[PATCH] libata: use single threaded work queue

[Jens Axboe <jens.axboe@oracle.com>]

Hi,

On boxes with lots of CPUs, we have so many kernel threads it's not
funny. The basic problem is that create_workqueue() creates a per-cpu
thread, where we could easily get by with a single thread for a lot of
cases.

One such case appears to be ata_wq. You want at most one per pio drive,
not one per CPU. I'd suggest just dropping it to a single threaded wq.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 072ba5e..0d78628 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -6580,7 +6580,7 @@ static int __init ata_init(void)
 {
 	ata_parse_force_param();
 
-	ata_wq = create_workqueue("ata");
+	ata_wq = create_singlethread_workqueue("ata");
 	if (!ata_wq)
 		goto free_force_tbl;
 

-- 
Jens Axboe