From 117980c4c994b6fe58e873fe803c9bcdcb4337a3 Mon Sep 17 00:00:00 2001 From: Thadeu Lima de Souza Cascardo Date: Wed, 4 Apr 2012 09:40:40 +0000 Subject: [PATCH] mlx4: allocate just enough pages instead of always 4 pages The driver uses a 2-order allocation, which is too much on architectures like ppc64, which has a 64KiB page. This particular allocation is used for large packet fragments that may have a size of 512, 1024, 4096 or fill the whole allocation. So, a minimum size of 16384 is good enough and will be the same size that is used in architectures of 4KiB sized pages. This will avoid allocation failures that we see when the system is under stress, but still has plenty of memory, like the one below. This will also allow us to set the interface MTU to higher values like 9000, which was not possible on ppc64 without this patch. Node 1 DMA: 737*64kB 37*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB 0*8192kB 0*16384kB = 51904kB 83137 total pagecache pages 0 pages in swap cache Swap cache stats: add 0, delete 0, find 0/0 Free swap = 10420096kB Total swap = 10420096kB 107776 pages RAM 1184 pages reserved 147343 pages shared 28152 pages non-shared netstat: page allocation failure. order:2, mode:0x4020 Call Trace: [c0000001a4fa3770] [c000000000012f04] .show_stack+0x74/0x1c0 (unreliable) [c0000001a4fa3820] [c00000000016af38] .__alloc_pages_nodemask+0x618/0x930 [c0000001a4fa39a0] [c0000000001a71a0] .alloc_pages_current+0xb0/0x170 [c0000001a4fa3a40] [d00000000dcc3e00] .mlx4_en_alloc_frag+0x200/0x240 [mlx4_en] [c0000001a4fa3b10] [d00000000dcc3f8c] .mlx4_en_complete_rx_desc+0x14c/0x250 [mlx4_en] [c0000001a4fa3be0] [d00000000dcc4eec] .mlx4_en_process_rx_cq+0x62c/0x850 [mlx4_en] [c0000001a4fa3d20] [d00000000dcc5150] .mlx4_en_poll_rx_cq+0x40/0x90 [mlx4_en] [c0000001a4fa3dc0] [c0000000004e2bb8] .net_rx_action+0x178/0x450 [c0000001a4fa3eb0] [c00000000009c9b8] .__do_softirq+0x118/0x290 [c0000001a4fa3f90] [c000000000031df8] .call_do_softirq+0x14/0x24 [c000000184c3b520] [c00000000000e700] .do_softirq+0xf0/0x110 [c000000184c3b5c0] [c00000000009c6d4] .irq_exit+0xb4/0xc0 [c000000184c3b640] [c00000000000e964] .do_IRQ+0x144/0x230 Signed-off-by: Thadeu Lima de Souza Cascardo Signed-off-by: Kleber Sacilotto de Souza Tested-by: Kleber Sacilotto de Souza Signed-off-by: David S. Miller --- drivers/net/ethernet/mellanox/mlx4/mlx4_en.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h index 9e2b911a1230..d69fee41f24a 100644 --- a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h +++ b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h @@ -83,8 +83,9 @@ #define MLX4_EN_WATCHDOG_TIMEOUT (15 * HZ) -#define MLX4_EN_ALLOC_ORDER 2 -#define MLX4_EN_ALLOC_SIZE (PAGE_SIZE << MLX4_EN_ALLOC_ORDER) +/* Use the maximum between 16384 and a single page */ +#define MLX4_EN_ALLOC_SIZE PAGE_ALIGN(16384) +#define MLX4_EN_ALLOC_ORDER get_order(MLX4_EN_ALLOC_SIZE) #define MLX4_EN_MAX_LRO_DESCRIPTORS 32 -- 2.30.2