diff options
| -rw-r--r-- | drivers/net/ethernet/intel/fm10k/fm10k_main.c | 7 | ||||
| -rw-r--r-- | drivers/net/ethernet/intel/igb/igb_main.c | 7 | ||||
| -rw-r--r-- | drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 8 | ||||
| -rw-r--r-- | drivers/net/ethernet/mellanox/mlx4/en_rx.c | 6 | ||||
| -rw-r--r-- | net/core/skbuff.c | 25 |
5 files changed, 30 insertions, 23 deletions
diff --git a/drivers/net/ethernet/intel/fm10k/fm10k_main.c b/drivers/net/ethernet/intel/fm10k/fm10k_main.c index 6c800a330d6..9d7118a0d67 100644 --- a/drivers/net/ethernet/intel/fm10k/fm10k_main.c +++ b/drivers/net/ethernet/intel/fm10k/fm10k_main.c @@ -219,11 +219,10 @@ static bool fm10k_can_reuse_rx_page(struct fm10k_rx_buffer *rx_buffer, /* flip page offset to other buffer */ rx_buffer->page_offset ^= FM10K_RX_BUFSZ; - /* since we are the only owner of the page and we need to - * increment it, just set the value to 2 in order to avoid - * an unnecessary locked operation + /* Even if we own the page, we are not allowed to use atomic_set() + * This would break get_page_unless_zero() users. */ - atomic_set(&page->_count, 2); + atomic_inc(&page->_count); #else /* move offset up to the next cache line */ rx_buffer->page_offset += truesize; diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c index ae59c0b108c..a21b14495eb 100644 --- a/drivers/net/ethernet/intel/igb/igb_main.c +++ b/drivers/net/ethernet/intel/igb/igb_main.c @@ -6545,11 +6545,10 @@ static bool igb_can_reuse_rx_page(struct igb_rx_buffer *rx_buffer, /* flip page offset to other buffer */ rx_buffer->page_offset ^= IGB_RX_BUFSZ; - /* since we are the only owner of the page and we need to - * increment it, just set the value to 2 in order to avoid - * an unnecessary locked operation + /* Even if we own the page, we are not allowed to use atomic_set() + * This would break get_page_unless_zero() users. */ - atomic_set(&page->_count, 2); + atomic_inc(&page->_count); #else /* move offset up to the next cache line */ rx_buffer->page_offset += truesize; diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c index d677b5a23b5..fec5212d433 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c @@ -1865,12 +1865,10 @@ static bool ixgbe_add_rx_frag(struct ixgbe_ring *rx_ring, /* flip page offset to other buffer */ rx_buffer->page_offset ^= truesize; - /* - * since we are the only owner of the page and we need to - * increment it, just set the value to 2 in order to avoid - * an unecessary locked operation + /* Even if we own the page, we are not allowed to use atomic_set() + * This would break get_page_unless_zero() users. */ - atomic_set(&page->_count, 2); + atomic_inc(&page->_count); #else /* move offset up to the next cache line */ rx_buffer->page_offset += truesize; diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c index a33048ee962..01660c595f5 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; } diff --git a/net/core/skbuff.c b/net/core/skbuff.c index a30d750647e..829d013745a 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -360,18 +360,29 @@ refill: goto end; } nc->frag.size = PAGE_SIZE << order; -recycle: - atomic_set(&nc->frag.page->_count, NETDEV_PAGECNT_MAX_BIAS); + /* Even if we own the page, we do not use atomic_set(). + * This would break get_page_unless_zero() users. + */ + atomic_add(NETDEV_PAGECNT_MAX_BIAS - 1, + &nc->frag.page->_count); nc->pagecnt_bias = NETDEV_PAGECNT_MAX_BIAS; nc->frag.offset = 0; } if (nc->frag.offset + fragsz > nc->frag.size) { - /* avoid unnecessary locked operations if possible */ - if ((atomic_read(&nc->frag.page->_count) == nc->pagecnt_bias) || - atomic_sub_and_test(nc->pagecnt_bias, &nc->frag.page->_count)) - goto recycle; - goto refill; + if (atomic_read(&nc->frag.page->_count) != nc->pagecnt_bias) { + if (!atomic_sub_and_test(nc->pagecnt_bias, + &nc->frag.page->_count)) + goto refill; + /* OK, page count is 0, we can safely set it */ + atomic_set(&nc->frag.page->_count, + NETDEV_PAGECNT_MAX_BIAS); + } else { + atomic_add(NETDEV_PAGECNT_MAX_BIAS - nc->pagecnt_bias, + &nc->frag.page->_count); + } + nc->pagecnt_bias = NETDEV_PAGECNT_MAX_BIAS; + nc->frag.offset = 0; } data = page_address(nc->frag.page) + nc->frag.offset; |