Re: [PATCH v3 net] octeontx2-pf: fix page_pool creation fail for rings > 32k

[Jesper Dangaard Brouer]

On 24/08/2023 05.03, Ratheesh Kannoth wrote:
> octeontx2 driver calls page_pool_create() during driver probe()
> and fails if queue size > 32k. Page pool infra uses these buffers
> as shock absorbers for burst traffic. These pages are pinned down
> over time as working sets varies, due to the recycling nature
> of page pool, given page pool (currently) don't have a shrinker
> mechanism, the pages remain pinned down in ptr_ring.
> Instead of clamping page_pool size to 32k at
> most, limit it even more to 2k to avoid wasting memory.
>
> This have been tested on octeontx2 CN10KA hardware.
> TCP and UDP tests using iperf shows no performance regressions.
>
> Fixes: b2e3406a38f0 ("octeontx2-pf: Add support for page pool")
> Suggested-by: Alexander Lobakin <aleksander.lobakin@xxxxxxxxx>
> Reviewed-by: Sunil Goutham <sgoutham@xxxxxxxxxxx>
> Signed-off-by: Ratheesh Kannoth <rkannoth@xxxxxxxxxxx>
> ---

Again

Acked-by: Jesper Dangaard Brouer <hawk@xxxxxxxxxx>


> ChangeLogs:
>
> v2->v3: Fix macro aligment and header file changes suggested by
> 	Alexander Lobakin
> v1->v2: Commit message changes and typo fixes
> v0->v1: Commit message changes.
> ---
>   drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c | 2 +-
>   drivers/net/ethernet/marvell/octeontx2/nic/otx2_txrx.h   | 2 ++
>   2 files changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c
> index 77c8f650f7ac..3e1c70c74622 100644
> --- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c
> +++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c
> @@ -1432,7 +1432,7 @@ int otx2_pool_init(struct otx2_nic *pfvf, u16 pool_id,
>   	}
>   
>   	pp_params.flags = PP_FLAG_PAGE_FRAG | PP_FLAG_DMA_MAP;
> -	pp_params.pool_size = numptrs;
> +	pp_params.pool_size = min(OTX2_PAGE_POOL_SZ, numptrs);
>   	pp_params.nid = NUMA_NO_NODE;
>   	pp_params.dev = pfvf->dev;
>   	pp_params.dma_dir = DMA_FROM_DEVICE;
> diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_txrx.h b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_txrx.h
> index b5d689eeff80..9e3bfbe5c480 100644
> --- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_txrx.h
> +++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_txrx.h
> @@ -23,6 +23,8 @@
>   #define	OTX2_ETH_HLEN		(VLAN_ETH_HLEN + VLAN_HLEN)
>   #define	OTX2_MIN_MTU		60
>   
> +#define OTX2_PAGE_POOL_SZ	2048
> +
>   #define OTX2_MAX_GSO_SEGS	255
>   #define OTX2_MAX_FRAGS_IN_SQE	9
>