From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [patch 1/2] QEMU: use SIGARLM for alarm timers, enable SIGIO on qemu_set_fd_handler2() Date: Sun, 13 Apr 2008 18:05:38 +0300 Message-ID: <48022142.7060209@qumranet.com> References: <20080411183852.150819622@localhost.localdomain> <20080411184851.494350385@localhost.localdomain> <47FFB517.9070800@us.ibm.com> <20080411194457.GA4869@dmt> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm-devel@lists.sourceforge.net To: Marcelo Tosatti Return-path: In-Reply-To: <20080411194457.GA4869@dmt> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces@lists.sourceforge.net Errors-To: kvm-devel-bounces@lists.sourceforge.net List-Id: kvm.vger.kernel.org Marcelo Tosatti wrote: > On Fri, Apr 11, 2008 at 01:59:35PM -0500, Anthony Liguori wrote: > >> With the IO thread, shouldn't we be striving to perform the select()s >> within the IO thread itself to completely avoid the need to use SIGIO at >> all? >> > > Fully agree. Problem with it are the fundamental changes in qemu that > are required (and the difficulty merging those in qemu). > > One is tempted to use pselect() to temporarily unblock the signals while waiting. This has two problems, though: one, pselect() is emulated in libc with older kernels, and this emulation has an (unavoidable) race. Two, I think pselect() will deliver the signal in addition to returning, which we want to avoid. Not sure about this though. -- error compiling committee.c: too many arguments to function ------------------------------------------------------------------------- This SF.net email is sponsored by the 2008 JavaOne(SM) Conference Don't miss this year's exciting event. There's still time to save $100. Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone