Re: [PATCH] sundance.c: high interrupt load [resent]
applied to netdev-2.6 so it can get some testing and review. Please send patches according to the format described at http://linux.yyz.us/patch-format.html Particularly, patches should apply with "patch -p1" and should include a signed-off-by line. Jeff - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] sundance.c: high interrupt load [resent]
applied to netdev-2.6 so it can get some testing and review. Please send patches according to the format described at http://linux.yyz.us/patch-format.html Particularly, patches should apply with patch -p1 and should include a signed-off-by line. Jeff - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[PATCH] sundance.c: high interrupt load [resent]
In at least some versions of Kernel 2.6 (2.6.8.1, 2.6.11-rc2)
the driver drivers/net/sundance.c creates high interrupt load
(~ 100 interrupts per second) even in case of no network traffic
at all.
It seems that some sort of TX overflow handling is misplaced
and triggers interrupts very often even in case of no data to
send. The TX overflow handling has been moved to a more
appropriate place.
While there, an off by one error of reading the TX status has
also been corrected by moving the read after the break.
Thanks to Jeroen who tested the patch (also with high workload).
Interrupts are down to normal and there are no obvious side
effects.
The attached patch is against kernel 2.6.11-rc2. A copy has been
sent to Donald Becker but unfortunately no response arrived.
Comments are very much appreciated.
Best regards,
-andi
--- sundance.c.orig 2005-01-22 02:48:26.0 +0100
+++ sundance.c 2005-01-28 19:55:59.0 +0100
@@ -1210,9 +1210,11 @@
}
/* Yup, this is a documentation bug. It cost
me *hours*. */
iowrite16 (0, ioaddr + TxStatus);
- tx_status = ioread16 (ioaddr + TxStatus);
- if (tx_cnt < 0)
+ if (tx_cnt < 0) {
+ iowrite32(5000, ioaddr + DownCounter);
break;
+ }
+ tx_status = ioread16 (ioaddr + TxStatus);
}
hw_frame_id = (tx_status >> 8) & 0xff;
} else {
@@ -1278,7 +1280,6 @@
if (netif_msg_intr(np))
printk(KERN_DEBUG "%s: exiting interrupt, status=%#4.4x.\n",
dev->name, ioread16(ioaddr + IntrStatus));
- iowrite32(5000, ioaddr + DownCounter);
return IRQ_RETVAL(handled);
}
--
| Andreas Maier University of Salzburg |
| ([EMAIL PROTECTED]) Department of Computing Sciences |
| Tel. +43/662/8044-6339Jakob Haringerstr. 2 |
| Fax. +43/662/8044-611 5020 Salzburg / Austria, Europe |
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[PATCH] sundance.c: high interrupt load [resent]
In at least some versions of Kernel 2.6 (2.6.8.1, 2.6.11-rc2)
the driver drivers/net/sundance.c creates high interrupt load
(~ 100 interrupts per second) even in case of no network traffic
at all.
It seems that some sort of TX overflow handling is misplaced
and triggers interrupts very often even in case of no data to
send. The TX overflow handling has been moved to a more
appropriate place.
While there, an off by one error of reading the TX status has
also been corrected by moving the read after the break.
Thanks to Jeroen who tested the patch (also with high workload).
Interrupts are down to normal and there are no obvious side
effects.
The attached patch is against kernel 2.6.11-rc2. A copy has been
sent to Donald Becker but unfortunately no response arrived.
Comments are very much appreciated.
Best regards,
-andi
--- sundance.c.orig 2005-01-22 02:48:26.0 +0100
+++ sundance.c 2005-01-28 19:55:59.0 +0100
@@ -1210,9 +1210,11 @@
}
/* Yup, this is a documentation bug. It cost
me *hours*. */
iowrite16 (0, ioaddr + TxStatus);
- tx_status = ioread16 (ioaddr + TxStatus);
- if (tx_cnt 0)
+ if (tx_cnt 0) {
+ iowrite32(5000, ioaddr + DownCounter);
break;
+ }
+ tx_status = ioread16 (ioaddr + TxStatus);
}
hw_frame_id = (tx_status 8) 0xff;
} else {
@@ -1278,7 +1280,6 @@
if (netif_msg_intr(np))
printk(KERN_DEBUG %s: exiting interrupt, status=%#4.4x.\n,
dev-name, ioread16(ioaddr + IntrStatus));
- iowrite32(5000, ioaddr + DownCounter);
return IRQ_RETVAL(handled);
}
--
| Andreas Maier University of Salzburg |
| ([EMAIL PROTECTED]) Department of Computing Sciences |
| Tel. +43/662/8044-6339Jakob Haringerstr. 2 |
| Fax. +43/662/8044-611 5020 Salzburg / Austria, Europe |
-
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
