[PATCH 6/6] mm: remove some update_mmu_cache() calls

[Peter Zijlstra]

From: Christoph Lameter <clameter@xxxxxxx>

This may be a bit controversial but it does not seem to
make sense to use the update_mmu_cache macro when we reuse
the page. We are only fiddling around with the protections,
the dirty and accessed bits.

With the call to update_mmu_cache the way of using the macros
would be different from mprotect() and page_mkclean(). I'd
rather have everything work the same way. If this breaks on some
arches then also mprotect and page_mkclean() are broken.
The use of mprotect() is rare, we may have breakage in some
arches that we just have not seen yet.

Signed-off-by: Christoph Lameter <clameter@xxxxxxx>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
---
 mm/memory.c |    2 --
 1 file changed, 2 deletions(-)

Index: 2.6-mm/mm/memory.c
===================================================================
--- 2.6-mm.orig/mm/memory.c	2006-06-19 16:21:16.000000000 +0200
+++ 2.6-mm/mm/memory.c	2006-06-19 16:21:25.000000000 +0200
@@ -1514,7 +1514,6 @@ static int do_wp_page(struct mm_struct *
 		entry = pte_mkyoung(orig_pte);
 		entry = maybe_mkwrite(pte_mkdirty(entry), vma);
 		ptep_set_access_flags(vma, address, page_table, entry, 1);
-		update_mmu_cache(vma, address, entry);
 		lazy_mmu_prot_update(entry);
 		ret |= VM_FAULT_WRITE;
 		goto unlock;
@@ -2317,7 +2316,6 @@ static inline int handle_pte_fault(struc
 	entry = pte_mkyoung(entry);
 	if (!pte_same(old_entry, entry)) {
 		ptep_set_access_flags(vma, address, pte, entry, write_access);
-		update_mmu_cache(vma, address, entry);
 		lazy_mmu_prot_update(entry);
 	} else {
 		/*
-
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