From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56409) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aOfuy-0007V2-CK for qemu-devel@nongnu.org; Thu, 28 Jan 2016 01:18:57 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aOfuu-0003bQ-62 for qemu-devel@nongnu.org; Thu, 28 Jan 2016 01:18:56 -0500 Date: Thu, 28 Jan 2016 16:57:28 +1100 From: David Gibson Message-ID: <20160128055728.GC23043@voom.redhat.com> References: <1453889591-30968-1-git-send-email-david@gibson.dropbear.id.au> <1453889591-30968-9-git-send-email-david@gibson.dropbear.id.au> <1453955598.3148.55.camel@kernel.crashing.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="9Ek0hoCL9XbhcSqy" Content-Disposition: inline In-Reply-To: <1453955598.3148.55.camel@kernel.crashing.org> Subject: Re: [Qemu-devel] [PATCHv2 08/10] target-ppc: Add new TLB invalidate by HPTE call for hash64 MMUs List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Benjamin Herrenschmidt Cc: lvivier@redhat.com, thuth@redhat.com, aik@ozlabs.ru, agraf@suse.de, qemu-devel@nongnu.org, qemu-ppc@nongnu.org --9Ek0hoCL9XbhcSqy Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Jan 28, 2016 at 03:33:18PM +1100, Benjamin Herrenschmidt wrote: > On Wed, 2016-01-27 at 21:13 +1100, David Gibson wrote: > > When HPTEs are removed or modified by hypercalls on spapr, we need to > > invalidate the relevant pages in the qemu TLB. > >=20 > > Currently we do that by doing some complicated calculations to work out= the > > right encoding for the tlbie instruction, then passing that to > > ppc_tlb_invalidate_one()... which totally ignores the argument and flus= hes > > the whole tlb. > >=20 > > Avoid that by adding a new flush-by-hpte helper in mmu-hash64.c. >=20 > Should we find a better "in between" so long run we implement tlbie > properly ? IE, tlbie will give us the page size using the same encoding > as the HPTE iirc when L=3D1 ? To be honest the encoding of tlbie in arch > 2.07 is so completely insane I have a hard time figuring it out myself > ... :-) I'm not entirely sure what the better in-between would be. Having the pagesize in tlbie isn't enough on its own - the bigger problem is that we need a way of invalidating a whole congruence class of entries in the qemu TLB, which it doesn't currently provide a means to do. > Otherwise, >=20 > Acked-by: Benjamin Herrenschmidt --=20 David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson --9Ek0hoCL9XbhcSqy Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJWqa3IAAoJEGw4ysog2bOSKLEP/1+MwwG+LmQvPKo+xYZHLQ6o c+QczixQpP0flyGQnHPvZkG4IleXEykURenCj5snGMGrPuNj5JhrxUItUs3OSJ0r vg3LWct0gzWzj6UGRuCIqVgMhFPxKQweQK61muMIkj40Tz9ldgR2CnQhP6rhsMQs 7BIso8YJcfoLGqaTvJeeORMYH/+UttQGuXJ9mCtDfd4GUgKUxTVVd1FPcwEh1HNK yfSZOEapnEEYFVlJ7iAhOXbn0+eGCr4Fvi64EfAX1e9nyz8PwSA6cZgh81zSE468 7dSVMyrgjdDkcCxImD+m0Jz+MEjNSSVqwRSPttQ9lufa97G88ubDtUmzCSVX8EtK W/J8JOyG52XjpGKmvHnQO10HzeEMgBGznGX8VHfJuk6H0ebderqPrTKWqG/ezTWT pdDeHRmjamTu0Y/7N0ogHHjVllBiohnJlLX2/0dUx6wrDy6ge6pxaIEyZcNdq7A2 QQtgtbleK4XVz7rR3ZP8Rmw4h7H+HRAO2swRa+Ps2QV65pW1LchwemwUo39fsWns p2z3u6Rt0hJR4d+LvZrIKdZSRNU9Z63XYLdoWT+Z6I4GhVxulkw4BVzhWpcGXgFV Rl/yZCZSWy+Kzgk0kxx4Z2hldRIar+a25mirpSpr5GISzjHv8pvlGbPPSMEc2edj Y84aPPiqzSE6I99dxgAq =wY+s -----END PGP SIGNATURE----- --9Ek0hoCL9XbhcSqy--