From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1NJuW7-0003kp-Ul for qemu-devel@nongnu.org; Sun, 13 Dec 2009 14:54:07 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1NJuW5-0003kR-OD for qemu-devel@nongnu.org; Sun, 13 Dec 2009 14:54:07 -0500 Received: from [199.232.76.173] (port=34898 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NJuW5-0003kI-MG for qemu-devel@nongnu.org; Sun, 13 Dec 2009 14:54:05 -0500 Received: from are.twiddle.net ([75.149.56.221]:60634) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1NJuW5-00030i-7z for qemu-devel@nongnu.org; Sun, 13 Dec 2009 14:54:05 -0500 Message-ID: <4B25465A.8090002@twiddle.net> Date: Sun, 13 Dec 2009 11:54:02 -0800 From: Richard Henderson MIME-Version: 1.0 Subject: Re: [Qemu-devel] [PATCH 1/7] alpha: Implement IMB; add placeholders for other userspace PALcalls. References: <20091213192815.GB4281@volta.aurel32.net> In-Reply-To: <20091213192815.GB4281@volta.aurel32.net> Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Aurelien Jarno Cc: qemu-devel@nongnu.org On 12/13/2009 11:28 AM, Aurelien Jarno wrote: > Is it really necessary to flush all the TB here? QEMU should already > discard TB that have been modified. No. But I meant to look into this more carefully with a view to disabling the other checking within QEMU and speed things up a tad. It seems to me that the explicit checking with each memory write ought to only be necessary on architectures like x86 that don't architecturally require a flush insn to be used. I can drop this fragment if necessary for patch acceptance, however. r~