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 <emilne@xxxxxxxxxx>
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
---
include/linux/sbitmap.h | 2 +-
lib/sbitmap.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/include/linux/sbitmap.h b/include/linux/sbitmap.h
index dffeb8281c2d..8f5a86e210b9 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 2eb3de18ded3..ae4fd4de9ebe 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;
--
2.31.1
