Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 64748b16 authored by Joe Thornber's avatar Joe Thornber Committed by Mike Snitzer
Browse files

dm cache background tracker: limit amount of background work that may be issued at once 



On large systems the cache policy can be over enthusiastic and queue far
too much dirty data to be written back.  This consumes memory.

Signed-off-by: default avatarJoe Thornber <ejt@redhat.com>
Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
parent deb71918

drivers/md/dm-cache-background-tracker.c

+12 −6
Original line number Diff line number Diff line
@@ -161,8 +161,17 @@ EXPORT_SYMBOL_GPL(btracker_nr_demotions_queued); 


static bool max_work_reached(struct background_tracker *b)

{

	// FIXME: finish

	return false;

	return atomic_read(&b->pending_promotes) +

		atomic_read(&b->pending_writebacks) +

		atomic_read(&b->pending_demotes) >= b->max_work;

}



struct bt_work *alloc_work(struct background_tracker *b)

{

	if (max_work_reached(b))

		return NULL;



	return kmem_cache_alloc(b->work_cache, GFP_NOWAIT);

}



int btracker_queue(struct background_tracker *b,
@@ -174,10 +183,7 @@ int btracker_queue(struct background_tracker *b, 
	if (pwork)

		*pwork = NULL;



	if (max_work_reached(b))

		return -ENOMEM;



	w = kmem_cache_alloc(b->work_cache, GFP_NOWAIT);

	w = alloc_work(b);

	if (!w)

		return -ENOMEM;