Hi Saeed On 2/21/2018 12:13 PM, Saeed Mahameed wrote:
From: Yonatan Cohen <yonatanc@xxxxxxxxxxxx> The current implementation of create CQ requires contiguous memory, such requirement is problematic once the memory is fragmented or the system is low in memory, it causes for failures in dma_zalloc_coherent(). This patch implements new scheme of fragmented CQ to overcome this issue by introducing new type: 'struct mlx5_frag_buf_ctrl' to allocate fragmented buffers, rather than contiguous ones. Base the Completion Queues (CQs) on this new fragmented buffer. It fixes following crashes: kworker/29:0: page allocation failure: order:6, mode:0x80d0 CPU: 29 PID: 8374 Comm: kworker/29:0 Tainted: G OE 3.10.0 Workqueue: ib_cm cm_work_handler [ib_cm] Call Trace: [<>] dump_stack+0x19/0x1b [<>] warn_alloc_failed+0x110/0x180 [<>] __alloc_pages_slowpath+0x6b7/0x725 [<>] __alloc_pages_nodemask+0x405/0x420 [<>] dma_generic_alloc_coherent+0x8f/0x140 [<>] x86_swiotlb_alloc_coherent+0x21/0x50 [<>] mlx5_dma_zalloc_coherent_node+0xad/0x110 [mlx5_core] [<>] ? mlx5_db_alloc_node+0x69/0x1b0 [mlx5_core] [<>] mlx5_buf_alloc_node+0x3e/0xa0 [mlx5_core] [<>] mlx5_buf_alloc+0x14/0x20 [mlx5_core] [<>] create_cq_kernel+0x90/0x1f0 [mlx5_ib] [<>] mlx5_ib_create_cq+0x3b0/0x4e0 [mlx5_ib] Signed-off-by: Yonatan Cohen <yonatanc@xxxxxxxxxxxx> Reviewed-by: Tariq Toukan <tariqt@xxxxxxxxxxxx> Signed-off-by: Leon Romanovsky <leon@xxxxxxxxxx> Signed-off-by: Saeed Mahameed <saeedm@xxxxxxxxxxxx> ---
Jason mentioned about this patch to me off-list. We were seeing similar issue with SRQs & QPs. So wondering whether you have any plans to do similar change for other resouces too so that they don't rely on higher order page allocation for icm tables. Regards, Santosh -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
