From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E587BC6FA82 for ; Fri, 23 Sep 2022 12:22:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229727AbiIWMWK (ORCPT ); Fri, 23 Sep 2022 08:22:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41600 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230460AbiIWMUg (ORCPT ); Fri, 23 Sep 2022 08:20:36 -0400 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 13BB7140198 for ; Fri, 23 Sep 2022 05:12:07 -0700 (PDT) Received: from gallifrey.ext.pengutronix.de ([2001:67c:670:201:5054:ff:fe8d:eefb] helo=bjornoya.blackshift.org) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1obhXH-0008U9-3p; Fri, 23 Sep 2022 14:12:03 +0200 Received: from pengutronix.de (unknown [IPv6:2a01:4f8:1c1c:29e9:22:41ff:fe00:1400]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) (Authenticated sender: mkl-all@blackshift.org) by smtp.blackshift.org (Postfix) with ESMTPSA id 2384FEB19E; Fri, 23 Sep 2022 12:12:02 +0000 (UTC) Date: Fri, 23 Sep 2022 14:12:01 +0200 From: Marc Kleine-Budde To: Rhett Aultman Cc: linux-can@vger.kernel.org, Vasanth Sadhasivan Subject: Re: [PATCH v2] can: gs_usb: remove dma allocations Message-ID: <20220923121201.f5rllcey7enwss4e@pengutronix.de> References: <20220913204110.89730-1-rhett.aultman@samsara.com> <20220920154724.861093-1-rhett.aultman@samsara.com> <20220920154724.861093-2-rhett.aultman@samsara.com> <20220923121110.luq5xwrlflgstlku@pengutronix.de> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="mcfucuaab5fxawj3" Content-Disposition: inline In-Reply-To: <20220923121110.luq5xwrlflgstlku@pengutronix.de> X-SA-Exim-Connect-IP: 2001:67c:670:201:5054:ff:fe8d:eefb X-SA-Exim-Mail-From: mkl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-can@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-can@vger.kernel.org --mcfucuaab5fxawj3 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On 23.09.2022 14:11:11, Marc Kleine-Budde wrote: > On 20.09.2022 11:47:24, Rhett Aultman wrote: > > From: Vasanth Sadhasivan > >=20 > > DMA allocated buffers are a precious resource. If there is no need for = DMA=20 > > allocations, then it might be worth to use non-dma allocated buffers.= =20 > > After testing the gs_usb driver with and without DMA allocation, there= =20 > > does not seem to be a significant change in latency or cpu utilization= =20 > > either way. Therefore, DMA allocation is not necessary and removed.=20 > > Internal buffers used within urbs were managed and freed manually. Thes= e=20 > > buffers are no longer needed to be managed by the driver. The=20 > > URB_FREE_BUFFER flag, allows for the buffers in question to=20 > > be automatically freed. > >=20 > > Co-developed-by: Rhett Aultman > > Signed-off-by: Rhett Aultman > > Signed-off-by: Vasanth Sadhasivan >=20 > Applied to linux-can. linux-can-next that is. Marc --=20 Pengutronix e.K. | Marc Kleine-Budde | Embedded Linux | https://www.pengutronix.de | Vertretung West/Dortmund | Phone: +49-231-2826-924 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | --mcfucuaab5fxawj3 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEBsvAIBsPu6mG7thcrX5LkNig010FAmMtoo8ACgkQrX5LkNig 013HIggAhxMvA/o0jfgXYdzlzA5qqB4zP0NUpdqByvfFdFSlSoLGgnJF98l+SLp+ R3KXKl0FLDK9pVsuhizhED56pijjjzKqmng1bKQrqT1DhzaN+MGdy8N/1qpswS92 nAPExI9V5WEPUrKiSmymRrkiC82aij3lfDG0k4fu99a+0pMOQenZoy8d3pYqoeX5 Ixebzfdav6bk6dmMAn4H2S/wOsFYNESRoZxw747x0arnOB4xPgzeCcbGkNVguZ5C YyTvAtbXh08v8Gea5CqUAFF4W1weUdeVavr1wf7wYpR7k5J6CqcD/0gEIx9Q9UKq Ry+XtNdZdEmUuI7bBbF0IHMrPXn7kA== =q8kS -----END PGP SIGNATURE----- --mcfucuaab5fxawj3--