From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46920) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gDEuj-0004QA-Io for qemu-devel@nongnu.org; Thu, 18 Oct 2018 16:29:02 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gDEue-0002bI-4v for qemu-devel@nongnu.org; Thu, 18 Oct 2018 16:29:01 -0400 Received: from mail-sn1nam02on0116.outbound.protection.outlook.com ([104.47.36.116]:32476 helo=NAM02-SN1-obe.outbound.protection.outlook.com) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gDEud-0002Yg-V9 for qemu-devel@nongnu.org; Thu, 18 Oct 2018 16:28:56 -0400 From: Aaron Lindsay Date: Thu, 18 Oct 2018 20:28:53 +0000 Message-ID: <20181018202845.GI12691@quinoa.localdomain> References: <20181018182758.18646-1-richard.henderson@linaro.org> <20181018182758.18646-3-richard.henderson@linaro.org> In-Reply-To: <20181018182758.18646-3-richard.henderson@linaro.org> Content-Language: en-US Content-Type: text/plain; charset="us-ascii" Content-ID: <734CD0BF40626044B15D782E889DB3E1@prod.exchangelabs.com> Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: Re: [Qemu-devel] [PATCH 2/3] target/arm: Only flush tlb if ASID changes List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Richard Henderson Cc: "qemu-devel@nongnu.org" , "peter.maydell@linaro.org" On Oct 18 11:27, Richard Henderson wrote: > Since QEMU does not implement ASIDs, changes to the ASID must flush the > tlb. However, if the ASID does not change there is no reason to flush. >=20 > In testing a boot of the Ubuntu installer to the first menu, this reduces > the number of flushes by 30%, or nearly 600k instances. >=20 > Signed-off-by: Richard Henderson Reviewed-by: Aaron Lindsay