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)', as '__packed'
alone means byte aligned, and can cause compiler to generate horrible
code on architectures that 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>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
unsigned int bi_bvec_done; /* number of bytes completed in
current bvec */
unsigned int bi_bvec_done; /* number of bytes completed in
current bvec */
+} __packed __aligned(4);
struct bvec_iter_all {
struct bio_vec bv;
struct bvec_iter_all {
struct bio_vec bv;