Hi
I think that GFP_NOWAIT already includes __GFP_NORETRY too. So, should we
drop __GFP_NORETRY as well?
Mikulas
On Mon, 11 Aug 2025, Qianfeng Rong wrote:
> GFP_NOWAIT already includes __GFP_NOWARN, so let's remove the redundant
> __GFP_NOWARN. Also update comments to clarify the flag semantics.
>
> Signed-off-by: Qianfeng Rong <rongqianf...@vivo.com>
> ---
> drivers/md/dm-bufio.c | 10 +++++-----
> 1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c
> index ff7595caf440..4b20854e92f5 100644
> --- a/drivers/md/dm-bufio.c
> +++ b/drivers/md/dm-bufio.c
> @@ -1337,7 +1337,7 @@ static void use_bio(struct dm_buffer *b, enum req_op
> op, sector_t sector,
> char *ptr;
> unsigned int len;
>
> - bio = bio_kmalloc(1, GFP_NOWAIT | __GFP_NORETRY | __GFP_NOWARN);
> + bio = bio_kmalloc(1, GFP_NOWAIT | __GFP_NORETRY);
> if (!bio) {
> use_dmio(b, op, sector, n_sectors, offset, ioprio);
> return;
> @@ -1601,18 +1601,18 @@ static struct dm_buffer
> *__alloc_buffer_wait_no_callback(struct dm_bufio_client
> * dm-bufio is resistant to allocation failures (it just keeps
> * one buffer reserved in cases all the allocations fail).
> * So set flags to not try too hard:
> - * GFP_NOWAIT: don't wait; if we need to sleep we'll release our
> - * mutex and wait ourselves.
> + * GFP_NOWAIT: don't wait and don't print a warning in case of
> + * failure; if we need to sleep we'll release our mutex
> + * and wait ourselves.
> * __GFP_NORETRY: don't retry and rather return failure
> * __GFP_NOMEMALLOC: don't use emergency reserves
> - * __GFP_NOWARN: don't print a warning in case of failure
> *
> * For debugging, if we set the cache size to 1, no new buffers will
> * be allocated.
> */
> while (1) {
> if (dm_bufio_cache_size_latch != 1) {
> - b = alloc_buffer(c, GFP_NOWAIT | __GFP_NORETRY |
> __GFP_NOMEMALLOC | __GFP_NOWARN);
> + b = alloc_buffer(c, GFP_NOWAIT | __GFP_NORETRY |
> __GFP_NOMEMALLOC);
> if (b)
> return b;
> }
> --
> 2.34.1
>
