2010-12-12 10:15:33

by Eliad Peller

Subject: [PATCH] wl12xx: allow runtime changing of debug_level

Currently, the debug level is set in compilation time (by the DEBUG_LEVEL
const). This method has the advantage of compiling only the relevant
messages, while optimizing out the unused ones.

In order to allow runtime control over the debug_level, while optimizing
out messages when debug messages are not needed, we combine some methods:
1. use dynamic_debug (pr_debug) rather then printk.
2. add debug_level module param in order to set debug level during insmod.
3. add debug_level sysfs file in order to allow dynamic control over the
debug level.

Since patches for pr_debug_hex_dump() implementation haven't been applied yet,
we are still temporarly using print_hex_dump().

Signed-off-by: Eliad Peller <[email protected]>
---
drivers/net/wireless/wl12xx/debugfs.c | 5 +++++
drivers/net/wireless/wl12xx/main.c | 5 +++++
drivers/net/wireless/wl12xx/wl12xx.h | 19 ++++++++++---------
3 files changed, 20 insertions(+), 9 deletions(-)

diff --git a/drivers/net/wireless/wl12xx/debugfs.c b/drivers/net/wireless/wl12xx/debugfs.c
index 8106a6c..c2cd580 100644
--- a/drivers/net/wireless/wl12xx/debugfs.c
+++ b/drivers/net/wireless/wl12xx/debugfs.c
@@ -401,6 +401,11 @@ static int wl1271_debugfs_add_files(struct wl1271 *wl)

DEBUGFS_ADD(gpio_power, wl->rootdir);

+ entry = debugfs_create_x32("debug_level", 0600, wl->rootdir,
+ &wl12xx_debug_level);
+ if (!entry || IS_ERR(entry))
+ goto err;
+
return 0;

err:
diff --git a/drivers/net/wireless/wl12xx/main.c b/drivers/net/wireless/wl12xx/main.c
index dc3a093..3428c45 100644
--- a/drivers/net/wireless/wl12xx/main.c
+++ b/drivers/net/wireless/wl12xx/main.c
@@ -2806,6 +2806,11 @@ int wl1271_free_hw(struct wl1271 *wl)
}
EXPORT_SYMBOL_GPL(wl1271_free_hw);

+u32 wl12xx_debug_level;
+EXPORT_SYMBOL_GPL(wl12xx_debug_level);
+module_param_named(debug_level, wl12xx_debug_level, uint, DEBUG_NONE);
+MODULE_PARM_DESC(debug_level, "wl12xx debugging level");
+
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Luciano Coelho <[email protected]>");
MODULE_AUTHOR("Juuso Oikarinen <[email protected]>");
diff --git a/drivers/net/wireless/wl12xx/wl12xx.h b/drivers/net/wireless/wl12xx/wl12xx.h
index e904c72..07c2297 100644
--- a/drivers/net/wireless/wl12xx/wl12xx.h
+++ b/drivers/net/wireless/wl12xx/wl12xx.h
@@ -60,31 +60,32 @@ enum {
DEBUG_ALL = ~0,
};

-#define DEBUG_LEVEL (DEBUG_NONE)
+extern u32 wl12xx_debug_level;

#define DEBUG_DUMP_LIMIT 1024

#define wl1271_error(fmt, arg...) \
- printk(KERN_ERR DRIVER_PREFIX "ERROR " fmt "\n", ##arg)
+ pr_err(DRIVER_PREFIX "ERROR " fmt "\n", ##arg)

#define wl1271_warning(fmt, arg...) \
- printk(KERN_WARNING DRIVER_PREFIX "WARNING " fmt "\n", ##arg)
+ pr_warning(DRIVER_PREFIX "WARNING " fmt "\n", ##arg)

#define wl1271_notice(fmt, arg...) \
- printk(KERN_INFO DRIVER_PREFIX fmt "\n", ##arg)
+ pr_info(DRIVER_PREFIX fmt "\n", ##arg)

#define wl1271_info(fmt, arg...) \
- printk(KERN_DEBUG DRIVER_PREFIX fmt "\n", ##arg)
+ pr_info(DRIVER_PREFIX fmt "\n", ##arg)

#define wl1271_debug(level, fmt, arg...) \
do { \
- if (level & DEBUG_LEVEL) \
- printk(KERN_DEBUG DRIVER_PREFIX fmt "\n", ##arg); \
+ if (level & wl12xx_debug_level) \
+ pr_debug(DRIVER_PREFIX fmt "\n", ##arg); \
} while (0)

+/* TODO: use pr_debug_hex_dump when it will be available */
#define wl1271_dump(level, prefix, buf, len) \
do { \
- if (level & DEBUG_LEVEL) \
+ if (level & wl12xx_debug_level) \
print_hex_dump(KERN_DEBUG, DRIVER_PREFIX prefix, \
DUMP_PREFIX_OFFSET, 16, 1, \
buf, \
@@ -94,7 +95,7 @@ enum {

#define wl1271_dump_ascii(level, prefix, buf, len) \
do { \
- if (level & DEBUG_LEVEL) \
+ if (level & wl12xx_debug_level) \
print_hex_dump(KERN_DEBUG, DRIVER_PREFIX prefix, \
DUMP_PREFIX_OFFSET, 16, 1, \
buf, \
--
1.7.0.4

2010-12-15 13:13:44

by Luciano Coelho

Subject: Re: [PATCH] wl12xx: allow runtime changing of debug_level

On Sun, 2010-12-12 at 12:15 +0200, ext Eliad Peller wrote:
> Currently, the debug level is set in compilation time (by the DEBUG_LEVEL
> const). This method has the advantage of compiling only the relevant
> messages, while optimizing out the unused ones.
>
> In order to allow runtime control over the debug_level, while optimizing
> out messages when debug messages are not needed, we combine some methods:
> 1. use dynamic_debug (pr_debug) rather then printk.
> 2. add debug_level module param in order to set debug level during insmod.
> 3. add debug_level sysfs file in order to allow dynamic control over the
> debug level.
>
> Since patches for pr_debug_hex_dump() implementation haven't been applied yet,
> we are still temporarly using print_hex_dump().
>
> Signed-off-by: Eliad Peller <[email protected]>
> ---

Applied, thanks!


--
Cheers,
Luca.