linux-kernel - Re: [PATCH] smp, ipi: Speed up IPI handling by invoking the callbacks in reverse order

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

Date:	Wed, 4 Jun 2014 21:47:31 +0200
From:	Peter Zijlstra <peterz@...radead.org>
To:	"Srivatsa S. Bhat" <srivatsa.bhat@...ux.vnet.ibm.com>
Cc:	akpm@...ux-foundation.org, fweisbec@...il.com, tglx@...utronix.de,
	hch@...radead.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] smp, ipi: Speed up IPI handling by invoking the
 callbacks in reverse order

On Thu, Jun 05, 2014 at 01:09:35AM +0530, Srivatsa S. Bhat wrote:
> The current implementation of lockless list (llist) has a drawback: if we
> want to traverse the list in FIFO order (oldest to newest), we need to
> reverse the list first (and this can be expensive if the list is large,
> since this is an O(n) operation).

Have you actually looked at the queue depth of this thing? Large queues
are a problem for interrupt latency.
--
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/