mm: x86 pgtable: require X86_64 for soft-dirty tracker
authorCyrill Gorcunov <gorcunov@openvz.org>
Wed, 4 Jun 2014 23:08:16 +0000 (16:08 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Wed, 4 Jun 2014 23:54:05 +0000 (16:54 -0700)
commit2bf01f9f0cf07b231c90e5d56266e84fe17cec79
tree17b0a78d5270dc6d341dace4c2a0b80051a4f003
parent2373eaecff33db5972bde9418f92d6401b4a945c
mm: x86 pgtable: require X86_64 for soft-dirty tracker

Tracking dirty status on 2 level pages requires very ugly macros and
taking into account how old the machines who can operate without PAE
mode only are, lets drop soft dirty tracker from them for code
simplicity (note I can't drop all the macros from 2 level pages by now
since _PAGE_BIT_PROTNONE and _PAGE_BIT_FILE are still used even without
tracker).

Linus proposed to completely rip off softdirty support on x86-32 (even
with PAE) and since for CRIU we're not planning to support native x86-32
mode, lets do that.

(Softdirty tracker is relatively new feature which is mostly used by
CRIU so I don't expect if such API change would cause problems for
userspace).

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Steven Noonan <steven@uplinklabs.net>
Cc: Rik van Riel <riel@redhat.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
arch/x86/Kconfig
arch/x86/include/asm/pgtable-2level.h
arch/x86/include/asm/pgtable.h