From 7e111bbff92620f56609a81353bba5bd1944851b Mon Sep 17 00:00:00 2001 From: Praveen Kumar Kannoju <praveen.kannoju@oracle.com> Date: Sat, 3 Apr 2021 04:53:55 +0000 Subject: IB/mlx5: Reduce max order of memory allocated for xlt update To update xlt (during mlx5_ib_reg_user_mr()), the driver can request up to 1 MB (order-8) memory, depending on the size of the MR. This costly allocation can sometimes take very long to return (a few seconds). This causes the calling application to hang for a long time, especially when the system is fragmented. To avoid these long latency spikes, the calls the higher order allocations need to fail faster in case they are not available. In order to acheive this we need __GFP_NORETRY flag in the gfp_mask before during fetching the free pages. Allow the algorithm to automatically fall back to smaller page sizes. Link: https://lore.kernel.org/r/1617425635-35631-1-git-send-email-praveen.kannoju@oracle.com Signed-off-by: Praveen Kumar Kannoju <praveen.kannoju@oracle.com> Acked-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> --- drivers/infiniband/hw/mlx5/mr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/infiniband/hw/mlx5') diff --git a/drivers/infiniband/hw/mlx5/mr.c b/drivers/infiniband/hw/mlx5/mr.c index eeb9f7e15634..ab5bffb919d1 100644 --- a/drivers/infiniband/hw/mlx5/mr.c +++ b/drivers/infiniband/hw/mlx5/mr.c @@ -1004,7 +1004,7 @@ static void *mlx5_ib_alloc_xlt(size_t *nents, size_t ent_size, gfp_t gfp_mask) */ might_sleep(); - gfp_mask |= __GFP_ZERO; + gfp_mask |= __GFP_ZERO | __GFP_NORETRY; /* * If the system already has a suitable high order page then just use -- cgit v1.2.3