linux-kernel - Re: [PATCH] irq: better struct irqaction layout

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] [day] [month] [year] [list]

Message-ID: <20101104143539.GE32383@basil.fritz.box>
Date:	Thu, 4 Nov 2010 15:35:40 +0100
From:	Andi Kleen <andi@...stfloor.org>
To:	Eric Dumazet <eric.dumazet@...il.com>
Cc:	Ingo Molnar <mingo@...e.hu>, Thomas Gleixner <tglx@...utronix.de>,
	linux-kernel <linux-kernel@...r.kernel.org>,
	Andi Kleen <andi@...stfloor.org>,
	Peter Zijlstra <peterz@...radead.org>
Subject: Re: [PATCH] irq: better struct irqaction layout

On Thu, Nov 04, 2010 at 11:13:48AM +0100, Eric Dumazet wrote:
> We currently use kmalloc-96 slab for struct irqaction allocations on
> 64bit arches.
> 
> This is unfortunate because of possible false sharing and two cache
> lines accesses.
> 
> Move 'name' and 'dir' fields at the end of the structure, and force a
> suitable alignement.
> 
> Hot path fields now use one cache line on x86_64.

Looks good.  It would be nice if some of the fields could be merged (like
thread_flags and flags), but I assume it would be tought to get it back
to 64 bytes again.

Reviewed-by: Andi Kleen <ak@...ux.intel.com>
-Andi
--
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/