Commit 68662f85 authored by Nicholas Piggin's avatar Nicholas Piggin Committed by Michael Ellerman
Browse files

powerpc/64s/radix: prefetch user address in update_mmu_cache 



Prefetch the faulting address in update_mmu_cache to give the page
table walker perhaps 100 cycles head start as locks are dropped and
the interrupt completed.

Signed-off-by: default avatarNicholas Piggin <npiggin@gmail.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
parent f569bd94

arch/powerpc/mm/mem.c

+3 −1
Original line number Diff line number Diff line
@@ -509,8 +509,10 @@ void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, 
	 */

	unsigned long access, trap;



	if (radix_enabled())

	if (radix_enabled()) {

		prefetch((void *)address);

		return;

	}



	/* We only want HPTEs for linux PTEs that have _PAGE_ACCESSED set */

	if (!pte_young(*ptep) || address >= TASK_SIZE)

arch/powerpc/mm/pgtable-book3s64.c

+2 −1
Original line number Diff line number Diff line
@@ -152,7 +152,8 @@ pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot) 
void update_mmu_cache_pmd(struct vm_area_struct *vma, unsigned long addr,

			  pmd_t *pmd)

{

	return;

	if (radix_enabled())

		prefetch((void *)addr);

}

#endif /* CONFIG_TRANSPARENT_HUGEPAGE */