[PATCH] xfs: simplify kmem_{zone_}zalloc

[Gu Zheng <guz.fnst@cn.fujitsu.com>]

Introduce flag KM_ZERO which is used to alloc zeroed entry, and convert
kmem_{zone_}zalloc to call kmem_{zone_}alloc() with KM_ZERO directly,
in order to avoid the setting to zero step.


Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
---
 fs/xfs/kmem.c |   14 ++------------
 fs/xfs/kmem.h |    7 ++++++-
 2 files changed, 8 insertions(+), 13 deletions(-)

diff --git a/fs/xfs/kmem.c b/fs/xfs/kmem.c
index a02cfb9..d56fcc9 100644
--- a/fs/xfs/kmem.c
+++ b/fs/xfs/kmem.c
@@ -65,12 +65,7 @@ kmem_alloc(size_t size, xfs_km_flags_t flags)
 void *
 kmem_zalloc(size_t size, xfs_km_flags_t flags)
 {
-	void	*ptr;
-
-	ptr = kmem_alloc(size, flags);
-	if (ptr)
-		memset((char *)ptr, 0, (int)size);
-	return ptr;
+	return kmem_alloc(size, flags | KM_ZERO);
 }
 
 void *
@@ -132,10 +127,5 @@ kmem_zone_alloc(kmem_zone_t *zone, xfs_km_flags_t flags)
 void *
 kmem_zone_zalloc(kmem_zone_t *zone, xfs_km_flags_t flags)
 {
-	void	*ptr;
-
-	ptr = kmem_zone_alloc(zone, flags);
-	if (ptr)
-		memset((char *)ptr, 0, kmem_cache_size(zone));
-	return ptr;
+	return kmem_zone_alloc(zone, flags | KM_ZERO);
 }
diff --git a/fs/xfs/kmem.h b/fs/xfs/kmem.h
index 3a7371c..8ea21fd 100644
--- a/fs/xfs/kmem.h
+++ b/fs/xfs/kmem.h
@@ -32,6 +32,7 @@ typedef unsigned __bitwise xfs_km_flags_t;
 #define KM_NOSLEEP	((__force xfs_km_flags_t)0x0002u)
 #define KM_NOFS		((__force xfs_km_flags_t)0x0004u)
 #define KM_MAYFAIL	((__force xfs_km_flags_t)0x0008u)
+#define KM_ZERO		((__force xfs_km_flags_t)0x0010u)
 
 /*
  * We use a special process flag to avoid recursive callbacks into
@@ -43,7 +44,7 @@ kmem_flags_convert(xfs_km_flags_t flags)
 {
 	gfp_t	lflags;
 
-	BUG_ON(flags & ~(KM_SLEEP|KM_NOSLEEP|KM_NOFS|KM_MAYFAIL));
+	BUG_ON(flags & ~(KM_SLEEP|KM_NOSLEEP|KM_NOFS|KM_MAYFAIL|KM_ZERO));
 
 	if (flags & KM_NOSLEEP) {
 		lflags = GFP_ATOMIC | __GFP_NOWARN;
@@ -52,6 +53,10 @@ kmem_flags_convert(xfs_km_flags_t flags)
 		if ((current->flags & PF_FSTRANS) || (flags & KM_NOFS))
 			lflags &= ~__GFP_FS;
 	}
+
+	if (flags & KM_ZERO)
+		lflags |= __GFP_ZERO;
+
 	return lflags;
 }
 
-- 
1.7.7