| Message ID | 1412941698-17502-5-git-send-email-edumazet@google.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c index a33048ee9621..01660c595f5c 100644 --- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c +++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c @@ -76,10 +76,10 @@ static int mlx4_alloc_pages(struct mlx4_en_priv *priv, page_alloc->dma = dma; page_alloc->page_offset = frag_info->frag_align; /* Not doing get_page() for each frag is a big win - * on asymetric workloads. + * on asymetric workloads. Note we can not use atomic_set(). */ - atomic_set(&page->_count, - page_alloc->page_size / frag_info->frag_stride); + atomic_add(page_alloc->page_size / frag_info->frag_stride - 1, + &page->_count); return 0; }
This is illegal to use atomic_set(&page->_count, ...) even if we 'own' the page. Other entities in the kernel need to use get_page_unless_zero() to get a reference to the page before testing page properties, so we could loose a refcount increment. Signed-off-by: Eric Dumazet <edumazet@google.com> --- drivers/net/ethernet/mellanox/mlx4/en_rx.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)