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) KBUILD_MODNAME ":%s: " fmt, __func__
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___verbose[];
43 extern struct _ddebug __stop___verbose[];
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 static DEFINE_MUTEX(ddebug_lock);
66 static LIST_HEAD(ddebug_tables);
68 module_param(verbose, int, 0644);
70 /* Return the path relative to source root */
71 static inline const char *trim_prefix(const char *path)
73 int skip = strlen(__FILE__) - strlen("lib/dynamic_debug.c");
75 if (strncmp(path, __FILE__, skip))
76 skip = 0; /* prefix mismatch, don't skip */
81 static struct { unsigned flag:8; char opt_char; } opt_array[] = {
82 { _DPRINTK_FLAGS_PRINT, 'p' },
83 { _DPRINTK_FLAGS_INCL_MODNAME, 'm' },
84 { _DPRINTK_FLAGS_INCL_FUNCNAME, 'f' },
85 { _DPRINTK_FLAGS_INCL_LINENO, 'l' },
86 { _DPRINTK_FLAGS_INCL_TID, 't' },
87 { _DPRINTK_FLAGS_NONE, '_' },
90 struct flagsbuf { char buf[ARRAY_SIZE(opt_array)+1]; };
92 /* format a string into buf[] which describes the _ddebug's flags */
93 static char *ddebug_describe_flags(unsigned int flags, struct flagsbuf *fb)
98 for (i = 0; i < ARRAY_SIZE(opt_array); ++i)
99 if (flags & opt_array[i].flag)
100 *p++ = opt_array[i].opt_char;
108 #define vpr_info(fmt, ...) \
111 pr_info(fmt, ##__VA_ARGS__); \
114 static void vpr_info_dq(const struct ddebug_query *query, const char *msg)
116 /* trim any trailing newlines */
120 fmtlen = strlen(query->format);
121 while (fmtlen && query->format[fmtlen - 1] == '\n')
125 vpr_info("%s: func=\"%s\" file=\"%s\" module=\"%s\" format=\"%.*s\" lineno=%u-%u\n",
127 query->function ? query->function : "",
128 query->filename ? query->filename : "",
129 query->module ? query->module : "",
130 fmtlen, query->format ? query->format : "",
131 query->first_lineno, query->last_lineno);
135 * Search the tables for _ddebug's which match the given `query' and
136 * apply the `flags' and `mask' to them. Returns number of matching
137 * callsites, normally the same as number of changes. If verbose,
138 * logs the changes. Takes ddebug_lock.
140 static int ddebug_change(const struct ddebug_query *query,
141 unsigned int flags, unsigned int mask)
144 struct ddebug_table *dt;
145 unsigned int newflags;
146 unsigned int nfound = 0;
147 struct flagsbuf fbuf;
149 /* search for matching ddebugs */
150 mutex_lock(&ddebug_lock);
151 list_for_each_entry(dt, &ddebug_tables, link) {
153 /* match against the module name */
155 !match_wildcard(query->module, dt->mod_name))
158 for (i = 0; i < dt->num_ddebugs; i++) {
159 struct _ddebug *dp = &dt->ddebugs[i];
161 /* match against the source filename */
162 if (query->filename &&
163 !match_wildcard(query->filename, dp->filename) &&
164 !match_wildcard(query->filename,
165 kbasename(dp->filename)) &&
166 !match_wildcard(query->filename,
167 trim_prefix(dp->filename)))
170 /* match against the function */
171 if (query->function &&
172 !match_wildcard(query->function, dp->function))
175 /* match against the format */
177 !strstr(dp->format, query->format))
180 /* match against the line number range */
181 if (query->first_lineno &&
182 dp->lineno < query->first_lineno)
184 if (query->last_lineno &&
185 dp->lineno > query->last_lineno)
190 newflags = (dp->flags & mask) | flags;
191 if (newflags == dp->flags)
193 #ifdef CONFIG_JUMP_LABEL
194 if (dp->flags & _DPRINTK_FLAGS_PRINT) {
195 if (!(flags & _DPRINTK_FLAGS_PRINT))
196 static_branch_disable(&dp->key.dd_key_true);
197 } else if (flags & _DPRINTK_FLAGS_PRINT)
198 static_branch_enable(&dp->key.dd_key_true);
200 dp->flags = newflags;
201 vpr_info("changed %s:%d [%s]%s =%s\n",
202 trim_prefix(dp->filename), dp->lineno,
203 dt->mod_name, dp->function,
204 ddebug_describe_flags(dp->flags, &fbuf));
207 mutex_unlock(&ddebug_lock);
209 if (!nfound && verbose)
210 pr_info("no matches for query\n");
216 * Split the buffer `buf' into space-separated words.
217 * Handles simple " and ' quoting, i.e. without nested,
218 * embedded or escaped \". Return the number of words
221 static int ddebug_tokenize(char *buf, char *words[], int maxwords)
228 /* Skip leading whitespace */
229 buf = skip_spaces(buf);
231 break; /* oh, it was trailing whitespace */
233 break; /* token starts comment, skip rest of line */
235 /* find `end' of word, whitespace separated or quoted */
236 if (*buf == '"' || *buf == '\'') {
238 for (end = buf; *end && *end != quote; end++)
241 pr_err("unclosed quote: %s\n", buf);
242 return -EINVAL; /* unclosed quote */
245 for (end = buf; *end && !isspace(*end); end++)
250 /* `buf' is start of word, `end' is one past its end */
251 if (nwords == maxwords) {
252 pr_err("too many words, legal max <=%d\n", maxwords);
253 return -EINVAL; /* ran out of words[] before bytes */
256 *end++ = '\0'; /* terminate the word */
257 words[nwords++] = buf;
263 pr_info("split into words:");
264 for (i = 0; i < nwords; i++)
265 pr_cont(" \"%s\"", words[i]);
273 * Parse a single line number. Note that the empty string ""
274 * is treated as a special case and converted to zero, which
275 * is later treated as a "don't care" value.
277 static inline int parse_lineno(const char *str, unsigned int *val)
284 if (kstrtouint(str, 10, val) < 0) {
285 pr_err("bad line-number: %s\n", str);
291 static int check_set(const char **dest, char *src, char *name)
297 pr_err("match-spec:%s val:%s overridden by %s\n",
305 * Parse words[] as a ddebug query specification, which is a series
306 * of (keyword, value) pairs chosen from these possibilities:
308 * func <function-name>
309 * file <full-pathname>
310 * file <base-filename>
311 * module <module-name>
312 * format <escaped-string-to-find-in-format>
314 * line <first-lineno>-<last-lineno> // where either may be empty
316 * Only 1 of each type is allowed.
317 * Returns 0 on success, <0 on error.
319 static int ddebug_parse_query(char *words[], int nwords,
320 struct ddebug_query *query, const char *modname)
325 /* check we have an even number of words */
326 if (nwords % 2 != 0) {
327 pr_err("expecting pairs of match-spec <value>\n");
330 memset(query, 0, sizeof(*query));
332 for (i = 0; i < nwords; i += 2) {
333 if (!strcmp(words[i], "func")) {
334 rc = check_set(&query->function, words[i+1], "func");
335 } else if (!strcmp(words[i], "file")) {
336 rc = check_set(&query->filename, words[i+1], "file");
337 } else if (!strcmp(words[i], "module")) {
338 rc = check_set(&query->module, words[i+1], "module");
339 } else if (!strcmp(words[i], "format")) {
340 string_unescape_inplace(words[i+1], UNESCAPE_SPACE |
343 rc = check_set(&query->format, words[i+1], "format");
344 } else if (!strcmp(words[i], "line")) {
345 char *first = words[i+1];
346 char *last = strchr(first, '-');
347 if (query->first_lineno || query->last_lineno) {
348 pr_err("match-spec: line used 2x\n");
353 if (parse_lineno(first, &query->first_lineno) < 0)
356 /* range <first>-<last> */
357 if (parse_lineno(last, &query->last_lineno) < 0)
360 /* special case for last lineno not specified */
361 if (query->last_lineno == 0)
362 query->last_lineno = UINT_MAX;
364 if (query->last_lineno < query->first_lineno) {
365 pr_err("last-line:%d < 1st-line:%d\n",
367 query->first_lineno);
371 query->last_lineno = query->first_lineno;
374 pr_err("unknown keyword \"%s\"\n", words[i]);
380 if (!query->module && modname)
382 * support $modname.dyndbg=<multiple queries>, when
383 * not given in the query itself
385 query->module = modname;
387 vpr_info_dq(query, "parsed");
392 * Parse `str' as a flags specification, format [-+=][p]+.
393 * Sets up *maskp and *flagsp to be used when changing the
394 * flags fields of matched _ddebug's. Returns 0 on success
397 static int ddebug_parse_flags(const char *str, unsigned int *flagsp,
410 pr_err("bad flag-op %c, at start of %s\n", *str, str);
413 vpr_info("op='%c'\n", op);
415 for (; *str ; ++str) {
416 for (i = ARRAY_SIZE(opt_array) - 1; i >= 0; i--) {
417 if (*str == opt_array[i].opt_char) {
418 flags |= opt_array[i].flag;
423 pr_err("unknown flag '%c' in \"%s\"\n", *str, str);
427 vpr_info("flags=0x%x\n", flags);
429 /* calculate final *flagsp, *maskp according to mask and op */
444 vpr_info("*flagsp=0x%x *maskp=0x%x\n", *flagsp, *maskp);
448 static int ddebug_exec_query(char *query_string, const char *modname)
450 unsigned int flags = 0, mask = 0;
451 struct ddebug_query query;
454 char *words[MAXWORDS];
456 nwords = ddebug_tokenize(query_string, words, MAXWORDS);
458 pr_err("tokenize failed\n");
461 /* check flags 1st (last arg) so query is pairs of spec,val */
462 if (ddebug_parse_flags(words[nwords-1], &flags, &mask)) {
463 pr_err("flags parse failed\n");
466 if (ddebug_parse_query(words, nwords-1, &query, modname)) {
467 pr_err("query parse failed\n");
470 /* actually go and implement the change */
471 nfound = ddebug_change(&query, flags, mask);
472 vpr_info_dq(&query, nfound ? "applied" : "no-match");
477 /* handle multiple queries in query string, continue on error, return
478 last error or number of matching callsites. Module name is either
479 in param (for boot arg) or perhaps in query string.
481 static int ddebug_exec_queries(char *query, const char *modname)
484 int i, errs = 0, exitcode = 0, rc, nfound = 0;
486 for (i = 0; query; query = split) {
487 split = strpbrk(query, ";\n");
491 query = skip_spaces(query);
492 if (!query || !*query || *query == '#')
495 vpr_info("query %d: \"%s\"\n", i, query);
497 rc = ddebug_exec_query(query, modname);
506 vpr_info("processed %d queries, with %d matches, %d errs\n",
514 #define PREFIX_SIZE 64
516 static int remaining(int wrote)
518 if (PREFIX_SIZE - wrote > 0)
519 return PREFIX_SIZE - wrote;
523 static char *dynamic_emit_prefix(const struct _ddebug *desc, char *buf)
530 if (desc->flags & _DPRINTK_FLAGS_INCL_TID) {
532 pos += snprintf(buf + pos, remaining(pos), "<intr> ");
534 pos += snprintf(buf + pos, remaining(pos), "[%d] ",
535 task_pid_vnr(current));
538 if (desc->flags & _DPRINTK_FLAGS_INCL_MODNAME)
539 pos += snprintf(buf + pos, remaining(pos), "%s:",
541 if (desc->flags & _DPRINTK_FLAGS_INCL_FUNCNAME)
542 pos += snprintf(buf + pos, remaining(pos), "%s:",
544 if (desc->flags & _DPRINTK_FLAGS_INCL_LINENO)
545 pos += snprintf(buf + pos, remaining(pos), "%d:",
547 if (pos - pos_after_tid)
548 pos += snprintf(buf + pos, remaining(pos), " ");
549 if (pos >= PREFIX_SIZE)
550 buf[PREFIX_SIZE - 1] = '\0';
555 void __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...)
558 struct va_format vaf;
559 char buf[PREFIX_SIZE];
569 printk(KERN_DEBUG "%s%pV", dynamic_emit_prefix(descriptor, buf), &vaf);
573 EXPORT_SYMBOL(__dynamic_pr_debug);
575 void __dynamic_dev_dbg(struct _ddebug *descriptor,
576 const struct device *dev, const char *fmt, ...)
578 struct va_format vaf;
590 printk(KERN_DEBUG "(NULL device *): %pV", &vaf);
592 char buf[PREFIX_SIZE];
594 dev_printk_emit(LOGLEVEL_DEBUG, dev, "%s%s %s: %pV",
595 dynamic_emit_prefix(descriptor, buf),
596 dev_driver_string(dev), dev_name(dev),
602 EXPORT_SYMBOL(__dynamic_dev_dbg);
606 void __dynamic_netdev_dbg(struct _ddebug *descriptor,
607 const struct net_device *dev, const char *fmt, ...)
609 struct va_format vaf;
620 if (dev && dev->dev.parent) {
621 char buf[PREFIX_SIZE];
623 dev_printk_emit(LOGLEVEL_DEBUG, dev->dev.parent,
625 dynamic_emit_prefix(descriptor, buf),
626 dev_driver_string(dev->dev.parent),
627 dev_name(dev->dev.parent),
628 netdev_name(dev), netdev_reg_state(dev),
631 printk(KERN_DEBUG "%s%s: %pV", netdev_name(dev),
632 netdev_reg_state(dev), &vaf);
634 printk(KERN_DEBUG "(NULL net_device): %pV", &vaf);
639 EXPORT_SYMBOL(__dynamic_netdev_dbg);
643 #if IS_ENABLED(CONFIG_INFINIBAND)
645 void __dynamic_ibdev_dbg(struct _ddebug *descriptor,
646 const struct ib_device *ibdev, const char *fmt, ...)
648 struct va_format vaf;
656 if (ibdev && ibdev->dev.parent) {
657 char buf[PREFIX_SIZE];
659 dev_printk_emit(LOGLEVEL_DEBUG, ibdev->dev.parent,
661 dynamic_emit_prefix(descriptor, buf),
662 dev_driver_string(ibdev->dev.parent),
663 dev_name(ibdev->dev.parent),
664 dev_name(&ibdev->dev),
667 printk(KERN_DEBUG "%s: %pV", dev_name(&ibdev->dev), &vaf);
669 printk(KERN_DEBUG "(NULL ib_device): %pV", &vaf);
674 EXPORT_SYMBOL(__dynamic_ibdev_dbg);
678 #define DDEBUG_STRING_SIZE 1024
679 static __initdata char ddebug_setup_string[DDEBUG_STRING_SIZE];
681 static __init int ddebug_setup_query(char *str)
683 if (strlen(str) >= DDEBUG_STRING_SIZE) {
684 pr_warn("ddebug boot param string too large\n");
687 strlcpy(ddebug_setup_string, str, DDEBUG_STRING_SIZE);
691 __setup("ddebug_query=", ddebug_setup_query);
694 * File_ops->write method for <debugfs>/dynamic_debug/control. Gathers the
695 * command text from userspace, parses and executes it.
697 #define USER_BUF_PAGE 4096
698 static ssize_t ddebug_proc_write(struct file *file, const char __user *ubuf,
699 size_t len, loff_t *offp)
706 if (len > USER_BUF_PAGE - 1) {
707 pr_warn("expected <%d bytes into control\n", USER_BUF_PAGE);
710 tmpbuf = memdup_user_nul(ubuf, len);
712 return PTR_ERR(tmpbuf);
713 vpr_info("read %d bytes from userspace\n", (int)len);
715 ret = ddebug_exec_queries(tmpbuf, NULL);
725 * Set the iterator to point to the first _ddebug object
726 * and return a pointer to that first object. Returns
727 * NULL if there are no _ddebugs at all.
729 static struct _ddebug *ddebug_iter_first(struct ddebug_iter *iter)
731 if (list_empty(&ddebug_tables)) {
736 iter->table = list_entry(ddebug_tables.next,
737 struct ddebug_table, link);
739 return &iter->table->ddebugs[iter->idx];
743 * Advance the iterator to point to the next _ddebug
744 * object from the one the iterator currently points at,
745 * and returns a pointer to the new _ddebug. Returns
746 * NULL if the iterator has seen all the _ddebugs.
748 static struct _ddebug *ddebug_iter_next(struct ddebug_iter *iter)
750 if (iter->table == NULL)
752 if (++iter->idx == iter->table->num_ddebugs) {
753 /* iterate to next table */
755 if (list_is_last(&iter->table->link, &ddebug_tables)) {
759 iter->table = list_entry(iter->table->link.next,
760 struct ddebug_table, link);
762 return &iter->table->ddebugs[iter->idx];
766 * Seq_ops start method. Called at the start of every
767 * read() call from userspace. Takes the ddebug_lock and
768 * seeks the seq_file's iterator to the given position.
770 static void *ddebug_proc_start(struct seq_file *m, loff_t *pos)
772 struct ddebug_iter *iter = m->private;
776 vpr_info("called m=%p *pos=%lld\n", m, (unsigned long long)*pos);
778 mutex_lock(&ddebug_lock);
781 return SEQ_START_TOKEN;
784 dp = ddebug_iter_first(iter);
785 while (dp != NULL && --n > 0)
786 dp = ddebug_iter_next(iter);
791 * Seq_ops next method. Called several times within a read()
792 * call from userspace, with ddebug_lock held. Walks to the
793 * next _ddebug object with a special case for the header line.
795 static void *ddebug_proc_next(struct seq_file *m, void *p, loff_t *pos)
797 struct ddebug_iter *iter = m->private;
800 vpr_info("called m=%p p=%p *pos=%lld\n",
801 m, p, (unsigned long long)*pos);
803 if (p == SEQ_START_TOKEN)
804 dp = ddebug_iter_first(iter);
806 dp = ddebug_iter_next(iter);
812 * Seq_ops show method. Called several times within a read()
813 * call from userspace, with ddebug_lock held. Formats the
814 * current _ddebug as a single human-readable line, with a
815 * special case for the header line.
817 static int ddebug_proc_show(struct seq_file *m, void *p)
819 struct ddebug_iter *iter = m->private;
820 struct _ddebug *dp = p;
821 struct flagsbuf flags;
823 vpr_info("called m=%p p=%p\n", m, p);
825 if (p == SEQ_START_TOKEN) {
827 "# filename:lineno [module]function flags format\n");
831 seq_printf(m, "%s:%u [%s]%s =%s \"",
832 trim_prefix(dp->filename), dp->lineno,
833 iter->table->mod_name, dp->function,
834 ddebug_describe_flags(dp->flags, &flags));
835 seq_escape(m, dp->format, "\t\r\n\"");
842 * Seq_ops stop method. Called at the end of each read()
843 * call from userspace. Drops ddebug_lock.
845 static void ddebug_proc_stop(struct seq_file *m, void *p)
847 vpr_info("called m=%p p=%p\n", m, p);
848 mutex_unlock(&ddebug_lock);
851 static const struct seq_operations ddebug_proc_seqops = {
852 .start = ddebug_proc_start,
853 .next = ddebug_proc_next,
854 .show = ddebug_proc_show,
855 .stop = ddebug_proc_stop
859 * File_ops->open method for <debugfs>/dynamic_debug/control. Does
860 * the seq_file setup dance, and also creates an iterator to walk the
861 * _ddebugs. Note that we create a seq_file always, even for O_WRONLY
862 * files where it's not needed, as doing so simplifies the ->release
865 static int ddebug_proc_open(struct inode *inode, struct file *file)
867 vpr_info("called\n");
868 return seq_open_private(file, &ddebug_proc_seqops,
869 sizeof(struct ddebug_iter));
872 static const struct file_operations ddebug_proc_fops = {
873 .owner = THIS_MODULE,
874 .open = ddebug_proc_open,
877 .release = seq_release_private,
878 .write = ddebug_proc_write
882 * Allocate a new ddebug_table for the given module
883 * and add it to the global list.
885 int ddebug_add_module(struct _ddebug *tab, unsigned int n,
888 struct ddebug_table *dt;
890 dt = kzalloc(sizeof(*dt), GFP_KERNEL);
892 pr_err("error adding module: %s\n", name);
896 * For built-in modules, name lives in .rodata and is
897 * immortal. For loaded modules, name points at the name[]
898 * member of struct module, which lives at least as long as
899 * this struct ddebug_table.
905 mutex_lock(&ddebug_lock);
906 list_add_tail(&dt->link, &ddebug_tables);
907 mutex_unlock(&ddebug_lock);
909 vpr_info("%u debug prints in module %s\n", n, dt->mod_name);
913 /* helper for ddebug_dyndbg_(boot|module)_param_cb */
914 static int ddebug_dyndbg_param_cb(char *param, char *val,
915 const char *modname, int on_err)
919 sep = strchr(param, '.');
921 /* needed only for ddebug_dyndbg_boot_param_cb */
926 if (strcmp(param, "dyndbg"))
927 return on_err; /* determined by caller */
929 ddebug_exec_queries((val ? val : "+p"), modname);
931 return 0; /* query failure shouldnt stop module load */
934 /* handle both dyndbg and $module.dyndbg params at boot */
935 static int ddebug_dyndbg_boot_param_cb(char *param, char *val,
936 const char *unused, void *arg)
938 vpr_info("%s=\"%s\"\n", param, val);
939 return ddebug_dyndbg_param_cb(param, val, NULL, 0);
943 * modprobe foo finds foo.params in boot-args, strips "foo.", and
944 * passes them to load_module(). This callback gets unknown params,
945 * processes dyndbg params, rejects others.
947 int ddebug_dyndbg_module_param_cb(char *param, char *val, const char *module)
949 vpr_info("module: %s %s=\"%s\"\n", module, param, val);
950 return ddebug_dyndbg_param_cb(param, val, module, -ENOENT);
953 static void ddebug_table_free(struct ddebug_table *dt)
955 list_del_init(&dt->link);
960 * Called in response to a module being unloaded. Removes
961 * any ddebug_table's which point at the module.
963 int ddebug_remove_module(const char *mod_name)
965 struct ddebug_table *dt, *nextdt;
968 vpr_info("removing module \"%s\"\n", mod_name);
970 mutex_lock(&ddebug_lock);
971 list_for_each_entry_safe(dt, nextdt, &ddebug_tables, link) {
972 if (dt->mod_name == mod_name) {
973 ddebug_table_free(dt);
978 mutex_unlock(&ddebug_lock);
982 static void ddebug_remove_all_tables(void)
984 mutex_lock(&ddebug_lock);
985 while (!list_empty(&ddebug_tables)) {
986 struct ddebug_table *dt = list_entry(ddebug_tables.next,
989 ddebug_table_free(dt);
991 mutex_unlock(&ddebug_lock);
994 static __initdata int ddebug_init_success;
996 static int __init dynamic_debug_init_debugfs(void)
1000 if (!ddebug_init_success)
1003 dir = debugfs_create_dir("dynamic_debug", NULL);
1004 debugfs_create_file("control", 0644, dir, NULL, &ddebug_proc_fops);
1009 static int __init dynamic_debug_init(void)
1011 struct _ddebug *iter, *iter_start;
1012 const char *modname = NULL;
1015 int n = 0, entries = 0, modct = 0;
1016 int verbose_bytes = 0;
1018 if (&__start___verbose == &__stop___verbose) {
1019 pr_warn("_ddebug table is empty in a CONFIG_DYNAMIC_DEBUG build\n");
1022 iter = __start___verbose;
1023 modname = iter->modname;
1025 for (; iter < __stop___verbose; iter++) {
1027 verbose_bytes += strlen(iter->modname) + strlen(iter->function)
1028 + strlen(iter->filename) + strlen(iter->format);
1030 if (strcmp(modname, iter->modname)) {
1032 ret = ddebug_add_module(iter_start, n, modname);
1036 modname = iter->modname;
1041 ret = ddebug_add_module(iter_start, n, modname);
1045 ddebug_init_success = 1;
1046 vpr_info("%d modules, %d entries and %d bytes in ddebug tables, %d bytes in (readonly) verbose section\n",
1047 modct, entries, (int)(modct * sizeof(struct ddebug_table)),
1048 verbose_bytes + (int)(__stop___verbose - __start___verbose));
1050 /* apply ddebug_query boot param, dont unload tables on err */
1051 if (ddebug_setup_string[0] != '\0') {
1052 pr_warn("ddebug_query param name is deprecated, change it to dyndbg\n");
1053 ret = ddebug_exec_queries(ddebug_setup_string, NULL);
1055 pr_warn("Invalid ddebug boot param %s\n",
1056 ddebug_setup_string);
1058 pr_info("%d changes by ddebug_query\n", ret);
1060 /* now that ddebug tables are loaded, process all boot args
1061 * again to find and activate queries given in dyndbg params.
1062 * While this has already been done for known boot params, it
1063 * ignored the unknown ones (dyndbg in particular). Reusing
1064 * parse_args avoids ad-hoc parsing. This will also attempt
1065 * to activate queries for not-yet-loaded modules, which is
1066 * slightly noisy if verbose, but harmless.
1068 cmdline = kstrdup(saved_command_line, GFP_KERNEL);
1069 parse_args("dyndbg params", cmdline, NULL,
1070 0, 0, 0, NULL, &ddebug_dyndbg_boot_param_cb);
1075 ddebug_remove_all_tables();
1078 /* Allow early initialization for boot messages via boot param */
1079 early_initcall(dynamic_debug_init);
1081 /* Debugfs setup must be done later */
1082 fs_initcall(dynamic_debug_init_debugfs);