From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754199Ab0CCAN4 (ORCPT ); Tue, 2 Mar 2010 19:13:56 -0500 Received: from ozlabs.org ([203.10.76.45]:53869 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751884Ab0CCANz (ORCPT ); Tue, 2 Mar 2010 19:13:55 -0500 Subject: Re: [PATCH] powerpc: remove IOMMU_VMERGE config option From: Michael Ellerman Reply-To: michael@ellerman.id.au To: FUJITA Tomonori Cc: linuxppc-dev@ozlabs.org, linux-kernel@vger.kernel.org, benh@kernel.crashing.or, arnd@arndb.de, davem@davemloft.net In-Reply-To: <20100303085404R.fujita.tomonori@lab.ntt.co.jp> References: <20100303085404R.fujita.tomonori@lab.ntt.co.jp> Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-wpioZUw2UKI5VfpEQVHU" Date: Wed, 03 Mar 2010 11:13:52 +1100 Message-ID: <1267575232.7814.21.camel@concordia> Mime-Version: 1.0 X-Mailer: Evolution 2.28.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=-wpioZUw2UKI5VfpEQVHU Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Wed, 2010-03-03 at 08:54 +0900, FUJITA Tomonori wrote: > Seems that IOMMU_VMERGE option description gives the false > information: >=20 > http://marc.info/?l=3Dlinux-sparc&m=3D126753808727669&w=3D2 > http://marc.info/?l=3Dlinux-sparc&m=3D126753880528825&w=3D2 >=20 > IOMMU_VMERGE is unnecessary nowadays so how about removing it? Except you didn't remove it, you just made it uneditable? Why not get rid of it entirely. cheers > diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig > index 155d571..2dfa83b 100644 > --- a/arch/powerpc/Kconfig > +++ b/arch/powerpc/Kconfig > @@ -314,17 +314,8 @@ config 8XX_MINIMAL_FPEMU > It is recommended that you build a soft-float userspace instead. > =20 > config IOMMU_VMERGE > - bool "Enable IOMMU virtual merging" > + def_bool y > depends on PPC64 > - default y > - help > - Cause IO segments sent to a device for DMA to be merged virtually > - by the IOMMU when they happen to have been allocated contiguously. > - This doesn't add pressure to the IOMMU allocator. However, some > - drivers don't support getting large merged segments coming back > - from *_map_sg(). > - > - Most drivers don't have this problem; it is safe to say Y here. > =20 > config IOMMU_HELPER > def_bool PPC64 --=-wpioZUw2UKI5VfpEQVHU Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iEYEABECAAYFAkuNqboACgkQdSjSd0sB4dIQrwCfX8idcGbc4vLkHhYgq4Yn64Ul GloAn2ATMOaBvF7cbtEVTwCPOOLCNsnB =FP/9 -----END PGP SIGNATURE----- --=-wpioZUw2UKI5VfpEQVHU--