]> git.proxmox.com Git - mirror_ubuntu-kernels.git/commit
x86/mm: provide pmdp_establish() helper
authorKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Thu, 1 Feb 2018 00:18:13 +0000 (16:18 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 1 Feb 2018 01:18:38 +0000 (17:18 -0800)
commit86fa949b050184ffc53688516a6a83ae5f98d08a
tree58d1c3e2704aa32706c528afd6030a70de60ae15
parenta8e654f01cb725d0bfd741ebca1bf4c9337969cc
x86/mm: provide pmdp_establish() helper

We need an atomic way to setup pmd page table entry, avoiding races with
CPU setting dirty/accessed bits.  This is required to implement
pmdp_invalidate() that doesn't lose these bits.

On PAE we can avoid expensive cmpxchg8b for cases when new page table
entry is not present.  If it's present, fallback to cpmxchg loop.

[akpm@linux-foundation.org: add missing `do' to do-while loop]
Link: http://lkml.kernel.org/r/20171213105756.69879-10-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
arch/x86/include/asm/pgtable-3level.h
arch/x86/include/asm/pgtable.h