_error(bio);
}
static void process_deferred_writethrough_bios(struct cache *cache)
@ -1742,7 +1777,7 @@ static void process_deferred_writethrough_bios(struct cache *cache)
* These bios have already been through inc_ds()
*/
while ((bio = bio_list_pop(&bios)))
generic_make_request(bio);
accounted_request(cache, bio);
}
static void writeback_some_dirty_blocks(struct cache *cache)
@ -2602,6 +2637,8 @@ static int cache_create(struct cache_args *ca, struct cache **result)
spin_lock_init(&cache->invalidation_lock);
INIT_LIST_HEAD(&cache->invalidation_requests);
iot_init(&cache->origin_tracker);
*result = cache;
return 0;
@ -2791,9 +2828,13 @@ static int cache_map(struct dm_target *ti, struct bio *bio)
struct cache *cache = ti->private;
r = __cache_map(cache, bio, &cell);
if (r == DM_MAPIO_REMAPPED && cell) {
inc_ds(cache, bio, cell);
cell_defer(cache, cell, false);
if (r == DM_MAPIO_REMAPPED) {
accounted_begin(cache, bio);
if (cell) {
inc_ds(cache, bio, cell);
cell_defer(cache, cell, false);
}
}
return r;
@ -2815,6 +2856,7 @@ static int cache_end_io(struct dm_target *ti, struct bio *bio, int error)
}
check_for_quiesced_migrations(cache, pb);
accounted_complete(cache, bio);
return 0;
}