In commit 19416123ab3e ("block: define 'struct bvec_iter' as packed"),
what we need is to save the 4byte padding, and avoid `bio` to spread on
one extra cache line.
It is enough to define it as __packed __aligned(4), especially
__packed means byte aligned, and can cause compiler to generate
too horrible code on ARCHs which don't support unaligned access
in case that bvec_iter is embedded in other structures.
Cc: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Suggested-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Fixes: 19416123ab3e ("block: define 'struct bvec_iter' as packed")
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
---
include/linux/bvec.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/linux/bvec.h b/include/linux/bvec.h
index 555aae5448ae..bd1e361b351c 100644
--- a/include/linux/bvec.h
+++ b/include/linux/bvec.h
@@ -83,7 +83,7 @@ struct bvec_iter {
unsigned int bi_bvec_done; /* number of bytes completed in
current bvec */
-} __packed;
+} __packed __aligned(4);
struct bvec_iter_all {
struct bio_vec bv;
--
2.41.0
