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![Greg Kroah-Hartman](/assets/img/avatar_default.png)
This fixes a build breakage caused by
8ba6ebf583
"Dynamic debug: Add more flags"
Cc: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
824 lines
19 KiB
C
824 lines
19 KiB
C
/*
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* lib/dynamic_debug.c
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*
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* make pr_debug()/dev_dbg() calls runtime configurable based upon their
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* source module.
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*
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* Copyright (C) 2008 Jason Baron <jbaron@redhat.com>
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* By Greg Banks <gnb@melbourne.sgi.com>
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* Copyright (c) 2008 Silicon Graphics Inc. All Rights Reserved.
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* Copyright (C) 2011 Bart Van Assche. All Rights Reserved.
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*/
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/moduleparam.h>
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#include <linux/kallsyms.h>
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#include <linux/version.h>
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#include <linux/types.h>
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#include <linux/mutex.h>
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#include <linux/proc_fs.h>
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#include <linux/seq_file.h>
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#include <linux/list.h>
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#include <linux/sysctl.h>
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#include <linux/ctype.h>
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#include <linux/string.h>
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#include <linux/uaccess.h>
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#include <linux/dynamic_debug.h>
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#include <linux/debugfs.h>
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#include <linux/slab.h>
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#include <linux/jump_label.h>
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#include <linux/hardirq.h>
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#include <linux/sched.h>
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extern struct _ddebug __start___verbose[];
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extern struct _ddebug __stop___verbose[];
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struct ddebug_table {
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struct list_head link;
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char *mod_name;
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unsigned int num_ddebugs;
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unsigned int num_enabled;
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struct _ddebug *ddebugs;
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};
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struct ddebug_query {
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const char *filename;
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const char *module;
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const char *function;
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const char *format;
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unsigned int first_lineno, last_lineno;
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};
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struct ddebug_iter {
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struct ddebug_table *table;
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unsigned int idx;
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};
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static DEFINE_MUTEX(ddebug_lock);
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static LIST_HEAD(ddebug_tables);
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static int verbose = 0;
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/* Return the last part of a pathname */
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static inline const char *basename(const char *path)
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{
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const char *tail = strrchr(path, '/');
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return tail ? tail+1 : path;
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}
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static struct { unsigned flag:8; char opt_char; } opt_array[] = {
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{ _DPRINTK_FLAGS_PRINT, 'p' },
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{ _DPRINTK_FLAGS_INCL_MODNAME, 'm' },
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{ _DPRINTK_FLAGS_INCL_FUNCNAME, 'f' },
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{ _DPRINTK_FLAGS_INCL_LINENO, 'l' },
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{ _DPRINTK_FLAGS_INCL_TID, 't' },
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};
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/* format a string into buf[] which describes the _ddebug's flags */
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static char *ddebug_describe_flags(struct _ddebug *dp, char *buf,
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size_t maxlen)
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{
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char *p = buf;
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int i;
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BUG_ON(maxlen < 4);
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for (i = 0; i < ARRAY_SIZE(opt_array); ++i)
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if (dp->flags & opt_array[i].flag)
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*p++ = opt_array[i].opt_char;
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if (p == buf)
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*p++ = '-';
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*p = '\0';
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return buf;
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}
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/*
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* Search the tables for _ddebug's which match the given
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* `query' and apply the `flags' and `mask' to them. Tells
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* the user which ddebug's were changed, or whether none
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* were matched.
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*/
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static void ddebug_change(const struct ddebug_query *query,
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unsigned int flags, unsigned int mask)
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{
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int i;
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struct ddebug_table *dt;
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unsigned int newflags;
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unsigned int nfound = 0;
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char flagbuf[8];
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/* search for matching ddebugs */
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mutex_lock(&ddebug_lock);
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list_for_each_entry(dt, &ddebug_tables, link) {
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/* match against the module name */
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if (query->module != NULL &&
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strcmp(query->module, dt->mod_name))
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continue;
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for (i = 0 ; i < dt->num_ddebugs ; i++) {
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struct _ddebug *dp = &dt->ddebugs[i];
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/* match against the source filename */
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if (query->filename != NULL &&
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strcmp(query->filename, dp->filename) &&
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strcmp(query->filename, basename(dp->filename)))
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continue;
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/* match against the function */
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if (query->function != NULL &&
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strcmp(query->function, dp->function))
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continue;
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/* match against the format */
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if (query->format != NULL &&
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strstr(dp->format, query->format) == NULL)
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continue;
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/* match against the line number range */
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if (query->first_lineno &&
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dp->lineno < query->first_lineno)
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continue;
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if (query->last_lineno &&
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dp->lineno > query->last_lineno)
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continue;
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nfound++;
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newflags = (dp->flags & mask) | flags;
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if (newflags == dp->flags)
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continue;
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if (!newflags)
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dt->num_enabled--;
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else if (!dp->flags)
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dt->num_enabled++;
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dp->flags = newflags;
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if (newflags)
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dp->enabled = 1;
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else
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dp->enabled = 0;
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if (verbose)
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printk(KERN_INFO
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"ddebug: changed %s:%d [%s]%s %s\n",
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dp->filename, dp->lineno,
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dt->mod_name, dp->function,
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ddebug_describe_flags(dp, flagbuf,
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sizeof(flagbuf)));
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}
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}
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mutex_unlock(&ddebug_lock);
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if (!nfound && verbose)
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printk(KERN_INFO "ddebug: no matches for query\n");
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}
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/*
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* Split the buffer `buf' into space-separated words.
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* Handles simple " and ' quoting, i.e. without nested,
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* embedded or escaped \". Return the number of words
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* or <0 on error.
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*/
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static int ddebug_tokenize(char *buf, char *words[], int maxwords)
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{
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int nwords = 0;
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while (*buf) {
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char *end;
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/* Skip leading whitespace */
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buf = skip_spaces(buf);
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if (!*buf)
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break; /* oh, it was trailing whitespace */
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/* Run `end' over a word, either whitespace separated or quoted */
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if (*buf == '"' || *buf == '\'') {
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int quote = *buf++;
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for (end = buf ; *end && *end != quote ; end++)
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;
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if (!*end)
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return -EINVAL; /* unclosed quote */
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} else {
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for (end = buf ; *end && !isspace(*end) ; end++)
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;
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BUG_ON(end == buf);
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}
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/* Here `buf' is the start of the word, `end' is one past the end */
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if (nwords == maxwords)
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return -EINVAL; /* ran out of words[] before bytes */
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if (*end)
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*end++ = '\0'; /* terminate the word */
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words[nwords++] = buf;
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buf = end;
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}
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if (verbose) {
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int i;
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printk(KERN_INFO "%s: split into words:", __func__);
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for (i = 0 ; i < nwords ; i++)
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printk(" \"%s\"", words[i]);
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printk("\n");
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}
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return nwords;
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}
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/*
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* Parse a single line number. Note that the empty string ""
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* is treated as a special case and converted to zero, which
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* is later treated as a "don't care" value.
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*/
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static inline int parse_lineno(const char *str, unsigned int *val)
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{
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char *end = NULL;
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BUG_ON(str == NULL);
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if (*str == '\0') {
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*val = 0;
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return 0;
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}
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*val = simple_strtoul(str, &end, 10);
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return end == NULL || end == str || *end != '\0' ? -EINVAL : 0;
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}
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/*
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* Undo octal escaping in a string, inplace. This is useful to
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* allow the user to express a query which matches a format
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* containing embedded spaces.
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*/
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#define isodigit(c) ((c) >= '0' && (c) <= '7')
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static char *unescape(char *str)
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{
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char *in = str;
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char *out = str;
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while (*in) {
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if (*in == '\\') {
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if (in[1] == '\\') {
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*out++ = '\\';
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in += 2;
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continue;
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} else if (in[1] == 't') {
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*out++ = '\t';
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in += 2;
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continue;
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} else if (in[1] == 'n') {
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*out++ = '\n';
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in += 2;
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continue;
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} else if (isodigit(in[1]) &&
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isodigit(in[2]) &&
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isodigit(in[3])) {
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*out++ = ((in[1] - '0')<<6) |
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((in[2] - '0')<<3) |
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(in[3] - '0');
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in += 4;
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continue;
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}
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}
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*out++ = *in++;
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}
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*out = '\0';
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return str;
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}
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/*
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* Parse words[] as a ddebug query specification, which is a series
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* of (keyword, value) pairs chosen from these possibilities:
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*
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* func <function-name>
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* file <full-pathname>
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* file <base-filename>
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* module <module-name>
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* format <escaped-string-to-find-in-format>
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* line <lineno>
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* line <first-lineno>-<last-lineno> // where either may be empty
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*/
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static int ddebug_parse_query(char *words[], int nwords,
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struct ddebug_query *query)
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{
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unsigned int i;
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/* check we have an even number of words */
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if (nwords % 2 != 0)
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return -EINVAL;
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memset(query, 0, sizeof(*query));
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for (i = 0 ; i < nwords ; i += 2) {
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if (!strcmp(words[i], "func"))
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query->function = words[i+1];
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else if (!strcmp(words[i], "file"))
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query->filename = words[i+1];
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else if (!strcmp(words[i], "module"))
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query->module = words[i+1];
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else if (!strcmp(words[i], "format"))
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query->format = unescape(words[i+1]);
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else if (!strcmp(words[i], "line")) {
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char *first = words[i+1];
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char *last = strchr(first, '-');
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if (last)
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*last++ = '\0';
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if (parse_lineno(first, &query->first_lineno) < 0)
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return -EINVAL;
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if (last != NULL) {
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/* range <first>-<last> */
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if (parse_lineno(last, &query->last_lineno) < 0)
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return -EINVAL;
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} else {
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query->last_lineno = query->first_lineno;
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}
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} else {
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if (verbose)
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printk(KERN_ERR "%s: unknown keyword \"%s\"\n",
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__func__, words[i]);
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return -EINVAL;
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}
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}
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if (verbose)
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printk(KERN_INFO "%s: q->function=\"%s\" q->filename=\"%s\" "
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"q->module=\"%s\" q->format=\"%s\" q->lineno=%u-%u\n",
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__func__, query->function, query->filename,
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query->module, query->format, query->first_lineno,
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query->last_lineno);
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return 0;
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}
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/*
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* Parse `str' as a flags specification, format [-+=][p]+.
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* Sets up *maskp and *flagsp to be used when changing the
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* flags fields of matched _ddebug's. Returns 0 on success
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* or <0 on error.
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*/
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static int ddebug_parse_flags(const char *str, unsigned int *flagsp,
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unsigned int *maskp)
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{
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unsigned flags = 0;
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int op = '=', i;
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switch (*str) {
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case '+':
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case '-':
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case '=':
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op = *str++;
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break;
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default:
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return -EINVAL;
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}
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if (verbose)
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printk(KERN_INFO "%s: op='%c'\n", __func__, op);
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for ( ; *str ; ++str) {
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for (i = ARRAY_SIZE(opt_array) - 1; i >= 0; i--) {
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if (*str == opt_array[i].opt_char) {
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flags |= opt_array[i].flag;
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break;
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}
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}
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if (i < 0)
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return -EINVAL;
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}
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if (flags == 0)
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return -EINVAL;
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if (verbose)
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printk(KERN_INFO "%s: flags=0x%x\n", __func__, flags);
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/* calculate final *flagsp, *maskp according to mask and op */
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switch (op) {
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case '=':
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*maskp = 0;
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*flagsp = flags;
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break;
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case '+':
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*maskp = ~0U;
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*flagsp = flags;
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break;
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case '-':
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*maskp = ~flags;
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*flagsp = 0;
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break;
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}
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if (verbose)
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printk(KERN_INFO "%s: *flagsp=0x%x *maskp=0x%x\n",
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__func__, *flagsp, *maskp);
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return 0;
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}
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static int ddebug_exec_query(char *query_string)
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{
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unsigned int flags = 0, mask = 0;
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struct ddebug_query query;
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#define MAXWORDS 9
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int nwords;
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char *words[MAXWORDS];
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nwords = ddebug_tokenize(query_string, words, MAXWORDS);
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if (nwords <= 0)
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return -EINVAL;
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if (ddebug_parse_query(words, nwords-1, &query))
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return -EINVAL;
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if (ddebug_parse_flags(words[nwords-1], &flags, &mask))
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return -EINVAL;
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/* actually go and implement the change */
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ddebug_change(&query, flags, mask);
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return 0;
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}
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int __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...)
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{
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va_list args;
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int res;
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BUG_ON(!descriptor);
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BUG_ON(!fmt);
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va_start(args, fmt);
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res = printk(KERN_DEBUG);
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if (descriptor->flags & _DPRINTK_FLAGS_INCL_TID) {
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if (in_interrupt())
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res += printk(KERN_CONT "<intr> ");
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else
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res += printk(KERN_CONT "[%d] ", task_pid_vnr(current));
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}
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if (descriptor->flags & _DPRINTK_FLAGS_INCL_MODNAME)
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res += printk(KERN_CONT "%s:", descriptor->modname);
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if (descriptor->flags & _DPRINTK_FLAGS_INCL_FUNCNAME)
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res += printk(KERN_CONT "%s:", descriptor->function);
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if (descriptor->flags & _DPRINTK_FLAGS_INCL_LINENO)
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res += printk(KERN_CONT "%d ", descriptor->lineno);
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res += vprintk(fmt, args);
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va_end(args);
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|
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return res;
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}
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EXPORT_SYMBOL(__dynamic_pr_debug);
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|
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static __initdata char ddebug_setup_string[1024];
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static __init int ddebug_setup_query(char *str)
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{
|
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if (strlen(str) >= 1024) {
|
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pr_warning("ddebug boot param string too large\n");
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return 0;
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}
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strcpy(ddebug_setup_string, str);
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return 1;
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}
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|
|
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__setup("ddebug_query=", ddebug_setup_query);
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|
|
/*
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* File_ops->write method for <debugfs>/dynamic_debug/conrol. Gathers the
|
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* command text from userspace, parses and executes it.
|
|
*/
|
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static ssize_t ddebug_proc_write(struct file *file, const char __user *ubuf,
|
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size_t len, loff_t *offp)
|
|
{
|
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char tmpbuf[256];
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int ret;
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|
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if (len == 0)
|
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return 0;
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/* we don't check *offp -- multiple writes() are allowed */
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if (len > sizeof(tmpbuf)-1)
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return -E2BIG;
|
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if (copy_from_user(tmpbuf, ubuf, len))
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return -EFAULT;
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tmpbuf[len] = '\0';
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if (verbose)
|
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printk(KERN_INFO "%s: read %d bytes from userspace\n",
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__func__, (int)len);
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|
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ret = ddebug_exec_query(tmpbuf);
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if (ret)
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return ret;
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|
|
*offp += len;
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return len;
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}
|
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|
|
/*
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* Set the iterator to point to the first _ddebug object
|
|
* and return a pointer to that first object. Returns
|
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* NULL if there are no _ddebugs at all.
|
|
*/
|
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static struct _ddebug *ddebug_iter_first(struct ddebug_iter *iter)
|
|
{
|
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if (list_empty(&ddebug_tables)) {
|
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iter->table = NULL;
|
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iter->idx = 0;
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return NULL;
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}
|
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iter->table = list_entry(ddebug_tables.next,
|
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struct ddebug_table, link);
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iter->idx = 0;
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return &iter->table->ddebugs[iter->idx];
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}
|
|
|
|
/*
|
|
* Advance the iterator to point to the next _ddebug
|
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* object from the one the iterator currently points at,
|
|
* and returns a pointer to the new _ddebug. Returns
|
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* NULL if the iterator has seen all the _ddebugs.
|
|
*/
|
|
static struct _ddebug *ddebug_iter_next(struct ddebug_iter *iter)
|
|
{
|
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if (iter->table == NULL)
|
|
return NULL;
|
|
if (++iter->idx == iter->table->num_ddebugs) {
|
|
/* iterate to next table */
|
|
iter->idx = 0;
|
|
if (list_is_last(&iter->table->link, &ddebug_tables)) {
|
|
iter->table = NULL;
|
|
return NULL;
|
|
}
|
|
iter->table = list_entry(iter->table->link.next,
|
|
struct ddebug_table, link);
|
|
}
|
|
return &iter->table->ddebugs[iter->idx];
|
|
}
|
|
|
|
/*
|
|
* Seq_ops start method. Called at the start of every
|
|
* read() call from userspace. Takes the ddebug_lock and
|
|
* seeks the seq_file's iterator to the given position.
|
|
*/
|
|
static void *ddebug_proc_start(struct seq_file *m, loff_t *pos)
|
|
{
|
|
struct ddebug_iter *iter = m->private;
|
|
struct _ddebug *dp;
|
|
int n = *pos;
|
|
|
|
if (verbose)
|
|
printk(KERN_INFO "%s: called m=%p *pos=%lld\n",
|
|
__func__, m, (unsigned long long)*pos);
|
|
|
|
mutex_lock(&ddebug_lock);
|
|
|
|
if (!n)
|
|
return SEQ_START_TOKEN;
|
|
if (n < 0)
|
|
return NULL;
|
|
dp = ddebug_iter_first(iter);
|
|
while (dp != NULL && --n > 0)
|
|
dp = ddebug_iter_next(iter);
|
|
return dp;
|
|
}
|
|
|
|
/*
|
|
* Seq_ops next method. Called several times within a read()
|
|
* call from userspace, with ddebug_lock held. Walks to the
|
|
* next _ddebug object with a special case for the header line.
|
|
*/
|
|
static void *ddebug_proc_next(struct seq_file *m, void *p, loff_t *pos)
|
|
{
|
|
struct ddebug_iter *iter = m->private;
|
|
struct _ddebug *dp;
|
|
|
|
if (verbose)
|
|
printk(KERN_INFO "%s: called m=%p p=%p *pos=%lld\n",
|
|
__func__, m, p, (unsigned long long)*pos);
|
|
|
|
if (p == SEQ_START_TOKEN)
|
|
dp = ddebug_iter_first(iter);
|
|
else
|
|
dp = ddebug_iter_next(iter);
|
|
++*pos;
|
|
return dp;
|
|
}
|
|
|
|
/*
|
|
* Seq_ops show method. Called several times within a read()
|
|
* call from userspace, with ddebug_lock held. Formats the
|
|
* current _ddebug as a single human-readable line, with a
|
|
* special case for the header line.
|
|
*/
|
|
static int ddebug_proc_show(struct seq_file *m, void *p)
|
|
{
|
|
struct ddebug_iter *iter = m->private;
|
|
struct _ddebug *dp = p;
|
|
char flagsbuf[8];
|
|
|
|
if (verbose)
|
|
printk(KERN_INFO "%s: called m=%p p=%p\n",
|
|
__func__, m, p);
|
|
|
|
if (p == SEQ_START_TOKEN) {
|
|
seq_puts(m,
|
|
"# filename:lineno [module]function flags format\n");
|
|
return 0;
|
|
}
|
|
|
|
seq_printf(m, "%s:%u [%s]%s %s \"",
|
|
dp->filename, dp->lineno,
|
|
iter->table->mod_name, dp->function,
|
|
ddebug_describe_flags(dp, flagsbuf, sizeof(flagsbuf)));
|
|
seq_escape(m, dp->format, "\t\r\n\"");
|
|
seq_puts(m, "\"\n");
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Seq_ops stop method. Called at the end of each read()
|
|
* call from userspace. Drops ddebug_lock.
|
|
*/
|
|
static void ddebug_proc_stop(struct seq_file *m, void *p)
|
|
{
|
|
if (verbose)
|
|
printk(KERN_INFO "%s: called m=%p p=%p\n",
|
|
__func__, m, p);
|
|
mutex_unlock(&ddebug_lock);
|
|
}
|
|
|
|
static const struct seq_operations ddebug_proc_seqops = {
|
|
.start = ddebug_proc_start,
|
|
.next = ddebug_proc_next,
|
|
.show = ddebug_proc_show,
|
|
.stop = ddebug_proc_stop
|
|
};
|
|
|
|
/*
|
|
* File_ops->open method for <debugfs>/dynamic_debug/control. Does the seq_file
|
|
* setup dance, and also creates an iterator to walk the _ddebugs.
|
|
* Note that we create a seq_file always, even for O_WRONLY files
|
|
* where it's not needed, as doing so simplifies the ->release method.
|
|
*/
|
|
static int ddebug_proc_open(struct inode *inode, struct file *file)
|
|
{
|
|
struct ddebug_iter *iter;
|
|
int err;
|
|
|
|
if (verbose)
|
|
printk(KERN_INFO "%s: called\n", __func__);
|
|
|
|
iter = kzalloc(sizeof(*iter), GFP_KERNEL);
|
|
if (iter == NULL)
|
|
return -ENOMEM;
|
|
|
|
err = seq_open(file, &ddebug_proc_seqops);
|
|
if (err) {
|
|
kfree(iter);
|
|
return err;
|
|
}
|
|
((struct seq_file *) file->private_data)->private = iter;
|
|
return 0;
|
|
}
|
|
|
|
static const struct file_operations ddebug_proc_fops = {
|
|
.owner = THIS_MODULE,
|
|
.open = ddebug_proc_open,
|
|
.read = seq_read,
|
|
.llseek = seq_lseek,
|
|
.release = seq_release_private,
|
|
.write = ddebug_proc_write
|
|
};
|
|
|
|
/*
|
|
* Allocate a new ddebug_table for the given module
|
|
* and add it to the global list.
|
|
*/
|
|
int ddebug_add_module(struct _ddebug *tab, unsigned int n,
|
|
const char *name)
|
|
{
|
|
struct ddebug_table *dt;
|
|
char *new_name;
|
|
|
|
dt = kzalloc(sizeof(*dt), GFP_KERNEL);
|
|
if (dt == NULL)
|
|
return -ENOMEM;
|
|
new_name = kstrdup(name, GFP_KERNEL);
|
|
if (new_name == NULL) {
|
|
kfree(dt);
|
|
return -ENOMEM;
|
|
}
|
|
dt->mod_name = new_name;
|
|
dt->num_ddebugs = n;
|
|
dt->num_enabled = 0;
|
|
dt->ddebugs = tab;
|
|
|
|
mutex_lock(&ddebug_lock);
|
|
list_add_tail(&dt->link, &ddebug_tables);
|
|
mutex_unlock(&ddebug_lock);
|
|
|
|
if (verbose)
|
|
printk(KERN_INFO "%u debug prints in module %s\n",
|
|
n, dt->mod_name);
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(ddebug_add_module);
|
|
|
|
static void ddebug_table_free(struct ddebug_table *dt)
|
|
{
|
|
list_del_init(&dt->link);
|
|
kfree(dt->mod_name);
|
|
kfree(dt);
|
|
}
|
|
|
|
/*
|
|
* Called in response to a module being unloaded. Removes
|
|
* any ddebug_table's which point at the module.
|
|
*/
|
|
int ddebug_remove_module(const char *mod_name)
|
|
{
|
|
struct ddebug_table *dt, *nextdt;
|
|
int ret = -ENOENT;
|
|
|
|
if (verbose)
|
|
printk(KERN_INFO "%s: removing module \"%s\"\n",
|
|
__func__, mod_name);
|
|
|
|
mutex_lock(&ddebug_lock);
|
|
list_for_each_entry_safe(dt, nextdt, &ddebug_tables, link) {
|
|
if (!strcmp(dt->mod_name, mod_name)) {
|
|
ddebug_table_free(dt);
|
|
ret = 0;
|
|
}
|
|
}
|
|
mutex_unlock(&ddebug_lock);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(ddebug_remove_module);
|
|
|
|
static void ddebug_remove_all_tables(void)
|
|
{
|
|
mutex_lock(&ddebug_lock);
|
|
while (!list_empty(&ddebug_tables)) {
|
|
struct ddebug_table *dt = list_entry(ddebug_tables.next,
|
|
struct ddebug_table,
|
|
link);
|
|
ddebug_table_free(dt);
|
|
}
|
|
mutex_unlock(&ddebug_lock);
|
|
}
|
|
|
|
static __initdata int ddebug_init_success;
|
|
|
|
static int __init dynamic_debug_init_debugfs(void)
|
|
{
|
|
struct dentry *dir, *file;
|
|
|
|
if (!ddebug_init_success)
|
|
return -ENODEV;
|
|
|
|
dir = debugfs_create_dir("dynamic_debug", NULL);
|
|
if (!dir)
|
|
return -ENOMEM;
|
|
file = debugfs_create_file("control", 0644, dir, NULL,
|
|
&ddebug_proc_fops);
|
|
if (!file) {
|
|
debugfs_remove(dir);
|
|
return -ENOMEM;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int __init dynamic_debug_init(void)
|
|
{
|
|
struct _ddebug *iter, *iter_start;
|
|
const char *modname = NULL;
|
|
int ret = 0;
|
|
int n = 0;
|
|
|
|
if (__start___verbose != __stop___verbose) {
|
|
iter = __start___verbose;
|
|
modname = iter->modname;
|
|
iter_start = iter;
|
|
for (; iter < __stop___verbose; iter++) {
|
|
if (strcmp(modname, iter->modname)) {
|
|
ret = ddebug_add_module(iter_start, n, modname);
|
|
if (ret)
|
|
goto out_free;
|
|
n = 0;
|
|
modname = iter->modname;
|
|
iter_start = iter;
|
|
}
|
|
n++;
|
|
}
|
|
ret = ddebug_add_module(iter_start, n, modname);
|
|
}
|
|
|
|
/* ddebug_query boot param got passed -> set it up */
|
|
if (ddebug_setup_string[0] != '\0') {
|
|
ret = ddebug_exec_query(ddebug_setup_string);
|
|
if (ret)
|
|
pr_warning("Invalid ddebug boot param %s",
|
|
ddebug_setup_string);
|
|
else
|
|
pr_info("ddebug initialized with string %s",
|
|
ddebug_setup_string);
|
|
}
|
|
|
|
out_free:
|
|
if (ret)
|
|
ddebug_remove_all_tables();
|
|
else
|
|
ddebug_init_success = 1;
|
|
return 0;
|
|
}
|
|
/* Allow early initialization for boot messages via boot param */
|
|
arch_initcall(dynamic_debug_init);
|
|
/* Debugfs setup must be done later */
|
|
module_init(dynamic_debug_init_debugfs);
|