Commit e4a1cc56 authored Nov 06, 2012 by Rik van Riel Committed by Mel Gorman Dec 11, 2012

x86: mm: drop TLB flush from ptep_set_access_flags



Intel has an architectural guarantee that the TLB entry causing
a page fault gets invalidated automatically. This means
we should be able to drop the local TLB invalidation.

Because of the way other areas of the page fault code work,
chances are good that all x86 CPUs do this.  However, if
someone somewhere has an x86 CPU that does not invalidate
the TLB entry causing a page fault, this one-liner should
be easy to revert.

Signed-off-by: Rik van Riel <riel@redhat.com>
Cc: Linus Torvalds <torvalds@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michel Lespinasse <walken@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>

parent 0f9a921c

arch/x86/mm/pgtable.c

+0 −1

Original line number	Diff line number	Diff line
		@@ -317,7 +317,6 @@ int ptep_set_access_flags(struct vm_area_struct *vma,
		if (changed && dirty) {
		*ptep = entry;
		pte_update_defer(vma->vm_mm, address, ptep);
		__flush_tlb_one(address);
		}

		return changed;

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