openwrt/target/linux/generic/backport-6.1/771-v6.7-02-net-stmmac-move-TX-timer-arm-after-DMA-enable.patch
Christian Marangi 797d46c34d
generic: 6.1: move stmmac backport fix patches to generic
Move stmmac backport fix patches from ipq806x to generic backport
directory as they got merged upstream and they fix wide performance
regression.

This will eventually cause performance increase on any user of the
stmmac driver.

Generic patch automatically refreshed with make target/linux/refresh.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
2024-01-21 22:17:25 +01:00

97 lines
3.5 KiB
Diff

From a594166387fe08e6f5a32130c400249a35b298f9 Mon Sep 17 00:00:00 2001
From: Christian Marangi <ansuelsmth@gmail.com>
Date: Wed, 18 Oct 2023 14:35:49 +0200
Subject: [PATCH 2/3] net: stmmac: move TX timer arm after DMA enable
Move TX timer arm call after DMA interrupt is enabled again.
The TX timer arm function changed logic and now is skipped if a napi is
already scheduled. By moving the TX timer arm call after DMA is enabled,
we permit to correctly skip if a DMA interrupt has been fired and a napi
has been scheduled again.
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
---
.../net/ethernet/stmicro/stmmac/stmmac_main.c | 22 +++++++++++++++----
1 file changed, 18 insertions(+), 4 deletions(-)
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -2528,9 +2528,13 @@ static void stmmac_bump_dma_threshold(st
* @priv: driver private structure
* @budget: napi budget limiting this functions packet handling
* @queue: TX queue index
+ * @pending_packets: signal to arm the TX coal timer
* Description: it reclaims the transmit resources after transmission completes.
+ * If some packets still needs to be handled, due to TX coalesce, set
+ * pending_packets to true to make NAPI arm the TX coal timer.
*/
-static int stmmac_tx_clean(struct stmmac_priv *priv, int budget, u32 queue)
+static int stmmac_tx_clean(struct stmmac_priv *priv, int budget, u32 queue,
+ bool *pending_packets)
{
struct stmmac_tx_queue *tx_q = &priv->dma_conf.tx_queue[queue];
unsigned int bytes_compl = 0, pkts_compl = 0;
@@ -2693,7 +2697,7 @@ static int stmmac_tx_clean(struct stmmac
/* We still have pending packets, let's call for a new scheduling */
if (tx_q->dirty_tx != tx_q->cur_tx)
- stmmac_tx_timer_arm(priv, queue);
+ *pending_packets = true;
__netif_tx_unlock_bh(netdev_get_tx_queue(priv->dev, queue));
@@ -5485,12 +5489,13 @@ static int stmmac_napi_poll_tx(struct na
struct stmmac_channel *ch =
container_of(napi, struct stmmac_channel, tx_napi);
struct stmmac_priv *priv = ch->priv_data;
+ bool pending_packets = false;
u32 chan = ch->index;
int work_done;
priv->xstats.napi_poll++;
- work_done = stmmac_tx_clean(priv, budget, chan);
+ work_done = stmmac_tx_clean(priv, budget, chan, &pending_packets);
work_done = min(work_done, budget);
if (work_done < budget && napi_complete_done(napi, work_done)) {
@@ -5501,6 +5506,10 @@ static int stmmac_napi_poll_tx(struct na
spin_unlock_irqrestore(&ch->lock, flags);
}
+ /* TX still have packet to handle, check if we need to arm tx timer */
+ if (pending_packets)
+ stmmac_tx_timer_arm(priv, chan);
+
return work_done;
}
@@ -5509,12 +5518,13 @@ static int stmmac_napi_poll_rxtx(struct
struct stmmac_channel *ch =
container_of(napi, struct stmmac_channel, rxtx_napi);
struct stmmac_priv *priv = ch->priv_data;
+ bool tx_pending_packets = false;
int rx_done, tx_done, rxtx_done;
u32 chan = ch->index;
priv->xstats.napi_poll++;
- tx_done = stmmac_tx_clean(priv, budget, chan);
+ tx_done = stmmac_tx_clean(priv, budget, chan, &tx_pending_packets);
tx_done = min(tx_done, budget);
rx_done = stmmac_rx_zc(priv, budget, chan);
@@ -5539,6 +5549,10 @@ static int stmmac_napi_poll_rxtx(struct
spin_unlock_irqrestore(&ch->lock, flags);
}
+ /* TX still have packet to handle, check if we need to arm tx timer */
+ if (tx_pending_packets)
+ stmmac_tx_timer_arm(priv, chan);
+
return min(rxtx_done, budget - 1);
}