[HOSTAP] Make debug a run-time option

[HOSTAP] Make debug a run-time option

[Kyle McMartin]

Build-time debugging isn't overly useful for distro kernel folks, nor is
enabling huge amounts of debug spew by default. Provide the option of
enabling debugging with module parameters.

Signed-off-by: Kyle McMartin <kyle-Z7WLFzj8eWMS+FvcfC7Uqw@public.gmane.org>
---
diff --git a/drivers/net/wireless/hostap/hostap_info.c b/drivers/net/wireless/hostap/hostap_info.c
index b6a02a0..6eb8d88 100644
--- a/drivers/net/wireless/hostap/hostap_info.c
+++ b/drivers/net/wireless/hostap/hostap_info.c
@@ -96,7 +96,6 @@ static void prism2_info_commtallies(local_info_t *local, unsigned char *buf,
 
 
 #ifndef PRISM2_NO_STATION_MODES
-#ifndef PRISM2_NO_DEBUG
 static const char* hfa384x_linkstatus_str(u16 linkstatus)
 {
 	switch (linkstatus) {
@@ -116,7 +115,6 @@ static const char* hfa384x_linkstatus_str(u16 linkstatus)
 		return "Unknown";
 	}
 }
-#endif /* PRISM2_NO_DEBUG */
 
 
 /* Called only as a tasklet (software IRQ) */
@@ -362,9 +360,7 @@ void hostap_info_process(local_info_t *local, struct sk_buff *skb)
 	struct hfa384x_info_frame *info;
 	unsigned char *buf;
 	int left;
-#ifndef PRISM2_NO_DEBUG
 	int i;
-#endif /* PRISM2_NO_DEBUG */
 
 	info = (struct hfa384x_info_frame *) skb->data;
 	buf = skb->data + sizeof(*info);
@@ -389,16 +385,16 @@ void hostap_info_process(local_info_t *local, struct sk_buff *skb)
 		break;
 #endif /* PRISM2_NO_STATION_MODES */
 
-#ifndef PRISM2_NO_DEBUG
 	default:
-		PDEBUG(DEBUG_EXTRA, "%s: INFO - len=%d type=0x%04x\n",
-		       local->dev->name, info->len, info->type);
-		PDEBUG(DEBUG_EXTRA, "Unknown info frame:");
-		for (i = 0; i < (left < 100 ? left : 100); i++)
-			PDEBUG2(DEBUG_EXTRA, " %02x", buf[i]);
-		PDEBUG2(DEBUG_EXTRA, "\n");
+		if (hostap_debug) {
+			PDEBUG(DEBUG_EXTRA, "%s: INFO - len=%d type=0x%04x\n",
+			       local->dev->name, info->len, info->type);
+			PDEBUG(DEBUG_EXTRA, "Unknown info frame:");
+			for (i = 0; i < (left < 100 ? left : 100); i++)
+				PDEBUG2(DEBUG_EXTRA, " %02x", buf[i]);
+			PDEBUG2(DEBUG_EXTRA, "\n");
+		}
 		break;
-#endif /* PRISM2_NO_DEBUG */
 	}
 }
 
diff --git a/drivers/net/wireless/hostap/hostap_main.c b/drivers/net/wireless/hostap/hostap_main.c
index 9077e6e..2015ab3 100644
--- a/drivers/net/wireless/hostap/hostap_main.c
+++ b/drivers/net/wireless/hostap/hostap_main.c
@@ -46,6 +46,14 @@ MODULE_VERSION(PRISM2_VERSION);
 /* FIX: */
 #define PRISM2_MAX_MTU (PRISM2_MAX_FRAME_SIZE - (6 /* LLC */ + 8 /* WEP */))
 
+unsigned int hostap_debug = 0;
+module_param(hostap_debug, uint, 0644);
+MODULE_PARM_DESC(hostap_debug, "Enable verbose debugging output");
+EXPORT_SYMBOL(hostap_debug);
+
+unsigned int hostap_debug_mask = DEBUG_MASK;
+module_param(hostap_debug_mask, uint, 0644);
+EXPORT_SYMBOL(hostap_debug_mask);
 
 struct net_device * hostap_add_interface(struct local_info *local,
 					 int type, int rtnl_locked,
diff --git a/drivers/net/wireless/hostap/hostap_wlan.h b/drivers/net/wireless/hostap/hostap_wlan.h
index 87a54aa..e318f26 100644
--- a/drivers/net/wireless/hostap/hostap_wlan.h
+++ b/drivers/net/wireless/hostap/hostap_wlan.h
@@ -923,8 +923,6 @@ struct hostap_skb_tx_data {
 };
 
 
-#ifndef PRISM2_NO_DEBUG
-
 #define DEBUG_FID BIT(0)
 #define DEBUG_PS BIT(1)
 #define DEBUG_FLOW BIT(2)
@@ -935,16 +933,12 @@ struct hostap_skb_tx_data {
 #define DEBUG_PS2 BIT(7)
 #define DEBUG_MASK (DEBUG_PS | DEBUG_AP | DEBUG_HW | DEBUG_EXTRA)
 #define PDEBUG(n, args...) \
-do { if ((n) & DEBUG_MASK) printk(KERN_DEBUG args); } while (0)
+do { if (hostap_debug && ((n) & hostap_debug_mask)) printk(KERN_DEBUG args); } while (0)
 #define PDEBUG2(n, args...) \
-do { if ((n) & DEBUG_MASK) printk(args); } while (0)
-
-#else /* PRISM2_NO_DEBUG */
-
-#define PDEBUG(n, args...)
-#define PDEBUG2(n, args...)
+do { if (hostap_debug && ((n) & hostap_debug_mask)) printk(args); } while (0)
 
-#endif /* PRISM2_NO_DEBUG */
+extern unsigned int hostap_debug;
+extern unsigned int hostap_debug_mask;
 
 enum { BAP0 = 0, BAP1 = 1 };
 

Re: Make debug a run-time option

[Jouni Malinen]

On Wed, Mar 14, 2007 at 12:03:56PM -0400, Kyle McMartin wrote:
> Build-time debugging isn't overly useful for distro kernel folks, nor is
> enabling huge amounts of debug spew by default. Provide the option of
> enabling debugging with module parameters.

While I understand that it would be difficult to change the debug level
options with binary distributions, I'm not sure whether I would like to
see these changes going in. PRISM2_NO_DEBUG was added to make it
possible to reduce the driver size considerably. In addition, the change
to the default debug categories (i.e., disable all) may make it more
difficult to understand reported issues. I would be more open to
disabling debug messages one-by-one if there is something specific that
can be agreed to cause more harm than benefit with extra output.

-- 
Jouni Malinen                                            PGP id EFC895FA

Re: [HOSTAP] Make debug a run-time option

[John W. Linville]

On Wed, Mar 14, 2007 at 05:17:42PM +0000, Jouni Malinen wrote:
> On Wed, Mar 14, 2007 at 12:03:56PM -0400, Kyle McMartin wrote:
> > Build-time debugging isn't overly useful for distro kernel folks, nor is
> > enabling huge amounts of debug spew by default. Provide the option of
> > enabling debugging with module parameters.
> 
> While I understand that it would be difficult to change the debug level
> options with binary distributions, I'm not sure whether I would like to
> see these changes going in. PRISM2_NO_DEBUG was added to make it
> possible to reduce the driver size considerably. In addition, the change

What about a combined approach?  The existing compile-time option
could remain while runtime restrictions could be added for when the
debug stuff is compiled into the driver?

John
-- 
John W. Linville
linville-2XuSBdqkA4R54TAoqtyWWQ@public.gmane.org

Re: [HOSTAP] Make debug a run-time option

[Jouni Malinen]

On Wed, Mar 14, 2007 at 03:48:00PM -0400, John W. Linville wrote:

> What about a combined approach?  The existing compile-time option
> could remain while runtime restrictions could be added for when the
> debug stuff is compiled into the driver?

I would be perfectly fine with doing that assuming the default behavior
is not changed with this patch (i.e., debugging would be enabled by
default). I would consider changing the default setting a separate issue
and for that, it might be more worthwhile approach to identify the debug
messages that are undesired by default than to disable everything.

-- 
Jouni Malinen                                            PGP id EFC895FA