From: Ming Lei Date: Wed, 16 Mar 2022 01:27:08 +0000 (+0800) Subject: lib/sbitmap: allocate sb->map via kvzalloc_node X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=863a66cdb4df25fd146d9851c3289072298566d5;p=linux.git lib/sbitmap: allocate sb->map via kvzalloc_node sbitmap has been used in scsi for replacing atomic operations on sdev->device_busy, so IOPS on some fast scsi storage can be improved. However, sdev->device_busy can be changed in fast path, so we have to allocate the sb->map statically. sdev->device_busy has been capped to 1024, but some drivers may configure the default depth as < 8, then cause each sbitmap word to hold only one bit. Finally 1024 * 128( sizeof(sbitmap_word)) bytes is needed for sb->map, given it is order 5 allocation, sometimes it may fail. Avoid the issue by using kvzalloc_node() for allocating sb->map. Cc: Ewan D. Milne Signed-off-by: Ming Lei Reviewed-by: Chaitanya Kulkarni Link: https://lore.kernel.org/r/20220316012708.354668-1-ming.lei@redhat.com Signed-off-by: Jens Axboe --- diff --git a/include/linux/sbitmap.h b/include/linux/sbitmap.h index dffeb8281c2d9..8f5a86e210b90 100644 --- a/include/linux/sbitmap.h +++ b/include/linux/sbitmap.h @@ -174,7 +174,7 @@ static inline unsigned int __map_depth(const struct sbitmap *sb, int index) static inline void sbitmap_free(struct sbitmap *sb) { free_percpu(sb->alloc_hint); - kfree(sb->map); + kvfree(sb->map); sb->map = NULL; } diff --git a/lib/sbitmap.c b/lib/sbitmap.c index 2eb3de18ded3e..ae4fd4de9ebe7 100644 --- a/lib/sbitmap.c +++ b/lib/sbitmap.c @@ -110,7 +110,7 @@ int sbitmap_init_node(struct sbitmap *sb, unsigned int depth, int shift, sb->alloc_hint = NULL; } - sb->map = kcalloc_node(sb->map_nr, sizeof(*sb->map), flags, node); + sb->map = kvzalloc_node(sb->map_nr * sizeof(*sb->map), flags, node); if (!sb->map) { free_percpu(sb->alloc_hint); return -ENOMEM;