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 (!(modifiers->flags & _DPRINTK_FLAGS_PRINT))
211 static_branch_disable(&dp->key.dd_key_true);
212 } else if (modifiers->flags & _DPRINTK_FLAGS_PRINT)
213 static_branch_enable(&dp->key.dd_key_true);
215 dp->flags = newflags;
216 v2pr_info("changed %s:%d [%s]%s =%s\n",
217 trim_prefix(dp->filename), dp->lineno,
218 dt->mod_name, dp->function,
219 ddebug_describe_flags(dp->flags, &fbuf));
222 mutex_unlock(&ddebug_lock);
224 if (!nfound && verbose)
225 pr_info("no matches for query\n");
231 * Split the buffer `buf' into space-separated words.
232 * Handles simple " and ' quoting, i.e. without nested,
233 * embedded or escaped \". Return the number of words
236 static int ddebug_tokenize(char *buf, char *words[], int maxwords)
243 /* Skip leading whitespace */
244 buf = skip_spaces(buf);
246 break; /* oh, it was trailing whitespace */
248 break; /* token starts comment, skip rest of line */
250 /* find `end' of word, whitespace separated or quoted */
251 if (*buf == '"' || *buf == '\'') {
253 for (end = buf; *end && *end != quote; end++)
256 pr_err("unclosed quote: %s\n", buf);
257 return -EINVAL; /* unclosed quote */
260 for (end = buf; *end && !isspace(*end); end++)
265 /* `buf' is start of word, `end' is one past its end */
266 if (nwords == maxwords) {
267 pr_err("too many words, legal max <=%d\n", maxwords);
268 return -EINVAL; /* ran out of words[] before bytes */
271 *end++ = '\0'; /* terminate the word */
272 words[nwords++] = buf;
278 pr_info("split into words:");
279 for (i = 0; i < nwords; i++)
280 pr_cont(" \"%s\"", words[i]);
288 * Parse a single line number. Note that the empty string ""
289 * is treated as a special case and converted to zero, which
290 * is later treated as a "don't care" value.
292 static inline int parse_lineno(const char *str, unsigned int *val)
299 if (kstrtouint(str, 10, val) < 0) {
300 pr_err("bad line-number: %s\n", str);
306 static int parse_linerange(struct ddebug_query *query, const char *first)
308 char *last = strchr(first, '-');
310 if (query->first_lineno || query->last_lineno) {
311 pr_err("match-spec: line used 2x\n");
316 if (parse_lineno(first, &query->first_lineno) < 0)
319 /* range <first>-<last> */
320 if (parse_lineno(last, &query->last_lineno) < 0)
323 /* special case for last lineno not specified */
324 if (query->last_lineno == 0)
325 query->last_lineno = UINT_MAX;
327 if (query->last_lineno < query->first_lineno) {
328 pr_err("last-line:%d < 1st-line:%d\n",
330 query->first_lineno);
334 query->last_lineno = query->first_lineno;
336 vpr_info("parsed line %d-%d\n", query->first_lineno,
341 static int check_set(const char **dest, char *src, char *name)
347 pr_err("match-spec:%s val:%s overridden by %s\n",
355 * Parse words[] as a ddebug query specification, which is a series
356 * of (keyword, value) pairs or combined keyword=value terms,
357 * 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)
379 /* support $modname.dyndbg=<multiple queries> */
380 query->module = modname;
382 for (i = 0; i < nwords; i++) {
383 /* accept keyword=arg */
384 vpr_info("%d w:%s\n", i, words[i]);
387 arg = strchr(keyword, '=');
391 i++; /* next word is arg */
393 pr_err("missing arg to keyword: %s\n", keyword);
398 vpr_info("%d key:%s arg:%s\n", i, keyword, arg);
400 if (!strcmp(keyword, "func")) {
401 rc = check_set(&query->function, arg, "func");
402 } else if (!strcmp(keyword, "file")) {
403 if (check_set(&query->filename, arg, "file"))
406 /* tail :$info is function or line-range */
407 fline = strchr(query->filename, ':');
411 if (isalpha(*fline) || *fline == '*' || *fline == '?') {
412 /* take as function name */
413 if (check_set(&query->function, fline, "func"))
416 if (parse_linerange(query, fline))
419 } else if (!strcmp(keyword, "module")) {
420 rc = check_set(&query->module, arg, "module");
421 } else if (!strcmp(keyword, "format")) {
422 string_unescape_inplace(arg, UNESCAPE_SPACE |
425 rc = check_set(&query->format, arg, "format");
426 } else if (!strcmp(keyword, "line")) {
427 if (parse_linerange(query, arg))
430 pr_err("unknown keyword \"%s\"\n", keyword);
436 vpr_info_dq(query, "parsed");
441 * Parse `str' as a flags specification, format [-+=][p]+.
442 * Sets up *maskp and *flagsp to be used when changing the
443 * flags fields of matched _ddebug's. Returns 0 on success
446 static int ddebug_parse_flags(const char *str, struct flag_settings *modifiers)
457 pr_err("bad flag-op %c, at start of %s\n", *str, str);
460 vpr_info("op='%c'\n", op);
462 for (; *str ; ++str) {
463 for (i = ARRAY_SIZE(opt_array) - 1; i >= 0; i--) {
464 if (*str == opt_array[i].opt_char) {
465 modifiers->flags |= opt_array[i].flag;
470 pr_err("unknown flag '%c'\n", *str);
474 vpr_info("flags=0x%x\n", modifiers->flags);
476 /* calculate final flags, mask based upon op */
479 /* modifiers->flags already set */
483 modifiers->mask = ~0U;
486 modifiers->mask = ~modifiers->flags;
487 modifiers->flags = 0;
490 vpr_info("*flagsp=0x%x *maskp=0x%x\n", modifiers->flags, modifiers->mask);
495 static int ddebug_exec_query(char *query_string, const char *modname)
497 struct flag_settings modifiers = {};
498 struct ddebug_query query = {};
501 char *words[MAXWORDS];
503 nwords = ddebug_tokenize(query_string, words, MAXWORDS);
505 pr_err("tokenize failed\n");
508 /* check flags 1st (last arg) so query is pairs of spec,val */
509 if (ddebug_parse_flags(words[nwords-1], &modifiers)) {
510 pr_err("flags parse failed\n");
513 if (ddebug_parse_query(words, nwords-1, &query, modname)) {
514 pr_err("query parse failed\n");
517 /* actually go and implement the change */
518 nfound = ddebug_change(&query, &modifiers);
519 vpr_info_dq(&query, nfound ? "applied" : "no-match");
524 /* handle multiple queries in query string, continue on error, return
525 last error or number of matching callsites. Module name is either
526 in param (for boot arg) or perhaps in query string.
528 int ddebug_exec_queries(char *query, const char *modname)
531 int i, errs = 0, exitcode = 0, rc, nfound = 0;
533 for (i = 0; query; query = split) {
534 split = strpbrk(query, ";\n");
538 query = skip_spaces(query);
539 if (!query || !*query || *query == '#')
542 vpr_info("query %d: \"%s\"\n", i, query);
544 rc = ddebug_exec_query(query, modname);
553 vpr_info("processed %d queries, with %d matches, %d errs\n",
560 EXPORT_SYMBOL_GPL(ddebug_exec_queries);
562 #define PREFIX_SIZE 64
564 static int remaining(int wrote)
566 if (PREFIX_SIZE - wrote > 0)
567 return PREFIX_SIZE - wrote;
571 static char *dynamic_emit_prefix(const struct _ddebug *desc, char *buf)
578 if (desc->flags & _DPRINTK_FLAGS_INCL_TID) {
580 pos += snprintf(buf + pos, remaining(pos), "<intr> ");
582 pos += snprintf(buf + pos, remaining(pos), "[%d] ",
583 task_pid_vnr(current));
586 if (desc->flags & _DPRINTK_FLAGS_INCL_MODNAME)
587 pos += snprintf(buf + pos, remaining(pos), "%s:",
589 if (desc->flags & _DPRINTK_FLAGS_INCL_FUNCNAME)
590 pos += snprintf(buf + pos, remaining(pos), "%s:",
592 if (desc->flags & _DPRINTK_FLAGS_INCL_LINENO)
593 pos += snprintf(buf + pos, remaining(pos), "%d:",
595 if (pos - pos_after_tid)
596 pos += snprintf(buf + pos, remaining(pos), " ");
597 if (pos >= PREFIX_SIZE)
598 buf[PREFIX_SIZE - 1] = '\0';
603 void __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...)
606 struct va_format vaf;
607 char buf[PREFIX_SIZE];
617 printk(KERN_DEBUG "%s%pV", dynamic_emit_prefix(descriptor, buf), &vaf);
621 EXPORT_SYMBOL(__dynamic_pr_debug);
623 void __dynamic_dev_dbg(struct _ddebug *descriptor,
624 const struct device *dev, const char *fmt, ...)
626 struct va_format vaf;
638 printk(KERN_DEBUG "(NULL device *): %pV", &vaf);
640 char buf[PREFIX_SIZE];
642 dev_printk_emit(LOGLEVEL_DEBUG, dev, "%s%s %s: %pV",
643 dynamic_emit_prefix(descriptor, buf),
644 dev_driver_string(dev), dev_name(dev),
650 EXPORT_SYMBOL(__dynamic_dev_dbg);
654 void __dynamic_netdev_dbg(struct _ddebug *descriptor,
655 const struct net_device *dev, const char *fmt, ...)
657 struct va_format vaf;
668 if (dev && dev->dev.parent) {
669 char buf[PREFIX_SIZE];
671 dev_printk_emit(LOGLEVEL_DEBUG, dev->dev.parent,
673 dynamic_emit_prefix(descriptor, buf),
674 dev_driver_string(dev->dev.parent),
675 dev_name(dev->dev.parent),
676 netdev_name(dev), netdev_reg_state(dev),
679 printk(KERN_DEBUG "%s%s: %pV", netdev_name(dev),
680 netdev_reg_state(dev), &vaf);
682 printk(KERN_DEBUG "(NULL net_device): %pV", &vaf);
687 EXPORT_SYMBOL(__dynamic_netdev_dbg);
691 #if IS_ENABLED(CONFIG_INFINIBAND)
693 void __dynamic_ibdev_dbg(struct _ddebug *descriptor,
694 const struct ib_device *ibdev, const char *fmt, ...)
696 struct va_format vaf;
704 if (ibdev && ibdev->dev.parent) {
705 char buf[PREFIX_SIZE];
707 dev_printk_emit(LOGLEVEL_DEBUG, ibdev->dev.parent,
709 dynamic_emit_prefix(descriptor, buf),
710 dev_driver_string(ibdev->dev.parent),
711 dev_name(ibdev->dev.parent),
712 dev_name(&ibdev->dev),
715 printk(KERN_DEBUG "%s: %pV", dev_name(&ibdev->dev), &vaf);
717 printk(KERN_DEBUG "(NULL ib_device): %pV", &vaf);
722 EXPORT_SYMBOL(__dynamic_ibdev_dbg);
726 #define DDEBUG_STRING_SIZE 1024
727 static __initdata char ddebug_setup_string[DDEBUG_STRING_SIZE];
729 static __init int ddebug_setup_query(char *str)
731 if (strlen(str) >= DDEBUG_STRING_SIZE) {
732 pr_warn("ddebug boot param string too large\n");
735 strlcpy(ddebug_setup_string, str, DDEBUG_STRING_SIZE);
739 __setup("ddebug_query=", ddebug_setup_query);
742 * File_ops->write method for <debugfs>/dynamic_debug/control. Gathers the
743 * command text from userspace, parses and executes it.
745 #define USER_BUF_PAGE 4096
746 static ssize_t ddebug_proc_write(struct file *file, const char __user *ubuf,
747 size_t len, loff_t *offp)
754 if (len > USER_BUF_PAGE - 1) {
755 pr_warn("expected <%d bytes into control\n", USER_BUF_PAGE);
758 tmpbuf = memdup_user_nul(ubuf, len);
760 return PTR_ERR(tmpbuf);
761 vpr_info("read %d bytes from userspace\n", (int)len);
763 ret = ddebug_exec_queries(tmpbuf, NULL);
773 * Set the iterator to point to the first _ddebug object
774 * and return a pointer to that first object. Returns
775 * NULL if there are no _ddebugs at all.
777 static struct _ddebug *ddebug_iter_first(struct ddebug_iter *iter)
779 if (list_empty(&ddebug_tables)) {
784 iter->table = list_entry(ddebug_tables.next,
785 struct ddebug_table, link);
787 return &iter->table->ddebugs[iter->idx];
791 * Advance the iterator to point to the next _ddebug
792 * object from the one the iterator currently points at,
793 * and returns a pointer to the new _ddebug. Returns
794 * NULL if the iterator has seen all the _ddebugs.
796 static struct _ddebug *ddebug_iter_next(struct ddebug_iter *iter)
798 if (iter->table == NULL)
800 if (++iter->idx == iter->table->num_ddebugs) {
801 /* iterate to next table */
803 if (list_is_last(&iter->table->link, &ddebug_tables)) {
807 iter->table = list_entry(iter->table->link.next,
808 struct ddebug_table, link);
810 return &iter->table->ddebugs[iter->idx];
814 * Seq_ops start method. Called at the start of every
815 * read() call from userspace. Takes the ddebug_lock and
816 * seeks the seq_file's iterator to the given position.
818 static void *ddebug_proc_start(struct seq_file *m, loff_t *pos)
820 struct ddebug_iter *iter = m->private;
824 mutex_lock(&ddebug_lock);
827 return SEQ_START_TOKEN;
830 dp = ddebug_iter_first(iter);
831 while (dp != NULL && --n > 0)
832 dp = ddebug_iter_next(iter);
837 * Seq_ops next method. Called several times within a read()
838 * call from userspace, with ddebug_lock held. Walks to the
839 * next _ddebug object with a special case for the header line.
841 static void *ddebug_proc_next(struct seq_file *m, void *p, loff_t *pos)
843 struct ddebug_iter *iter = m->private;
846 if (p == SEQ_START_TOKEN)
847 dp = ddebug_iter_first(iter);
849 dp = ddebug_iter_next(iter);
855 * Seq_ops show method. Called several times within a read()
856 * call from userspace, with ddebug_lock held. Formats the
857 * current _ddebug as a single human-readable line, with a
858 * special case for the header line.
860 static int ddebug_proc_show(struct seq_file *m, void *p)
862 struct ddebug_iter *iter = m->private;
863 struct _ddebug *dp = p;
864 struct flagsbuf flags;
866 if (p == SEQ_START_TOKEN) {
868 "# filename:lineno [module]function flags format\n");
872 seq_printf(m, "%s:%u [%s]%s =%s \"",
873 trim_prefix(dp->filename), dp->lineno,
874 iter->table->mod_name, dp->function,
875 ddebug_describe_flags(dp->flags, &flags));
876 seq_escape(m, dp->format, "\t\r\n\"");
883 * Seq_ops stop method. Called at the end of each read()
884 * call from userspace. Drops ddebug_lock.
886 static void ddebug_proc_stop(struct seq_file *m, void *p)
888 mutex_unlock(&ddebug_lock);
891 static const struct seq_operations ddebug_proc_seqops = {
892 .start = ddebug_proc_start,
893 .next = ddebug_proc_next,
894 .show = ddebug_proc_show,
895 .stop = ddebug_proc_stop
898 static int ddebug_proc_open(struct inode *inode, struct file *file)
900 vpr_info("called\n");
901 return seq_open_private(file, &ddebug_proc_seqops,
902 sizeof(struct ddebug_iter));
905 static const struct file_operations ddebug_proc_fops = {
906 .owner = THIS_MODULE,
907 .open = ddebug_proc_open,
910 .release = seq_release_private,
911 .write = ddebug_proc_write
914 static const struct proc_ops proc_fops = {
915 .proc_open = ddebug_proc_open,
916 .proc_read = seq_read,
917 .proc_lseek = seq_lseek,
918 .proc_release = seq_release_private,
919 .proc_write = ddebug_proc_write
923 * Allocate a new ddebug_table for the given module
924 * and add it to the global list.
926 int ddebug_add_module(struct _ddebug *tab, unsigned int n,
929 struct ddebug_table *dt;
931 dt = kzalloc(sizeof(*dt), GFP_KERNEL);
933 pr_err("error adding module: %s\n", name);
937 * For built-in modules, name lives in .rodata and is
938 * immortal. For loaded modules, name points at the name[]
939 * member of struct module, which lives at least as long as
940 * this struct ddebug_table.
946 mutex_lock(&ddebug_lock);
947 list_add(&dt->link, &ddebug_tables);
948 mutex_unlock(&ddebug_lock);
950 v2pr_info("%u debug prints in module %s\n", n, dt->mod_name);
954 /* helper for ddebug_dyndbg_(boot|module)_param_cb */
955 static int ddebug_dyndbg_param_cb(char *param, char *val,
956 const char *modname, int on_err)
960 sep = strchr(param, '.');
962 /* needed only for ddebug_dyndbg_boot_param_cb */
967 if (strcmp(param, "dyndbg"))
968 return on_err; /* determined by caller */
970 ddebug_exec_queries((val ? val : "+p"), modname);
972 return 0; /* query failure shouldnt stop module load */
975 /* handle both dyndbg and $module.dyndbg params at boot */
976 static int ddebug_dyndbg_boot_param_cb(char *param, char *val,
977 const char *unused, void *arg)
979 vpr_info("%s=\"%s\"\n", param, val);
980 return ddebug_dyndbg_param_cb(param, val, NULL, 0);
984 * modprobe foo finds foo.params in boot-args, strips "foo.", and
985 * passes them to load_module(). This callback gets unknown params,
986 * processes dyndbg params, rejects others.
988 int ddebug_dyndbg_module_param_cb(char *param, char *val, const char *module)
990 vpr_info("module: %s %s=\"%s\"\n", module, param, val);
991 return ddebug_dyndbg_param_cb(param, val, module, -ENOENT);
994 static void ddebug_table_free(struct ddebug_table *dt)
996 list_del_init(&dt->link);
1001 * Called in response to a module being unloaded. Removes
1002 * any ddebug_table's which point at the module.
1004 int ddebug_remove_module(const char *mod_name)
1006 struct ddebug_table *dt, *nextdt;
1009 v2pr_info("removing module \"%s\"\n", mod_name);
1011 mutex_lock(&ddebug_lock);
1012 list_for_each_entry_safe(dt, nextdt, &ddebug_tables, link) {
1013 if (dt->mod_name == mod_name) {
1014 ddebug_table_free(dt);
1019 mutex_unlock(&ddebug_lock);
1023 static void ddebug_remove_all_tables(void)
1025 mutex_lock(&ddebug_lock);
1026 while (!list_empty(&ddebug_tables)) {
1027 struct ddebug_table *dt = list_entry(ddebug_tables.next,
1028 struct ddebug_table,
1030 ddebug_table_free(dt);
1032 mutex_unlock(&ddebug_lock);
1035 static __initdata int ddebug_init_success;
1037 static int __init dynamic_debug_init_control(void)
1039 struct proc_dir_entry *procfs_dir;
1040 struct dentry *debugfs_dir;
1042 if (!ddebug_init_success)
1045 /* Create the control file in debugfs if it is enabled */
1046 if (debugfs_initialized()) {
1047 debugfs_dir = debugfs_create_dir("dynamic_debug", NULL);
1048 debugfs_create_file("control", 0644, debugfs_dir, NULL,
1052 /* Also create the control file in procfs */
1053 procfs_dir = proc_mkdir("dynamic_debug", NULL);
1055 proc_create("control", 0644, procfs_dir, &proc_fops);
1060 static int __init dynamic_debug_init(void)
1062 struct _ddebug *iter, *iter_start;
1063 const char *modname = NULL;
1066 int n = 0, entries = 0, modct = 0;
1068 if (&__start___dyndbg == &__stop___dyndbg) {
1069 if (IS_ENABLED(CONFIG_DYNAMIC_DEBUG)) {
1070 pr_warn("_ddebug table is empty in a CONFIG_DYNAMIC_DEBUG build\n");
1073 pr_info("Ignore empty _ddebug table in a CONFIG_DYNAMIC_DEBUG_CORE build\n");
1074 ddebug_init_success = 1;
1077 iter = __start___dyndbg;
1078 modname = iter->modname;
1080 for (; iter < __stop___dyndbg; iter++) {
1082 if (strcmp(modname, iter->modname)) {
1084 ret = ddebug_add_module(iter_start, n, modname);
1088 modname = iter->modname;
1093 ret = ddebug_add_module(iter_start, n, modname);
1097 ddebug_init_success = 1;
1098 vpr_info("%d modules, %d entries and %d bytes in ddebug tables, %d bytes in __dyndbg section\n",
1099 modct, entries, (int)(modct * sizeof(struct ddebug_table)),
1100 (int)(entries * sizeof(struct _ddebug)));
1102 /* apply ddebug_query boot param, dont unload tables on err */
1103 if (ddebug_setup_string[0] != '\0') {
1104 pr_warn("ddebug_query param name is deprecated, change it to dyndbg\n");
1105 ret = ddebug_exec_queries(ddebug_setup_string, NULL);
1107 pr_warn("Invalid ddebug boot param %s\n",
1108 ddebug_setup_string);
1110 pr_info("%d changes by ddebug_query\n", ret);
1112 /* now that ddebug tables are loaded, process all boot args
1113 * again to find and activate queries given in dyndbg params.
1114 * While this has already been done for known boot params, it
1115 * ignored the unknown ones (dyndbg in particular). Reusing
1116 * parse_args avoids ad-hoc parsing. This will also attempt
1117 * to activate queries for not-yet-loaded modules, which is
1118 * slightly noisy if verbose, but harmless.
1120 cmdline = kstrdup(saved_command_line, GFP_KERNEL);
1121 parse_args("dyndbg params", cmdline, NULL,
1122 0, 0, 0, NULL, &ddebug_dyndbg_boot_param_cb);
1127 ddebug_remove_all_tables();
1130 /* Allow early initialization for boot messages via boot param */
1131 early_initcall(dynamic_debug_init);
1133 /* Debugfs setup must be done later */
1134 fs_initcall(dynamic_debug_init_control);