tracing: trace parser support for set_event

Convert the parsing of the file 'set_event' to use the generic
trace_praser 'trace_get_user' function.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
LKML-Reference: <1252682969-3366-3-git-send-email-jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 13 insertions, 47 deletions

diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 975f324a07e7..f46d14cefdec 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -230,11 +230,9 @@ static ssize_t
 ftrace_event_write(struct file *file, const char __user *ubuf,
                    size_t cnt, loff_t *ppos)
 {
+        struct trace_parser parser;
         size_t read = 0;
-        int i, set = 1;
         ssize_t ret;
-        char *buf;
-        char ch;
 
         if (!cnt || cnt < 0)
                 return 0;
@@ -243,60 +241,28 @@ ftrace_event_write(struct file *file, const char __user *ubuf,
         if (ret < 0)
                 return ret;
 
-        ret = get_user(ch, ubuf++);
-        if (ret)
-                return ret;
-        read++;
-        cnt--;
-
-        /* skip white space */
-        while (cnt && isspace(ch)) {
-                ret = get_user(ch, ubuf++);
-                if (ret)
-                        return ret;
-                read++;
-                cnt--;
-        }
-
-        /* Only white space found? */
-        if (isspace(ch)) {
-                file->f_pos += read;
-                ret = read;
-                return ret;
-        }
-
-        buf = kmalloc(EVENT_BUF_SIZE+1, GFP_KERNEL);
-        if (!buf)
+        if (trace_parser_get_init(&parser, EVENT_BUF_SIZE + 1))
                 return -ENOMEM;
 
-        if (cnt > EVENT_BUF_SIZE)
-                cnt = EVENT_BUF_SIZE;
+        read = trace_get_user(&parser, ubuf, cnt, ppos);
+
+        if (trace_parser_loaded((&parser))) {
+                int set = 1;
 
-        i = 0;
-        while (cnt && !isspace(ch)) {
-                if (!i && ch == '!')
+                if (*parser.buffer == '!')
                         set = 0;
-                else
-                        buf[i++] = ch;
 
-                ret = get_user(ch, ubuf++);
+                parser.buffer[parser.idx] = 0;
+
+                ret = ftrace_set_clr_event(parser.buffer + !set, set);
                 if (ret)
-                        goto out_free;
-                read++;
-                cnt--;
+                        goto out_put;
         }
-        buf[i] = 0;
-
-        file->f_pos += read;
-
-        ret = ftrace_set_clr_event(buf, set);
-        if (ret)
-                goto out_free;
 
         ret = read;
 
- out_free:
-        kfree(buf);
+ out_put:
+        trace_parser_put(&parser);
 
         return ret;
 }