[net PATCH v2 1/1] drivers: net: cpsw: fix disabling of tx interrupt in rx isr

[net PATCH v2 1/1] drivers: net: cpsw: fix disabling of tx interrupt in rx isr

[Mugunthan V N]

In commit 'c03abd84634d ("net: ethernet: cpsw: don't requests
IRQs we don't use")', common isr is split into tx and rx, but
in rx isr tx interrupt is also disabledi in cpsw_disable_irq().
So tx interrupts are not handled during rx interrupts and rx
napi completion and results in poor tx performance by 40Mbps.
Fixing by disabling only rx interrupt in rx isr.

Cc: Felipe Balbi <balbi@ti.com>
Cc: <stable@vger.kernel.org> # v4.0+
Signed-off-by: Mugunthan V N <mugunthanvnm@ti.com>
---

Changes from initial version:
* Modified only the commit message as commented by Balbi it is
  not a regression and the patch improves tx performance

---

 drivers/net/ethernet/ti/cpsw.c | 19 +++----------------
 1 file changed, 3 insertions(+), 16 deletions(-)

diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
index e778703..f335bf1 100644
--- a/drivers/net/ethernet/ti/cpsw.c
+++ b/drivers/net/ethernet/ti/cpsw.c
@@ -138,19 +138,6 @@ do {								\
 #define CPSW_CMINTMAX_INTVL	(1000 / CPSW_CMINTMIN_CNT)
 #define CPSW_CMINTMIN_INTVL	((1000 / CPSW_CMINTMAX_CNT) + 1)
 
-#define cpsw_enable_irq(priv)	\
-	do {			\
-		u32 i;		\
-		for (i = 0; i < priv->num_irqs; i++) \
-			enable_irq(priv->irqs_table[i]); \
-	} while (0)
-#define cpsw_disable_irq(priv)	\
-	do {			\
-		u32 i;		\
-		for (i = 0; i < priv->num_irqs; i++) \
-			disable_irq_nosync(priv->irqs_table[i]); \
-	} while (0)
-
 #define cpsw_slave_index(priv)				\
 		((priv->data.dual_emac) ? priv->emac_port :	\
 		priv->data.active_slave)
@@ -783,7 +770,7 @@ static irqreturn_t cpsw_rx_interrupt(int irq, void *dev_id)
 
 	cpsw_intr_disable(priv);
 	if (priv->irq_enabled == true) {
-		cpsw_disable_irq(priv);
+		disable_irq_nosync(priv->irqs_table[0]);
 		priv->irq_enabled = false;
 	}
 
@@ -819,7 +806,7 @@ static int cpsw_poll(struct napi_struct *napi, int budget)
 		prim_cpsw = cpsw_get_slave_priv(priv, 0);
 		if (prim_cpsw->irq_enabled == false) {
 			prim_cpsw->irq_enabled = true;
-			cpsw_enable_irq(priv);
+			enable_irq(priv->irqs_table[0]);
 		}
 	}
 
@@ -1335,7 +1322,7 @@ static int cpsw_ndo_open(struct net_device *ndev)
 	if (prim_cpsw->irq_enabled == false) {
 		if ((priv == prim_cpsw) || !netif_running(prim_cpsw->ndev)) {
 			prim_cpsw->irq_enabled = true;
-			cpsw_enable_irq(prim_cpsw);
+			enable_irq(prim_cpsw->irqs_table[0]);
 		}
 	}
 
-- 
2.5.0.rc0

Re: [net PATCH v2 1/1] drivers: net: cpsw: fix disabling of tx interrupt in rx isr

[David Miller]

From: Mugunthan V N <mugunthanvnm@ti.com>
Date: Wed, 8 Jul 2015 14:35:22 +0530

> In commit 'c03abd84634d ("net: ethernet: cpsw: don't requests
> IRQs we don't use")', common isr is split into tx and rx, but
> in rx isr tx interrupt is also disabledi in cpsw_disable_irq().
> So tx interrupts are not handled during rx interrupts and rx
> napi completion and results in poor tx performance by 40Mbps.
> Fixing by disabling only rx interrupt in rx isr.
> 
> Cc: Felipe Balbi <balbi@ti.com>
> Cc: <stable@vger.kernel.org> # v4.0+
> Signed-off-by: Mugunthan V N <mugunthanvnm@ti.com>

Applied, thanks.