lkml.org 
[lkml]   [2011]   [Jan]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH] Dynamic debug: Add more flags
    Date
    Add flags that allow the user to specify via debugfs whether or not the
    module name, function name, line number and/or thread ID have to be
    included in the printed message.

    Signed-off-by: Bart Van Assche <bvanassche@acm.org>
    Cc: Greg Banks <gnb@sgi.com>
    Cc: Jason Baron <jbaron@redhat.com>
    Cc: Greg Kroah-Hartman <gregkh@suse.de>
    Cc: Konrad Rzeszutek Wilk <konrad@darnok.org>
    ---
    Documentation/dynamic-debug-howto.txt | 12 +++++-
    include/linux/dynamic_debug.h | 8 ++++-
    lib/dynamic_debug.c | 60 ++++++++++++++++++++++++++++-----
    3 files changed, 68 insertions(+), 12 deletions(-)

    diff --git a/Documentation/dynamic-debug-howto.txt b/Documentation/dynamic-debug-howto.txt
    index 58ea64a..e6c4b75 100644
    --- a/Documentation/dynamic-debug-howto.txt
    +++ b/Documentation/dynamic-debug-howto.txt
    @@ -205,12 +205,20 @@ of the characters:

    The flags are:

    +f
    + Include the function name in the printed message
    +l
    + Include line number in the printed message
    +m
    + Include module name in the printed message
    p
    Causes a printk() message to be emitted to dmesg
    +t
    + Include thread ID in messages not generated from interrupt context

    -Note the regexp ^[-+=][scp]+$ matches a flags specification.
    +Note the regexp ^[-+=][flmpt]+$ matches a flags specification.
    Note also that there is no convenient syntax to remove all
    -the flags at once, you need to use "-psc".
    +the flags at once, you need to use "-flmpt".


    Debug messages during boot process
    diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h
    index 1c70028..0c9653f 100644
    --- a/include/linux/dynamic_debug.h
    +++ b/include/linux/dynamic_debug.h
    @@ -31,6 +31,10 @@ struct _ddebug {
    * writes commands to <debugfs>/dynamic_debug/control
    */
    #define _DPRINTK_FLAGS_PRINT (1<<0) /* printk() a message using the format */
    +#define _DPRINTK_FLAGS_INCL_MODNAME (1<<1)
    +#define _DPRINTK_FLAGS_INCL_FUNCNAME (1<<2)
    +#define _DPRINTK_FLAGS_INCL_LINENO (1<<3)
    +#define _DPRINTK_FLAGS_INCL_TID (1<<4)
    #define _DPRINTK_FLAGS_DEFAULT 0
    unsigned int flags:8;
    char enabled;
    @@ -42,6 +46,8 @@ int ddebug_add_module(struct _ddebug *tab, unsigned int n,

    #if defined(CONFIG_DYNAMIC_DEBUG)
    extern int ddebug_remove_module(const char *mod_name);
    +extern int __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...)
    + __attribute__ ((format (printf, 2, 3)));

    #define dynamic_pr_debug(fmt, ...) do { \
    static struct _ddebug descriptor \
    @@ -50,7 +56,7 @@ extern int ddebug_remove_module(const char *mod_name);
    { KBUILD_MODNAME, __func__, __FILE__, fmt, __LINE__, \
    _DPRINTK_FLAGS_DEFAULT }; \
    if (unlikely(descriptor.enabled)) \
    - printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); \
    + __dynamic_pr_debug(&descriptor, pr_fmt(fmt), ##__VA_ARGS__); \
    } while (0)


    diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
    index b335acb..863c834 100644
    --- a/lib/dynamic_debug.c
    +++ b/lib/dynamic_debug.c
    @@ -7,6 +7,7 @@
    * Copyright (C) 2008 Jason Baron <jbaron@redhat.com>
    * By Greg Banks <gnb@melbourne.sgi.com>
    * Copyright (c) 2008 Silicon Graphics Inc. All Rights Reserved.
    + * Copyright (C) 2011 Bart Van Assche. All Rights Reserved.
    */

    #include <linux/kernel.h>
    @@ -27,6 +28,7 @@
    #include <linux/debugfs.h>
    #include <linux/slab.h>
    #include <linux/jump_label.h>
    +#include <linux/hardirq.h>

    extern struct _ddebug __start___verbose[];
    extern struct _ddebug __stop___verbose[];
    @@ -63,15 +65,25 @@ static inline const char *basename(const char *path)
    return tail ? tail+1 : path;
    }

    +static struct { unsigned flag:8; char opt_char; } opt_array[] = {
    + { _DPRINTK_FLAGS_PRINT, 'p' },
    + { _DPRINTK_FLAGS_INCL_MODNAME, 'm' },
    + { _DPRINTK_FLAGS_INCL_FUNCNAME, 'f' },
    + { _DPRINTK_FLAGS_INCL_LINENO, 'l' },
    + { _DPRINTK_FLAGS_INCL_TID, 't' },
    +};
    +
    /* format a string into buf[] which describes the _ddebug's flags */
    static char *ddebug_describe_flags(struct _ddebug *dp, char *buf,
    size_t maxlen)
    {
    char *p = buf;
    + int i;

    BUG_ON(maxlen < 4);
    - if (dp->flags & _DPRINTK_FLAGS_PRINT)
    - *p++ = 'p';
    + for (i = 0; i < ARRAY_SIZE(opt_array); ++i)
    + if (dp->flags & opt_array[i].flag)
    + *p++ = opt_array[i].opt_char;
    if (p == buf)
    *p++ = '-';
    *p = '\0';
    @@ -343,7 +355,7 @@ static int ddebug_parse_flags(const char *str, unsigned int *flagsp,
    unsigned int *maskp)
    {
    unsigned flags = 0;
    - int op = '=';
    + int op = '=', i;

    switch (*str) {
    case '+':
    @@ -358,13 +370,14 @@ static int ddebug_parse_flags(const char *str, unsigned int *flagsp,
    printk(KERN_INFO "%s: op='%c'\n", __func__, op);

    for ( ; *str ; ++str) {
    - switch (*str) {
    - case 'p':
    - flags |= _DPRINTK_FLAGS_PRINT;
    - break;
    - default:
    - return -EINVAL;
    + for (i = ARRAY_SIZE(opt_array) - 1; i >= 0; i--) {
    + if (*str == opt_array[i].opt_char) {
    + flags |= opt_array[i].flag;
    + break;
    + }
    }
    + if (i < 0)
    + return -EINVAL;
    }
    if (flags == 0)
    return -EINVAL;
    @@ -413,6 +426,35 @@ static int ddebug_exec_query(char *query_string)
    return 0;
    }

    +int __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...)
    +{
    + va_list args;
    + int res;
    +
    + BUG_ON(!descriptor);
    + BUG_ON(!fmt);
    +
    + va_start(args, fmt);
    + res = printk(KERN_DEBUG);
    + if (descriptor->flags & _DPRINTK_FLAGS_INCL_TID) {
    + if (in_interrupt())
    + res += printk(KERN_CONT "<intr> ");
    + else
    + res += printk(KERN_CONT "[%d] ", task_pid_vnr(current));
    + }
    + if (descriptor->flags & _DPRINTK_FLAGS_INCL_MODNAME)
    + res += printk(KERN_CONT "%s:", descriptor->modname);
    + if (descriptor->flags & _DPRINTK_FLAGS_INCL_FUNCNAME)
    + res += printk(KERN_CONT "%s:", descriptor->function);
    + if (descriptor->flags & _DPRINTK_FLAGS_INCL_LINENO)
    + res += printk(KERN_CONT "%d ", descriptor->lineno);
    + res += vprintk(fmt, args);
    + va_end(args);
    +
    + return res;
    +}
    +EXPORT_SYMBOL(__dynamic_pr_debug);
    +
    static __initdata char ddebug_setup_string[1024];
    static __init int ddebug_setup_query(char *str)
    {
    --
    1.7.1


    \
     
     \ /
      Last update: 2011-01-23 17:19    [W:0.029 / U:0.504 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site