From: Tejun Heo Date: Thu, 13 Jan 2011 19:59:59 +0000 (+0000) Subject: dm snapshot: persistent make metadata_wq multithreaded X-Git-Tag: firefly_0821_release~7613^2~2867^2~7 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=239c8dd533e74de4a7f3c85c4f9f430eb08867c1;p=firefly-linux-kernel-4.4.55.git dm snapshot: persistent make metadata_wq multithreaded metadata_wq serves on-stack work items from chunk_io(). Even if multiple chunk_io() are simultaneously in progress, each is independent and queued only once, so multithreaded workqueue can be safely used. Switch metadata_wq to multithread and flush the work item instead of the workqueue in chunk_io(). Signed-off-by: Tejun Heo Signed-off-by: Mike Snitzer Signed-off-by: Alasdair G Kergon --- diff --git a/drivers/md/dm-snap-persistent.c b/drivers/md/dm-snap-persistent.c index d3021a69c857..95891dfcbca0 100644 --- a/drivers/md/dm-snap-persistent.c +++ b/drivers/md/dm-snap-persistent.c @@ -256,7 +256,7 @@ static int chunk_io(struct pstore *ps, void *area, chunk_t chunk, int rw, */ INIT_WORK_ONSTACK(&req.work, do_metadata); queue_work(ps->metadata_wq, &req.work); - flush_workqueue(ps->metadata_wq); + flush_work(&req.work); return req.result; } @@ -818,7 +818,7 @@ static int persistent_ctr(struct dm_exception_store *store, atomic_set(&ps->pending_count, 0); ps->callbacks = NULL; - ps->metadata_wq = alloc_ordered_workqueue("ksnaphd", WQ_MEM_RECLAIM); + ps->metadata_wq = alloc_workqueue("ksnaphd", WQ_MEM_RECLAIM, 0); if (!ps->metadata_wq) { kfree(ps); DMERR("couldn't start header metadata update thread");