Re: [PATCH v3] IB/mlx5: Reduce max order of memory allocated for xlt update

From: Leon Romanovsky
Date: Sun Apr 04 2021 - 06:38:13 EST


On Sat, Apr 03, 2021 at 04:53:55AM +0000, Praveen Kumar Kannoju wrote:
> 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. This patch adds this flag
> to the mask.
>
> Signed-off-by: Praveen Kumar Kannoju <praveen.kannoju@xxxxxxxxxx>
> ---
> drivers/infiniband/hw/mlx5/mr.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>

Thanks a lot,
Acked-by: Leon Romanovsky <leonro@xxxxxxxxxx>