On Wed, Nov 20, 2019 at 11:44:22AM +0100, Carlos Maiolino wrote:
> __GFP_NOFAIL can be used for an infinite retry + congestion_wait, so we
> can use kmem_cache_alloc() directly.
>
> Signed-off-by: Carlos Maiolino <cmaiolino@xxxxxxxxxx>
Looks ok,
Reviewed-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
--D
> ---
> V2:
> - Rephrase commit log to explain why it's ok to remove the retry
> loop from kmem_zone_alloc().
>
> fs/xfs/kmem.c | 21 ---------------------
> fs/xfs/kmem.h | 2 --
> fs/xfs/libxfs/xfs_alloc.c | 3 ++-
> fs/xfs/libxfs/xfs_bmap.c | 3 ++-
> fs/xfs/xfs_icache.c | 2 +-
> fs/xfs/xfs_trace.h | 1 -
> 6 files changed, 5 insertions(+), 27 deletions(-)
>
> diff --git a/fs/xfs/kmem.c b/fs/xfs/kmem.c
> index 1da94237a8cf..2644fdaa0549 100644
> --- a/fs/xfs/kmem.c
> +++ b/fs/xfs/kmem.c
> @@ -115,24 +115,3 @@ kmem_realloc(const void *old, size_t newsize, xfs_km_flags_t flags)
> congestion_wait(BLK_RW_ASYNC, HZ/50);
> } while (1);
> }
> -
> -void *
> -kmem_zone_alloc(kmem_zone_t *zone, xfs_km_flags_t flags)
> -{
> - int retries = 0;
> - gfp_t lflags = kmem_flags_convert(flags);
> - void *ptr;
> -
> - trace_kmem_zone_alloc(kmem_cache_size(zone), flags, _RET_IP_);
> - do {
> - ptr = kmem_cache_alloc(zone, lflags);
> - if (ptr || (flags & KM_MAYFAIL))
> - return ptr;
> - if (!(++retries % 100))
> - xfs_err(NULL,
> - "%s(%u) possible memory allocation deadlock in %s (mode:0x%x)",
> - current->comm, current->pid,
> - __func__, lflags);
> - congestion_wait(BLK_RW_ASYNC, HZ/50);
> - } while (1);
> -}
> diff --git a/fs/xfs/kmem.h b/fs/xfs/kmem.h
> index 3242de676808..7e4ad73771ce 100644
> --- a/fs/xfs/kmem.h
> +++ b/fs/xfs/kmem.h
> @@ -76,8 +76,6 @@ kmem_zalloc_large(size_t size, xfs_km_flags_t flags)
> #define kmem_zone kmem_cache
> #define kmem_zone_t struct kmem_cache
>
> -extern void *kmem_zone_alloc(kmem_zone_t *, xfs_km_flags_t);
> -
> static inline struct page *
> kmem_to_page(void *addr)
> {
> diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c
> index 675613c7bacb..42cae87bdd2d 100644
> --- a/fs/xfs/libxfs/xfs_alloc.c
> +++ b/fs/xfs/libxfs/xfs_alloc.c
> @@ -2351,7 +2351,8 @@ 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 9fbdca183465..37596e49b92e 100644
> --- a/fs/xfs/libxfs/xfs_bmap.c
> +++ b/fs/xfs/libxfs/xfs_bmap.c
> @@ -554,7 +554,8 @@ __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 950e8a51ec66..985f48e3795f 100644
> --- a/fs/xfs/xfs_icache.c
> +++ b/fs/xfs/xfs_icache.c
> @@ -40,7 +40,7 @@ xfs_inode_alloc(
> * KM_MAYFAIL and return NULL here on ENOMEM. Set the
> * code up to do this anyway.
> */
> - ip = kmem_zone_alloc(xfs_inode_zone, 0);
> + ip = kmem_cache_alloc(xfs_inode_zone, GFP_KERNEL | __GFP_NOFAIL);
> if (!ip)
> return NULL;
> if (inode_init_always(mp->m_super, VFS_I(ip))) {
> diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
> index c13bb3655e48..192f499ccd7e 100644
> --- a/fs/xfs/xfs_trace.h
> +++ b/fs/xfs/xfs_trace.h
> @@ -3571,7 +3571,6 @@ DEFINE_KMEM_EVENT(kmem_alloc);
> DEFINE_KMEM_EVENT(kmem_alloc_io);
> DEFINE_KMEM_EVENT(kmem_alloc_large);
> DEFINE_KMEM_EVENT(kmem_realloc);
> -DEFINE_KMEM_EVENT(kmem_zone_alloc);
>
> #endif /* _TRACE_XFS_H */
>
> --
> 2.23.0
>
