| Message ID | 20230331124959.40468-1-nbd@nbd.name (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | e669ce46740a9815953bb4452a6bc5a7fdc21a50 |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net] net: ethernet: mtk_eth_soc: fix remaining throughput regression | expand |
Hello: This patch was applied to netdev/net.git (main) by David S. Miller <davem@davemloft.net>: On Fri, 31 Mar 2023 14:49:59 +0200 you wrote: > Based on further tests, it seems that the QDMA shaper is not able to > perform shaping close to the MAC link rate without throughput loss. > This cannot be compensated by increasing the shaping rate, so it seems > to be an internal limit. > > Fix the remaining throughput regression by detecting that condition and > limiting shaping to ports with lower link speed. > > [...] Here is the summary with links: - [net] net: ethernet: mtk_eth_soc: fix remaining throughput regression https://git.kernel.org/netdev/net/c/e669ce46740a You are awesome, thank you!
diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c index 282f9435d5ff..e14050e17862 100644 --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c @@ -753,6 +753,7 @@ static void mtk_mac_link_up(struct phylink_config *config, MAC_MCR_FORCE_RX_FC); /* Configure speed */ + mac->speed = speed; switch (speed) { case SPEED_2500: case SPEED_1000: @@ -3235,6 +3236,9 @@ static int mtk_device_event(struct notifier_block *n, unsigned long event, void if (dp->index >= MTK_QDMA_NUM_QUEUES) return NOTIFY_DONE; + if (mac->speed > 0 && mac->speed <= s.base.speed) + s.base.speed = 0; + mtk_set_queue_speed(eth, dp->index + 3, s.base.speed); return NOTIFY_DONE;
Based on further tests, it seems that the QDMA shaper is not able to perform shaping close to the MAC link rate without throughput loss. This cannot be compensated by increasing the shaping rate, so it seems to be an internal limit. Fix the remaining throughput regression by detecting that condition and limiting shaping to ports with lower link speed. This patch intentionally ignores link speed gain from TRGMII, because even on such links, shaping to 1000 Mbit/s incurs some throughput degradation. Fixes: f63959c7eec3 ("net: ethernet: mtk_eth_soc: implement multi-queue support for per-port queues") Tested-By: Frank Wunderlich <frank-w@public-files.de> Reported-by: Frank Wunderlich <frank-w@public-files.de> Signed-off-by: Felix Fietkau <nbd@nbd.name> --- drivers/net/ethernet/mediatek/mtk_eth_soc.c | 4 ++++ 1 file changed, 4 insertions(+)