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: Mon, 27 Oct 2008 08:56:30 +0100 From: Peter Zijlstra <peterz@...radead.org> To: KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com> Cc: Heiko Carstens <heiko.carstens@...ibm.com>, Nick Piggin <npiggin@...e.de>, linux-kernel@...r.kernel.org, Hugh Dickins <hugh@...itas.com>, Andrew Morton <akpm@...ux-foundation.org>, Linus Torvalds <torvalds@...ux-foundation.org>, Rik van Riel <riel@...hat.com>, Lee Schermerhorn <lee.schermerhorn@...com>, linux-mm@...ck.org, Christoph Lameter <cl@...ux-foundation.org>, Gautham Shenoy <ego@...ibm.com>, Oleg Nesterov <oleg@...sign.ru>, Rusty Russell <rusty@...tcorp.com.au>, mpm <mpm@...enic.com> Subject: Re: [RFC][PATCH] lru_add_drain_all() don't use schedule_on_each_cpu() On Mon, 2008-10-27 at 12:14 +0900, KOSAKI Motohiro wrote: > > Right, and would be about 4k+sizeof(task_struct), some people might be > > bothered, but most won't care. > > > > > Perhaps, I misunderstand your intension. so can you point your > > > previous discussion url? > > > > my google skillz fail me, but once in a while people complain that we > > have too many kernel threads. > > > > Anyway, if we can re-use this per-cpu workqueue for more goals, I guess > > there is even less of an objection. > > In general, you are right. > but this is special case. mmap_sem is really widely used various subsystem and drivers. > (because page fault via copy_user introduce to depend on mmap_sem) > > Then, any work-queue reu-sing can cause similar dead-lock easily. Yeah, I know, and the cpu-hotplug discussion needed another thread due to yet another locking incident. I was hoping these two could go together. Neither are general-purpose workqueues, both need to stay away from the normal eventd due to deadlocks. ego, does you extra thread ever use mmap_sem? -- 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