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)
569 if (desc->flags & _DPRINTK_FLAGS_INCL_TID) {
571 pos += snprintf(buf + pos, remaining(pos), "<intr> ");
573 pos += snprintf(buf + pos, remaining(pos), "[%d] ",
574 task_pid_vnr(current));
577 if (desc->flags & _DPRINTK_FLAGS_INCL_MODNAME)
578 pos += snprintf(buf + pos, remaining(pos), "%s:",
580 if (desc->flags & _DPRINTK_FLAGS_INCL_FUNCNAME)
581 pos += snprintf(buf + pos, remaining(pos), "%s:",
583 if (desc->flags & _DPRINTK_FLAGS_INCL_LINENO)
584 pos += snprintf(buf + pos, remaining(pos), "%d:",
586 if (pos - pos_after_tid)
587 pos += snprintf(buf + pos, remaining(pos), " ");
588 if (pos >= PREFIX_SIZE)
589 buf[PREFIX_SIZE - 1] = '\0';
594 static inline char *dynamic_emit_prefix(struct _ddebug *desc, char *buf)
596 if (unlikely(desc->flags & _DPRINTK_FLAGS_INCL_ANY))
597 return __dynamic_emit_prefix(desc, buf);
601 void __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...)
604 struct va_format vaf;
605 char buf[PREFIX_SIZE] = "";
615 printk(KERN_DEBUG "%s%pV", dynamic_emit_prefix(descriptor, buf), &vaf);
619 EXPORT_SYMBOL(__dynamic_pr_debug);
621 void __dynamic_dev_dbg(struct _ddebug *descriptor,
622 const struct device *dev, const char *fmt, ...)
624 struct va_format vaf;
636 printk(KERN_DEBUG "(NULL device *): %pV", &vaf);
638 char buf[PREFIX_SIZE] = "";
640 dev_printk_emit(LOGLEVEL_DEBUG, dev, "%s%s %s: %pV",
641 dynamic_emit_prefix(descriptor, buf),
642 dev_driver_string(dev), dev_name(dev),
648 EXPORT_SYMBOL(__dynamic_dev_dbg);
652 void __dynamic_netdev_dbg(struct _ddebug *descriptor,
653 const struct net_device *dev, const char *fmt, ...)
655 struct va_format vaf;
666 if (dev && dev->dev.parent) {
667 char buf[PREFIX_SIZE] = "";
669 dev_printk_emit(LOGLEVEL_DEBUG, dev->dev.parent,
671 dynamic_emit_prefix(descriptor, buf),
672 dev_driver_string(dev->dev.parent),
673 dev_name(dev->dev.parent),
674 netdev_name(dev), netdev_reg_state(dev),
677 printk(KERN_DEBUG "%s%s: %pV", netdev_name(dev),
678 netdev_reg_state(dev), &vaf);
680 printk(KERN_DEBUG "(NULL net_device): %pV", &vaf);
685 EXPORT_SYMBOL(__dynamic_netdev_dbg);
689 #if IS_ENABLED(CONFIG_INFINIBAND)
691 void __dynamic_ibdev_dbg(struct _ddebug *descriptor,
692 const struct ib_device *ibdev, const char *fmt, ...)
694 struct va_format vaf;
702 if (ibdev && ibdev->dev.parent) {
703 char buf[PREFIX_SIZE] = "";
705 dev_printk_emit(LOGLEVEL_DEBUG, ibdev->dev.parent,
707 dynamic_emit_prefix(descriptor, buf),
708 dev_driver_string(ibdev->dev.parent),
709 dev_name(ibdev->dev.parent),
710 dev_name(&ibdev->dev),
713 printk(KERN_DEBUG "%s: %pV", dev_name(&ibdev->dev), &vaf);
715 printk(KERN_DEBUG "(NULL ib_device): %pV", &vaf);
720 EXPORT_SYMBOL(__dynamic_ibdev_dbg);
724 #define DDEBUG_STRING_SIZE 1024
725 static __initdata char ddebug_setup_string[DDEBUG_STRING_SIZE];
727 static __init int ddebug_setup_query(char *str)
729 if (strlen(str) >= DDEBUG_STRING_SIZE) {
730 pr_warn("ddebug boot param string too large\n");
733 strlcpy(ddebug_setup_string, str, DDEBUG_STRING_SIZE);
737 __setup("ddebug_query=", ddebug_setup_query);
740 * Install a noop handler to make dyndbg look like a normal kernel cli param.
741 * This avoids warnings about dyndbg being an unknown cli param when supplied
744 static __init int dyndbg_setup(char *str)
749 __setup("dyndbg=", dyndbg_setup);
752 * File_ops->write method for <debugfs>/dynamic_debug/control. Gathers the
753 * command text from userspace, parses and executes it.
755 #define USER_BUF_PAGE 4096
756 static ssize_t ddebug_proc_write(struct file *file, const char __user *ubuf,
757 size_t len, loff_t *offp)
764 if (len > USER_BUF_PAGE - 1) {
765 pr_warn("expected <%d bytes into control\n", USER_BUF_PAGE);
768 tmpbuf = memdup_user_nul(ubuf, len);
770 return PTR_ERR(tmpbuf);
771 vpr_info("read %d bytes from userspace\n", (int)len);
773 ret = ddebug_exec_queries(tmpbuf, NULL);
783 * Set the iterator to point to the first _ddebug object
784 * and return a pointer to that first object. Returns
785 * NULL if there are no _ddebugs at all.
787 static struct _ddebug *ddebug_iter_first(struct ddebug_iter *iter)
789 if (list_empty(&ddebug_tables)) {
794 iter->table = list_entry(ddebug_tables.next,
795 struct ddebug_table, link);
797 return &iter->table->ddebugs[iter->idx];
801 * Advance the iterator to point to the next _ddebug
802 * object from the one the iterator currently points at,
803 * and returns a pointer to the new _ddebug. Returns
804 * NULL if the iterator has seen all the _ddebugs.
806 static struct _ddebug *ddebug_iter_next(struct ddebug_iter *iter)
808 if (iter->table == NULL)
810 if (++iter->idx == iter->table->num_ddebugs) {
811 /* iterate to next table */
813 if (list_is_last(&iter->table->link, &ddebug_tables)) {
817 iter->table = list_entry(iter->table->link.next,
818 struct ddebug_table, link);
820 return &iter->table->ddebugs[iter->idx];
824 * Seq_ops start method. Called at the start of every
825 * read() call from userspace. Takes the ddebug_lock and
826 * seeks the seq_file's iterator to the given position.
828 static void *ddebug_proc_start(struct seq_file *m, loff_t *pos)
830 struct ddebug_iter *iter = m->private;
834 mutex_lock(&ddebug_lock);
837 return SEQ_START_TOKEN;
840 dp = ddebug_iter_first(iter);
841 while (dp != NULL && --n > 0)
842 dp = ddebug_iter_next(iter);
847 * Seq_ops next method. Called several times within a read()
848 * call from userspace, with ddebug_lock held. Walks to the
849 * next _ddebug object with a special case for the header line.
851 static void *ddebug_proc_next(struct seq_file *m, void *p, loff_t *pos)
853 struct ddebug_iter *iter = m->private;
856 if (p == SEQ_START_TOKEN)
857 dp = ddebug_iter_first(iter);
859 dp = ddebug_iter_next(iter);
865 * Seq_ops show method. Called several times within a read()
866 * call from userspace, with ddebug_lock held. Formats the
867 * current _ddebug as a single human-readable line, with a
868 * special case for the header line.
870 static int ddebug_proc_show(struct seq_file *m, void *p)
872 struct ddebug_iter *iter = m->private;
873 struct _ddebug *dp = p;
874 struct flagsbuf flags;
876 if (p == SEQ_START_TOKEN) {
878 "# filename:lineno [module]function flags format\n");
882 seq_printf(m, "%s:%u [%s]%s =%s \"",
883 trim_prefix(dp->filename), dp->lineno,
884 iter->table->mod_name, dp->function,
885 ddebug_describe_flags(dp->flags, &flags));
886 seq_escape(m, dp->format, "\t\r\n\"");
893 * Seq_ops stop method. Called at the end of each read()
894 * call from userspace. Drops ddebug_lock.
896 static void ddebug_proc_stop(struct seq_file *m, void *p)
898 mutex_unlock(&ddebug_lock);
901 static const struct seq_operations ddebug_proc_seqops = {
902 .start = ddebug_proc_start,
903 .next = ddebug_proc_next,
904 .show = ddebug_proc_show,
905 .stop = ddebug_proc_stop
908 static int ddebug_proc_open(struct inode *inode, struct file *file)
910 return seq_open_private(file, &ddebug_proc_seqops,
911 sizeof(struct ddebug_iter));
914 static const struct file_operations ddebug_proc_fops = {
915 .owner = THIS_MODULE,
916 .open = ddebug_proc_open,
919 .release = seq_release_private,
920 .write = ddebug_proc_write
923 static const struct proc_ops proc_fops = {
924 .proc_open = ddebug_proc_open,
925 .proc_read = seq_read,
926 .proc_lseek = seq_lseek,
927 .proc_release = seq_release_private,
928 .proc_write = ddebug_proc_write
932 * Allocate a new ddebug_table for the given module
933 * and add it to the global list.
935 int ddebug_add_module(struct _ddebug *tab, unsigned int n,
938 struct ddebug_table *dt;
940 dt = kzalloc(sizeof(*dt), GFP_KERNEL);
942 pr_err("error adding module: %s\n", name);
946 * For built-in modules, name lives in .rodata and is
947 * immortal. For loaded modules, name points at the name[]
948 * member of struct module, which lives at least as long as
949 * this struct ddebug_table.
955 mutex_lock(&ddebug_lock);
956 list_add(&dt->link, &ddebug_tables);
957 mutex_unlock(&ddebug_lock);
959 v2pr_info("%3u debug prints in module %s\n", n, dt->mod_name);
963 /* helper for ddebug_dyndbg_(boot|module)_param_cb */
964 static int ddebug_dyndbg_param_cb(char *param, char *val,
965 const char *modname, int on_err)
969 sep = strchr(param, '.');
971 /* needed only for ddebug_dyndbg_boot_param_cb */
976 if (strcmp(param, "dyndbg"))
977 return on_err; /* determined by caller */
979 ddebug_exec_queries((val ? val : "+p"), modname);
981 return 0; /* query failure shouldn't stop module load */
984 /* handle both dyndbg and $module.dyndbg params at boot */
985 static int ddebug_dyndbg_boot_param_cb(char *param, char *val,
986 const char *unused, void *arg)
988 vpr_info("%s=\"%s\"\n", param, val);
989 return ddebug_dyndbg_param_cb(param, val, NULL, 0);
993 * modprobe foo finds foo.params in boot-args, strips "foo.", and
994 * passes them to load_module(). This callback gets unknown params,
995 * processes dyndbg params, rejects others.
997 int ddebug_dyndbg_module_param_cb(char *param, char *val, const char *module)
999 vpr_info("module: %s %s=\"%s\"\n", module, param, val);
1000 return ddebug_dyndbg_param_cb(param, val, module, -ENOENT);
1003 static void ddebug_table_free(struct ddebug_table *dt)
1005 list_del_init(&dt->link);
1010 * Called in response to a module being unloaded. Removes
1011 * any ddebug_table's which point at the module.
1013 int ddebug_remove_module(const char *mod_name)
1015 struct ddebug_table *dt, *nextdt;
1018 v2pr_info("removing module \"%s\"\n", mod_name);
1020 mutex_lock(&ddebug_lock);
1021 list_for_each_entry_safe(dt, nextdt, &ddebug_tables, link) {
1022 if (dt->mod_name == mod_name) {
1023 ddebug_table_free(dt);
1028 mutex_unlock(&ddebug_lock);
1032 static void ddebug_remove_all_tables(void)
1034 mutex_lock(&ddebug_lock);
1035 while (!list_empty(&ddebug_tables)) {
1036 struct ddebug_table *dt = list_entry(ddebug_tables.next,
1037 struct ddebug_table,
1039 ddebug_table_free(dt);
1041 mutex_unlock(&ddebug_lock);
1044 static __initdata int ddebug_init_success;
1046 static int __init dynamic_debug_init_control(void)
1048 struct proc_dir_entry *procfs_dir;
1049 struct dentry *debugfs_dir;
1051 if (!ddebug_init_success)
1054 /* Create the control file in debugfs if it is enabled */
1055 if (debugfs_initialized()) {
1056 debugfs_dir = debugfs_create_dir("dynamic_debug", NULL);
1057 debugfs_create_file("control", 0644, debugfs_dir, NULL,
1061 /* Also create the control file in procfs */
1062 procfs_dir = proc_mkdir("dynamic_debug", NULL);
1064 proc_create("control", 0644, procfs_dir, &proc_fops);
1069 static int __init dynamic_debug_init(void)
1071 struct _ddebug *iter, *iter_start;
1072 const char *modname = NULL;
1075 int n = 0, entries = 0, modct = 0;
1077 if (&__start___dyndbg == &__stop___dyndbg) {
1078 if (IS_ENABLED(CONFIG_DYNAMIC_DEBUG)) {
1079 pr_warn("_ddebug table is empty in a CONFIG_DYNAMIC_DEBUG build\n");
1082 pr_info("Ignore empty _ddebug table in a CONFIG_DYNAMIC_DEBUG_CORE build\n");
1083 ddebug_init_success = 1;
1086 iter = __start___dyndbg;
1087 modname = iter->modname;
1089 for (; iter < __stop___dyndbg; iter++) {
1091 if (strcmp(modname, iter->modname)) {
1093 ret = ddebug_add_module(iter_start, n, modname);
1097 modname = iter->modname;
1102 ret = ddebug_add_module(iter_start, n, modname);
1106 ddebug_init_success = 1;
1107 vpr_info("%d prdebugs in %d modules, %d KiB in ddebug tables, %d kiB in __dyndbg section\n",
1108 entries, modct, (int)((modct * sizeof(struct ddebug_table)) >> 10),
1109 (int)((entries * sizeof(struct _ddebug)) >> 10));
1111 /* apply ddebug_query boot param, dont unload tables on err */
1112 if (ddebug_setup_string[0] != '\0') {
1113 pr_warn("ddebug_query param name is deprecated, change it to dyndbg\n");
1114 ret = ddebug_exec_queries(ddebug_setup_string, NULL);
1116 pr_warn("Invalid ddebug boot param %s\n",
1117 ddebug_setup_string);
1119 pr_info("%d changes by ddebug_query\n", ret);
1121 /* now that ddebug tables are loaded, process all boot args
1122 * again to find and activate queries given in dyndbg params.
1123 * While this has already been done for known boot params, it
1124 * ignored the unknown ones (dyndbg in particular). Reusing
1125 * parse_args avoids ad-hoc parsing. This will also attempt
1126 * to activate queries for not-yet-loaded modules, which is
1127 * slightly noisy if verbose, but harmless.
1129 cmdline = kstrdup(saved_command_line, GFP_KERNEL);
1130 parse_args("dyndbg params", cmdline, NULL,
1131 0, 0, 0, NULL, &ddebug_dyndbg_boot_param_cb);
1136 ddebug_remove_all_tables();
1139 /* Allow early initialization for boot messages via boot param */
1140 early_initcall(dynamic_debug_init);
1142 /* Debugfs setup must be done later */
1143 fs_initcall(dynamic_debug_init_control);