Return-path: Received: from sabertooth01.qualcomm.com ([65.197.215.72]:22086 "EHLO sabertooth01.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964804Ab2KNQSU (ORCPT ); Wed, 14 Nov 2012 11:18:20 -0500 From: Vladimir Kondratiev To: Joe Perches CC: "John W . Linville" , Johannes Berg , Andrew Morton , , "Luis R . Rodriguez" , Jason Baron , Jim Cromie , Greg KH , LKML Subject: Re: [RFC] dynamic_debug: introduce debug_hex_dump() Date: Wed, 14 Nov 2012 18:18:16 +0200 Message-ID: <4818336.JicdpLVKSo@lx-vladimir> (sfid-20121114_171838_125998_1C41D263) In-Reply-To: <1352900468.9388.20.camel@joe-AO722> References: <1352895463-22851-1-git-send-email-qca_vkondrat@qca.qualcomm.com> <1352895463-22851-2-git-send-email-qca_vkondrat@qca.qualcomm.com> <1352900468.9388.20.camel@joe-AO722> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: linux-wireless-owner@vger.kernel.org List-ID: On Wednesday, November 14, 2012 05:41:08 AM Joe Perches wrote: > On Wed, 2012-11-14 at 14:17 +0200, Vladimir Kondratiev wrote: > > Introduce debug_hex_dump() that can be dynamically controlled, similar to > > pr_debug. > > (added Jason Baron, Jim Cromie, GregKH and lkml to cc's) > > [] > > > diff --git a/include/linux/printk.h b/include/linux/printk.h > > [] > > > @@ -220,6 +220,20 @@ extern void dump_stack(void) __cold; > > > > no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) > > > > #endifD > > > > +#if defined(CONFIG_DYNAMIC_DEBUG) > > +#define debug_hex_dump(prefix_str, prefix_type, rowsize, \ > > + groupsize, buf, len, ascii) \ > > + dynamic_hex_dump(prefix_str, prefix_type,\ > > + rowsize, groupsize, buf,\ > > + len, ascii) > > +#else > > +#define debug_hex_dump(prefix_str, prefix_type, rowsize, \ > > + groupsize, buf, len, ascii) \ > > + print_hex_dump(KERN_DEBUG, prefix_str, \ > > + prefix_type, rowsize, \ > > + groupsize, buf, len, ascii) > > +#endif > > These should be in a different location after print_hex_dump > is declared. Also for #defines, the indentation doesn't > need to be so deep. Ups, correct. > > #if defined(CONFIG_DYNAMIC_DEBUG) > #define debug_hex_dump(prefix_str, prefix_type, rowsize, \ > groupsize, buf, len, ascii) \ > dynamic_hex_dump(prefix_str, prefix_type, \ > rowsize, groupsize, buf, len, ascii) > #else > #define debug_hex_dump(prefix_str, prefix_type, rowsize, \ > groupsize, buf, len, ascii) \ > print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, \ > rowsize, groupsize, buf, len, ascii) > #endif > > A better option might be to convert print_hex_dump_bytes() > to dynamic_debug as that's already KERN_DEBUG. That > could be simpler overall and it makes existing calls > become dynamic as well. And, here it goes (can I call it PATCH?): >From 755b74861b66435bfe4875b64a53c45bbe172495 Mon Sep 17 00:00:00 2001 From: Vladimir Kondratiev Date: Wed, 14 Nov 2012 18:14:15 +0200 Subject: [PATCH] dynamic_debug: dynamic hex dump Introduce debug_hex_dump() 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 debug_hex_dump() Signed-off-by: Vladimir Kondratiev --- 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..cec98f8 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 +debug_hex_dump()/print_hex_dump_bytes() calls can be dynamically +enabled per-callsite. + +If CONFIG_DYNAMIC_DEBUG is not set, debug_hex_dump() 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 debug_hex_dump() 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 diff --git a/include/linux/printk.h b/include/linux/printk.h index 9afc01e..82dc610 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 debug_hex_dump(prefix_str, prefix_type, rowsize, \ + groupsize, buf, len, ascii) \ + dynamic_hex_dump(prefix_str, prefix_type, rowsize, \ + groupsize, buf, len, ascii) +#else +#define debug_hex_dump(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