[PATCH] 2.5: ewrk3 cli/sti removal by VDA

[PATCH] 2.5: ewrk3 cli/sti removal by VDA

[Adam Kropelin]

Below is a patch from Denis Vlasenko <vda@port.imtp.ilyichevsk.odessa.ua> which
removes cli/sti in the ewrk3 driver. It tests out fine here with SMP & preempt.

Applies against 2.5.34 + ewrk3-ethtool patch. Also applies without ethtool patch
with some offsets.

(Denis, I took the liberty of forwarding this to Jeff since it works fine for me
and the driver is pretty much useless without it. Scream if you don't want it
applied...)

--Adam
 
--- linux-2.5.43-mm1/drivers/net/ewrk3.c.orig	Fri Oct 18 21:55:44 2002
+++ linux-2.5.43-mm1/drivers/net/ewrk3.c	Fri Oct 18 22:02:41 2002
@@ -940,6 +940,7 @@
 	spin_unlock(&lp->hw_lock);
 }
 
+/* Called with lp->hw_lock held */
 static int ewrk3_rx(struct net_device *dev)
 {
 	struct ewrk3_private *lp = (struct ewrk3_private *) dev->priv;
@@ -1065,8 +1066,9 @@
 }
 
 /*
-   ** Buffer sent - check for TX buffer errors.
- */
+** Buffer sent - check for TX buffer errors.
+** Called with lp->hw_lock held
+*/
 static int ewrk3_tx(struct net_device *dev)
 {
 	struct ewrk3_private *lp = (struct ewrk3_private *) dev->priv;
@@ -1830,6 +1832,7 @@
 	u_long iobase = dev->base_addr;
 	int i, j, status = 0;
 	u_char csr;
+	unsigned long flags;
 	union ewrk3_addr {
 		u_char addr[HASH_TABLE_LEN * ETH_ALEN];
 		u_short val[(HASH_TABLE_LEN * ETH_ALEN) >> 1];
@@ -1953,19 +1956,26 @@
 		}
 
 		break;
-	case EWRK3_GET_STATS:	/* Get the driver statistics */
-		cli();
-		ioc->len = sizeof(lp->pktStats);
-		if (copy_to_user(ioc->data, &lp->pktStats, ioc->len))
-			status = -EFAULT;
-		sti();
+	case EWRK3_GET_STATS: { /* Get the driver statistics */
+		typeof(lp->pktStats) *tmp_stats =
+        		kmalloc(sizeof(lp->pktStats), GFP_KERNEL);
+		if (!tmp_stats) return -ENOMEM;
 
+		spin_lock_irqsave(&lp->hw_lock, flags);
+		memcpy(tmp_stats, &lp->pktStats, sizeof(lp->pktStats));
+		spin_unlock_irqrestore(&lp->hw_lock, flags);
+
+		ioc->len = sizeof(lp->pktStats);
+		if (copy_to_user(ioc->data, tmp_stats, sizeof(lp->pktStats)))
+    			status = -EFAULT;
+		kfree(tmp_stats);
 		break;
+	}
 	case EWRK3_CLR_STATS:	/* Zero out the driver statistics */
 		if (capable(CAP_NET_ADMIN)) {
-			cli();
+			spin_lock_irqsave(&lp->hw_lock, flags);
 			memset(&lp->pktStats, 0, sizeof(lp->pktStats));
-			sti();
+			spin_unlock_irqrestore(&lp->hw_lock,flags);
 		} else {
 			status = -EPERM;
 		}

Re: [PATCH] 2.5: ewrk3 cli/sti removal by VDA

[Adam Kropelin]

> Applies against 2.5.34 + ewrk3-ethtool patch. Also applies without ethtool patch
                      ^^
2.5.43, of course.

--Adam

Re: [PATCH] 2.5: ewrk3 cli/sti removal by VDA

[Denis Vlasenko]

On 19 October 2002 02:13, Adam Kropelin wrote:
> Below is a patch from Denis Vlasenko
> <vda@port.imtp.ilyichevsk.odessa.ua> which removes cli/sti in the
> ewrk3 driver. It tests out fine here with SMP & preempt.

Thanks. SMP & preempt testing is most important.

> Applies against 2.5.34 + ewrk3-ethtool patch. Also applies without
> ethtool patch with some offsets.
>
> (Denis, I took the liberty of forwarding this to Jeff since it works
> fine for me and the driver is pretty much useless without it. Scream
> if you don't want it applied...)

No problem.

I just want drivers to be _thoroughly_ tested while we fix them since
a flaky driver can spoil all efforts spent on making bulletproof core
kernel.

What methods do folks use to break NIC drivers?
It would be nice to have crash-my-nic toolset :-)

BTW, I wanted to learn about pktgen, but there's no pktgen in 2.5
(don't know why).
--
vda

Re: [PATCH] 2.5: ewrk3 cli/sti removal by VDA

[Jeff Garzik]

[-- Attachment #1: Type: text/plain, Size: 612 bytes --]

Adam Kropelin wrote:
> Below is a patch from Denis Vlasenko <vda@port.imtp.ilyichevsk.odessa.ua> which
> removes cli/sti in the ewrk3 driver. It tests out fine here with SMP & preempt.
> 
> Applies against 2.5.34 + ewrk3-ethtool patch. Also applies without ethtool patch
> with some offsets.
> 
> (Denis, I took the liberty of forwarding this to Jeff since it works fine for me
> and the driver is pretty much useless without it. Scream if you don't want it
> applied...)

Applied and then cleaned up...  ETHTOOL_PHYS_ID needs to use 
schedule_timeout(), and using typeof should be avoided.

New patch attached.

[-- Attachment #2: patch --]
[-- Type: text/plain, Size: 3815 bytes --]

# This is a BitKeeper generated patch for the following project:
# Project Name: Linux kernel tree
# This patch format is intended for GNU patch command version 2.5 or higher.
# This patch includes the following deltas:
#	           ChangeSet	1.751   -> 1.752  
#	 drivers/net/ewrk3.c	1.15    -> 1.16   
#
# The following is the BitKeeper ChangeSet Log
# --------------------------------------------
# 02/10/21	jgarzik@redhat.com	1.752
# Remove cli/sti from ewrk3 net driver.
# Also, comment out ETHTOOL_PHYS_ID until its sleeping is fixed.
#   
# Originally by Denis Vlasenko, then via Adam Kropelin, and
# finally cleaned up by me.
# --------------------------------------------
#
diff -Nru a/drivers/net/ewrk3.c b/drivers/net/ewrk3.c
--- a/drivers/net/ewrk3.c	Mon Oct 21 20:35:04 2002
+++ b/drivers/net/ewrk3.c	Mon Oct 21 20:35:04 2002
@@ -262,20 +262,22 @@
 #define EWRK3_PKT_BIN_SZ  128	/* Should be >=100 unless you
 				   increase EWRK3_PKT_STAT_SZ */
 
+struct ewrk3_stats {
+	u32 bins[EWRK3_PKT_STAT_SZ];
+	u32 unicast;
+	u32 multicast;
+	u32 broadcast;
+	u32 excessive_collisions;
+	u32 tx_underruns;
+	u32 excessive_underruns;
+};
+
 struct ewrk3_private {
 	char adapter_name[80];	/* Name exported to /proc/ioports */
 	u_long shmem_base;	/* Shared memory start address */
 	u_long shmem_length;	/* Shared memory window length */
 	struct net_device_stats stats;	/* Public stats */
-	struct {
-		u32 bins[EWRK3_PKT_STAT_SZ];	/* Private stats counters */
-		u32 unicast;
-		u32 multicast;
-		u32 broadcast;
-		u32 excessive_collisions;
-		u32 tx_underruns;
-		u32 excessive_underruns;
-	} pktStats;
+	struct ewrk3_stats pktStats; /* Private stats counters */
 	u_char irq_mask;	/* Adapter IRQ mask bits */
 	u_char mPage;		/* Maximum 2kB Page number */
 	u_char lemac;		/* Chip rev. level */
@@ -940,6 +942,7 @@
 	spin_unlock(&lp->hw_lock);
 }
 
+/* Called with lp->hw_lock held */
 static int ewrk3_rx(struct net_device *dev)
 {
 	struct ewrk3_private *lp = (struct ewrk3_private *) dev->priv;
@@ -1065,8 +1068,9 @@
 }
 
 /*
-   ** Buffer sent - check for TX buffer errors.
- */
+** Buffer sent - check for TX buffer errors.
+** Called with lp->hw_lock held
+*/
 static int ewrk3_tx(struct net_device *dev)
 {
 	struct ewrk3_private *lp = (struct ewrk3_private *) dev->priv;
@@ -1760,6 +1764,7 @@
 		return 0;
 	}
 
+#ifdef BROKEN
 	/* Blink LED for identification */
 	case ETHTOOL_PHYS_ID: {
 		struct ethtool_value edata;
@@ -1813,6 +1818,7 @@
 		spin_unlock_irqrestore(&lp->hw_lock, flags);
 		return ret;
 	}
+#endif /* BROKEN */
 
 	}
 
@@ -1830,6 +1836,7 @@
 	u_long iobase = dev->base_addr;
 	int i, j, status = 0;
 	u_char csr;
+	unsigned long flags;
 	union ewrk3_addr {
 		u_char addr[HASH_TABLE_LEN * ETH_ALEN];
 		u_short val[(HASH_TABLE_LEN * ETH_ALEN) >> 1];
@@ -1953,19 +1960,26 @@
 		}
 
 		break;
-	case EWRK3_GET_STATS:	/* Get the driver statistics */
-		cli();
-		ioc->len = sizeof(lp->pktStats);
-		if (copy_to_user(ioc->data, &lp->pktStats, ioc->len))
-			status = -EFAULT;
-		sti();
+	case EWRK3_GET_STATS: { /* Get the driver statistics */
+		struct ewrk3_stats *tmp_stats =
+        		kmalloc(sizeof(lp->pktStats), GFP_KERNEL);
+		if (!tmp_stats) return -ENOMEM;
 
+		spin_lock_irqsave(&lp->hw_lock, flags);
+		memcpy(tmp_stats, &lp->pktStats, sizeof(lp->pktStats));
+		spin_unlock_irqrestore(&lp->hw_lock, flags);
+
+		ioc->len = sizeof(lp->pktStats);
+		if (copy_to_user(ioc->data, tmp_stats, sizeof(lp->pktStats)))
+    			status = -EFAULT;
+		kfree(tmp_stats);
 		break;
+	}
 	case EWRK3_CLR_STATS:	/* Zero out the driver statistics */
 		if (capable(CAP_NET_ADMIN)) {
-			cli();
+			spin_lock_irqsave(&lp->hw_lock, flags);
 			memset(&lp->pktStats, 0, sizeof(lp->pktStats));
-			sti();
+			spin_unlock_irqrestore(&lp->hw_lock,flags);
 		} else {
 			status = -EPERM;
 		}

Re: [PATCH] 2.5: ewrk3 cli/sti removal by VDA

[Adam Kropelin]

On Mon, Oct 21, 2002 at 08:36:17PM -0400, Jeff Garzik wrote:
> Adam Kropelin wrote:
> >Below is a patch from Denis Vlasenko <vda@port.imtp.ilyichevsk.odessa.ua> 
> >which
> >removes cli/sti in the ewrk3 driver. It tests out fine here with SMP & 
> >preempt.
> 
> Applied and then cleaned up...  ETHTOOL_PHYS_ID needs to use 
> schedule_timeout(), and using typeof should be avoided.

The patch below (against yours) should fix ETHTOOL_PHYS_ID again. Let me
know if I got it wrong. Was my prior use of
wait_event_interruptible_tiumeout actually broken or rather
just a lot more complicated than it needed to be?

I didn't find any use of typeof. If you point me to it I'll fix that up,
too.

Thanks for bearing with me. I'm climbing the clue-ladder as fast as I
can... ;)

--Adam

--- linux-2.5.44/drivers/net/ewrk3.c	Mon Oct 21 22:01:01 2002
+++ linux-2.5.44/drivers/net/ewrk3.c.new	Mon Oct 21 21:58:13 2002
@@ -1759,23 +1759,18 @@
 		return 0;
 	}
 
-#ifdef BROKEN
 	/* Blink LED for identification */
 	case ETHTOOL_PHYS_ID: {
 		struct ethtool_value edata;
 		u_long flags;
-		long delay, ret;
+		long ret=0;
 		u_char cr;
 		int count;
-		wait_queue_head_t wait;
-
-		init_waitqueue_head(&wait);
 
 		if (copy_from_user(&edata, useraddr, sizeof(edata)))
 			return -EFAULT;
 
 		/* Toggle LED 4x per second */
-		delay = HZ >> 2;
 		count = edata.data << 2;
 
 		spin_lock_irqsave(&lp->hw_lock, flags);
@@ -1796,24 +1791,21 @@
 
 			/* Wait a little while */
 			spin_unlock_irqrestore(&lp->hw_lock, flags);
-			ret = delay;
-			__wait_event_interruptible_timeout(wait, 0, ret);
+			set_current_state(TASK_INTERRUPTIBLE);
+			ret = schedule_timeout(HZ>>2);
 			spin_lock_irqsave(&lp->hw_lock, flags);
 
 			/* Exit if we got a signal */
-			if (ret == -ERESTARTSYS)
-				goto out;
+			if (ret)
+				break;
 		}
 
-		ret = 0;
-out:
 		lp->led_mask = CR_LED;
 		cr = inb(EWRK3_CR);
 		outb(cr & ~CR_LED, EWRK3_CR);
 		spin_unlock_irqrestore(&lp->hw_lock, flags);
-		return ret;
+		return ret ? -ERESTARTSYS : 0;
 	}
-#endif /* BROKEN */
 
 	}
 

Re: [PATCH] 2.5: ewrk3 cli/sti removal by VDA

[Jeff Garzik]

Adam Kropelin wrote:
> On Mon, Oct 21, 2002 at 08:36:17PM -0400, Jeff Garzik wrote:
> 
>>Adam Kropelin wrote:
>>
>>>Below is a patch from Denis Vlasenko <vda@port.imtp.ilyichevsk.odessa.ua> 
>>>which
>>>removes cli/sti in the ewrk3 driver. It tests out fine here with SMP & 
>>>preempt.
>>
>>Applied and then cleaned up...  ETHTOOL_PHYS_ID needs to use 
>>schedule_timeout(), and using typeof should be avoided.
> 
> 
> The patch below (against yours) should fix ETHTOOL_PHYS_ID again. Let me
> know if I got it wrong. Was my prior use of
> wait_event_interruptible_tiumeout actually broken or rather
> just a lot more complicated than it needed to be?

broken in 2.4 -and- more complicated than it needed to be in 2.5.x ;-)


> I didn't find any use of typeof. If you point me to it I'll fix that up,
> too.

I fixed it up... grep your original patch.  typeof() was used because 
lp->pktStats was an anonymous structure with no defined typename.  I 
moved the struct out and gave it a name.


> Thanks for bearing with me. I'm climbing the clue-ladder as fast as I
> can... ;)

hehe, thanks for doing the patches and the testing... :)


> --- linux-2.5.44/drivers/net/ewrk3.c	Mon Oct 21 22:01:01 2002
> +++ linux-2.5.44/drivers/net/ewrk3.c.new	Mon Oct 21 21:58:13 2002

quick review says it looks good, I'll make another pass over it with my 
brain switched on, and apply or comment as it warrants :)

	Jeff

Re: [PATCH] 2.5: ewrk3 cli/sti removal by VDA

[Jeff Garzik]

Adam Kropelin wrote:

>On Mon, Oct 21, 2002 at 08:36:17PM -0400, Jeff Garzik wrote:
>  
>
>>Adam Kropelin wrote:
>>    
>>
>>>Below is a patch from Denis Vlasenko <vda@port.imtp.ilyichevsk.odessa.ua> 
>>>which
>>>removes cli/sti in the ewrk3 driver. It tests out fine here with SMP & 
>>>preempt.
>>>      
>>>
>>Applied and then cleaned up...  ETHTOOL_PHYS_ID needs to use 
>>schedule_timeout(), and using typeof should be avoided.
>>    
>>
>
>The patch below (against yours) should fix ETHTOOL_PHYS_ID again. Let me
>know if I got it wrong. Was my prior use of
>wait_event_interruptible_tiumeout actually broken or rather
>just a lot more complicated than it needed to be?
>
>I didn't find any use of typeof. If you point me to it I'll fix that up,
>too.
>
>Thanks for bearing with me. I'm climbing the clue-ladder as fast as I
>can... ;)
>
>--Adam
>
>--- linux-2.5.44/drivers/net/ewrk3.c	Mon Oct 21 22:01:01 2002
>+++ linux-2.5.44/drivers/net/ewrk3.c.new	Mon Oct 21 21:58:13 2002
>@@ -1759,23 +1759,18 @@
> 		return 0;
> 	}
> 
>-#ifdef BROKEN
> 	/* Blink LED for identification */
> 	case ETHTOOL_PHYS_ID: {
> 		struct ethtool_value edata;
> 		u_long flags;
>-		long delay, ret;
>+		long ret=0;
> 		u_char cr;
> 		int count;
>-		wait_queue_head_t wait;
>-
>-		init_waitqueue_head(&wait);
> 
> 		if (copy_from_user(&edata, useraddr, sizeof(edata)))
> 			return -EFAULT;
> 
> 		/* Toggle LED 4x per second */
>-		delay = HZ >> 2;
> 		count = edata.data << 2;
> 
> 		spin_lock_irqsave(&lp->hw_lock, flags);
>@@ -1796,24 +1791,21 @@
> 
> 			/* Wait a little while */
> 			spin_unlock_irqrestore(&lp->hw_lock, flags);
>-			ret = delay;
>-			__wait_event_interruptible_timeout(wait, 0, ret);
>+			set_current_state(TASK_INTERRUPTIBLE);
>+			ret = schedule_timeout(HZ>>2);
>  
>


close -- if schedule_timeout() returns greater than zero, that number is 
the remaining jiffies that schedule_timeout _should_ have slept, but did 
not.  Ideally you need to call it in a loop, that decrements a variable 
based on schedule_timeout return code.

Re: [PATCH] 2.5: ewrk3 cli/sti removal by VDA

[Adam Kropelin]

On Fri, Oct 25, 2002 at 06:45:04PM -0400, Jeff Garzik wrote:
> Adam Kropelin wrote:
> >
> >			/* Wait a little while */
> >			spin_unlock_irqrestore(&lp->hw_lock, flags);
> >-			ret = delay;
> >-			__wait_event_interruptible_timeout(wait, 0, ret);
> >+			set_current_state(TASK_INTERRUPTIBLE);
> >+			ret = schedule_timeout(HZ>>2);
> >
> 
> close -- if schedule_timeout() returns greater than zero, that number is 
> the remaining jiffies that schedule_timeout _should_ have slept, but did 
> not.  Ideally you need to call it in a loop, that decrements a variable 
> based on schedule_timeout return code.

My assumption was that the only case in which schedule_timeout() would
return without completing the sleep is if the process was delivered a
signal. So I break the loop immediately in that case. I presume from
your explanation that schedule_timeout() may return for some other reason
(out of curiousity, what?)...and in that case I need to check for a
pending signal, exit if there is one, otherwise schedule_timeout() for
the remaining time. Am I getting warmer?

--Adam

Re: [PATCH] 2.5: ewrk3 cli/sti removal by VDA

[Adam Kropelin]

On Fri, Oct 25, 2002 at 06:45:04PM -0400, Jeff Garzik wrote:
> Adam Kropelin wrote:
> >			spin_unlock_irqrestore(&lp->hw_lock, flags);
> >-			ret = delay;
> >-			__wait_event_interruptible_timeout(wait, 0, ret);
> >+			set_current_state(TASK_INTERRUPTIBLE);
> >+			ret = schedule_timeout(HZ>>2);
> 
> close -- if schedule_timeout() returns greater than zero, that number is 
> the remaining jiffies that schedule_timeout _should_ have slept, but did 
> not.  Ideally you need to call it in a loop, that decrements a variable 
> based on schedule_timeout return code.

Try this one on for size...

--Adam


--- linux-2.5.45-virgin/drivers/net/ewrk3.c	Wed Oct 30 22:55:10 2002
+++ linux-2.5.45/drivers/net/ewrk3.c	Fri Nov  1 17:15:13 2002
@@ -1759,23 +1759,18 @@
 		return 0;
 	}
 
-#ifdef BROKEN
 	/* Blink LED for identification */
 	case ETHTOOL_PHYS_ID: {
 		struct ethtool_value edata;
 		u_long flags;
-		long delay, ret;
+		long ret=0;
 		u_char cr;
 		int count;
-		wait_queue_head_t wait;
-
-		init_waitqueue_head(&wait);
 
 		if (copy_from_user(&edata, useraddr, sizeof(edata)))
 			return -EFAULT;
 
 		/* Toggle LED 4x per second */
-		delay = HZ >> 2;
 		count = edata.data << 2;
 
 		spin_lock_irqsave(&lp->hw_lock, flags);
@@ -1796,24 +1791,24 @@
 
 			/* Wait a little while */
 			spin_unlock_irqrestore(&lp->hw_lock, flags);
-			ret = delay;
-			__wait_event_interruptible_timeout(wait, 0, ret);
+			ret = HZ>>2;
+			while(ret && !signal_pending(current)) {
+				set_current_state(TASK_INTERRUPTIBLE);
+				ret = schedule_timeout(ret);
+			}
 			spin_lock_irqsave(&lp->hw_lock, flags);
 
 			/* Exit if we got a signal */
-			if (ret == -ERESTARTSYS)
-				goto out;
+			if (ret)
+				break;
 		}
 
-		ret = 0;
-out:
 		lp->led_mask = CR_LED;
 		cr = inb(EWRK3_CR);
 		outb(cr & ~CR_LED, EWRK3_CR);
 		spin_unlock_irqrestore(&lp->hw_lock, flags);
-		return ret;
+		return ret ? -ERESTARTSYS : 0;
 	}
-#endif /* BROKEN */
 
 	}