From 664b60f6babc98ee03c2ff15b9482cc8c5e15a83 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 6 Apr 2016 09:47:01 +1000 Subject: xfs: improve kmem_realloc Use krealloc to implement our realloc function. This helps to avoid new allocations if we are still in the slab bucket. At least for the bmap btree root that's actually the common case. This also allows removing the now unused oldsize argument. Signed-off-by: Christoph Hellwig Reviewed-by: Brian Foster Signed-off-by: Dave Chinner --- fs/xfs/kmem.c | 26 +++++++++++++++----------- 1 file changed, 15 insertions(+), 11 deletions(-) (limited to 'fs/xfs/kmem.c') diff --git a/fs/xfs/kmem.c b/fs/xfs/kmem.c index 686ba6fb20dd..339c696bbc01 100644 --- a/fs/xfs/kmem.c +++ b/fs/xfs/kmem.c @@ -93,19 +93,23 @@ kmem_zalloc_large(size_t size, xfs_km_flags_t flags) } void * -kmem_realloc(const void *ptr, size_t newsize, size_t oldsize, - xfs_km_flags_t flags) +kmem_realloc(const void *old, size_t newsize, xfs_km_flags_t flags) { - void *new; + int retries = 0; + gfp_t lflags = kmem_flags_convert(flags); + void *ptr; - new = kmem_alloc(newsize, flags); - if (ptr) { - if (new) - memcpy(new, ptr, - ((oldsize < newsize) ? oldsize : newsize)); - kmem_free(ptr); - } - return new; + do { + ptr = krealloc(old, newsize, lflags); + if (ptr || (flags & (KM_MAYFAIL|KM_NOSLEEP))) + return ptr; + if (!(++retries % 100)) + xfs_err(NULL, + "%s(%u) possible memory allocation deadlock size %zu in %s (mode:0x%x)", + current->comm, current->pid, + newsize, __func__, lflags); + congestion_wait(BLK_RW_ASYNC, HZ/50); + } while (1); } void * -- cgit v1.2.3