diff mbox series

[1/4] xfs: Remove kmem_zone_alloc() usage

Message ID 20200708125608.155645-2-cmaiolino@redhat.com (mailing list archive)
State Superseded
Headers show
Series Continue xfs kmem cleanup | expand

Commit Message

Carlos Maiolino July 8, 2020, 12:56 p.m. UTC
Use kmem_cache_alloc() directly.

All kmem_zone_alloc() users pass 0 as flags, which are translated into:
GFP_KERNEL | __GFP_NOWARN, and kmem_zone_alloc() loops forever until the
allocation succeeds.

So, call kmem_cache_alloc() with __GFP_NOFAIL directly. which will have
the same result.

Once allocation will never fail, don't bother to add __GFP_NOWARN.

Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
---
 fs/xfs/libxfs/xfs_alloc.c |  3 ++-
 fs/xfs/libxfs/xfs_bmap.c  |  3 ++-
 fs/xfs/xfs_icache.c       | 11 +++--------
 3 files changed, 7 insertions(+), 10 deletions(-)

Comments

Dave Chinner July 9, 2020, 2:45 a.m. UTC | #1
On Wed, Jul 08, 2020 at 02:56:05PM +0200, Carlos Maiolino wrote:
> Use kmem_cache_alloc() directly.
> 
> All kmem_zone_alloc() users pass 0 as flags, which are translated into:
> GFP_KERNEL | __GFP_NOWARN, and kmem_zone_alloc() loops forever until the
> allocation succeeds.
> 
> So, call kmem_cache_alloc() with __GFP_NOFAIL directly. which will have
> the same result.
> 
> Once allocation will never fail, don't bother to add __GFP_NOWARN.

Last two paragraphs are a little odd. Maybe:

We can use __GFP_NOFAIL to tell the allocator to loop forever rather
than doing it ourself, and because the allocation will never fail we
do not need to use __GFP_NOWARN anymore. Hence all callers can be
converted to use GFP_KERNEL | __GFP_NOFAIL.


> Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
> ---
>  fs/xfs/libxfs/xfs_alloc.c |  3 ++-
>  fs/xfs/libxfs/xfs_bmap.c  |  3 ++-
>  fs/xfs/xfs_icache.c       | 11 +++--------
>  3 files changed, 7 insertions(+), 10 deletions(-)
> 
> @@ -36,14 +36,9 @@ xfs_inode_alloc(
>  {
>  	struct xfs_inode	*ip;
>  
> -	/*
> -	 * if this didn't occur in transactions, we could use
> -	 * KM_MAYFAIL and return NULL here on ENOMEM. Set the
> -	 * code up to do this anyway.
> -	 */
> -	ip = kmem_zone_alloc(xfs_inode_zone, 0);
> -	if (!ip)
> -		return NULL;
> +	ip = kmem_cache_alloc(xfs_inode_zone,
> +			      GFP_KERNEL | __GFP_NOFAIL);
> +

Hmmmm. We really should check PF_FSTRANS here for the flags we
should be setting. Something like:

	gfp_t		gfp_mask = GFP_KERNEL;

	if (current->flags & PF_FSTRANS)
		gfp_mask |= __GFP_NOFAIL;

	ip = kmem_cache_alloc(xfs_inode_zone, gfp_mask);
	if (!ip)
		return NULL;

Cheers,

Dave.
diff mbox series

Patch

diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c
index 203e74fa64aa6..583242253c027 100644
--- a/fs/xfs/libxfs/xfs_alloc.c
+++ b/fs/xfs/libxfs/xfs_alloc.c
@@ -2467,7 +2467,8 @@  xfs_defer_agfl_block(
 	ASSERT(xfs_bmap_free_item_zone != NULL);
 	ASSERT(oinfo != NULL);
 
-	new = kmem_zone_alloc(xfs_bmap_free_item_zone, 0);
+	new = kmem_cache_alloc(xfs_bmap_free_item_zone,
+			       GFP_KERNEL | __GFP_NOFAIL);
 	new->xefi_startblock = XFS_AGB_TO_FSB(mp, agno, agbno);
 	new->xefi_blockcount = 1;
 	new->xefi_oinfo = *oinfo;
diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
index 667cdd0dfdf4a..fd5c0d669d0d7 100644
--- a/fs/xfs/libxfs/xfs_bmap.c
+++ b/fs/xfs/libxfs/xfs_bmap.c
@@ -553,7 +553,8 @@  __xfs_bmap_add_free(
 #endif
 	ASSERT(xfs_bmap_free_item_zone != NULL);
 
-	new = kmem_zone_alloc(xfs_bmap_free_item_zone, 0);
+	new = kmem_cache_alloc(xfs_bmap_free_item_zone,
+			       GFP_KERNEL | __GFP_NOFAIL);
 	new->xefi_startblock = bno;
 	new->xefi_blockcount = (xfs_extlen_t)len;
 	if (oinfo)
diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c
index 5daef654956cb..69f887abe4334 100644
--- a/fs/xfs/xfs_icache.c
+++ b/fs/xfs/xfs_icache.c
@@ -36,14 +36,9 @@  xfs_inode_alloc(
 {
 	struct xfs_inode	*ip;
 
-	/*
-	 * if this didn't occur in transactions, we could use
-	 * KM_MAYFAIL and return NULL here on ENOMEM. Set the
-	 * code up to do this anyway.
-	 */
-	ip = kmem_zone_alloc(xfs_inode_zone, 0);
-	if (!ip)
-		return NULL;
+	ip = kmem_cache_alloc(xfs_inode_zone,
+			      GFP_KERNEL | __GFP_NOFAIL);
+
 	if (inode_init_always(mp->m_super, VFS_I(ip))) {
 		kmem_cache_free(xfs_inode_zone, ip);
 		return NULL;