From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andi Kleen Subject: Re: Some interesting observations when trying to optimize vmstat handling Date: Fri, 9 Nov 2007 16:56:26 +0100 References: <200711090007.43424.ak@suse.de> <4733A7A5.9000900@goop.org> In-Reply-To: <4733A7A5.9000900@goop.org> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200711091656.26908.ak@suse.de> Sender: owner-linux-mm@kvack.org Return-Path: To: Jeremy Fitzhardinge Cc: Christoph Lameter , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Mathieu Desnoyers List-ID: On Friday 09 November 2007 01:19, Jeremy Fitzhardinge wrote: > Andi Kleen wrote: > > The only problem is that there might be some code who relies on > > restore_flags() restoring other flags that IF, but at least for > > interrupts and local_irq_save/restore it should be fine to change. > > I don't think so. We don't bother to save/restore the other flags in > Xen paravirt and it doesn't seem to cause a problem. The semantics > really are specific to the state of the interrupt flag. Yes i checked the code and only case I found is actually save_flags, not restore_flags (and that particular case is even unnecessary) -Andi -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org