| 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
| ||
|
Date: Wed, 20 Jul 2011 20:29:21 -0400 (EDT) From: Mikulas Patocka <mpatocka@...hat.com> To: axboe@...nel.dk, "Alasdair G. Kergon" <agk@...hat.com> cc: dm-devel@...hat.com, linux-kernel@...r.kernel.org Subject: [PATCH] backing-dev: use synchronize_rcu_expedited instead of synchronize_rcu Hi Jens Please would you consider taking this into the block tree? It seems to speed up device deletion enormously. Mikulas --- backing-dev: use synchronize_rcu_expedited instead of synchronize_rcu synchronize_rcu sleeps several timer ticks. synchronize_rcu_expedited is much faster. With 100Hz timer frequency, when we remove 10000 block devices with "dmsetup remove_all" command, it takes 27 minutes. With this patch, removing 10000 block devices takes only 15 seconds. Signed-off-by: Mikulas Patocka <mpatocka@...hat.com> --- mm/backing-dev.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) Index: linux-3.0-rc7-fast/mm/backing-dev.c =================================================================== --- linux-3.0-rc7-fast.orig/mm/backing-dev.c 2011-07-19 18:01:00.000000000 +0200 +++ linux-3.0-rc7-fast/mm/backing-dev.c 2011-07-19 18:01:07.000000000 +0200 @@ -505,7 +505,7 @@ static void bdi_remove_from_list(struct list_del_rcu(&bdi->bdi_list); spin_unlock_bh(&bdi_lock); - synchronize_rcu(); + synchronize_rcu_expedited(); } int bdi_register(struct backing_dev_info *bdi, struct device *parent, -- 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/
Powered by blists - more mailing lists