Commit 252a6bf2 authored Feb 18, 2009 by Jeremy Fitzhardinge

mm: allow preemption in apply_to_pte_range



Impact: allow preemption in apply_to_pte_range updates to init_mm

Preemption is now allowed for lazy mmu mode, so don't disable
it for the inner loop of apply_to_pte_range.  This only applies
when doing updates to init_mm; user pagetables are still modified
under the pte lock, so preemption is disabled anyway.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>

parent 2829b449

mm/memory.c

+0 −2

Original line number	Diff line number	Diff line
		@@ -1718,7 +1718,6 @@ static int apply_to_pte_range(struct mm_struct mm, pmd_t pmd,

		BUG_ON(pmd_huge(*pmd));

		preempt_disable();
		arch_enter_lazy_mmu_mode();

		token = pmd_pgtable(*pmd);
		@@ -1730,7 +1729,6 @@ static int apply_to_pte_range(struct mm_struct mm, pmd_t pmd,
		} while (pte++, addr += PAGE_SIZE, addr != end);

		arch_leave_lazy_mmu_mode();
		preempt_enable();

		if (mm != &init_mm)
		pte_unmap_unlock(pte-1, ptl);

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