Re: [dpdk-dev] [PATCH] mem: fix allocation failure on non-NUMA kernel

["Burakov, Anatoly" <anatoly.burakov@intel.com>]

On 05-Aug-20 1:26 PM, Nick Connolly wrote:
> Running dpdk-helloworld on Linux with lib numa present,
> but no kernel support for NUMA (CONFIG_NUMA=n) causes
> ret_service_init() to fail with EAL: error allocating
> rte services array.
> 
> alloc_seg() calls get_mempolicy to verify that the allocation
> has happened on the correct socket, but receives ENOSYS from
> the kernel and fails the allocation.
> 
> The allocated socket should only be verified if check_numa() is true.
> 
> Fixes: 2a96c88be83e ("mem: ease init in a docker container")
> Cc: nicolas.dichtel@6wind.com
> Cc: stable@dpdk.org
> Signed-off-by: Nick Connolly <nick.connolly@mayadata.io>
> ---
>   lib/librte_eal/linux/eal_memalloc.c | 28 +++++++++++++++++-----------
>   1 file changed, 17 insertions(+), 11 deletions(-)
> 
> diff --git a/lib/librte_eal/linux/eal_memalloc.c b/lib/librte_eal/linux/eal_memalloc.c
> index db60e7997..179757809 100644
> --- a/lib/librte_eal/linux/eal_memalloc.c
> +++ b/lib/librte_eal/linux/eal_memalloc.c
> @@ -610,17 +610,23 @@ alloc_seg(struct rte_memseg *ms, void *addr, int socket_id,
>   	}
>   
>   #ifdef RTE_EAL_NUMA_AWARE_HUGEPAGES
> -	ret = get_mempolicy(&cur_socket_id, NULL, 0, addr,
> -			    MPOL_F_NODE | MPOL_F_ADDR);
> -	if (ret < 0) {
> -		RTE_LOG(DEBUG, EAL, "%s(): get_mempolicy: %s\n",
> -			__func__, strerror(errno));
> -		goto mapped;
> -	} else if (cur_socket_id != socket_id) {
> -		RTE_LOG(DEBUG, EAL,
> -				"%s(): allocation happened on wrong socket (wanted %d, got %d)\n",
> -			__func__, socket_id, cur_socket_id);
> -		goto mapped;
> +	if (check_numa()) {
> +		ret = get_mempolicy(&cur_socket_id, NULL, 0, addr,
> +					MPOL_F_NODE | MPOL_F_ADDR);
> +		if (ret < 0) {
> +			RTE_LOG(DEBUG, EAL, "%s(): get_mempolicy: %s\n",
> +				__func__, strerror(errno));
> +			goto mapped;
> +		} else if (cur_socket_id != socket_id) {
> +			RTE_LOG(DEBUG, EAL,
> +					"%s(): allocation happened on wrong socket (wanted %d, got %d)\n",
> +				__func__, socket_id, cur_socket_id);
> +			goto mapped;
> +		}
> +	} else {
> +		if (rte_socket_count() > 1)
> +			RTE_LOG(DEBUG, EAL, "%s(): not checking socket for allocation (wanted %d)\n",
> +					__func__, socket_id);
>   	}

If there is no kernel support for NUMA, how would we end up with >1 
socket count?

>   #else
>   	if (rte_socket_count() > 1)
> 


-- 
Thanks,
Anatoly