Eric Lee / linux-smarc-t335x-v3.2

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Commit e9d376f0fa66bd630fe27403669c6ae6c22a868f

Authored by Jason Baron
Committed by Greg Kroah-Hartman
1 parent 095160aee9
Exists in master and in 4 other branches v3.2_AM335xPSP_04.06.00.11, v3.2_NEWT335xPSP_04.06.00.11, v3.2_SBC_SMARTMEN, v3.2_SMARCT335xPSP_04.06.00.11

dynamic debug: combine dprintk and dynamic printk 

This patch combines Greg Bank's dprintk() work with the existing dynamic
printk patchset, we are now calling it 'dynamic debug'.

The new feature of this patchset is a richer /debugfs control file interface,
(an example output from my system is at the bottom), which allows fined grained
control over the the debug output. The output can be controlled by function,
file, module, format string, and line number.

for example, enabled all debug messages in module 'nf_conntrack':

echo -n 'module nf_conntrack +p' > /mnt/debugfs/dynamic_debug/control

to disable them:

echo -n 'module nf_conntrack -p' > /mnt/debugfs/dynamic_debug/control

A further explanation can be found in the documentation patch.

Signed-off-by: Greg Banks <gnb@sgi.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Showing 13 changed files with 867 additions and 543 deletions Side-by-side Diff

Documentation/kernel-parameters.txt
Diff comments   View file @ e9d376f
... ... @@ -1816,11 +1816,6 @@
1816 1816 autoconfiguration.
1817 1817 Ranges are in pairs (memory base and size).
1818 1818  
1819   - dynamic_printk Enables pr_debug()/dev_dbg() calls if
1820   - CONFIG_DYNAMIC_PRINTK_DEBUG has been enabled.
1821   - These can also be switched on/off via
1822   - <debugfs>/dynamic_printk/modules
1823   -
1824 1819 print-fatal-signals=
1825 1820 [KNL] debug: print fatal signals
1826 1821 print-fatal-signals=1: print segfault info to
include/asm-generic/vmlinux.lds.h
Diff comments   View file @ e9d376f
... ... @@ -80,6 +80,11 @@
80 80 VMLINUX_SYMBOL(__start___tracepoints) = .; \
81 81 *(__tracepoints) \
82 82 VMLINUX_SYMBOL(__stop___tracepoints) = .; \
  83 + /* implement dynamic printk debug */ \
  84 + . = ALIGN(8); \
  85 + VMLINUX_SYMBOL(__start___verbose) = .; \
  86 + *(__verbose) \
  87 + VMLINUX_SYMBOL(__stop___verbose) = .; \
83 88 LIKELY_PROFILE() \
84 89 BRANCH_PROFILE()
85 90  
... ... @@ -309,15 +314,7 @@
309 314 CPU_DISCARD(init.data) \
310 315 CPU_DISCARD(init.rodata) \
311 316 MEM_DISCARD(init.data) \
312   - MEM_DISCARD(init.rodata) \
313   - /* implement dynamic printk debug */ \
314   - VMLINUX_SYMBOL(__start___verbose_strings) = .; \
315   - *(__verbose_strings) \
316   - VMLINUX_SYMBOL(__stop___verbose_strings) = .; \
317   - . = ALIGN(8); \
318   - VMLINUX_SYMBOL(__start___verbose) = .; \
319   - *(__verbose) \
320   - VMLINUX_SYMBOL(__stop___verbose) = .;
  317 + MEM_DISCARD(init.rodata)
321 318  
322 319 #define INIT_TEXT \
323 320 *(.init.text) \
include/linux/device.h
Diff comments   View file @ e9d376f
... ... @@ -582,7 +582,7 @@
582 582 #if defined(DEBUG)
583 583 #define dev_dbg(dev, format, arg...) \
584 584 dev_printk(KERN_DEBUG , dev , format , ## arg)
585   -#elif defined(CONFIG_DYNAMIC_PRINTK_DEBUG)
  585 +#elif defined(CONFIG_DYNAMIC_DEBUG)
586 586 #define dev_dbg(dev, format, ...) do { \
587 587 dynamic_dev_dbg(dev, format, ##__VA_ARGS__); \
588 588 } while (0)
include/linux/dynamic_debug.h
Diff comments   View file @ e9d376f
  1 +#ifndef _DYNAMIC_DEBUG_H
  2 +#define _DYNAMIC_DEBUG_H
  3 +
  4 +/* dynamic_printk_enabled, and dynamic_printk_enabled2 are bitmasks in which
  5 + * bit n is set to 1 if any modname hashes into the bucket n, 0 otherwise. They
  6 + * use independent hash functions, to reduce the chance of false positives.
  7 + */
  8 +extern long long dynamic_debug_enabled;
  9 +extern long long dynamic_debug_enabled2;
  10 +
  11 +/*
  12 + * An instance of this structure is created in a special
  13 + * ELF section at every dynamic debug callsite. At runtime,
  14 + * the special section is treated as an array of these.
  15 + */
  16 +struct _ddebug {
  17 + /*
  18 + * These fields are used to drive the user interface
  19 + * for selecting and displaying debug callsites.
  20 + */
  21 + const char *modname;
  22 + const char *function;
  23 + const char *filename;
  24 + const char *format;
  25 + char primary_hash;
  26 + char secondary_hash;
  27 + unsigned int lineno:24;
  28 + /*
  29 + * The flags field controls the behaviour at the callsite.
  30 + * The bits here are changed dynamically when the user
  31 + * writes commands to <debugfs>/dynamic_debug/ddebug
  32 + */
  33 +#define _DPRINTK_FLAGS_PRINT (1<<0) /* printk() a message using the format */
  34 +#define _DPRINTK_FLAGS_DEFAULT 0
  35 + unsigned int flags:8;
  36 +} __attribute__((aligned(8)));
  37 +
  38 +
  39 +int ddebug_add_module(struct _ddebug *tab, unsigned int n,
  40 + const char *modname);
  41 +
  42 +#if defined(CONFIG_DYNAMIC_DEBUG)
  43 +extern int ddebug_remove_module(char *mod_name);
  44 +
  45 +#define __dynamic_dbg_enabled(dd) ({ \
  46 + int __ret = 0; \
  47 + if (unlikely((dynamic_debug_enabled & (1LL << DEBUG_HASH)) && \
  48 + (dynamic_debug_enabled2 & (1LL << DEBUG_HASH2)))) \
  49 + if (unlikely(dd.flags)) \
  50 + __ret = 1; \
  51 + __ret; })
  52 +
  53 +#define dynamic_pr_debug(fmt, ...) do { \
  54 + static struct _ddebug descriptor \
  55 + __used \
  56 + __attribute__((section("__verbose"), aligned(8))) = \
  57 + { KBUILD_MODNAME, __func__, __FILE__, fmt, DEBUG_HASH, \
  58 + DEBUG_HASH2, __LINE__, _DPRINTK_FLAGS_DEFAULT }; \
  59 + if (__dynamic_dbg_enabled(descriptor)) \
  60 + printk(KERN_DEBUG KBUILD_MODNAME ":" fmt, \
  61 + ##__VA_ARGS__); \
  62 + } while (0)
  63 +
  64 +
  65 +#define dynamic_dev_dbg(dev, fmt, ...) do { \
  66 + static struct _ddebug descriptor \
  67 + __used \
  68 + __attribute__((section("__verbose"), aligned(8))) = \
  69 + { KBUILD_MODNAME, __func__, __FILE__, fmt, DEBUG_HASH, \
  70 + DEBUG_HASH2, __LINE__, _DPRINTK_FLAGS_DEFAULT }; \
  71 + if (__dynamic_dbg_enabled(descriptor)) \
  72 + dev_printk(KERN_DEBUG, dev, \
  73 + KBUILD_MODNAME ": " fmt, \
  74 + ##__VA_ARGS__); \
  75 + } while (0)
  76 +
  77 +#else
  78 +
  79 +static inline int ddebug_remove_module(char *mod)
  80 +{
  81 + return 0;
  82 +}
  83 +
  84 +#define dynamic_pr_debug(fmt, ...) do { } while (0)
  85 +#define dynamic_dev_dbg(dev, format, ...) do { } while (0)
  86 +#endif
  87 +
  88 +#endif
include/linux/dynamic_printk.h
View file @ e9d376f
1   -#ifndef _DYNAMIC_PRINTK_H
2   -#define _DYNAMIC_PRINTK_H
3   -
4   -#define DYNAMIC_DEBUG_HASH_BITS 6
5   -#define DEBUG_HASH_TABLE_SIZE (1 << DYNAMIC_DEBUG_HASH_BITS)
6   -
7   -#define TYPE_BOOLEAN 1
8   -
9   -#define DYNAMIC_ENABLED_ALL 0
10   -#define DYNAMIC_ENABLED_NONE 1
11   -#define DYNAMIC_ENABLED_SOME 2
12   -
13   -extern int dynamic_enabled;
14   -
15   -/* dynamic_printk_enabled, and dynamic_printk_enabled2 are bitmasks in which
16   - * bit n is set to 1 if any modname hashes into the bucket n, 0 otherwise. They
17   - * use independent hash functions, to reduce the chance of false positives.
18   - */
19   -extern long long dynamic_printk_enabled;
20   -extern long long dynamic_printk_enabled2;
21   -
22   -struct mod_debug {
23   - char *modname;
24   - char *logical_modname;
25   - char *flag_names;
26   - int type;
27   - int hash;
28   - int hash2;
29   -} __attribute__((aligned(8)));
30   -
31   -int register_dynamic_debug_module(char *mod_name, int type, char *share_name,
32   - char *flags, int hash, int hash2);
33   -
34   -#if defined(CONFIG_DYNAMIC_PRINTK_DEBUG)
35   -extern int unregister_dynamic_debug_module(char *mod_name);
36   -extern int __dynamic_dbg_enabled_helper(char *modname, int type,
37   - int value, int hash);
38   -
39   -#define __dynamic_dbg_enabled(module, type, value, level, hash) ({ \
40   - int __ret = 0; \
41   - if (unlikely((dynamic_printk_enabled & (1LL << DEBUG_HASH)) && \
42   - (dynamic_printk_enabled2 & (1LL << DEBUG_HASH2)))) \
43   - __ret = __dynamic_dbg_enabled_helper(module, type, \
44   - value, hash);\
45   - __ret; })
46   -
47   -#define dynamic_pr_debug(fmt, ...) do { \
48   - static char mod_name[] \
49   - __attribute__((section("__verbose_strings"))) \
50   - = KBUILD_MODNAME; \
51   - static struct mod_debug descriptor \
52   - __used \
53   - __attribute__((section("__verbose"), aligned(8))) = \
54   - { mod_name, mod_name, NULL, TYPE_BOOLEAN, DEBUG_HASH, DEBUG_HASH2 };\
55   - if (__dynamic_dbg_enabled(KBUILD_MODNAME, TYPE_BOOLEAN, \
56   - 0, 0, DEBUG_HASH)) \
57   - printk(KERN_DEBUG KBUILD_MODNAME ":" fmt, \
58   - ##__VA_ARGS__); \
59   - } while (0)
60   -
61   -#define dynamic_dev_dbg(dev, format, ...) do { \
62   - static char mod_name[] \
63   - __attribute__((section("__verbose_strings"))) \
64   - = KBUILD_MODNAME; \
65   - static struct mod_debug descriptor \
66   - __used \
67   - __attribute__((section("__verbose"), aligned(8))) = \
68   - { mod_name, mod_name, NULL, TYPE_BOOLEAN, DEBUG_HASH, DEBUG_HASH2 };\
69   - if (__dynamic_dbg_enabled(KBUILD_MODNAME, TYPE_BOOLEAN, \
70   - 0, 0, DEBUG_HASH)) \
71   - dev_printk(KERN_DEBUG, dev, \
72   - KBUILD_MODNAME ": " format, \
73   - ##__VA_ARGS__); \
74   - } while (0)
75   -
76   -#else
77   -
78   -static inline int unregister_dynamic_debug_module(const char *mod_name)
79   -{
80   - return 0;
81   -}
82   -static inline int __dynamic_dbg_enabled_helper(char *modname, int type,
83   - int value, int hash)
84   -{
85   - return 0;
86   -}
87   -
88   -#define __dynamic_dbg_enabled(module, type, value, level, hash) ({ 0; })
89   -#define dynamic_pr_debug(fmt, ...) do { } while (0)
90   -#define dynamic_dev_dbg(dev, format, ...) do { } while (0)
91   -#endif
92   -
93   -#endif
include/linux/kernel.h
Diff comments   View file @ e9d376f
... ... @@ -16,7 +16,7 @@
16 16 #include <linux/log2.h>
17 17 #include <linux/typecheck.h>
18 18 #include <linux/ratelimit.h>
19   -#include <linux/dynamic_printk.h>
  19 +#include <linux/dynamic_debug.h>
20 20 #include <asm/byteorder.h>
21 21 #include <asm/bug.h>
22 22  
... ... @@ -358,7 +358,7 @@
358 358 #if defined(DEBUG)
359 359 #define pr_debug(fmt, ...) \
360 360 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
361   -#elif defined(CONFIG_DYNAMIC_PRINTK_DEBUG)
  361 +#elif defined(CONFIG_DYNAMIC_DEBUG)
362 362 #define pr_debug(fmt, ...) do { \
363 363 dynamic_pr_debug(pr_fmt(fmt), ##__VA_ARGS__); \
364 364 } while (0)
... ... @@ -822,7 +822,7 @@
822 822 mutex_lock(&module_mutex);
823 823 /* Store the name of the last unloaded module for diagnostic purposes */
824 824 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
825   - unregister_dynamic_debug_module(mod->name);
  825 + ddebug_remove_module(mod->name);
826 826 free_module(mod);
827 827  
828 828 out:
829 829  
... ... @@ -1827,19 +1827,13 @@
1827 1827 }
1828 1828 #endif /* CONFIG_KALLSYMS */
1829 1829  
1830   -static void dynamic_printk_setup(struct mod_debug *debug, unsigned int num)
  1830 +static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
1831 1831 {
1832   -#ifdef CONFIG_DYNAMIC_PRINTK_DEBUG
1833   - unsigned int i;
1834   -
1835   - for (i = 0; i < num; i++) {
1836   - register_dynamic_debug_module(debug[i].modname,
1837   - debug[i].type,
1838   - debug[i].logical_modname,
1839   - debug[i].flag_names,
1840   - debug[i].hash, debug[i].hash2);
1841   - }
1842   -#endif /* CONFIG_DYNAMIC_PRINTK_DEBUG */
  1832 +#ifdef CONFIG_DYNAMIC_DEBUG
  1833 + if (ddebug_add_module(debug, num, debug->modname))
  1834 + printk(KERN_ERR "dynamic debug error adding module: %s\n",
  1835 + debug->modname);
  1836 +#endif
1843 1837 }
1844 1838  
1845 1839 static void *module_alloc_update_bounds(unsigned long size)
1846 1840  
... ... @@ -2213,12 +2207,13 @@
2213 2207 add_kallsyms(mod, sechdrs, symindex, strindex, secstrings);
2214 2208  
2215 2209 if (!mod->taints) {
2216   - struct mod_debug *debug;
  2210 + struct _ddebug *debug;
2217 2211 unsigned int num_debug;
2218 2212  
2219 2213 debug = section_objs(hdr, sechdrs, secstrings, "__verbose",
2220 2214 sizeof(*debug), &num_debug);
2221   - dynamic_printk_setup(debug, num_debug);
  2215 + if (debug)
  2216 + dynamic_debug_setup(debug, num_debug);
2222 2217 }
2223 2218  
2224 2219 /* sechdrs[0].sh_size is always zero */
... ... @@ -847,7 +847,7 @@
847 847  
848 848 Say N if you are unsure.
849 849  
850   -config DYNAMIC_PRINTK_DEBUG
  850 +config DYNAMIC_DEBUG
851 851 bool "Enable dynamic printk() call support"
852 852 default n
853 853 depends on PRINTK
... ... @@ -82,7 +82,7 @@
82 82  
83 83 obj-$(CONFIG_HAVE_ARCH_TRACEHOOK) += syscall.o
84 84  
85   -obj-$(CONFIG_DYNAMIC_PRINTK_DEBUG) += dynamic_printk.o
  85 +obj-$(CONFIG_DYNAMIC_DEBUG) += dynamic_debug.o
86 86  
87 87 hostprogs-y := gen_crc32table
88 88 clean-files := crc32table.h
  1 +/*
  2 + * lib/dynamic_debug.c
  3 + *
  4 + * make pr_debug()/dev_dbg() calls runtime configurable based upon their
  5 + * source module.
  6 + *
  7 + * Copyright (C) 2008 Jason Baron <jbaron@redhat.com>
  8 + * By Greg Banks <gnb@melbourne.sgi.com>
  9 + * Copyright (c) 2008 Silicon Graphics Inc. All Rights Reserved.
  10 + */
  11 +
  12 +#include <linux/kernel.h>
  13 +#include <linux/module.h>
  14 +#include <linux/moduleparam.h>
  15 +#include <linux/kallsyms.h>
  16 +#include <linux/version.h>
  17 +#include <linux/types.h>
  18 +#include <linux/mutex.h>
  19 +#include <linux/proc_fs.h>
  20 +#include <linux/seq_file.h>
  21 +#include <linux/list.h>
  22 +#include <linux/sysctl.h>
  23 +#include <linux/ctype.h>
  24 +#include <linux/uaccess.h>
  25 +#include <linux/dynamic_debug.h>
  26 +#include <linux/debugfs.h>
  27 +
  28 +extern struct _ddebug __start___verbose[];
  29 +extern struct _ddebug __stop___verbose[];
  30 +
  31 +/* dynamic_debug_enabled, and dynamic_debug_enabled2 are bitmasks in which
  32 + * bit n is set to 1 if any modname hashes into the bucket n, 0 otherwise. They
  33 + * use independent hash functions, to reduce the chance of false positives.
  34 + */
  35 +long long dynamic_debug_enabled;
  36 +EXPORT_SYMBOL_GPL(dynamic_debug_enabled);
  37 +long long dynamic_debug_enabled2;
  38 +EXPORT_SYMBOL_GPL(dynamic_debug_enabled2);
  39 +
  40 +struct ddebug_table {
  41 + struct list_head link;
  42 + char *mod_name;
  43 + unsigned int num_ddebugs;
  44 + unsigned int num_enabled;
  45 + struct _ddebug *ddebugs;
  46 +};
  47 +
  48 +struct ddebug_query {
  49 + const char *filename;
  50 + const char *module;
  51 + const char *function;
  52 + const char *format;
  53 + unsigned int first_lineno, last_lineno;
  54 +};
  55 +
  56 +struct ddebug_iter {
  57 + struct ddebug_table *table;
  58 + unsigned int idx;
  59 +};
  60 +
  61 +static DEFINE_MUTEX(ddebug_lock);
  62 +static LIST_HEAD(ddebug_tables);
  63 +static int verbose = 0;
  64 +
  65 +/* Return the last part of a pathname */
  66 +static inline const char *basename(const char *path)
  67 +{
  68 + const char *tail = strrchr(path, '/');
  69 + return tail ? tail+1 : path;
  70 +}
  71 +
  72 +/* format a string into buf[] which describes the _ddebug's flags */
  73 +static char *ddebug_describe_flags(struct _ddebug *dp, char *buf,
  74 + size_t maxlen)
  75 +{
  76 + char *p = buf;
  77 +
  78 + BUG_ON(maxlen < 4);
  79 + if (dp->flags & _DPRINTK_FLAGS_PRINT)
  80 + *p++ = 'p';
  81 + if (p == buf)
  82 + *p++ = '-';
  83 + *p = '\0';
  84 +
  85 + return buf;
  86 +}
  87 +
  88 +/*
  89 + * must be called with ddebug_lock held
  90 + */
  91 +
  92 +static int disabled_hash(char hash, bool first_table)
  93 +{
  94 + struct ddebug_table *dt;
  95 + char table_hash_value;
  96 +
  97 + list_for_each_entry(dt, &ddebug_tables, link) {
  98 + if (first_table)
  99 + table_hash_value = dt->ddebugs->primary_hash;
  100 + else
  101 + table_hash_value = dt->ddebugs->secondary_hash;
  102 + if (dt->num_enabled && (hash == table_hash_value))
  103 + return 0;
  104 + }
  105 + return 1;
  106 +}
  107 +
  108 +/*
  109 + * Search the tables for _ddebug's which match the given
  110 + * `query' and apply the `flags' and `mask' to them. Tells
  111 + * the user which ddebug's were changed, or whether none
  112 + * were matched.
  113 + */
  114 +static void ddebug_change(const struct ddebug_query *query,
  115 + unsigned int flags, unsigned int mask)
  116 +{
  117 + int i;
  118 + struct ddebug_table *dt;
  119 + unsigned int newflags;
  120 + unsigned int nfound = 0;
  121 + char flagbuf[8];
  122 +
  123 + /* search for matching ddebugs */
  124 + mutex_lock(&ddebug_lock);
  125 + list_for_each_entry(dt, &ddebug_tables, link) {
  126 +
  127 + /* match against the module name */
  128 + if (query->module != NULL &&
  129 + strcmp(query->module, dt->mod_name))
  130 + continue;
  131 +
  132 + for (i = 0 ; i < dt->num_ddebugs ; i++) {
  133 + struct _ddebug *dp = &dt->ddebugs[i];
  134 +
  135 + /* match against the source filename */
  136 + if (query->filename != NULL &&
  137 + strcmp(query->filename, dp->filename) &&
  138 + strcmp(query->filename, basename(dp->filename)))
  139 + continue;
  140 +
  141 + /* match against the function */
  142 + if (query->function != NULL &&
  143 + strcmp(query->function, dp->function))
  144 + continue;
  145 +
  146 + /* match against the format */
  147 + if (query->format != NULL &&
  148 + strstr(dp->format, query->format) == NULL)
  149 + continue;
  150 +
  151 + /* match against the line number range */
  152 + if (query->first_lineno &&
  153 + dp->lineno < query->first_lineno)
  154 + continue;
  155 + if (query->last_lineno &&
  156 + dp->lineno > query->last_lineno)
  157 + continue;
  158 +
  159 + nfound++;
  160 +
  161 + newflags = (dp->flags & mask) | flags;
  162 + if (newflags == dp->flags)
  163 + continue;
  164 +
  165 + if (!newflags)
  166 + dt->num_enabled--;
  167 + else if (!dp-flags)
  168 + dt->num_enabled++;
  169 + dp->flags = newflags;
  170 + if (newflags) {
  171 + dynamic_debug_enabled |=
  172 + (1LL << dp->primary_hash);
  173 + dynamic_debug_enabled2 |=
  174 + (1LL << dp->secondary_hash);
  175 + } else {
  176 + if (disabled_hash(dp->primary_hash, true))
  177 + dynamic_debug_enabled &=
  178 + ~(1LL << dp->primary_hash);
  179 + if (disabled_hash(dp->secondary_hash, false))
  180 + dynamic_debug_enabled2 &=
  181 + ~(1LL << dp->secondary_hash);
  182 + }
  183 + if (verbose)
  184 + printk(KERN_INFO
  185 + "ddebug: changed %s:%d [%s]%s %s\n",
  186 + dp->filename, dp->lineno,
  187 + dt->mod_name, dp->function,
  188 + ddebug_describe_flags(dp, flagbuf,
  189 + sizeof(flagbuf)));
  190 + }
  191 + }
  192 + mutex_unlock(&ddebug_lock);
  193 +
  194 + if (!nfound && verbose)
  195 + printk(KERN_INFO "ddebug: no matches for query\n");
  196 +}
  197 +
  198 +/*
  199 + * Wrapper around strsep() to collapse the multiple empty tokens
  200 + * that it returns when fed sequences of separator characters.
  201 + * Now, if we had strtok_r()...
  202 + */
  203 +static inline char *nearly_strtok_r(char **p, const char *sep)
  204 +{
  205 + char *r;
  206 +
  207 + while ((r = strsep(p, sep)) != NULL && *r == '\0')
  208 + ;
  209 + return r;
  210 +}
  211 +
  212 +/*
  213 + * Split the buffer `buf' into space-separated words.
  214 + * Return the number of such words or <0 on error.
  215 + */
  216 +static int ddebug_tokenize(char *buf, char *words[], int maxwords)
  217 +{
  218 + int nwords = 0;
  219 +
  220 + while (nwords < maxwords &&
  221 + (words[nwords] = nearly_strtok_r(&buf, " \t\r\n")) != NULL)
  222 + nwords++;
  223 + if (buf)
  224 + return -EINVAL; /* ran out of words[] before bytes */
  225 +
  226 + if (verbose) {
  227 + int i;
  228 + printk(KERN_INFO "%s: split into words:", __func__);
  229 + for (i = 0 ; i < nwords ; i++)
  230 + printk(" \"%s\"", words[i]);
  231 + printk("\n");
  232 + }
  233 +
  234 + return nwords;
  235 +}
  236 +
  237 +/*
  238 + * Parse a single line number. Note that the empty string ""
  239 + * is treated as a special case and converted to zero, which
  240 + * is later treated as a "don't care" value.
  241 + */
  242 +static inline int parse_lineno(const char *str, unsigned int *val)
  243 +{
  244 + char *end = NULL;
  245 + BUG_ON(str == NULL);
  246 + if (*str == '\0') {
  247 + *val = 0;
  248 + return 0;
  249 + }
  250 + *val = simple_strtoul(str, &end, 10);
  251 + return end == NULL || end == str || *end != '\0' ? -EINVAL : 0;
  252 +}
  253 +
  254 +/*
  255 + * Undo octal escaping in a string, inplace. This is useful to
  256 + * allow the user to express a query which matches a format
  257 + * containing embedded spaces.
  258 + */
  259 +#define isodigit(c) ((c) >= '0' && (c) <= '7')
  260 +static char *unescape(char *str)
  261 +{
  262 + char *in = str;
  263 + char *out = str;
  264 +
  265 + while (*in) {
  266 + if (*in == '\\') {
  267 + if (in[1] == '\\') {
  268 + *out++ = '\\';
  269 + in += 2;
  270 + continue;
  271 + } else if (in[1] == 't') {
  272 + *out++ = '\t';
  273 + in += 2;
  274 + continue;
  275 + } else if (in[1] == 'n') {
  276 + *out++ = '\n';
  277 + in += 2;
  278 + continue;
  279 + } else if (isodigit(in[1]) &&
  280 + isodigit(in[2]) &&
  281 + isodigit(in[3])) {
  282 + *out++ = ((in[1] - '0')<<6) |
  283 + ((in[2] - '0')<<3) |
  284 + (in[3] - '0');
  285 + in += 4;
  286 + continue;
  287 + }
  288 + }
  289 + *out++ = *in++;
  290 + }
  291 + *out = '\0';
  292 +
  293 + return str;
  294 +}
  295 +
  296 +/*
  297 + * Parse words[] as a ddebug query specification, which is a series
  298 + * of (keyword, value) pairs chosen from these possibilities:
  299 + *
  300 + * func <function-name>
  301 + * file <full-pathname>
  302 + * file <base-filename>
  303 + * module <module-name>
  304 + * format <escaped-string-to-find-in-format>
  305 + * line <lineno>
  306 + * line <first-lineno>-<last-lineno> // where either may be empty
  307 + */
  308 +static int ddebug_parse_query(char *words[], int nwords,
  309 + struct ddebug_query *query)
  310 +{
  311 + unsigned int i;
  312 +
  313 + /* check we have an even number of words */
  314 + if (nwords % 2 != 0)
  315 + return -EINVAL;
  316 + memset(query, 0, sizeof(*query));
  317 +
  318 + for (i = 0 ; i < nwords ; i += 2) {
  319 + if (!strcmp(words[i], "func"))
  320 + query->function = words[i+1];
  321 + else if (!strcmp(words[i], "file"))
  322 + query->filename = words[i+1];
  323 + else if (!strcmp(words[i], "module"))
  324 + query->module = words[i+1];
  325 + else if (!strcmp(words[i], "format"))
  326 + query->format = unescape(words[i+1]);
  327 + else if (!strcmp(words[i], "line")) {
  328 + char *first = words[i+1];
  329 + char *last = strchr(first, '-');
  330 + if (last)
  331 + *last++ = '\0';
  332 + if (parse_lineno(first, &query->first_lineno) < 0)
  333 + return -EINVAL;
  334 + if (last != NULL) {
  335 + /* range <first>-<last> */
  336 + if (parse_lineno(last, &query->last_lineno) < 0)
  337 + return -EINVAL;
  338 + } else {
  339 + query->last_lineno = query->first_lineno;
  340 + }
  341 + } else {
  342 + if (verbose)
  343 + printk(KERN_ERR "%s: unknown keyword \"%s\"\n",
  344 + __func__, words[i]);
  345 + return -EINVAL;
  346 + }
  347 + }
  348 +
  349 + if (verbose)
  350 + printk(KERN_INFO "%s: q->function=\"%s\" q->filename=\"%s\" "
  351 + "q->module=\"%s\" q->format=\"%s\" q->lineno=%u-%u\n",
  352 + __func__, query->function, query->filename,
  353 + query->module, query->format, query->first_lineno,
  354 + query->last_lineno);
  355 +
  356 + return 0;
  357 +}
  358 +
  359 +/*
  360 + * Parse `str' as a flags specification, format [-+=][p]+.
  361 + * Sets up *maskp and *flagsp to be used when changing the
  362 + * flags fields of matched _ddebug's. Returns 0 on success
  363 + * or <0 on error.
  364 + */
  365 +static int ddebug_parse_flags(const char *str, unsigned int *flagsp,
  366 + unsigned int *maskp)
  367 +{
  368 + unsigned flags = 0;
  369 + int op = '=';
  370 +
  371 + switch (*str) {
  372 + case '+':
  373 + case '-':
  374 + case '=':
  375 + op = *str++;
  376 + break;
  377 + default:
  378 + return -EINVAL;
  379 + }
  380 + if (verbose)
  381 + printk(KERN_INFO "%s: op='%c'\n", __func__, op);
  382 +
  383 + for ( ; *str ; ++str) {
  384 + switch (*str) {
  385 + case 'p':
  386 + flags |= _DPRINTK_FLAGS_PRINT;
  387 + break;
  388 + default:
  389 + return -EINVAL;
  390 + }
  391 + }
  392 + if (flags == 0)
  393 + return -EINVAL;
  394 + if (verbose)
  395 + printk(KERN_INFO "%s: flags=0x%x\n", __func__, flags);
  396 +
  397 + /* calculate final *flagsp, *maskp according to mask and op */
  398 + switch (op) {
  399 + case '=':
  400 + *maskp = 0;
  401 + *flagsp = flags;
  402 + break;
  403 + case '+':
  404 + *maskp = ~0U;
  405 + *flagsp = flags;
  406 + break;
  407 + case '-':
  408 + *maskp = ~flags;
  409 + *flagsp = 0;
  410 + break;
  411 + }
  412 + if (verbose)
  413 + printk(KERN_INFO "%s: *flagsp=0x%x *maskp=0x%x\n",
  414 + __func__, *flagsp, *maskp);
  415 + return 0;
  416 +}
  417 +
  418 +/*
  419 + * File_ops->write method for <debugfs>/dynamic_debug/conrol. Gathers the
  420 + * command text from userspace, parses and executes it.
  421 + */
  422 +static ssize_t ddebug_proc_write(struct file *file, const char __user *ubuf,
  423 + size_t len, loff_t *offp)
  424 +{
  425 + unsigned int flags = 0, mask = 0;
  426 + struct ddebug_query query;
  427 +#define MAXWORDS 9
  428 + int nwords;
  429 + char *words[MAXWORDS];
  430 + char tmpbuf[256];
  431 +
  432 + if (len == 0)
  433 + return 0;
  434 + /* we don't check *offp -- multiple writes() are allowed */
  435 + if (len > sizeof(tmpbuf)-1)
  436 + return -E2BIG;
  437 + if (copy_from_user(tmpbuf, ubuf, len))
  438 + return -EFAULT;
  439 + tmpbuf[len] = '\0';
  440 + if (verbose)
  441 + printk(KERN_INFO "%s: read %d bytes from userspace\n",
  442 + __func__, (int)len);
  443 +
  444 + nwords = ddebug_tokenize(tmpbuf, words, MAXWORDS);
  445 + if (nwords < 0)
  446 + return -EINVAL;
  447 + if (ddebug_parse_query(words, nwords-1, &query))
  448 + return -EINVAL;
  449 + if (ddebug_parse_flags(words[nwords-1], &flags, &mask))
  450 + return -EINVAL;
  451 +
  452 + /* actually go and implement the change */
  453 + ddebug_change(&query, flags, mask);
  454 +
  455 + *offp += len;
  456 + return len;
  457 +}
  458 +
  459 +/*
  460 + * Set the iterator to point to the first _ddebug object
  461 + * and return a pointer to that first object. Returns
  462 + * NULL if there are no _ddebugs at all.
  463 + */
  464 +static struct _ddebug *ddebug_iter_first(struct ddebug_iter *iter)
  465 +{
  466 + if (list_empty(&ddebug_tables)) {
  467 + iter->table = NULL;
  468 + iter->idx = 0;
  469 + return NULL;
  470 + }
  471 + iter->table = list_entry(ddebug_tables.next,
  472 + struct ddebug_table, link);
  473 + iter->idx = 0;
  474 + return &iter->table->ddebugs[iter->idx];
  475 +}
  476 +
  477 +/*
  478 + * Advance the iterator to point to the next _ddebug
  479 + * object from the one the iterator currently points at,
  480 + * and returns a pointer to the new _ddebug. Returns
  481 + * NULL if the iterator has seen all the _ddebugs.
  482 + */
  483 +static struct _ddebug *ddebug_iter_next(struct ddebug_iter *iter)
  484 +{
  485 + if (iter->table == NULL)
  486 + return NULL;
  487 + if (++iter->idx == iter->table->num_ddebugs) {
  488 + /* iterate to next table */
  489 + iter->idx = 0;
  490 + if (list_is_last(&iter->table->link, &ddebug_tables)) {
  491 + iter->table = NULL;
  492 + return NULL;
  493 + }
  494 + iter->table = list_entry(iter->table->link.next,
  495 + struct ddebug_table, link);
  496 + }
  497 + return &iter->table->ddebugs[iter->idx];
  498 +}
  499 +
  500 +/*
  501 + * Seq_ops start method. Called at the start of every
  502 + * read() call from userspace. Takes the ddebug_lock and
  503 + * seeks the seq_file's iterator to the given position.
  504 + */
  505 +static void *ddebug_proc_start(struct seq_file *m, loff_t *pos)
  506 +{
  507 + struct ddebug_iter *iter = m->private;
  508 + struct _ddebug *dp;
  509 + int n = *pos;
  510 +
  511 + if (verbose)
  512 + printk(KERN_INFO "%s: called m=%p *pos=%lld\n",
  513 + __func__, m, (unsigned long long)*pos);
  514 +
  515 + mutex_lock(&ddebug_lock);
  516 +
  517 + if (!n)
  518 + return SEQ_START_TOKEN;
  519 + if (n < 0)
  520 + return NULL;
  521 + dp = ddebug_iter_first(iter);
  522 + while (dp != NULL && --n > 0)
  523 + dp = ddebug_iter_next(iter);
  524 + return dp;
  525 +}
  526 +
  527 +/*
  528 + * Seq_ops next method. Called several times within a read()
  529 + * call from userspace, with ddebug_lock held. Walks to the
  530 + * next _ddebug object with a special case for the header line.
  531 + */
  532 +static void *ddebug_proc_next(struct seq_file *m, void *p, loff_t *pos)
  533 +{
  534 + struct ddebug_iter *iter = m->private;
  535 + struct _ddebug *dp;
  536 +
  537 + if (verbose)
  538 + printk(KERN_INFO "%s: called m=%p p=%p *pos=%lld\n",
  539 + __func__, m, p, (unsigned long long)*pos);
  540 +
  541 + if (p == SEQ_START_TOKEN)
  542 + dp = ddebug_iter_first(iter);
  543 + else
  544 + dp = ddebug_iter_next(iter);
  545 + ++*pos;
  546 + return dp;
  547 +}
  548 +
  549 +/*
  550 + * Seq_ops show method. Called several times within a read()
  551 + * call from userspace, with ddebug_lock held. Formats the
  552 + * current _ddebug as a single human-readable line, with a
  553 + * special case for the header line.
  554 + */
  555 +static int ddebug_proc_show(struct seq_file *m, void *p)
  556 +{
  557 + struct ddebug_iter *iter = m->private;
  558 + struct _ddebug *dp = p;
  559 + char flagsbuf[8];
  560 +
  561 + if (verbose)
  562 + printk(KERN_INFO "%s: called m=%p p=%p\n",
  563 + __func__, m, p);
  564 +
  565 + if (p == SEQ_START_TOKEN) {
  566 + seq_puts(m,
  567 + "# filename:lineno [module]function flags format\n");
  568 + return 0;
  569 + }
  570 +
  571 + seq_printf(m, "%s:%u [%s]%s %s \"",
  572 + dp->filename, dp->lineno,
  573 + iter->table->mod_name, dp->function,
  574 + ddebug_describe_flags(dp, flagsbuf, sizeof(flagsbuf)));
  575 + seq_escape(m, dp->format, "\t\r\n\"");
  576 + seq_puts(m, "\"\n");
  577 +
  578 + return 0;
  579 +}
  580 +
  581 +/*
  582 + * Seq_ops stop method. Called at the end of each read()
  583 + * call from userspace. Drops ddebug_lock.
  584 + */
  585 +static void ddebug_proc_stop(struct seq_file *m, void *p)
  586 +{
  587 + if (verbose)
  588 + printk(KERN_INFO "%s: called m=%p p=%p\n",
  589 + __func__, m, p);
  590 + mutex_unlock(&ddebug_lock);
  591 +}
  592 +
  593 +static const struct seq_operations ddebug_proc_seqops = {
  594 + .start = ddebug_proc_start,
  595 + .next = ddebug_proc_next,
  596 + .show = ddebug_proc_show,
  597 + .stop = ddebug_proc_stop
  598 +};
  599 +
  600 +/*
  601 + * File_ops->open method for <debugfs>/dynamic_debug/control. Does the seq_file
  602 + * setup dance, and also creates an iterator to walk the _ddebugs.
  603 + * Note that we create a seq_file always, even for O_WRONLY files
  604 + * where it's not needed, as doing so simplifies the ->release method.
  605 + */
  606 +static int ddebug_proc_open(struct inode *inode, struct file *file)
  607 +{
  608 + struct ddebug_iter *iter;
  609 + int err;
  610 +
  611 + if (verbose)
  612 + printk(KERN_INFO "%s: called\n", __func__);
  613 +
  614 + iter = kzalloc(sizeof(*iter), GFP_KERNEL);
  615 + if (iter == NULL)
  616 + return -ENOMEM;
  617 +
  618 + err = seq_open(file, &ddebug_proc_seqops);
  619 + if (err) {
  620 + kfree(iter);
  621 + return err;
  622 + }
  623 + ((struct seq_file *) file->private_data)->private = iter;
  624 + return 0;
  625 +}
  626 +
  627 +static const struct file_operations ddebug_proc_fops = {
  628 + .owner = THIS_MODULE,
  629 + .open = ddebug_proc_open,
  630 + .read = seq_read,
  631 + .llseek = seq_lseek,
  632 + .release = seq_release_private,
  633 + .write = ddebug_proc_write
  634 +};
  635 +
  636 +/*
  637 + * Allocate a new ddebug_table for the given module
  638 + * and add it to the global list.
  639 + */
  640 +int ddebug_add_module(struct _ddebug *tab, unsigned int n,
  641 + const char *name)
  642 +{
  643 + struct ddebug_table *dt;
  644 + char *new_name;
  645 +
  646 + dt = kzalloc(sizeof(*dt), GFP_KERNEL);
  647 + if (dt == NULL)
  648 + return -ENOMEM;
  649 + new_name = kstrdup(name, GFP_KERNEL);
  650 + if (new_name == NULL) {
  651 + kfree(dt);
  652 + return -ENOMEM;
  653 + }
  654 + dt->mod_name = new_name;
  655 + dt->num_ddebugs = n;
  656 + dt->num_enabled = 0;
  657 + dt->ddebugs = tab;
  658 +
  659 + mutex_lock(&ddebug_lock);
  660 + list_add_tail(&dt->link, &ddebug_tables);
  661 + mutex_unlock(&ddebug_lock);
  662 +
  663 + if (verbose)
  664 + printk(KERN_INFO "%u debug prints in module %s\n",
  665 + n, dt->mod_name);
  666 + return 0;
  667 +}
  668 +EXPORT_SYMBOL_GPL(ddebug_add_module);
  669 +
  670 +static void ddebug_table_free(struct ddebug_table *dt)
  671 +{
  672 + list_del_init(&dt->link);
  673 + kfree(dt->mod_name);
  674 + kfree(dt);
  675 +}
  676 +
  677 +/*
  678 + * Called in response to a module being unloaded. Removes
  679 + * any ddebug_table's which point at the module.
  680 + */
  681 +int ddebug_remove_module(char *mod_name)
  682 +{
  683 + struct ddebug_table *dt, *nextdt;
  684 + int ret = -ENOENT;
  685 +
  686 + if (verbose)
  687 + printk(KERN_INFO "%s: removing module \"%s\"\n",
  688 + __func__, mod_name);
  689 +
  690 + mutex_lock(&ddebug_lock);
  691 + list_for_each_entry_safe(dt, nextdt, &ddebug_tables, link) {
  692 + if (!strcmp(dt->mod_name, mod_name)) {
  693 + ddebug_table_free(dt);
  694 + ret = 0;
  695 + }
  696 + }
  697 + mutex_unlock(&ddebug_lock);
  698 + return ret;
  699 +}
  700 +EXPORT_SYMBOL_GPL(ddebug_remove_module);
  701 +
  702 +static void ddebug_remove_all_tables(void)
  703 +{
  704 + mutex_lock(&ddebug_lock);
  705 + while (!list_empty(&ddebug_tables)) {
  706 + struct ddebug_table *dt = list_entry(ddebug_tables.next,
  707 + struct ddebug_table,
  708 + link);
  709 + ddebug_table_free(dt);
  710 + }
  711 + mutex_unlock(&ddebug_lock);
  712 +}
  713 +
  714 +static int __init dynamic_debug_init(void)
  715 +{
  716 + struct dentry *dir, *file;
  717 + struct _ddebug *iter, *iter_start;
  718 + const char *modname = NULL;
  719 + int ret = 0;
  720 + int n = 0;
  721 +
  722 + dir = debugfs_create_dir("dynamic_debug", NULL);
  723 + if (!dir)
  724 + return -ENOMEM;
  725 + file = debugfs_create_file("control", 0644, dir, NULL,
  726 + &ddebug_proc_fops);
  727 + if (!file) {
  728 + debugfs_remove(dir);
  729 + return -ENOMEM;
  730 + }
  731 + if (__start___verbose != __stop___verbose) {
  732 + iter = __start___verbose;
  733 + modname = iter->modname;
  734 + iter_start = iter;
  735 + for (; iter < __stop___verbose; iter++) {
  736 + if (strcmp(modname, iter->modname)) {
  737 + ret = ddebug_add_module(iter_start, n, modname);
  738 + if (ret)
  739 + goto out_free;
  740 + n = 0;
  741 + modname = iter->modname;
  742 + iter_start = iter;
  743 + }
  744 + n++;
  745 + }
  746 + ret = ddebug_add_module(iter_start, n, modname);
  747 + }
  748 +out_free:
  749 + if (ret) {
  750 + ddebug_remove_all_tables();
  751 + debugfs_remove(dir);
  752 + debugfs_remove(file);
  753 + }
  754 + return 0;
  755 +}
  756 +module_init(dynamic_debug_init);
lib/dynamic_printk.c
View file @ e9d376f
1   -/*
2   - * lib/dynamic_printk.c
3   - *
4   - * make pr_debug()/dev_dbg() calls runtime configurable based upon their
5   - * their source module.
6   - *
7   - * Copyright (C) 2008 Red Hat, Inc., Jason Baron <jbaron@redhat.com>
8   - */
9   -
10   -#include <linux/kernel.h>
11   -#include <linux/module.h>
12   -#include <linux/uaccess.h>
13   -#include <linux/seq_file.h>
14   -#include <linux/debugfs.h>
15   -#include <linux/fs.h>
16   -
17   -extern struct mod_debug __start___verbose[];
18   -extern struct mod_debug __stop___verbose[];
19   -
20   -struct debug_name {
21   - struct hlist_node hlist;
22   - struct hlist_node hlist2;
23   - int hash1;
24   - int hash2;
25   - char *name;
26   - int enable;
27   - int type;
28   -};
29   -
30   -static int nr_entries;
31   -static int num_enabled;
32   -int dynamic_enabled = DYNAMIC_ENABLED_NONE;
33   -static struct hlist_head module_table[DEBUG_HASH_TABLE_SIZE] =
34   - { [0 ... DEBUG_HASH_TABLE_SIZE-1] = HLIST_HEAD_INIT };
35   -static struct hlist_head module_table2[DEBUG_HASH_TABLE_SIZE] =
36   - { [0 ... DEBUG_HASH_TABLE_SIZE-1] = HLIST_HEAD_INIT };
37   -static DECLARE_MUTEX(debug_list_mutex);
38   -
39   -/* dynamic_printk_enabled, and dynamic_printk_enabled2 are bitmasks in which
40   - * bit n is set to 1 if any modname hashes into the bucket n, 0 otherwise. They
41   - * use independent hash functions, to reduce the chance of false positives.
42   - */
43   -long long dynamic_printk_enabled;
44   -EXPORT_SYMBOL_GPL(dynamic_printk_enabled);
45   -long long dynamic_printk_enabled2;
46   -EXPORT_SYMBOL_GPL(dynamic_printk_enabled2);
47   -
48   -/* returns the debug module pointer. */
49   -static struct debug_name *find_debug_module(char *module_name)
50   -{
51   - int i;
52   - struct hlist_head *head;
53   - struct hlist_node *node;
54   - struct debug_name *element;
55   -
56   - element = NULL;
57   - for (i = 0; i < DEBUG_HASH_TABLE_SIZE; i++) {
58   - head = &module_table[i];
59   - hlist_for_each_entry_rcu(element, node, head, hlist)
60   - if (!strcmp(element->name, module_name))
61   - return element;
62   - }
63   - return NULL;
64   -}
65   -
66   -/* returns the debug module pointer. */
67   -static struct debug_name *find_debug_module_hash(char *module_name, int hash)
68   -{
69   - struct hlist_head *head;
70   - struct hlist_node *node;
71   - struct debug_name *element;
72   -
73   - element = NULL;
74   - head = &module_table[hash];
75   - hlist_for_each_entry_rcu(element, node, head, hlist)
76   - if (!strcmp(element->name, module_name))
77   - return element;
78   - return NULL;
79   -}
80   -
81   -/* caller must hold mutex*/
82   -static int __add_debug_module(char *mod_name, int hash, int hash2)
83   -{
84   - struct debug_name *new;
85   - char *module_name;
86   - int ret = 0;
87   -
88   - if (find_debug_module(mod_name)) {
89   - ret = -EINVAL;
90   - goto out;
91   - }
92   - module_name = kmalloc(strlen(mod_name) + 1, GFP_KERNEL);
93   - if (!module_name) {
94   - ret = -ENOMEM;
95   - goto out;
96   - }
97   - module_name = strcpy(module_name, mod_name);
98   - module_name[strlen(mod_name)] = '\0';
99   - new = kzalloc(sizeof(struct debug_name), GFP_KERNEL);
100   - if (!new) {
101   - kfree(module_name);
102   - ret = -ENOMEM;
103   - goto out;
104   - }
105   - INIT_HLIST_NODE(&new->hlist);
106   - INIT_HLIST_NODE(&new->hlist2);
107   - new->name = module_name;
108   - new->hash1 = hash;
109   - new->hash2 = hash2;
110   - hlist_add_head_rcu(&new->hlist, &module_table[hash]);
111   - hlist_add_head_rcu(&new->hlist2, &module_table2[hash2]);
112   - nr_entries++;
113   -out:
114   - return ret;
115   -}
116   -
117   -int unregister_dynamic_debug_module(char *mod_name)
118   -{
119   - struct debug_name *element;
120   - int ret = 0;
121   -
122   - down(&debug_list_mutex);
123   - element = find_debug_module(mod_name);
124   - if (!element) {
125   - ret = -EINVAL;
126   - goto out;
127   - }
128   - hlist_del_rcu(&element->hlist);
129   - hlist_del_rcu(&element->hlist2);
130   - synchronize_rcu();
131   - kfree(element->name);
132   - if (element->enable)
133   - num_enabled--;
134   - kfree(element);
135   - nr_entries--;
136   -out:
137   - up(&debug_list_mutex);
138   - return ret;
139   -}
140   -EXPORT_SYMBOL_GPL(unregister_dynamic_debug_module);
141   -
142   -int register_dynamic_debug_module(char *mod_name, int type, char *share_name,
143   - char *flags, int hash, int hash2)
144   -{
145   - struct debug_name *elem;
146   - int ret = 0;
147   -
148   - down(&debug_list_mutex);
149   - elem = find_debug_module(mod_name);
150   - if (!elem) {
151   - if (__add_debug_module(mod_name, hash, hash2))
152   - goto out;
153   - elem = find_debug_module(mod_name);
154   - if (dynamic_enabled == DYNAMIC_ENABLED_ALL &&
155   - !strcmp(mod_name, share_name)) {
156   - elem->enable = true;
157   - num_enabled++;
158   - }
159   - }
160   - elem->type |= type;
161   -out:
162   - up(&debug_list_mutex);
163   - return ret;
164   -}
165   -EXPORT_SYMBOL_GPL(register_dynamic_debug_module);
166   -
167   -int __dynamic_dbg_enabled_helper(char *mod_name, int type, int value, int hash)
168   -{
169   - struct debug_name *elem;
170   - int ret = 0;
171   -
172   - if (dynamic_enabled == DYNAMIC_ENABLED_ALL)
173   - return 1;
174   - rcu_read_lock();
175   - elem = find_debug_module_hash(mod_name, hash);
176   - if (elem && elem->enable)
177   - ret = 1;
178   - rcu_read_unlock();
179   - return ret;
180   -}
181   -EXPORT_SYMBOL_GPL(__dynamic_dbg_enabled_helper);
182   -
183   -static void set_all(bool enable)
184   -{
185   - struct debug_name *e;
186   - struct hlist_node *node;
187   - int i;
188   - long long enable_mask;
189   -
190   - for (i = 0; i < DEBUG_HASH_TABLE_SIZE; i++) {
191   - if (module_table[i].first != NULL) {
192   - hlist_for_each_entry(e, node, &module_table[i], hlist) {
193   - e->enable = enable;
194   - }
195   - }
196   - }
197   - if (enable)
198   - enable_mask = ULLONG_MAX;
199   - else
200   - enable_mask = 0;
201   - dynamic_printk_enabled = enable_mask;
202   - dynamic_printk_enabled2 = enable_mask;
203   -}
204   -
205   -static int disabled_hash(int i, bool first_table)
206   -{
207   - struct debug_name *e;
208   - struct hlist_node *node;
209   -
210   - if (first_table) {
211   - hlist_for_each_entry(e, node, &module_table[i], hlist) {
212   - if (e->enable)
213   - return 0;
214   - }
215   - } else {
216   - hlist_for_each_entry(e, node, &module_table2[i], hlist2) {
217   - if (e->enable)
218   - return 0;
219   - }
220   - }
221   - return 1;
222   -}
223   -
224   -static ssize_t pr_debug_write(struct file *file, const char __user *buf,
225   - size_t length, loff_t *ppos)
226   -{
227   - char *buffer, *s, *value_str, *setting_str;
228   - int err, value;
229   - struct debug_name *elem = NULL;
230   - int all = 0;
231   -
232   - if (length > PAGE_SIZE || length < 0)
233   - return -EINVAL;
234   -
235   - buffer = (char *)__get_free_page(GFP_KERNEL);
236   - if (!buffer)
237   - return -ENOMEM;
238   -
239   - err = -EFAULT;
240   - if (copy_from_user(buffer, buf, length))
241   - goto out;
242   -
243   - err = -EINVAL;
244   - if (length < PAGE_SIZE)
245   - buffer[length] = '\0';
246   - else if (buffer[PAGE_SIZE-1])
247   - goto out;
248   -
249   - err = -EINVAL;
250   - down(&debug_list_mutex);
251   -
252   - if (strncmp("set", buffer, 3))
253   - goto out_up;
254   - s = buffer + 3;
255   - setting_str = strsep(&s, "=");
256   - if (s == NULL)
257   - goto out_up;
258   - setting_str = strstrip(setting_str);
259   - value_str = strsep(&s, " ");
260   - if (s == NULL)
261   - goto out_up;
262   - s = strstrip(s);
263   - if (!strncmp(s, "all", 3))
264   - all = 1;
265   - else
266   - elem = find_debug_module(s);
267   - if (!strncmp(setting_str, "enable", 6)) {
268   - value = !!simple_strtol(value_str, NULL, 10);
269   - if (all) {
270   - if (value) {
271   - set_all(true);
272   - num_enabled = nr_entries;
273   - dynamic_enabled = DYNAMIC_ENABLED_ALL;
274   - } else {
275   - set_all(false);
276   - num_enabled = 0;
277   - dynamic_enabled = DYNAMIC_ENABLED_NONE;
278   - }
279   - err = 0;
280   - } else if (elem) {
281   - if (value && (elem->enable == 0)) {
282   - dynamic_printk_enabled |= (1LL << elem->hash1);
283   - dynamic_printk_enabled2 |= (1LL << elem->hash2);
284   - elem->enable = 1;
285   - num_enabled++;
286   - dynamic_enabled = DYNAMIC_ENABLED_SOME;
287   - err = 0;
288   - printk(KERN_DEBUG
289   - "debugging enabled for module %s\n",
290   - elem->name);
291   - } else if (!value && (elem->enable == 1)) {
292   - elem->enable = 0;
293   - num_enabled--;
294   - if (disabled_hash(elem->hash1, true))
295   - dynamic_printk_enabled &=
296   - ~(1LL << elem->hash1);
297   - if (disabled_hash(elem->hash2, false))
298   - dynamic_printk_enabled2 &=
299   - ~(1LL << elem->hash2);
300   - if (num_enabled)
301   - dynamic_enabled = DYNAMIC_ENABLED_SOME;
302   - else
303   - dynamic_enabled = DYNAMIC_ENABLED_NONE;
304   - err = 0;
305   - printk(KERN_DEBUG
306   - "debugging disabled for module %s\n",
307   - elem->name);
308   - }
309   - }
310   - }
311   - if (!err)
312   - err = length;
313   -out_up:
314   - up(&debug_list_mutex);
315   -out:
316   - free_page((unsigned long)buffer);
317   - return err;
318   -}
319   -
320   -static void *pr_debug_seq_start(struct seq_file *f, loff_t *pos)
321   -{
322   - return (*pos < DEBUG_HASH_TABLE_SIZE) ? pos : NULL;
323   -}
324   -
325   -static void *pr_debug_seq_next(struct seq_file *s, void *v, loff_t *pos)
326   -{
327   - (*pos)++;
328   - if (*pos >= DEBUG_HASH_TABLE_SIZE)
329   - return NULL;
330   - return pos;
331   -}
332   -
333   -static void pr_debug_seq_stop(struct seq_file *s, void *v)
334   -{
335   - /* Nothing to do */
336   -}
337   -
338   -static int pr_debug_seq_show(struct seq_file *s, void *v)
339   -{
340   - struct hlist_head *head;
341   - struct hlist_node *node;
342   - struct debug_name *elem;
343   - unsigned int i = *(loff_t *) v;
344   -
345   - rcu_read_lock();
346   - head = &module_table[i];
347   - hlist_for_each_entry_rcu(elem, node, head, hlist) {
348   - seq_printf(s, "%s enabled=%d", elem->name, elem->enable);
349   - seq_printf(s, "\n");
350   - }
351   - rcu_read_unlock();
352   - return 0;
353   -}
354   -
355   -static struct seq_operations pr_debug_seq_ops = {
356   - .start = pr_debug_seq_start,
357   - .next = pr_debug_seq_next,
358   - .stop = pr_debug_seq_stop,
359   - .show = pr_debug_seq_show
360   -};
361   -
362   -static int pr_debug_open(struct inode *inode, struct file *filp)
363   -{
364   - return seq_open(filp, &pr_debug_seq_ops);
365   -}
366   -
367   -static const struct file_operations pr_debug_operations = {
368   - .open = pr_debug_open,
369   - .read = seq_read,
370   - .write = pr_debug_write,
371   - .llseek = seq_lseek,
372   - .release = seq_release,
373   -};
374   -
375   -static int __init dynamic_printk_init(void)
376   -{
377   - struct dentry *dir, *file;
378   - struct mod_debug *iter;
379   - unsigned long value;
380   -
381   - dir = debugfs_create_dir("dynamic_printk", NULL);
382   - if (!dir)
383   - return -ENOMEM;
384   - file = debugfs_create_file("modules", 0644, dir, NULL,
385   - &pr_debug_operations);
386   - if (!file) {
387   - debugfs_remove(dir);
388   - return -ENOMEM;
389   - }
390   - for (value = (unsigned long)__start___verbose;
391   - value < (unsigned long)__stop___verbose;
392   - value += sizeof(struct mod_debug)) {
393   - iter = (struct mod_debug *)value;
394   - register_dynamic_debug_module(iter->modname,
395   - iter->type,
396   - iter->logical_modname,
397   - iter->flag_names, iter->hash, iter->hash2);
398   - }
399   - if (dynamic_enabled == DYNAMIC_ENABLED_ALL)
400   - set_all(true);
401   - return 0;
402   -}
403   -module_init(dynamic_printk_init);
404   -/* may want to move this earlier so we can get traces as early as possible */
405   -
406   -static int __init dynamic_printk_setup(char *str)
407   -{
408   - if (str)
409   - return -ENOENT;
410   - dynamic_enabled = DYNAMIC_ENABLED_ALL;
411   - return 0;
412   -}
413   -/* Use early_param(), so we can get debug output as early as possible */
414   -early_param("dynamic_printk", dynamic_printk_setup);
net/netfilter/nf_conntrack_pptp.c
Diff comments   View file @ e9d376f
... ... @@ -66,7 +66,7 @@
66 66 struct nf_conntrack_expect *exp) __read_mostly;
67 67 EXPORT_SYMBOL_GPL(nf_nat_pptp_hook_expectfn);
68 68  
69   -#if defined(DEBUG) || defined(CONFIG_DYNAMIC_PRINTK_DEBUG)
  69 +#if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG)
70 70 /* PptpControlMessageType names */
71 71 const char *const pptp_msg_name[] = {
72 72 "UNKNOWN_MESSAGE",
scripts/Makefile.lib
Diff comments   View file @ e9d376f
... ... @@ -97,7 +97,7 @@
97 97 -D"KBUILD_MODNAME=KBUILD_STR($(call name-fix,$(modname)))")
98 98  
99 99 #hash values
100   -ifdef CONFIG_DYNAMIC_PRINTK_DEBUG
  100 +ifdef CONFIG_DYNAMIC_DEBUG
101 101 debug_flags = -D"DEBUG_HASH=$(shell ./scripts/basic/hash djb2 $(@D)$(modname))"\
102 102 -D"DEBUG_HASH2=$(shell ./scripts/basic/hash r5 $(@D)$(modname))"
103 103 else