Re: [PATCH net-next 4/8] net/mlx4_en: Add __GFP_COLD gfp flags in alloc_pages
From: Eric Dumazet <hidden>
Date: 2014-10-30 17:16:07
On Thu, 2014-10-30 at 18:06 +0200, Or Gerlitz wrote:
quoted hunk ↗ jump to hunk
From: Ido Shamay <redacted> Needed in order to get cache cold pages (L3 flushed) for HW scatter. Otherwise memory may flush those entries when the packet comes from PCI, causing back pressure resulting in BW decrease. Signed-off-by: Ido Shamay <redacted> Signed-off-by: Amir Vadai <redacted> --- drivers/net/ethernet/mellanox/mlx4/en_rx.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-)diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c index 4cb716f..9d616a8 100644 --- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c +++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c@@ -54,7 +54,7 @@ static int mlx4_alloc_pages(struct mlx4_en_priv *priv, dma_addr_t dma; for (order = MLX4_EN_ALLOC_PREFER_ORDER; ;) { - gfp_t gfp = _gfp; + gfp_t gfp = _gfp | __GFP_COLD;
This should be set by callers, to avoid extra code GFP_ATOMIC | __GFP_COLD or GFP_KERNEL | __GFP_COLD
if (order) gfp |= __GFP_COMP | __GFP_NOWARN;