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>
diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c
index 6f9bdd1..940c7b2 100644
--- a/drivers/md/dm-cache-target.c
+++ b/drivers/md/dm-cache-target.c
@@ -355,6 +355,8 @@
*/
spinlock_t invalidation_lock;
struct list_head invalidation_requests;
+
+ struct io_tracker origin_tracker;
};
struct per_bio_data {
@@ -362,6 +364,7 @@
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 @@
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 @@
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 @@
* 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 @@
* 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 @@
* 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 @@
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 @@
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 @@
}
check_for_quiesced_migrations(cache, pb);
+ accounted_complete(cache, bio);
return 0;
}