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@@ -0,0 +1,756 @@
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+/*
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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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+ */
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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/uaccess.h>
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+#include <linux/dynamic_debug.h>
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+#include <linux/debugfs.h>
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+
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+extern struct _ddebug __start___verbose[];
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+extern struct _ddebug __stop___verbose[];
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+
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+/* dynamic_debug_enabled, and dynamic_debug_enabled2 are bitmasks in which
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+ * bit n is set to 1 if any modname hashes into the bucket n, 0 otherwise. They
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+ * use independent hash functions, to reduce the chance of false positives.
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+ */
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+long long dynamic_debug_enabled;
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+EXPORT_SYMBOL_GPL(dynamic_debug_enabled);
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+long long dynamic_debug_enabled2;
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+EXPORT_SYMBOL_GPL(dynamic_debug_enabled2);
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+
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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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+
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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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+
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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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+
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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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+
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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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+
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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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+
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+ BUG_ON(maxlen < 4);
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+ if (dp->flags & _DPRINTK_FLAGS_PRINT)
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+ *p++ = 'p';
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+ if (p == buf)
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+ *p++ = '-';
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+ *p = '\0';
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+
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+ return buf;
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+}
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+
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+/*
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+ * must be called with ddebug_lock held
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+ */
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+
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+static int disabled_hash(char hash, bool first_table)
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+{
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+ struct ddebug_table *dt;
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+ char table_hash_value;
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+
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+ list_for_each_entry(dt, &ddebug_tables, link) {
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+ if (first_table)
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+ table_hash_value = dt->ddebugs->primary_hash;
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+ else
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+ table_hash_value = dt->ddebugs->secondary_hash;
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+ if (dt->num_enabled && (hash == table_hash_value))
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+ return 0;
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+ }
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+ return 1;
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+}
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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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+
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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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+
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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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+
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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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+
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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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+
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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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+
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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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+
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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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+
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+ nfound++;
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+
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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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+
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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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+ dynamic_debug_enabled |=
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+ (1LL << dp->primary_hash);
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+ dynamic_debug_enabled2 |=
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+ (1LL << dp->secondary_hash);
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+ } else {
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+ if (disabled_hash(dp->primary_hash, true))
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+ dynamic_debug_enabled &=
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+ ~(1LL << dp->primary_hash);
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+ if (disabled_hash(dp->secondary_hash, false))
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+ dynamic_debug_enabled2 &=
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+ ~(1LL << dp->secondary_hash);
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+ }
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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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+
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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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+/*
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+ * Wrapper around strsep() to collapse the multiple empty tokens
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+ * that it returns when fed sequences of separator characters.
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+ * Now, if we had strtok_r()...
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+ */
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+static inline char *nearly_strtok_r(char **p, const char *sep)
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+{
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+ char *r;
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+
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+ while ((r = strsep(p, sep)) != NULL && *r == '\0')
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+ ;
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+ return r;
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+}
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+
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+/*
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+ * Split the buffer `buf' into space-separated words.
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+ * Return the number of such words 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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+
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+ while (nwords < maxwords &&
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+ (words[nwords] = nearly_strtok_r(&buf, " \t\r\n")) != NULL)
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+ nwords++;
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+ if (buf)
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+ return -EINVAL; /* ran out of words[] before bytes */
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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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+
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+ return nwords;
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+}
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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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+/*
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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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+
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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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+
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+ return str;
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+}
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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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+
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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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+
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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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+
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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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+
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+ return 0;
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+}
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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 = '=';
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+
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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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+
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+ for ( ; *str ; ++str) {
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+ switch (*str) {
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+ case 'p':
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+ flags |= _DPRINTK_FLAGS_PRINT;
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+ break;
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+ default:
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+ return -EINVAL;
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+ }
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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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+
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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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+
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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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+ */
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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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+{
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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];
|
|
|
+ char tmpbuf[256];
|
|
|
+
|
|
|
+ if (len == 0)
|
|
|
+ return 0;
|
|
|
+ /* we don't check *offp -- multiple writes() are allowed */
|
|
|
+ if (len > sizeof(tmpbuf)-1)
|
|
|
+ return -E2BIG;
|
|
|
+ if (copy_from_user(tmpbuf, ubuf, len))
|
|
|
+ return -EFAULT;
|
|
|
+ tmpbuf[len] = '\0';
|
|
|
+ if (verbose)
|
|
|
+ printk(KERN_INFO "%s: read %d bytes from userspace\n",
|
|
|
+ __func__, (int)len);
|
|
|
+
|
|
|
+ nwords = ddebug_tokenize(tmpbuf, words, MAXWORDS);
|
|
|
+ if (nwords < 0)
|
|
|
+ return -EINVAL;
|
|
|
+ if (ddebug_parse_query(words, nwords-1, &query))
|
|
|
+ return -EINVAL;
|
|
|
+ if (ddebug_parse_flags(words[nwords-1], &flags, &mask))
|
|
|
+ return -EINVAL;
|
|
|
+
|
|
|
+ /* actually go and implement the change */
|
|
|
+ ddebug_change(&query, flags, mask);
|
|
|
+
|
|
|
+ *offp += len;
|
|
|
+ return len;
|
|
|
+}
|
|
|
+
|
|
|
+/*
|
|
|
+ * Set the iterator to point to the first _ddebug object
|
|
|
+ * and return a pointer to that first object. Returns
|
|
|
+ * NULL if there are no _ddebugs at all.
|
|
|
+ */
|
|
|
+static struct _ddebug *ddebug_iter_first(struct ddebug_iter *iter)
|
|
|
+{
|
|
|
+ if (list_empty(&ddebug_tables)) {
|
|
|
+ iter->table = NULL;
|
|
|
+ iter->idx = 0;
|
|
|
+ return NULL;
|
|
|
+ }
|
|
|
+ iter->table = list_entry(ddebug_tables.next,
|
|
|
+ struct ddebug_table, link);
|
|
|
+ iter->idx = 0;
|
|
|
+ return &iter->table->ddebugs[iter->idx];
|
|
|
+}
|
|
|
+
|
|
|
+/*
|
|
|
+ * Advance the iterator to point to the next _ddebug
|
|
|
+ * object from the one the iterator currently points at,
|
|
|
+ * and returns a pointer to the new _ddebug. Returns
|
|
|
+ * NULL if the iterator has seen all the _ddebugs.
|
|
|
+ */
|
|
|
+static struct _ddebug *ddebug_iter_next(struct ddebug_iter *iter)
|
|
|
+{
|
|
|
+ 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(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 int __init dynamic_debug_init(void)
|
|
|
+{
|
|
|
+ struct dentry *dir, *file;
|
|
|
+ struct _ddebug *iter, *iter_start;
|
|
|
+ const char *modname = NULL;
|
|
|
+ int ret = 0;
|
|
|
+ int n = 0;
|
|
|
+
|
|
|
+ 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;
|
|
|
+ }
|
|
|
+ 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);
|
|
|
+ }
|
|
|
+out_free:
|
|
|
+ if (ret) {
|
|
|
+ ddebug_remove_all_tables();
|
|
|
+ debugfs_remove(dir);
|
|
|
+ debugfs_remove(file);
|
|
|
+ }
|
|
|
+ return 0;
|
|
|
+}
|
|
|
+module_init(dynamic_debug_init);
|
Jason Baron