[PATCH net-next v1] net: stmmac: Set dma_sync_size to zero for discarded frames

[PATCH net-next v1] net: stmmac: Set dma_sync_size to zero for discarded frames

[Furong Xu]

If a frame is going to be discarded by driver, this frame is never touched
by driver and the cache lines never become dirty obviously,
page_pool_recycle_direct() wastes CPU cycles on unnecessary calling of
page_pool_dma_sync_for_device() to sync entire frame.
page_pool_put_page() with sync_size setting to 0 is the proper method.

Signed-off-by: Furong Xu <0x1207@gmail.com>
---
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 6bc10ffe7a2b..1cdbf66574b3 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -5472,7 +5472,7 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue)
 		if (priv->extend_desc)
 			stmmac_rx_extended_status(priv, &priv->xstats, rx_q->dma_erx + entry);
 		if (unlikely(status == discard_frame)) {
-			page_pool_recycle_direct(rx_q->page_pool, buf->page);
+			page_pool_put_page(rx_q->page_pool, buf->page, 0, true);
 			buf->page = NULL;
 			error = 1;
 			if (!priv->hwts_rx_en)
-- 
2.34.1

Re: [PATCH net-next v1] net: stmmac: Set dma_sync_size to zero for discarded frames

[patchwork-bot+netdevbpf]

Hello:

This patch was applied to netdev/net-next.git (main)
by Paolo Abeni <pabeni@redhat.com>:

On Fri,  3 Jan 2025 17:37:33 +0800 you wrote:
> If a frame is going to be discarded by driver, this frame is never touched
> by driver and the cache lines never become dirty obviously,
> page_pool_recycle_direct() wastes CPU cycles on unnecessary calling of
> page_pool_dma_sync_for_device() to sync entire frame.
> page_pool_put_page() with sync_size setting to 0 is the proper method.
> 
> Signed-off-by: Furong Xu <0x1207@gmail.com>
> 
> [...]

Here is the summary with links:
  - [net-next,v1] net: stmmac: Set dma_sync_size to zero for discarded frames
    https://git.kernel.org/netdev/net-next/c/51cfbed198ca

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html