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Date: Tue, 13 Jan 2015 17:37:52 +0100
From: Andrea Arcangeli <aarcange@...hat.com>
To: Andrew Morton <akpm@...ux-foundation.org>,
linux-kernel@...r.kernel.org, linux-mm@...ck.org
Cc: "Kirill A. Shutemov" <kirill@...temov.name>,
Michel Lespinasse <walken@...gle.com>,
Andrew Jones <drjones@...hat.com>,
Hugh Dickins <hughd@...gle.com>, Mel Gorman <mgorman@...e.de>,
Andres Lagar-Cavilla <andreslc@...gle.com>,
Minchan Kim <minchan@...nel.org>,
KOSAKI Motohiro <kosaki.motohiro@...il.com>,
"\\\"Dr. David Alan Gilbert\\\"" <dgilbert@...hat.com>,
Peter Feiner <pfeiner@...gle.com>,
Peter Zijlstra <peterz@...radead.org>,
Benjamin Herrenschmidt <benh@...nel.crashing.org>,
James Bottomley <James.Bottomley@...senPartnership.com>,
David Miller <davem@...emloft.net>,
Steve Capper <steve.capper@...aro.org>,
Johannes Weiner <jweiner@...hat.com>
Subject: [PATCH 3/5] mm: gup: use get_user_pages_unlocked within get_user_pages_fast
This allows the get_user_pages_fast slow path to release the mmap_sem
before blocking.
Signed-off-by: Andrea Arcangeli <aarcange@...hat.com>
---
arch/mips/mm/gup.c | 8 +++-----
arch/s390/mm/gup.c | 6 ++----
arch/sh/mm/gup.c | 6 ++----
arch/sparc/mm/gup.c | 6 ++----
arch/x86/mm/gup.c | 7 +++----
mm/gup.c | 6 ++----
mm/util.c | 10 ++--------
7 files changed, 16 insertions(+), 33 deletions(-)
diff --git a/arch/mips/mm/gup.c b/arch/mips/mm/gup.c
index 70795a6..349995d 100644
--- a/arch/mips/mm/gup.c
+++ b/arch/mips/mm/gup.c
@@ -301,11 +301,9 @@ slow_irqon:
start += nr << PAGE_SHIFT;
pages += nr;
- down_read(&mm->mmap_sem);
- ret = get_user_pages(current, mm, start,
- (end - start) >> PAGE_SHIFT,
- write, 0, pages, NULL);
- up_read(&mm->mmap_sem);
+ ret = get_user_pages_unlocked(current, mm, start,
+ (end - start) >> PAGE_SHIFT,
+ write, 0, pages);
/* Have to be a bit careful with return values */
if (nr > 0) {
diff --git a/arch/s390/mm/gup.c b/arch/s390/mm/gup.c
index 639fce46..5c586c7 100644
--- a/arch/s390/mm/gup.c
+++ b/arch/s390/mm/gup.c
@@ -235,10 +235,8 @@ int get_user_pages_fast(unsigned long start, int nr_pages, int write,
/* Try to get the remaining pages with get_user_pages */
start += nr << PAGE_SHIFT;
pages += nr;
- down_read(&mm->mmap_sem);
- ret = get_user_pages(current, mm, start,
- nr_pages - nr, write, 0, pages, NULL);
- up_read(&mm->mmap_sem);
+ ret = get_user_pages_unlocked(current, mm, start,
+ nr_pages - nr, write, 0, pages);
/* Have to be a bit careful with return values */
if (nr > 0)
ret = (ret < 0) ? nr : ret + nr;
diff --git a/arch/sh/mm/gup.c b/arch/sh/mm/gup.c
index 37458f3..e15f52a 100644
--- a/arch/sh/mm/gup.c
+++ b/arch/sh/mm/gup.c
@@ -257,10 +257,8 @@ slow_irqon:
start += nr << PAGE_SHIFT;
pages += nr;
- down_read(&mm->mmap_sem);
- ret = get_user_pages(current, mm, start,
- (end - start) >> PAGE_SHIFT, write, 0, pages, NULL);
- up_read(&mm->mmap_sem);
+ ret = get_user_pages_unlocked(current, mm, start,
+ (end - start) >> PAGE_SHIFT, write, 0, pages);
/* Have to be a bit careful with return values */
if (nr > 0) {
diff --git a/arch/sparc/mm/gup.c b/arch/sparc/mm/gup.c
index ae6ce38..2e5c4fc 100644
--- a/arch/sparc/mm/gup.c
+++ b/arch/sparc/mm/gup.c
@@ -249,10 +249,8 @@ slow:
start += nr << PAGE_SHIFT;
pages += nr;
- down_read(&mm->mmap_sem);
- ret = get_user_pages(current, mm, start,
- (end - start) >> PAGE_SHIFT, write, 0, pages, NULL);
- up_read(&mm->mmap_sem);
+ ret = get_user_pages_unlocked(current, mm, start,
+ (end - start) >> PAGE_SHIFT, write, 0, pages);
/* Have to be a bit careful with return values */
if (nr > 0) {
diff --git a/arch/x86/mm/gup.c b/arch/x86/mm/gup.c
index d754782..4548dd8 100644
--- a/arch/x86/mm/gup.c
+++ b/arch/x86/mm/gup.c
@@ -388,10 +388,9 @@ slow_irqon:
start += nr << PAGE_SHIFT;
pages += nr;
- down_read(&mm->mmap_sem);
- ret = get_user_pages(current, mm, start,
- (end - start) >> PAGE_SHIFT, write, 0, pages, NULL);
- up_read(&mm->mmap_sem);
+ ret = get_user_pages_unlocked(current, mm, start,
+ (end - start) >> PAGE_SHIFT,
+ write, 0, pages);
/* Have to be a bit careful with return values */
if (nr > 0) {
diff --git a/mm/gup.c b/mm/gup.c
index d616811..da200a1 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -1252,10 +1252,8 @@ int get_user_pages_fast(unsigned long start, int nr_pages, int write,
start += nr << PAGE_SHIFT;
pages += nr;
- down_read(&mm->mmap_sem);
- ret = get_user_pages(current, mm, start,
- nr_pages - nr, write, 0, pages, NULL);
- up_read(&mm->mmap_sem);
+ ret = get_user_pages_unlocked(current, mm, start,
+ nr_pages - nr, write, 0, pages);
/* Have to be a bit careful with return values */
if (nr > 0) {
diff --git a/mm/util.c b/mm/util.c
index fec39d4..f3ef639 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -240,14 +240,8 @@ int __weak get_user_pages_fast(unsigned long start,
int nr_pages, int write, struct page **pages)
{
struct mm_struct *mm = current->mm;
- int ret;
-
- down_read(&mm->mmap_sem);
- ret = get_user_pages(current, mm, start, nr_pages,
- write, 0, pages, NULL);
- up_read(&mm->mmap_sem);
-
- return ret;
+ return get_user_pages_unlocked(current, mm, start, nr_pages,
+ write, 0, pages);
}
EXPORT_SYMBOL_GPL(get_user_pages_fast);
--
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