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Diffstat (limited to 'lib/dynamic_debug.c')
-rw-r--r--lib/dynamic_debug.c190
1 files changed, 123 insertions, 67 deletions
diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index 310c753cf83e..7ca29a0a3019 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -107,20 +107,22 @@ static char *ddebug_describe_flags(struct _ddebug *dp, char *buf,
return buf;
}
-#define vpr_info_dq(q, msg) \
-do { \
- if (verbose) \
- /* trim last char off format print */ \
- pr_info("%s: func=\"%s\" file=\"%s\" " \
- "module=\"%s\" format=\"%.*s\" " \
- "lineno=%u-%u", \
- msg, \
- q->function ? q->function : "", \
- q->filename ? q->filename : "", \
- q->module ? q->module : "", \
- (int)(q->format ? strlen(q->format) - 1 : 0), \
- q->format ? q->format : "", \
- q->first_lineno, q->last_lineno); \
+#define vpr_info(fmt, ...) \
+ if (verbose) do { pr_info(fmt, ##__VA_ARGS__); } while (0)
+
+#define vpr_info_dq(q, msg) \
+do { \
+ /* trim last char off format print */ \
+ vpr_info("%s: func=\"%s\" file=\"%s\" " \
+ "module=\"%s\" format=\"%.*s\" " \
+ "lineno=%u-%u", \
+ msg, \
+ q->function ? q->function : "", \
+ q->filename ? q->filename : "", \
+ q->module ? q->module : "", \
+ (int)(q->format ? strlen(q->format) - 1 : 0), \
+ q->format ? q->format : "", \
+ q->first_lineno, q->last_lineno); \
} while (0)
/*
@@ -180,12 +182,11 @@ static int ddebug_change(const struct ddebug_query *query,
if (newflags == dp->flags)
continue;
dp->flags = newflags;
- if (verbose)
- pr_info("changed %s:%d [%s]%s =%s\n",
- trim_prefix(dp->filename), dp->lineno,
- dt->mod_name, dp->function,
- ddebug_describe_flags(dp, flagbuf,
- sizeof(flagbuf)));
+ vpr_info("changed %s:%d [%s]%s =%s\n",
+ trim_prefix(dp->filename), dp->lineno,
+ dt->mod_name, dp->function,
+ ddebug_describe_flags(dp, flagbuf,
+ sizeof(flagbuf)));
}
}
mutex_unlock(&ddebug_lock);
@@ -337,7 +338,7 @@ static int check_set(const char **dest, char *src, char *name)
* Returns 0 on success, <0 on error.
*/
static int ddebug_parse_query(char *words[], int nwords,
- struct ddebug_query *query)
+ struct ddebug_query *query, const char *modname)
{
unsigned int i;
int rc;
@@ -347,6 +348,10 @@ static int ddebug_parse_query(char *words[], int nwords,
return -EINVAL;
memset(query, 0, sizeof(*query));
+ if (modname)
+ /* support $modname.dyndbg=<multiple queries> */
+ query->module = modname;
+
for (i = 0 ; i < nwords ; i += 2) {
if (!strcmp(words[i], "func"))
rc = check_set(&query->function, words[i+1], "func");
@@ -410,8 +415,7 @@ static int ddebug_parse_flags(const char *str, unsigned int *flagsp,
default:
return -EINVAL;
}
- if (verbose)
- pr_info("op='%c'\n", op);
+ vpr_info("op='%c'\n", op);
for ( ; *str ; ++str) {
for (i = ARRAY_SIZE(opt_array) - 1; i >= 0; i--) {
@@ -423,8 +427,7 @@ static int ddebug_parse_flags(const char *str, unsigned int *flagsp,
if (i < 0)
return -EINVAL;
}
- if (verbose)
- pr_info("flags=0x%x\n", flags);
+ vpr_info("flags=0x%x\n", flags);
/* calculate final *flagsp, *maskp according to mask and op */
switch (op) {
@@ -441,12 +444,11 @@ static int ddebug_parse_flags(const char *str, unsigned int *flagsp,
*flagsp = 0;
break;
}
- if (verbose)
- pr_info("*flagsp=0x%x *maskp=0x%x\n", *flagsp, *maskp);
+ vpr_info("*flagsp=0x%x *maskp=0x%x\n", *flagsp, *maskp);
return 0;
}
-static int ddebug_exec_query(char *query_string)
+static int ddebug_exec_query(char *query_string, const char *modname)
{
unsigned int flags = 0, mask = 0;
struct ddebug_query query;
@@ -457,7 +459,7 @@ static int ddebug_exec_query(char *query_string)
nwords = ddebug_tokenize(query_string, words, MAXWORDS);
if (nwords <= 0)
return -EINVAL;
- if (ddebug_parse_query(words, nwords-1, &query))
+ if (ddebug_parse_query(words, nwords-1, &query, modname))
return -EINVAL;
if (ddebug_parse_flags(words[nwords-1], &flags, &mask))
return -EINVAL;
@@ -473,7 +475,7 @@ static int ddebug_exec_query(char *query_string)
last error or number of matching callsites. Module name is either
in param (for boot arg) or perhaps in query string.
*/
-static int ddebug_exec_queries(char *query)
+static int ddebug_exec_queries(char *query, const char *modname)
{
char *split;
int i, errs = 0, exitcode = 0, rc, nfound = 0;
@@ -487,10 +489,9 @@ static int ddebug_exec_queries(char *query)
if (!query || !*query || *query == '#')
continue;
- if (verbose)
- pr_info("query %d: \"%s\"\n", i, query);
+ vpr_info("query %d: \"%s\"\n", i, query);
- rc = ddebug_exec_query(query);
+ rc = ddebug_exec_query(query, modname);
if (rc < 0) {
errs++;
exitcode = rc;
@@ -498,7 +499,7 @@ static int ddebug_exec_queries(char *query)
nfound += rc;
i++;
}
- pr_info("processed %d queries, with %d matches, %d errs\n",
+ vpr_info("processed %d queries, with %d matches, %d errs\n",
i, nfound, errs);
if (exitcode)
@@ -653,10 +654,9 @@ static ssize_t ddebug_proc_write(struct file *file, const char __user *ubuf,
return -EFAULT;
}
tmpbuf[len] = '\0';
- if (verbose)
- pr_info("read %d bytes from userspace\n", (int)len);
+ vpr_info("read %d bytes from userspace\n", (int)len);
- ret = ddebug_exec_queries(tmpbuf);
+ ret = ddebug_exec_queries(tmpbuf, NULL);
kfree(tmpbuf);
if (ret < 0)
return ret;
@@ -717,8 +717,7 @@ static void *ddebug_proc_start(struct seq_file *m, loff_t *pos)
struct _ddebug *dp;
int n = *pos;
- if (verbose)
- pr_info("called m=%p *pos=%lld\n", m, (unsigned long long)*pos);
+ vpr_info("called m=%p *pos=%lld\n", m, (unsigned long long)*pos);
mutex_lock(&ddebug_lock);
@@ -742,9 +741,8 @@ 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)
- pr_info("called m=%p p=%p *pos=%lld\n",
- m, p, (unsigned long long)*pos);
+ vpr_info("called m=%p p=%p *pos=%lld\n",
+ m, p, (unsigned long long)*pos);
if (p == SEQ_START_TOKEN)
dp = ddebug_iter_first(iter);
@@ -766,8 +764,7 @@ static int ddebug_proc_show(struct seq_file *m, void *p)
struct _ddebug *dp = p;
char flagsbuf[10];
- if (verbose)
- pr_info("called m=%p p=%p\n", m, p);
+ vpr_info("called m=%p p=%p\n", m, p);
if (p == SEQ_START_TOKEN) {
seq_puts(m,
@@ -791,8 +788,7 @@ static int ddebug_proc_show(struct seq_file *m, void *p)
*/
static void ddebug_proc_stop(struct seq_file *m, void *p)
{
- if (verbose)
- pr_info("called m=%p p=%p\n", m, p);
+ vpr_info("called m=%p p=%p\n", m, p);
mutex_unlock(&ddebug_lock);
}
@@ -815,8 +811,7 @@ static int ddebug_proc_open(struct inode *inode, struct file *file)
struct ddebug_iter *iter;
int err;
- if (verbose)
- pr_info("called\n");
+ vpr_info("called\n");
iter = kzalloc(sizeof(*iter), GFP_KERNEL);
if (iter == NULL)
@@ -866,12 +861,51 @@ int ddebug_add_module(struct _ddebug *tab, unsigned int n,
list_add_tail(&dt->link, &ddebug_tables);
mutex_unlock(&ddebug_lock);
- if (verbose)
- pr_info("%u debug prints in module %s\n", n, dt->mod_name);
+ vpr_info("%u debug prints in module %s\n", n, dt->mod_name);
return 0;
}
EXPORT_SYMBOL_GPL(ddebug_add_module);
+/* helper for ddebug_dyndbg_(boot|module)_param_cb */
+static int ddebug_dyndbg_param_cb(char *param, char *val,
+ const char *modname, int on_err)
+{
+ char *sep;
+
+ sep = strchr(param, '.');
+ if (sep) {
+ /* needed only for ddebug_dyndbg_boot_param_cb */
+ *sep = '\0';
+ modname = param;
+ param = sep + 1;
+ }
+ if (strcmp(param, "dyndbg"))
+ return on_err; /* determined by caller */
+
+ ddebug_exec_queries((val ? val : "+p"), modname);
+
+ return 0; /* query failure shouldnt stop module load */
+}
+
+/* handle both dyndbg and $module.dyndbg params at boot */
+static int ddebug_dyndbg_boot_param_cb(char *param, char *val,
+ const char *unused)
+{
+ vpr_info("%s=\"%s\"\n", param, val);
+ return ddebug_dyndbg_param_cb(param, val, NULL, 0);
+}
+
+/*
+ * modprobe foo finds foo.params in boot-args, strips "foo.", and
+ * passes them to load_module(). This callback gets unknown params,
+ * processes dyndbg params, rejects others.
+ */
+int ddebug_dyndbg_module_param_cb(char *param, char *val, const char *module)
+{
+ vpr_info("module: %s %s=\"%s\"\n", module, param, val);
+ return ddebug_dyndbg_param_cb(param, val, module, -ENOENT);
+}
+
static void ddebug_table_free(struct ddebug_table *dt)
{
list_del_init(&dt->link);
@@ -888,8 +922,7 @@ int ddebug_remove_module(const char *mod_name)
struct ddebug_table *dt, *nextdt;
int ret = -ENOENT;
- if (verbose)
- pr_info("removing module \"%s\"\n", mod_name);
+ vpr_info("removing module \"%s\"\n", mod_name);
mutex_lock(&ddebug_lock);
list_for_each_entry_safe(dt, nextdt, &ddebug_tables, link) {
@@ -940,8 +973,10 @@ static int __init dynamic_debug_init(void)
{
struct _ddebug *iter, *iter_start;
const char *modname = NULL;
+ char *cmdline;
int ret = 0;
- int n = 0;
+ int n = 0, entries = 0, modct = 0;
+ int verbose_bytes = 0;
if (__start___verbose == __stop___verbose) {
pr_warn("_ddebug table is empty in a "
@@ -952,10 +987,15 @@ static int __init dynamic_debug_init(void)
modname = iter->modname;
iter_start = iter;
for (; iter < __stop___verbose; iter++) {
+ entries++;
+ verbose_bytes += strlen(iter->modname) + strlen(iter->function)
+ + strlen(iter->filename) + strlen(iter->format);
+
if (strcmp(modname, iter->modname)) {
+ modct++;
ret = ddebug_add_module(iter_start, n, modname);
if (ret)
- goto out_free;
+ goto out_err;
n = 0;
modname = iter->modname;
iter_start = iter;
@@ -964,29 +1004,45 @@ static int __init dynamic_debug_init(void)
}
ret = ddebug_add_module(iter_start, n, modname);
if (ret)
- goto out_free;
+ goto out_err;
+
+ ddebug_init_success = 1;
+ vpr_info("%d modules, %d entries and %d bytes in ddebug tables,"
+ " %d bytes in (readonly) verbose section\n",
+ modct, entries, (int)( modct * sizeof(struct ddebug_table)),
+ verbose_bytes + (int)(__stop___verbose - __start___verbose));
- /* ddebug_query boot param got passed -> set it up */
+ /* apply ddebug_query boot param, dont unload tables on err */
if (ddebug_setup_string[0] != '\0') {
- ret = ddebug_exec_queries(ddebug_setup_string);
+ pr_warn("ddebug_query param name is deprecated,"
+ " change it to dyndbg\n");
+ ret = ddebug_exec_queries(ddebug_setup_string, NULL);
if (ret < 0)
pr_warn("Invalid ddebug boot param %s",
ddebug_setup_string);
else
pr_info("%d changes by ddebug_query\n", ret);
-
- /* keep tables even on ddebug_query parse error */
- ret = 0;
}
+ /* now that ddebug tables are loaded, process all boot args
+ * again to find and activate queries given in dyndbg params.
+ * While this has already been done for known boot params, it
+ * ignored the unknown ones (dyndbg in particular). Reusing
+ * parse_args avoids ad-hoc parsing. This will also attempt
+ * to activate queries for not-yet-loaded modules, which is
+ * slightly noisy if verbose, but harmless.
+ */
+ cmdline = kstrdup(saved_command_line, GFP_KERNEL);
+ parse_args("dyndbg params", cmdline, NULL,
+ 0, 0, 0, &ddebug_dyndbg_boot_param_cb);
+ kfree(cmdline);
+ return 0;
-out_free:
- if (ret)
- ddebug_remove_all_tables();
- else
- ddebug_init_success = 1;
+out_err:
+ ddebug_remove_all_tables();
return 0;
}
/* Allow early initialization for boot messages via boot param */
-arch_initcall(dynamic_debug_init);
+early_initcall(dynamic_debug_init);
+
/* Debugfs setup must be done later */
-module_init(dynamic_debug_init_debugfs);
+fs_initcall(dynamic_debug_init_debugfs);
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.