From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752595AbbIKK3I (ORCPT ); Fri, 11 Sep 2015 06:29:08 -0400 Received: from mezzanine.sirena.org.uk ([106.187.55.193]:59795 "EHLO mezzanine.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751472AbbIKK3F (ORCPT ); Fri, 11 Sep 2015 06:29:05 -0400 Date: Fri, 11 Sep 2015 11:28:58 +0100 From: Mark Brown To: Stephen Boyd Cc: linux-kernel@vger.kernel.org Message-ID: <20150911102858.GE12027@sirena.org.uk> References: <1441913221-19622-1-git-send-email-sboyd@codeaurora.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="jdUL6/HigZDKqWIo" Content-Disposition: inline In-Reply-To: <1441913221-19622-1-git-send-email-sboyd@codeaurora.org> X-Cookie: You are fairminded, just and loving. User-Agent: Mutt/1.5.23 (2014-03-12) X-SA-Exim-Connect-IP: 94.175.94.161 X-SA-Exim-Mail-From: broonie@sirena.org.uk Subject: Re: [PATCH] regmap: Allocate buffers with GFP_ATOMIC when fast_io == true X-SA-Exim-Version: 4.2.1 (built Mon, 26 Dec 2011 16:24:06 +0000) X-SA-Exim-Scanned: Yes (on mezzanine.sirena.org.uk) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --jdUL6/HigZDKqWIo Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Thu, Sep 10, 2015 at 12:27:01PM -0700, Stephen Boyd wrote: > If a regmap is using fast_io, allocate buffers in the write APIs > with GFP_ATOMIC instead of GFP_KERNEL. Otherwise we may schedule > while atomic. Why is this needed? If something needs fast I/O it probably doesn't want to be going down any of the code paths that result in us doing allocations. I'd expect either no cache, a flat cache or setting up defaults at initialisation time. --jdUL6/HigZDKqWIo Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQEcBAEBCAAGBQJV8qzpAAoJECTWi3JdVIfQXekIAIMSSDtbpz+c9ELHOcwnHmmP RBo57BZOVwg+bFvWpAay3bCyrgpNwsyz08IpSYcUeV7YDLTNyQGNnUqiS33BYCxW yJD81HHDxbbfpgmB+DhXfce+C/z3Jql3zX09dGKWh6tPODdxsgNs/jpfb3TcDd9y 1Le+nrZzbSMgfd8ZZ217JQLbkmYO2FSLM+qpsi+sC0hZWoGOrCFb2y01pkeiSkwC MD56qwOozqZPCdYgkY2t1LY5JtX0fHr6N23u2gcP2DK0N+TEj5M2lh0KV/I6HGvG NPPQmD6EehQKyw0uIZsMixGWiF7mFjjfh3O99fG6/eCCNe5520gXrVXucUnI5Gs= =fp5z -----END PGP SIGNATURE----- --jdUL6/HigZDKqWIo--