lkml.org 
[lkml]   [2012]   [Nov]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
SubjectRe: [RFC] dynamic_debug: introduce debug_hex_dump()
Date
On Wednesday, November 14, 2012 09:08:52 AM Joe Perches wrote:
> On Wed, 2012-11-14 at 18:18 +0200, Vladimir Kondratiev wrote:
> > And, here it goes (can I call it PATCH?):
> Don't see why not.
>
> > From: Vladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
>
> []
>
> > Introduce debug_hex_dump() that can be dynamically controlled, similar to
> > pr_debug.
> >
> > Also, make print_hex_dump_bytes() dynamically controlled
>
> print_hex_dump_debug might be a better name than
> debug_hex_dump because it's more similar to the other
> print_hex_dump<_foo> names.

Well, let it be:

From 5c9a79ea32e300f9a228d659f325e30d450b57c1 Mon Sep 17 00:00:00 2001
From: Vladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Date: Wed, 14 Nov 2012 19:24:51 +0200
Subject: [PATCH] dynamic_debug: dynamic hex dump

Introduce print_hex_dump_debug() that can be dynamically controlled, similar to
pr_debug.

Also, make print_hex_dump_bytes() dynamically controlled

Implement only 'p' flag (_DPRINTK_FLAGS_PRINT) to keep it simple since hex dump prints
multiple lines and long prefix would impact readability.
To provide line/file etc. information, use pr_debug or similar
before/after print_hex_dump_debug()

Signed-off-by: Vladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
---
Documentation/dynamic-debug-howto.txt | 11 +++++++++--
include/linux/dynamic_debug.h | 10 ++++++++++
include/linux/printk.h | 17 +++++++++++++++++
3 files changed, 36 insertions(+), 2 deletions(-)

diff --git a/Documentation/dynamic-debug-howto.txt b/Documentation/dynamic-debug-howto.txt
index 6e16849..b39a771 100644
--- a/Documentation/dynamic-debug-howto.txt
+++ b/Documentation/dynamic-debug-howto.txt
@@ -6,8 +6,12 @@ This document describes how to use the dynamic debug (dyndbg) feature.

Dynamic debug is designed to allow you to dynamically enable/disable
kernel code to obtain additional kernel information. Currently, if
-CONFIG_DYNAMIC_DEBUG is set, then all pr_debug()/dev_dbg() calls can
-be dynamically enabled per-callsite.
+CONFIG_DYNAMIC_DEBUG is set, then all pr_debug()/dev_dbg() and
+print_hex_dump_debug()/print_hex_dump_bytes() calls can be dynamically
+enabled per-callsite.
+
+If CONFIG_DYNAMIC_DEBUG is not set, print_hex_dump_debug() is just
+shortcut for print_hex_dump(KERN_DEBUG).

Dynamic debug has even more useful features:

@@ -202,6 +206,9 @@ The flags are:
t Include thread ID in messages not generated from interrupt context
_ No flags are set. (Or'd with others on input)

+For print_hex_dump_debug() and print_hex_dump_bytes(), only 'p' flag
+have meaning, other flags ignored.
+
For display, the flags are preceded by '='
(mnemonic: what the flags are currently equal to).

diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h
index 6dd4787..17565ab 100644
--- a/include/linux/dynamic_debug.h
+++ b/include/linux/dynamic_debug.h
@@ -95,6 +95,16 @@ do { \
##__VA_ARGS__); \
} while (0)

+#define dynamic_hex_dump(prefix_str, prefix_type, rowsize, \
+ groupsize, buf, len, ascii) \
+do { \
+ DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, prefix_str); \
+ if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT)) \
+ print_hex_dump(KERN_DEBUG, prefix_str, \
+ prefix_type, rowsize, groupsize, \
+ buf, len, ascii); \
+} while (0)
+
#else

#include <linux/string.h>
diff --git a/include/linux/printk.h b/include/linux/printk.h
index 9afc01e..02c95cf 100644
--- a/include/linux/printk.h
+++ b/include/linux/printk.h
@@ -321,8 +321,13 @@ extern void hex_dump_to_buffer(const void *buf, size_t len,
extern void print_hex_dump(const char *level, const char *prefix_str,
int prefix_type, int rowsize, int groupsize,
const void *buf, size_t len, bool ascii);
+#if defined(CONFIG_DYNAMIC_DEBUG)
+#define print_hex_dump_bytes(prefix_str, prefix_type, buf, len) \
+ dynamic_hex_dump(prefix_str, prefix_type, 16, 1, buf, len, true)
+#else
extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
const void *buf, size_t len);
+#endif /* defined(CONFIG_DYNAMIC_DEBUG) */
#else
static inline void print_hex_dump(const char *level, const char *prefix_str,
int prefix_type, int rowsize, int groupsize,
@@ -336,4 +341,16 @@ static inline void print_hex_dump_bytes(const char *prefix_str, int prefix_type,

#endif

+#if defined(CONFIG_DYNAMIC_DEBUG)
+#define print_hex_dump_debug(prefix_str, prefix_type, rowsize, \
+ groupsize, buf, len, ascii) \
+ dynamic_hex_dump(prefix_str, prefix_type, rowsize, \
+ groupsize, buf, len, ascii)
+#else
+#define print_hex_dump_debug(prefix_str, prefix_type, rowsize, \
+ groupsize, buf, len, ascii) \
+ print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, rowsize, \
+ groupsize, buf, len, ascii)
+#endif /* defined(CONFIG_DYNAMIC_DEBUG) */
+
#endif
--
1.7.10.4



\
 
 \ /
  Last update: 2012-11-14 19:01    [W:0.085 / U:0.108 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site