[PATCH 2/8] ppc/hugetlbfs: Replace ACCESS_ONCE with READ_ONCE

2015-01-15 Thread Christian Borntraeger
ACCESS_ONCE does not work reliably on non-scalar types. For
example gcc 4.6 and 4.7 might remove the volatile tag for such
accesses during the SRA (scalar replacement of aggregates) step
(https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145)

Change the ppc/hugetlbfs code to replace ACCESS_ONCE with READ_ONCE.

Signed-off-by: Christian Borntraeger 
---
 arch/powerpc/mm/hugetlbpage.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index 5ff4e07..620d0ec 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -978,7 +978,7 @@ pte_t *find_linux_pte_or_hugepte(pgd_t *pgdir, unsigned 
long ea, unsigned *shift
 */
pdshift = PUD_SHIFT;
pudp = pud_offset(, ea);
-   pud  = ACCESS_ONCE(*pudp);
+   pud  = READ_ONCE(*pudp);
 
if (pud_none(pud))
return NULL;
@@ -990,7 +990,7 @@ pte_t *find_linux_pte_or_hugepte(pgd_t *pgdir, unsigned 
long ea, unsigned *shift
else {
pdshift = PMD_SHIFT;
pmdp = pmd_offset(, ea);
-   pmd  = ACCESS_ONCE(*pmdp);
+   pmd  = READ_ONCE(*pmdp);
/*
 * A hugepage collapse is captured by pmd_none, because
 * it mark the pmd none and do a hpte invalidate.
-- 
1.9.3

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[PATCH 2/8] ppc/hugetlbfs: Replace ACCESS_ONCE with READ_ONCE

2015-01-15 Thread Christian Borntraeger
ACCESS_ONCE does not work reliably on non-scalar types. For
example gcc 4.6 and 4.7 might remove the volatile tag for such
accesses during the SRA (scalar replacement of aggregates) step
(https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145)

Change the ppc/hugetlbfs code to replace ACCESS_ONCE with READ_ONCE.

Signed-off-by: Christian Borntraeger borntrae...@de.ibm.com
---
 arch/powerpc/mm/hugetlbpage.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index 5ff4e07..620d0ec 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -978,7 +978,7 @@ pte_t *find_linux_pte_or_hugepte(pgd_t *pgdir, unsigned 
long ea, unsigned *shift
 */
pdshift = PUD_SHIFT;
pudp = pud_offset(pgd, ea);
-   pud  = ACCESS_ONCE(*pudp);
+   pud  = READ_ONCE(*pudp);
 
if (pud_none(pud))
return NULL;
@@ -990,7 +990,7 @@ pte_t *find_linux_pte_or_hugepte(pgd_t *pgdir, unsigned 
long ea, unsigned *shift
else {
pdshift = PMD_SHIFT;
pmdp = pmd_offset(pud, ea);
-   pmd  = ACCESS_ONCE(*pmdp);
+   pmd  = READ_ONCE(*pmdp);
/*
 * A hugepage collapse is captured by pmd_none, because
 * it mark the pmd none and do a hpte invalidate.
-- 
1.9.3

--
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the body of a message to majord...@vger.kernel.org
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Please read the FAQ at  http://www.tux.org/lkml/