Re: [PATCH V3,net-next] net: mana: Add page pool for RX buffers
From: Jesper Dangaard Brouer <hidden>
Date: 2023-07-24 11:30:32
Also in:
bpf, linux-hyperv, linux-rdma, lkml
On 21/07/2023 21.05, Haiyang Zhang wrote:
quoted hunk ↗ jump to hunk
Add page pool for RX buffers for faster buffer cycle and reduce CPU usage. The standard page pool API is used. Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com> --- V3: Update xdp mem model, pool param, alloc as suggested by Jakub Kicinski V2: Use the standard page pool API as suggested by Jesper Dangaard Brouer --- drivers/net/ethernet/microsoft/mana/mana_en.c | 91 +++++++++++++++---- include/net/mana/mana.h | 3 + 2 files changed, 78 insertions(+), 16 deletions(-)diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c index a499e460594b..4307f25f8c7a 100644 --- a/drivers/net/ethernet/microsoft/mana/mana_en.c +++ b/drivers/net/ethernet/microsoft/mana/mana_en.c
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quoted hunk ↗ jump to hunk
@@ -1659,6 +1679,8 @@ static void mana_poll_rx_cq(struct mana_cq *cq) if (rxq->xdp_flush) xdp_do_flush(); + + page_pool_nid_changed(rxq->page_pool, numa_mem_id());
I don't think this page_pool_nid_changed() called is needed, if you do as I suggest below (nid = NUMA_NO_NODE).
} static int mana_cq_handler(void *context, struct gdma_queue *gdma_queue)
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quoted hunk ↗ jump to hunk
@@ -2008,6 +2041,25 @@ static int mana_push_wqe(struct mana_rxq *rxq) return 0; } +static int mana_create_page_pool(struct mana_rxq *rxq) +{ + struct page_pool_params pprm = {};
You are implicitly assigning NUMA node id zero.
+ int ret; + + pprm.pool_size = RX_BUFFERS_PER_QUEUE; + pprm.napi = &rxq->rx_cq.napi;
You likely want to assign pprm.nid to NUMA_NO_NODE pprm.nid = NUMA_NO_NODE; For most drivers it is recommended to assign ``NUMA_NO_NODE`` (value -1) as the NUMA ID to ``pp_params.nid``. When ``CONFIG_NUMA`` is enabled this setting will automatically select the (preferred) NUMA node (via ``numa_mem_id()``) based on where NAPI RX-processing is currently running. The effect is that page_pool will only use recycled memory when NUMA node match running CPU. This assumes CPU refilling driver RX-ring will also run RX-NAPI. If a driver want more control over the NUMA node memory selection, drivers can assign (``pp_params.nid``) something else than `NUMA_NO_NODE`` and runtime adjust via function ``page_pool_nid_changed()``. I will update [1] with this info. - Docs [1] https://kernel.org/doc/html/latest/networking/page_pool.html#registration
+
+ rxq->page_pool = page_pool_create(&pprm);
+
+ if (IS_ERR(rxq->page_pool)) {
+ ret = PTR_ERR(rxq->page_pool);
+ rxq->page_pool = NULL;
+ return ret;
+ }
+
+ return 0;
+}
+