On 21/07/2023 21.05, Haiyang Zhang wrote:
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@xxxxxxxxxxxxx>
---
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
[...]
@@ -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)
[...]
@@ -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;
+}
+
