From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paul Brook Subject: Re: [PATCH v3 6/6] qemu_calculate_timeout: increase minimum timeout to 1h Date: Fri, 10 Feb 2012 11:09:02 +0000 Message-ID: <201202101109.03374.paul@codesourcery.com> References: <201202100952.26104.paul@codesourcery.com> <4F34F567.3040309@redhat.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-6" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4F34F567.3040309@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org Sender: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org To: Paolo Bonzini Cc: avi@redhat.com, xen-devel@lists.xensource.com, qemu-devel@nongnu.org, Stefano Stabellini List-Id: xen-devel@lists.xenproject.org > >> > At least the floppy DMA engine is fine with it, it uses idle bottom > >> > halves (which are a hack and could be replaced by timers, but that's > >> > not relevant now). > > > > I thought idle bottom halves were one of the things that made this timout > > necessary. How else are they going to get run? > > The timeout is reduced to 10 ms when an idle bottom half is scheduled. > See qemu_bh_update_timeout in async.c. Ah, I see. Idle BH are indeed a nasty hack that should be removed, but not directly relevant to this 1s timeout. I don't think this changes my overall conlusion: Either we need this timeout to poll below the user-thinks-qemu-died threshold, or we should be blocking indefinitely. Paul