| Message ID | 20240225030141.8364-1-ming.lei@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | block: define bvec_iter as __packed __aligned(4) | expand |
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;
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@redhat.com> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Fixes: 19416123ab3e ("block: define 'struct bvec_iter' as packed") Signed-off-by: Ming Lei <ming.lei@redhat.com> --- include/linux/bvec.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)