projects/linux·commit d6f8bb13

i386 mm: use pte_update() in ptep_test_and_clear_dirty()

d6f8bb13 · Hugh Dickins <[email protected]> · 2007-06-16 10:15:59 -07:00

It is not safe to use pte_update_defer() in ptep_test_and_clear_young():
its only user, /proc/<pid>/clear_refs, drops pte lock before flushing TLB.
Use the safe though less efficient pte_update() paravirtop in its place.
Likewise in ptep_test_and_clear_dirty(), though that has no current use.

These are macros (header file dependency stops them from becoming inline
functions), so be more liberal with the underscores and parentheses.

Signed-off-by: Hugh Dickins <[email protected]>
Cc: Zachary Amsden <[email protected]>
Cc: David Rientjes <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Commit
d6f8bb1310d4745ff1d0c74eeacae31e2a3eeff1
Parents
30475cc1

Changes

1 files changed · +14 −12

FileStatusAddDelContent
include/asm-i386/pgtable.hmodified+14−12View file

include/asm-i386/pgtable.h

View file
diff --git a/include/asm-i386/pgtable.h b/include/asm-i386/pgtable.h
index 2394589..d62bdb0 100644
--- a/include/asm-i386/pgtable.h
+++ b/include/asm-i386/pgtable.h
@@ -295,22 +295,24 @@ do { \
#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_DIRTY
#define ptep_test_and_clear_dirty(vma, addr, ptep) ({ \
- int ret = 0; \
- if (pte_dirty(*ptep)) \
- ret = test_and_clear_bit(_PAGE_BIT_DIRTY, &ptep->pte_low); \
- if (ret) \
- pte_update_defer(vma->vm_mm, addr, ptep); \
- ret; \
+ int __ret = 0; \
+ if (pte_dirty(*(ptep))) \
+ __ret = test_and_clear_bit(_PAGE_BIT_DIRTY, \
+ &(ptep)->pte_low); \
+ if (__ret) \
+ pte_update((vma)->vm_mm, addr, ptep); \
+ __ret; \
})
#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
#define ptep_test_and_clear_young(vma, addr, ptep) ({ \
- int ret = 0; \
- if (pte_young(*ptep)) \
- ret = test_and_clear_bit(_PAGE_BIT_ACCESSED, &ptep->pte_low); \
- if (ret) \
- pte_update_defer(vma->vm_mm, addr, ptep); \
- ret; \
+ int __ret = 0; \
+ if (pte_young(*(ptep))) \
+ __ret = test_and_clear_bit(_PAGE_BIT_ACCESSED, \
+ &(ptep)->pte_low); \
+ if (__ret) \
+ pte_update((vma)->vm_mm, addr, ptep); \
+ __ret; \
})
/*