ftrace: Clarify code for mod command

"Not" is too abstract variable name - changed to clear_filter.
Removed ftrace_match_module_records function: comparison with !* or *
not does the general code in filter_parse_regex() as it works without
mod command for
  sh# echo '!*' > /sys/kernel/debug/tracing/set_ftrace_filter

Link: http://lkml.kernel.org/r/1443545176-3215-2-git-send-email-0x7f454c46@gmail.com
Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 8892b45b436873068148b99b64f7c93759d45f88..fc755a49704f47c6be5e0db59ffe437f8a9641e1 100644 (file)
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -3454,13 +3454,13 @@ static int ftrace_match(char *str, char *regex, int len, int type)
 }
 
 static int
-enter_record(struct ftrace_hash *hash, struct dyn_ftrace *rec, int not)
+enter_record(struct ftrace_hash *hash, struct dyn_ftrace *rec, int clear_filter)
 {
        struct ftrace_func_entry *entry;
        int ret = 0;
 
        entry = ftrace_lookup_ip(hash, rec->ip);
-       if (not) {
+       if (clear_filter) {
                /* Do nothing if it doesn't exist */
                if (!entry)
                        return 0;
@@ -3499,8 +3499,7 @@ ftrace_match_record(struct dyn_ftrace *rec, char *mod,
 }
 
 static int
-match_records(struct ftrace_hash *hash, char *buff,
-             int len, char *mod, int not)
+match_records(struct ftrace_hash *hash, char *buff, int len, char *mod)
 {
        unsigned search_len = 0;
        struct ftrace_page *pg;
@@ -3509,9 +3508,10 @@ match_records(struct ftrace_hash *hash, char *buff,
        char *search = buff;
        int found = 0;
        int ret;
+       int clear_filter;
 
        if (len) {
-               type = filter_parse_regex(buff, len, &search, &not);
+               type = filter_parse_regex(buff, len, &search, &clear_filter);
                search_len = strlen(search);
        }
 
@@ -3522,7 +3522,7 @@ match_records(struct ftrace_hash *hash, char *buff,
 
        do_for_each_ftrace_rec(pg, rec) {
                if (ftrace_match_record(rec, mod, search, search_len, type)) {
-                       ret = enter_record(hash, rec, not);
+                       ret = enter_record(hash, rec, clear_filter);
                        if (ret < 0) {
                                found = ret;
                                goto out_unlock;
@@ -3539,26 +3539,9 @@ match_records(struct ftrace_hash *hash, char *buff,
 static int
 ftrace_match_records(struct ftrace_hash *hash, char *buff, int len)
 {
-       return match_records(hash, buff, len, NULL, 0);
+       return match_records(hash, buff, len, NULL);
 }
 
-static int
-ftrace_match_module_records(struct ftrace_hash *hash, char *buff, char *mod)
-{
-       int not = 0;
-
-       /* blank or '*' mean the same */
-       if (strcmp(buff, "*") == 0)
-               buff[0] = 0;
-
-       /* handle the case of 'dont filter this module' */
-       if (strcmp(buff, "!") == 0 || strcmp(buff, "!*") == 0) {
-               buff[0] = 0;
-               not = 1;
-       }
-
-       return match_records(hash, buff, strlen(buff), mod, not);
-}
 
 /*
  * We register the module command as a template to show others how
@@ -3567,7 +3550,7 @@ ftrace_match_module_records(struct ftrace_hash *hash, char *buff, char *mod)
 
 static int
 ftrace_mod_callback(struct ftrace_hash *hash,
-                   char *func, char *cmd, char *param, int enable)
+                   char *func, char *cmd, char *module, int enable)
 {
        int ret;
 
@@ -3580,10 +3563,10 @@ ftrace_mod_callback(struct ftrace_hash *hash,
         */
 
        /* we must have a module name */
-       if (!param || !strlen(param))
+       if (!module || !strlen(module))
                return -EINVAL;
 
-       ret = ftrace_match_module_records(hash, func, param);
+       ret = match_records(hash, func, strlen(func), module);
        if (!ret)
                return -EINVAL;
        if (ret < 0)