From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Subject: Re: [PATCH 0/2] eventfd: new EFD_STATE flag Date: Sun, 23 Aug 2009 18:51:10 +0200 Message-ID: <4A91737E.5080807@gnu.org> References: <20090820155655.GA8764@redhat.com> <4A8D8A28.2050004@redhat.com> <20090820175540.GA9232@redhat.com> <4A8D90BB.2030506@redhat.com> <20090820182847.GB9282@redhat.com> <4A913DA9.1020403@redhat.com> <20090823133620.GA12841@redhat.com> <4A9146E3.2090007@redhat.com> <20090823143021.GA27495@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Avi Kivity , Davide Libenzi , gleb@redhat.com, kvm@vger.kernel.org, Linux Kernel Mailing List To: "Michael S. Tsirkin" Return-path: In-Reply-To: <20090823143021.GA27495@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On 08/23/2009 04:30 PM, Michael S. Tsirkin wrote: > On Sun, Aug 23, 2009 at 04:40:51PM +0300, Avi Kivity wrote: >> On 08/23/2009 04:36 PM, Michael S. Tsirkin wrote: >>> More important here is realization that eventfd is a mutex/semaphore >>> implementation, not a generic event reporting interface as we are trying >>> to use it. >>> >> >> Well it is a generic event reporting interface (for example, aio uses it). > > Davide, I think it's a valid point. For example, what read on eventfd > does (zero a counter and return) is not like any semaphore I saw. It is similar to Win32 events (which can be used like contorted mutexes to sync two processes). Paolo