linux-kernel - [PATCH] libata: use single threaded work queue

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 19 Aug 2009 13:25:54 +0200
From:	Jens Axboe <jens.axboe@...cle.com>
To:	linux-ide@...r.kernel.org, linux-kernel@...r.kernel.org
Cc:	jeff@...zik.org, htejun@...il.com
Subject: [PATCH] libata: use single threaded work queue

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@...cle.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

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/