From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1NFRYx-0005Cz-9d for qemu-devel@nongnu.org; Tue, 01 Dec 2009 07:10:35 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1NFRYs-0005Bk-BI for qemu-devel@nongnu.org; Tue, 01 Dec 2009 07:10:34 -0500 Received: from [199.232.76.173] (port=51215 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NFRYs-0005Bf-4I for qemu-devel@nongnu.org; Tue, 01 Dec 2009 07:10:30 -0500 Received: from mx1.redhat.com ([209.132.183.28]:8328) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1NFRYr-0000ul-R9 for qemu-devel@nongnu.org; Tue, 01 Dec 2009 07:10:30 -0500 Message-ID: <4B1507AA.5050502@redhat.com> Date: Tue, 01 Dec 2009 14:10:18 +0200 From: Avi Kivity MIME-Version: 1.0 Subject: Re: [Qemu-devel] Re: [PATCH 0/7] KVM SMP support, early version References: <1259256300-23937-1-git-send-email-glommer@redhat.com> <4B12B042.9020409@web.de> <5d6222a80911300342x4d29653as6c23acac598dec64@mail.gmail.com> <5d6222a80911300755o4fed5447w9ddae1abaccf7100@mail.gmail.com> <4B13F570.4030605@redhat.com> <5d6222a80911300847w2faa9d39nb2fc6ee3ccb9ccfd@mail.gmail.com> <4B140141.1040708@siemens.com> In-Reply-To: <4B140141.1040708@siemens.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jan Kiszka Cc: Glauber Costa , Glauber Costa , qemu-devel@nongnu.org, aliguori@us.ibm.com On 11/30/2009 07:30 PM, Jan Kiszka wrote: >>> >>> No. But what's wrong with on_vcpu? >>> >> intrinsically racy. signal passing slow down things, etc. >> >> That said, as I've stated many times: I don't believe there's anything >> fundamentally wrong with on_vcpu. But we might get benefits from a re-design >> of things to avoid it whenever possible. (just like the vcpu_reset() >> I've just posted) >> >> > If you don't want immediate execution of update_guest_debug, save the > state that shall be transferred, set some flag, and run the transfer > before guest entry inside the vcpu threads (after putting the registers > as older kernels may otherwise overwrite the flags register). Should > work, may even avoid redundant calls during a gdb session. > There's no guarantee the vcpu will ever exit to qemu, so you have to signal the vcpu thread anyway. When you do that, you might as well load the new state. -- error compiling committee.c: too many arguments to function