4 * make pr_debug()/dev_dbg() calls runtime configurable based upon their
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 * Copyright (C) 2011 Bart Van Assche. All Rights Reserved.
11 * Copyright (C) 2013 Du, Changbin <changbin.du@gmail.com>
14 #define pr_fmt(fmt) "dyndbg: " fmt
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/moduleparam.h>
19 #include <linux/kallsyms.h>
20 #include <linux/types.h>
21 #include <linux/mutex.h>
22 #include <linux/proc_fs.h>
23 #include <linux/seq_file.h>
24 #include <linux/list.h>
25 #include <linux/sysctl.h>
26 #include <linux/ctype.h>
27 #include <linux/string.h>
28 #include <linux/parser.h>
29 #include <linux/string_helpers.h>
30 #include <linux/uaccess.h>
31 #include <linux/dynamic_debug.h>
32 #include <linux/debugfs.h>
33 #include <linux/slab.h>
34 #include <linux/jump_label.h>
35 #include <linux/hardirq.h>
36 #include <linux/sched.h>
37 #include <linux/device.h>
38 #include <linux/netdevice.h>
40 #include <rdma/ib_verbs.h>
42 extern struct _ddebug __start___dyndbg[];
43 extern struct _ddebug __stop___dyndbg[];
46 struct list_head link;
48 unsigned int num_ddebugs;
49 struct _ddebug *ddebugs;
57 unsigned int first_lineno, last_lineno;
61 struct ddebug_table *table;
65 struct flag_settings {
70 static DEFINE_MUTEX(ddebug_lock);
71 static LIST_HEAD(ddebug_tables);
73 module_param(verbose, int, 0644);
75 /* Return the path relative to source root */
76 static inline const char *trim_prefix(const char *path)
78 int skip = strlen(__FILE__) - strlen("lib/dynamic_debug.c");
80 if (strncmp(path, __FILE__, skip))
81 skip = 0; /* prefix mismatch, don't skip */
86 static struct { unsigned flag:8; char opt_char; } opt_array[] = {
87 { _DPRINTK_FLAGS_PRINT, 'p' },
88 { _DPRINTK_FLAGS_INCL_MODNAME, 'm' },
89 { _DPRINTK_FLAGS_INCL_FUNCNAME, 'f' },
90 { _DPRINTK_FLAGS_INCL_LINENO, 'l' },
91 { _DPRINTK_FLAGS_INCL_TID, 't' },
92 { _DPRINTK_FLAGS_NONE, '_' },
95 struct flagsbuf { char buf[ARRAY_SIZE(opt_array)+1]; };
97 /* format a string into buf[] which describes the _ddebug's flags */
98 static char *ddebug_describe_flags(unsigned int flags, struct flagsbuf *fb)
103 for (i = 0; i < ARRAY_SIZE(opt_array); ++i)
104 if (flags & opt_array[i].flag)
105 *p++ = opt_array[i].opt_char;
113 #define vnpr_info(lvl, fmt, ...) \
115 if (verbose >= lvl) \
116 pr_info(fmt, ##__VA_ARGS__); \
119 #define vpr_info(fmt, ...) vnpr_info(1, fmt, ##__VA_ARGS__)
120 #define v2pr_info(fmt, ...) vnpr_info(2, fmt, ##__VA_ARGS__)
122 static void vpr_info_dq(const struct ddebug_query *query, const char *msg)
124 /* trim any trailing newlines */
128 fmtlen = strlen(query->format);
129 while (fmtlen && query->format[fmtlen - 1] == '\n')
133 vpr_info("%s: func=\"%s\" file=\"%s\" module=\"%s\" format=\"%.*s\" lineno=%u-%u\n",
135 query->function ?: "",
136 query->filename ?: "",
138 fmtlen, query->format ?: "",
139 query->first_lineno, query->last_lineno);
143 * Search the tables for _ddebug's which match the given `query' and
144 * apply the `flags' and `mask' to them. Returns number of matching
145 * callsites, normally the same as number of changes. If verbose,
146 * logs the changes. Takes ddebug_lock.
148 static int ddebug_change(const struct ddebug_query *query,
149 struct flag_settings *modifiers)
152 struct ddebug_table *dt;
153 unsigned int newflags;
154 unsigned int nfound = 0;
155 struct flagsbuf fbuf;
157 /* search for matching ddebugs */
158 mutex_lock(&ddebug_lock);
159 list_for_each_entry(dt, &ddebug_tables, link) {
161 /* match against the module name */
163 !match_wildcard(query->module, dt->mod_name))
166 for (i = 0; i < dt->num_ddebugs; i++) {
167 struct _ddebug *dp = &dt->ddebugs[i];
169 /* match against the source filename */
170 if (query->filename &&
171 !match_wildcard(query->filename, dp->filename) &&
172 !match_wildcard(query->filename,
173 kbasename(dp->filename)) &&
174 !match_wildcard(query->filename,
175 trim_prefix(dp->filename)))
178 /* match against the function */
179 if (query->function &&
180 !match_wildcard(query->function, dp->function))
183 /* match against the format */
185 if (*query->format == '^') {
187 /* anchored search. match must be at beginning */
188 p = strstr(dp->format, query->format+1);
191 } else if (!strstr(dp->format, query->format))
195 /* match against the line number range */
196 if (query->first_lineno &&
197 dp->lineno < query->first_lineno)
199 if (query->last_lineno &&
200 dp->lineno > query->last_lineno)
205 newflags = (dp->flags & modifiers->mask) | modifiers->flags;
206 if (newflags == dp->flags)
208 #ifdef CONFIG_JUMP_LABEL
209 if (dp->flags & _DPRINTK_FLAGS_PRINT) {
210 if (!(newflags & _DPRINTK_FLAGS_PRINT))
211 static_branch_disable(&dp->key.dd_key_true);
212 } else if (newflags & _DPRINTK_FLAGS_PRINT) {
213 static_branch_enable(&dp->key.dd_key_true);
216 dp->flags = newflags;
217 v2pr_info("changed %s:%d [%s]%s =%s\n",
218 trim_prefix(dp->filename), dp->lineno,
219 dt->mod_name, dp->function,
220 ddebug_describe_flags(dp->flags, &fbuf));
223 mutex_unlock(&ddebug_lock);
225 if (!nfound && verbose)
226 pr_info("no matches for query\n");
232 * Split the buffer `buf' into space-separated words.
233 * Handles simple " and ' quoting, i.e. without nested,
234 * embedded or escaped \". Return the number of words
237 static int ddebug_tokenize(char *buf, char *words[], int maxwords)
244 /* Skip leading whitespace */
245 buf = skip_spaces(buf);
247 break; /* oh, it was trailing whitespace */
249 break; /* token starts comment, skip rest of line */
251 /* find `end' of word, whitespace separated or quoted */
252 if (*buf == '"' || *buf == '\'') {
254 for (end = buf; *end && *end != quote; end++)
257 pr_err("unclosed quote: %s\n", buf);
258 return -EINVAL; /* unclosed quote */
261 for (end = buf; *end && !isspace(*end); end++)
266 /* `buf' is start of word, `end' is one past its end */
267 if (nwords == maxwords) {
268 pr_err("too many words, legal max <=%d\n", maxwords);
269 return -EINVAL; /* ran out of words[] before bytes */
272 *end++ = '\0'; /* terminate the word */
273 words[nwords++] = buf;
279 pr_info("split into words:");
280 for (i = 0; i < nwords; i++)
281 pr_cont(" \"%s\"", words[i]);
289 * Parse a single line number. Note that the empty string ""
290 * is treated as a special case and converted to zero, which
291 * is later treated as a "don't care" value.
293 static inline int parse_lineno(const char *str, unsigned int *val)
300 if (kstrtouint(str, 10, val) < 0) {
301 pr_err("bad line-number: %s\n", str);
307 static int parse_linerange(struct ddebug_query *query, const char *first)
309 char *last = strchr(first, '-');
311 if (query->first_lineno || query->last_lineno) {
312 pr_err("match-spec: line used 2x\n");
317 if (parse_lineno(first, &query->first_lineno) < 0)
320 /* range <first>-<last> */
321 if (parse_lineno(last, &query->last_lineno) < 0)
324 /* special case for last lineno not specified */
325 if (query->last_lineno == 0)
326 query->last_lineno = UINT_MAX;
328 if (query->last_lineno < query->first_lineno) {
329 pr_err("last-line:%d < 1st-line:%d\n",
331 query->first_lineno);
335 query->last_lineno = query->first_lineno;
337 vpr_info("parsed line %d-%d\n", query->first_lineno,
342 static int check_set(const char **dest, char *src, char *name)
348 pr_err("match-spec:%s val:%s overridden by %s\n",
356 * Parse words[] as a ddebug query specification, which is a series
357 * of (keyword, value) pairs chosen from these possibilities:
359 * func <function-name>
360 * file <full-pathname>
361 * file <base-filename>
362 * module <module-name>
363 * format <escaped-string-to-find-in-format>
365 * line <first-lineno>-<last-lineno> // where either may be empty
367 * Only 1 of each type is allowed.
368 * Returns 0 on success, <0 on error.
370 static int ddebug_parse_query(char *words[], int nwords,
371 struct ddebug_query *query, const char *modname)
377 /* check we have an even number of words */
378 if (nwords % 2 != 0) {
379 pr_err("expecting pairs of match-spec <value>\n");
383 for (i = 0; i < nwords; i += 2) {
384 char *keyword = words[i];
385 char *arg = words[i+1];
387 if (!strcmp(keyword, "func")) {
388 rc = check_set(&query->function, arg, "func");
389 } else if (!strcmp(keyword, "file")) {
390 if (check_set(&query->filename, arg, "file"))
393 /* tail :$info is function or line-range */
394 fline = strchr(query->filename, ':');
398 if (isalpha(*fline) || *fline == '*' || *fline == '?') {
399 /* take as function name */
400 if (check_set(&query->function, fline, "func"))
403 if (parse_linerange(query, fline))
406 } else if (!strcmp(keyword, "module")) {
407 rc = check_set(&query->module, arg, "module");
408 } else if (!strcmp(keyword, "format")) {
409 string_unescape_inplace(arg, UNESCAPE_SPACE |
412 rc = check_set(&query->format, arg, "format");
413 } else if (!strcmp(keyword, "line")) {
414 if (parse_linerange(query, arg))
417 pr_err("unknown keyword \"%s\"\n", keyword);
423 if (!query->module && modname)
425 * support $modname.dyndbg=<multiple queries>, when
426 * not given in the query itself
428 query->module = modname;
430 vpr_info_dq(query, "parsed");
435 * Parse `str' as a flags specification, format [-+=][p]+.
436 * Sets up *maskp and *flagsp to be used when changing the
437 * flags fields of matched _ddebug's. Returns 0 on success
440 static int ddebug_parse_flags(const char *str, struct flag_settings *modifiers)
451 pr_err("bad flag-op %c, at start of %s\n", *str, str);
454 vpr_info("op='%c'\n", op);
456 for (; *str ; ++str) {
457 for (i = ARRAY_SIZE(opt_array) - 1; i >= 0; i--) {
458 if (*str == opt_array[i].opt_char) {
459 modifiers->flags |= opt_array[i].flag;
464 pr_err("unknown flag '%c'\n", *str);
468 vpr_info("flags=0x%x\n", modifiers->flags);
470 /* calculate final flags, mask based upon op */
473 /* modifiers->flags already set */
477 modifiers->mask = ~0U;
480 modifiers->mask = ~modifiers->flags;
481 modifiers->flags = 0;
484 vpr_info("*flagsp=0x%x *maskp=0x%x\n", modifiers->flags, modifiers->mask);
489 static int ddebug_exec_query(char *query_string, const char *modname)
491 struct flag_settings modifiers = {};
492 struct ddebug_query query = {};
495 char *words[MAXWORDS];
497 nwords = ddebug_tokenize(query_string, words, MAXWORDS);
499 pr_err("tokenize failed\n");
502 /* check flags 1st (last arg) so query is pairs of spec,val */
503 if (ddebug_parse_flags(words[nwords-1], &modifiers)) {
504 pr_err("flags parse failed\n");
507 if (ddebug_parse_query(words, nwords-1, &query, modname)) {
508 pr_err("query parse failed\n");
511 /* actually go and implement the change */
512 nfound = ddebug_change(&query, &modifiers);
513 vpr_info_dq(&query, nfound ? "applied" : "no-match");
518 /* handle multiple queries in query string, continue on error, return
519 last error or number of matching callsites. Module name is either
520 in param (for boot arg) or perhaps in query string.
522 static int ddebug_exec_queries(char *query, const char *modname)
525 int i, errs = 0, exitcode = 0, rc, nfound = 0;
527 for (i = 0; query; query = split) {
528 split = strpbrk(query, ";\n");
532 query = skip_spaces(query);
533 if (!query || !*query || *query == '#')
536 vpr_info("query %d: \"%s\"\n", i, query);
538 rc = ddebug_exec_query(query, modname);
547 vpr_info("processed %d queries, with %d matches, %d errs\n",
555 #define PREFIX_SIZE 64
557 static int remaining(int wrote)
559 if (PREFIX_SIZE - wrote > 0)
560 return PREFIX_SIZE - wrote;
564 static char *dynamic_emit_prefix(const struct _ddebug *desc, char *buf)
571 if (desc->flags & _DPRINTK_FLAGS_INCL_TID) {
573 pos += snprintf(buf + pos, remaining(pos), "<intr> ");
575 pos += snprintf(buf + pos, remaining(pos), "[%d] ",
576 task_pid_vnr(current));
579 if (desc->flags & _DPRINTK_FLAGS_INCL_MODNAME)
580 pos += snprintf(buf + pos, remaining(pos), "%s:",
582 if (desc->flags & _DPRINTK_FLAGS_INCL_FUNCNAME)
583 pos += snprintf(buf + pos, remaining(pos), "%s:",
585 if (desc->flags & _DPRINTK_FLAGS_INCL_LINENO)
586 pos += snprintf(buf + pos, remaining(pos), "%d:",
588 if (pos - pos_after_tid)
589 pos += snprintf(buf + pos, remaining(pos), " ");
590 if (pos >= PREFIX_SIZE)
591 buf[PREFIX_SIZE - 1] = '\0';
596 void __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...)
599 struct va_format vaf;
600 char buf[PREFIX_SIZE];
610 printk(KERN_DEBUG "%s%pV", dynamic_emit_prefix(descriptor, buf), &vaf);
614 EXPORT_SYMBOL(__dynamic_pr_debug);
616 void __dynamic_dev_dbg(struct _ddebug *descriptor,
617 const struct device *dev, const char *fmt, ...)
619 struct va_format vaf;
631 printk(KERN_DEBUG "(NULL device *): %pV", &vaf);
633 char buf[PREFIX_SIZE];
635 dev_printk_emit(LOGLEVEL_DEBUG, dev, "%s%s %s: %pV",
636 dynamic_emit_prefix(descriptor, buf),
637 dev_driver_string(dev), dev_name(dev),
643 EXPORT_SYMBOL(__dynamic_dev_dbg);
647 void __dynamic_netdev_dbg(struct _ddebug *descriptor,
648 const struct net_device *dev, const char *fmt, ...)
650 struct va_format vaf;
661 if (dev && dev->dev.parent) {
662 char buf[PREFIX_SIZE];
664 dev_printk_emit(LOGLEVEL_DEBUG, dev->dev.parent,
666 dynamic_emit_prefix(descriptor, buf),
667 dev_driver_string(dev->dev.parent),
668 dev_name(dev->dev.parent),
669 netdev_name(dev), netdev_reg_state(dev),
672 printk(KERN_DEBUG "%s%s: %pV", netdev_name(dev),
673 netdev_reg_state(dev), &vaf);
675 printk(KERN_DEBUG "(NULL net_device): %pV", &vaf);
680 EXPORT_SYMBOL(__dynamic_netdev_dbg);
684 #if IS_ENABLED(CONFIG_INFINIBAND)
686 void __dynamic_ibdev_dbg(struct _ddebug *descriptor,
687 const struct ib_device *ibdev, const char *fmt, ...)
689 struct va_format vaf;
697 if (ibdev && ibdev->dev.parent) {
698 char buf[PREFIX_SIZE];
700 dev_printk_emit(LOGLEVEL_DEBUG, ibdev->dev.parent,
702 dynamic_emit_prefix(descriptor, buf),
703 dev_driver_string(ibdev->dev.parent),
704 dev_name(ibdev->dev.parent),
705 dev_name(&ibdev->dev),
708 printk(KERN_DEBUG "%s: %pV", dev_name(&ibdev->dev), &vaf);
710 printk(KERN_DEBUG "(NULL ib_device): %pV", &vaf);
715 EXPORT_SYMBOL(__dynamic_ibdev_dbg);
719 #define DDEBUG_STRING_SIZE 1024
720 static __initdata char ddebug_setup_string[DDEBUG_STRING_SIZE];
722 static __init int ddebug_setup_query(char *str)
724 if (strlen(str) >= DDEBUG_STRING_SIZE) {
725 pr_warn("ddebug boot param string too large\n");
728 strlcpy(ddebug_setup_string, str, DDEBUG_STRING_SIZE);
732 __setup("ddebug_query=", ddebug_setup_query);
735 * File_ops->write method for <debugfs>/dynamic_debug/control. Gathers the
736 * command text from userspace, parses and executes it.
738 #define USER_BUF_PAGE 4096
739 static ssize_t ddebug_proc_write(struct file *file, const char __user *ubuf,
740 size_t len, loff_t *offp)
747 if (len > USER_BUF_PAGE - 1) {
748 pr_warn("expected <%d bytes into control\n", USER_BUF_PAGE);
751 tmpbuf = memdup_user_nul(ubuf, len);
753 return PTR_ERR(tmpbuf);
754 vpr_info("read %d bytes from userspace\n", (int)len);
756 ret = ddebug_exec_queries(tmpbuf, NULL);
766 * Set the iterator to point to the first _ddebug object
767 * and return a pointer to that first object. Returns
768 * NULL if there are no _ddebugs at all.
770 static struct _ddebug *ddebug_iter_first(struct ddebug_iter *iter)
772 if (list_empty(&ddebug_tables)) {
777 iter->table = list_entry(ddebug_tables.next,
778 struct ddebug_table, link);
780 return &iter->table->ddebugs[iter->idx];
784 * Advance the iterator to point to the next _ddebug
785 * object from the one the iterator currently points at,
786 * and returns a pointer to the new _ddebug. Returns
787 * NULL if the iterator has seen all the _ddebugs.
789 static struct _ddebug *ddebug_iter_next(struct ddebug_iter *iter)
791 if (iter->table == NULL)
793 if (++iter->idx == iter->table->num_ddebugs) {
794 /* iterate to next table */
796 if (list_is_last(&iter->table->link, &ddebug_tables)) {
800 iter->table = list_entry(iter->table->link.next,
801 struct ddebug_table, link);
803 return &iter->table->ddebugs[iter->idx];
807 * Seq_ops start method. Called at the start of every
808 * read() call from userspace. Takes the ddebug_lock and
809 * seeks the seq_file's iterator to the given position.
811 static void *ddebug_proc_start(struct seq_file *m, loff_t *pos)
813 struct ddebug_iter *iter = m->private;
817 mutex_lock(&ddebug_lock);
820 return SEQ_START_TOKEN;
823 dp = ddebug_iter_first(iter);
824 while (dp != NULL && --n > 0)
825 dp = ddebug_iter_next(iter);
830 * Seq_ops next method. Called several times within a read()
831 * call from userspace, with ddebug_lock held. Walks to the
832 * next _ddebug object with a special case for the header line.
834 static void *ddebug_proc_next(struct seq_file *m, void *p, loff_t *pos)
836 struct ddebug_iter *iter = m->private;
839 if (p == SEQ_START_TOKEN)
840 dp = ddebug_iter_first(iter);
842 dp = ddebug_iter_next(iter);
848 * Seq_ops show method. Called several times within a read()
849 * call from userspace, with ddebug_lock held. Formats the
850 * current _ddebug as a single human-readable line, with a
851 * special case for the header line.
853 static int ddebug_proc_show(struct seq_file *m, void *p)
855 struct ddebug_iter *iter = m->private;
856 struct _ddebug *dp = p;
857 struct flagsbuf flags;
859 if (p == SEQ_START_TOKEN) {
861 "# filename:lineno [module]function flags format\n");
865 seq_printf(m, "%s:%u [%s]%s =%s \"",
866 trim_prefix(dp->filename), dp->lineno,
867 iter->table->mod_name, dp->function,
868 ddebug_describe_flags(dp->flags, &flags));
869 seq_escape(m, dp->format, "\t\r\n\"");
876 * Seq_ops stop method. Called at the end of each read()
877 * call from userspace. Drops ddebug_lock.
879 static void ddebug_proc_stop(struct seq_file *m, void *p)
881 mutex_unlock(&ddebug_lock);
884 static const struct seq_operations ddebug_proc_seqops = {
885 .start = ddebug_proc_start,
886 .next = ddebug_proc_next,
887 .show = ddebug_proc_show,
888 .stop = ddebug_proc_stop
891 static int ddebug_proc_open(struct inode *inode, struct file *file)
893 vpr_info("called\n");
894 return seq_open_private(file, &ddebug_proc_seqops,
895 sizeof(struct ddebug_iter));
898 static const struct file_operations ddebug_proc_fops = {
899 .owner = THIS_MODULE,
900 .open = ddebug_proc_open,
903 .release = seq_release_private,
904 .write = ddebug_proc_write
907 static const struct proc_ops proc_fops = {
908 .proc_open = ddebug_proc_open,
909 .proc_read = seq_read,
910 .proc_lseek = seq_lseek,
911 .proc_release = seq_release_private,
912 .proc_write = ddebug_proc_write
916 * Allocate a new ddebug_table for the given module
917 * and add it to the global list.
919 int ddebug_add_module(struct _ddebug *tab, unsigned int n,
922 struct ddebug_table *dt;
924 dt = kzalloc(sizeof(*dt), GFP_KERNEL);
926 pr_err("error adding module: %s\n", name);
930 * For built-in modules, name lives in .rodata and is
931 * immortal. For loaded modules, name points at the name[]
932 * member of struct module, which lives at least as long as
933 * this struct ddebug_table.
939 mutex_lock(&ddebug_lock);
940 list_add(&dt->link, &ddebug_tables);
941 mutex_unlock(&ddebug_lock);
943 v2pr_info("%3u debug prints in module %s\n", n, dt->mod_name);
947 /* helper for ddebug_dyndbg_(boot|module)_param_cb */
948 static int ddebug_dyndbg_param_cb(char *param, char *val,
949 const char *modname, int on_err)
953 sep = strchr(param, '.');
955 /* needed only for ddebug_dyndbg_boot_param_cb */
960 if (strcmp(param, "dyndbg"))
961 return on_err; /* determined by caller */
963 ddebug_exec_queries((val ? val : "+p"), modname);
965 return 0; /* query failure shouldnt stop module load */
968 /* handle both dyndbg and $module.dyndbg params at boot */
969 static int ddebug_dyndbg_boot_param_cb(char *param, char *val,
970 const char *unused, void *arg)
972 vpr_info("%s=\"%s\"\n", param, val);
973 return ddebug_dyndbg_param_cb(param, val, NULL, 0);
977 * modprobe foo finds foo.params in boot-args, strips "foo.", and
978 * passes them to load_module(). This callback gets unknown params,
979 * processes dyndbg params, rejects others.
981 int ddebug_dyndbg_module_param_cb(char *param, char *val, const char *module)
983 vpr_info("module: %s %s=\"%s\"\n", module, param, val);
984 return ddebug_dyndbg_param_cb(param, val, module, -ENOENT);
987 static void ddebug_table_free(struct ddebug_table *dt)
989 list_del_init(&dt->link);
994 * Called in response to a module being unloaded. Removes
995 * any ddebug_table's which point at the module.
997 int ddebug_remove_module(const char *mod_name)
999 struct ddebug_table *dt, *nextdt;
1002 v2pr_info("removing module \"%s\"\n", mod_name);
1004 mutex_lock(&ddebug_lock);
1005 list_for_each_entry_safe(dt, nextdt, &ddebug_tables, link) {
1006 if (dt->mod_name == mod_name) {
1007 ddebug_table_free(dt);
1012 mutex_unlock(&ddebug_lock);
1016 static void ddebug_remove_all_tables(void)
1018 mutex_lock(&ddebug_lock);
1019 while (!list_empty(&ddebug_tables)) {
1020 struct ddebug_table *dt = list_entry(ddebug_tables.next,
1021 struct ddebug_table,
1023 ddebug_table_free(dt);
1025 mutex_unlock(&ddebug_lock);
1028 static __initdata int ddebug_init_success;
1030 static int __init dynamic_debug_init_control(void)
1032 struct proc_dir_entry *procfs_dir;
1033 struct dentry *debugfs_dir;
1035 if (!ddebug_init_success)
1038 /* Create the control file in debugfs if it is enabled */
1039 if (debugfs_initialized()) {
1040 debugfs_dir = debugfs_create_dir("dynamic_debug", NULL);
1041 debugfs_create_file("control", 0644, debugfs_dir, NULL,
1045 /* Also create the control file in procfs */
1046 procfs_dir = proc_mkdir("dynamic_debug", NULL);
1048 proc_create("control", 0644, procfs_dir, &proc_fops);
1053 static int __init dynamic_debug_init(void)
1055 struct _ddebug *iter, *iter_start;
1056 const char *modname = NULL;
1059 int n = 0, entries = 0, modct = 0;
1061 if (&__start___dyndbg == &__stop___dyndbg) {
1062 if (IS_ENABLED(CONFIG_DYNAMIC_DEBUG)) {
1063 pr_warn("_ddebug table is empty in a CONFIG_DYNAMIC_DEBUG build\n");
1066 pr_info("Ignore empty _ddebug table in a CONFIG_DYNAMIC_DEBUG_CORE build\n");
1067 ddebug_init_success = 1;
1070 iter = __start___dyndbg;
1071 modname = iter->modname;
1073 for (; iter < __stop___dyndbg; iter++) {
1075 if (strcmp(modname, iter->modname)) {
1077 ret = ddebug_add_module(iter_start, n, modname);
1081 modname = iter->modname;
1086 ret = ddebug_add_module(iter_start, n, modname);
1090 ddebug_init_success = 1;
1091 vpr_info("%d modules, %d entries and %d bytes in ddebug tables, %d bytes in __dyndbg section\n",
1092 modct, entries, (int)(modct * sizeof(struct ddebug_table)),
1093 (int)(entries * sizeof(struct _ddebug)));
1095 /* apply ddebug_query boot param, dont unload tables on err */
1096 if (ddebug_setup_string[0] != '\0') {
1097 pr_warn("ddebug_query param name is deprecated, change it to dyndbg\n");
1098 ret = ddebug_exec_queries(ddebug_setup_string, NULL);
1100 pr_warn("Invalid ddebug boot param %s\n",
1101 ddebug_setup_string);
1103 pr_info("%d changes by ddebug_query\n", ret);
1105 /* now that ddebug tables are loaded, process all boot args
1106 * again to find and activate queries given in dyndbg params.
1107 * While this has already been done for known boot params, it
1108 * ignored the unknown ones (dyndbg in particular). Reusing
1109 * parse_args avoids ad-hoc parsing. This will also attempt
1110 * to activate queries for not-yet-loaded modules, which is
1111 * slightly noisy if verbose, but harmless.
1113 cmdline = kstrdup(saved_command_line, GFP_KERNEL);
1114 parse_args("dyndbg params", cmdline, NULL,
1115 0, 0, 0, NULL, &ddebug_dyndbg_boot_param_cb);
1120 ddebug_remove_all_tables();
1123 /* Allow early initialization for boot messages via boot param */
1124 early_initcall(dynamic_debug_init);
1126 /* Debugfs setup must be done later */
1127 fs_initcall(dynamic_debug_init_control);