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debug printk infrastructure -implement level controls

PATCH In review Jason Baron 2 participants 2 messages May 22, 2008 – May 27, 2008

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Jason Baron

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#0 lore raw

PATCH 2/8 debug printk infrastructure -implement level controls

Signed-off-by Jason Baron <[email protected]>
---
 include/linux/device.h         |   16 ++++++++
 include/linux/dynamic_printk.h |    9 +++++
 lib/dynamic_printk.c           |   78 +++++++++++++++++++++++++++++++++++++--
 3 files changed, 99 insertions(+), 4 deletions(-)
include/linux/device.h +16 -0
index 8f3ca1f..b1aae4d 100644
@@ -616,6 +616,22 @@ extern const char *dev_driver_string(struct device *dev);
 	({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; })
 #endif
 
+#ifdef CONFIG_PRINTK_DEBUG
+#define register_dev_dbg_handler(parent, type, max, init) \
+	__register_dev_dbg_handler(KBUILD_MODNAME, parent, type, max, init)
+#define dev_dbg_level(value, dev, format, ...) \
+	__dev_dbg_level(KBUILD_MODNAME, value, dev, format, ##__VA_ARGS__)
+#define dev_dbg_enabled(value) \
+	__dev_dbg_enabled(KBUILD_MODNAME, value)
+#else
+#define register_dev_dbg_handler(parent, type, max, init) \
+	({ if (0) __register_dev_dbg_handler(KBUILD_MODNAME, parent, type, max, init); 0; })
+#define dev_dbg_level(value, dev, format, ...) \
+	({ if (0) __dev_dbg_level(KBUILD_MODNAME, value, dev, format, ##__VA_ARGS__); 0; })
+#define dev_dbg_enabled(value) \
+	({ if (0) __dev_dbg_enabled(KBUILD_MODNAME, value); 0; })
+#endif
+
 #ifdef VERBOSE_DEBUG
 #define dev_vdbg	dev_dbg
 #else
include/linux/dynamic_printk.h +9 -0
index b1afef3..bb366b4 100644
@@ -7,6 +7,10 @@
 
 #define DYNAMIC_HASH_BITS 5
 #define FILE_TABLE_SIZE (1 << DYNAMIC_HASH_BITS)
+#define TYPE_LEVEL 1
+#define TYPE_FLAG 2
+
+struct device;
 
 struct mod_debug {
 	char *modname;

@@ -40,5 +44,10 @@ static inline unsigned int dynamic_name_hash(char *name)
         return (hash & ((1 << DYNAMIC_HASH_BITS) - 1));
 }
 
+int __register_dev_dbg_handler(char *mod_name, char *parent_name, int type, int max,
+				int init);
+void __dev_dbg_level(char *mod_name, int level, struct device *dev, char *fmt, ...);
+int __dev_dbg_enabled(char *modname, int value);
+
 #endif
 #endif
lib/dynamic_printk.c +74 -4

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Signature · 1 line
1.5.4.5
maintainer
#1 lore raw
Quoted 7 lines · On Thu, 22 May 2008 17:15:51 -0400 Jason Baron <[email protected]> wrote:
Signed-off-by Jason Baron <[email protected]>
---
 include/linux/device.h         |   16 ++++++++
 include/linux/dynamic_printk.h |    9 +++++
 lib/dynamic_printk.c           |   78 +++++++++++++++++++++++++++++++++++++--
 3 files changed, 99 insertions(+), 4 deletions(-)

no changelog...

Quoted 13 lines
include/linux/device.h +5 -0
index 8f3ca1f..b1aae4d 100644
@@ -616,6 +616,22 @@ extern const char *dev_driver_string(struct device *dev);
 	({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; })
 #endif
 
+#ifdef CONFIG_PRINTK_DEBUG
+#define register_dev_dbg_handler(parent, type, max, init) \
+	__register_dev_dbg_handler(KBUILD_MODNAME, parent, type, max, init)
+#define dev_dbg_level(value, dev, format, ...) \
+	__dev_dbg_level(KBUILD_MODNAME, value, dev, format, ##__VA_ARGS__)

include/linux/device.h extern const char *dev_driver_string(struct device *dev); · line 633

Quoted 10 lines
include/linux/device.h +10 -0
+#define dev_dbg_enabled(value) \
+	__dev_dbg_enabled(KBUILD_MODNAME, value)
+#else
+#define register_dev_dbg_handler(parent, type, max, init) \
+	({ if (0) __register_dev_dbg_handler(KBUILD_MODNAME, parent, type, max, init); 0; })
+#define dev_dbg_level(value, dev, format, ...) \
+	({ if (0) __dev_dbg_level(KBUILD_MODNAME, value, dev, format, ##__VA_ARGS__); 0; })
+#define dev_dbg_enabled(value) \
+	({ if (0) __dev_dbg_enabled(KBUILD_MODNAME, value); 0; })
+#endif

A major interface which we expect/hope thousands of developers will use. It will need documentation eventually, and we might as well add that now, to make review easier and more effective.

Quoted 23 lines
include/linux/device.h +0 -0
 #ifdef VERBOSE_DEBUG
 #define dev_vdbg	dev_dbg
 #else
include/linux/dynamic_printk.h +4 -0
index b1afef3..bb366b4 100644
@@ -7,6 +7,10 @@
 
 #define DYNAMIC_HASH_BITS 5
 #define FILE_TABLE_SIZE (1 << DYNAMIC_HASH_BITS)
+#define TYPE_LEVEL 1
+#define TYPE_FLAG 2
+
+struct device;
 
 struct mod_debug {
 	char *modname;
 
...

@@ -230,6 +292,14 @@ static ssize_t pr_debug_write(struct file *file, const char __user *buf,
 			}

include/linux/dynamic_printk.h static ssize_t pr_debug_write(struct file *file, const char __user *buf, · line 302

Quoted 10 lines
include/linux/dynamic_printk.h +8 -0
 			err = 0;
 		}
+	} else if (!strncmp("set level=", buffer, 10)) {
+		s = buffer + 10;
+		level = strsep(&s, " ");
+		s = strstrip(s);
+		if (elem = find_debug_file(s)) {
+			elem->level = simple_strtol(level, NULL, 10);
+			err = 0;
+		}

The first thing we zoom in on with any patch is "what is the user<->kernel interface". Once that is settled, understood and agreed on then we can get into the implementation details. Please do prepare a writeup of that. It could go in [patch 0/n] or into a Documentation/ file.

Quoted 16 lines
include/linux/dynamic_printk.h +2 -2
 	}
 	if (!err)
 		err = length;

@@ -268,8 +338,8 @@ static int pr_debug_seq_show(struct seq_file *s, void *v)
 	rcu_read_lock();
 	head = &module_table[i];
 	hlist_for_each_entry_rcu(element, node, head, hlist)
-		seq_printf(s, "%s %d %d\n", element->name, element->enable,
-				 element->num_uses);
+		seq_printf(s, "%s %d %d %d\n", element->name, element->enable,
+				 element->level, element->num_uses);
 	rcu_read_unlock();
 	return 0;
 }
Signature · 1 line
1.5.4.5