tracing: trace parser support for function and graph

Convert the writing to 'set_graph_function', 'set_ftrace_filter'
and 'set_ftrace_notrace' to use the generic trace_parser
'trace_get_user' function.

Removed FTRACE_ITER_CONT flag, since it's not needed after this change.

Minor fix in set_graph_function display - g_show function.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
LKML-Reference: <1252682969-3366-4-git-send-email-jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 40 insertions, 110 deletions

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 8c804e24f96f..8b23d5670088 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1323,11 +1323,10 @@ static int __init ftrace_dyn_table_alloc(unsigned long num_to_init)
 
 enum {
         FTRACE_ITER_FILTER      = (1 << 0),
-        FTRACE_ITER_CONT        = (1 << 1),
-        FTRACE_ITER_NOTRACE     = (1 << 2),
-        FTRACE_ITER_FAILURES    = (1 << 3),
-        FTRACE_ITER_PRINTALL    = (1 << 4),
-        FTRACE_ITER_HASH        = (1 << 5),
+        FTRACE_ITER_NOTRACE     = (1 << 1),
+        FTRACE_ITER_FAILURES    = (1 << 2),
+        FTRACE_ITER_PRINTALL    = (1 << 3),
+        FTRACE_ITER_HASH        = (1 << 4),
 };
 
 #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */
@@ -1337,8 +1336,7 @@ struct ftrace_iterator {
         int                     hidx;
         int                     idx;
         unsigned                flags;
-        unsigned char           buffer[FTRACE_BUFF_MAX+1];
-        unsigned                buffer_idx;
+        struct trace_parser     parser;
 };
 
 static void *
@@ -1604,6 +1602,11 @@ ftrace_regex_open(struct inode *inode, struct file *file, int enable)
         if (!iter)
                 return -ENOMEM;
 
+        if (trace_parser_get_init(&iter->parser, FTRACE_BUFF_MAX)) {
+                kfree(iter);
+                return -ENOMEM;
+        }
+
         mutex_lock(&ftrace_regex_lock);
         if ((file->f_mode & FMODE_WRITE) &&
             (file->f_flags & O_TRUNC))
@@ -2196,9 +2199,8 @@ ftrace_regex_write(struct file *file, const char __user *ubuf,
                    size_t cnt, loff_t *ppos, int enable)
 {
         struct ftrace_iterator *iter;
-        char ch;
-        size_t read = 0;
-        ssize_t ret;
+        struct trace_parser *parser;
+        ssize_t ret, read;
 
         if (!cnt || cnt < 0)
                 return 0;
@@ -2211,72 +2213,23 @@ ftrace_regex_write(struct file *file, const char __user *ubuf,
         } else
                 iter = file->private_data;
 
-        if (!*ppos) {
-                iter->flags &= ~FTRACE_ITER_CONT;
-                iter->buffer_idx = 0;
-        }
-
-        ret = get_user(ch, ubuf++);
-        if (ret)
-                goto out;
-        read++;
-        cnt--;
-
-        /*
-         * If the parser haven't finished with the last write,
-         * continue reading the user input without skipping spaces.
-         */
-        if (!(iter->flags & FTRACE_ITER_CONT)) {
-                /* skip white space */
-                while (cnt && isspace(ch)) {
-                        ret = get_user(ch, ubuf++);
-                        if (ret)
-                                goto out;
-                        read++;
-                        cnt--;
-                }
+        parser = &iter->parser;
+        read = trace_get_user(parser, ubuf, cnt, ppos);
 
-                /* only spaces were written */
-                if (isspace(ch)) {
-                        *ppos += read;
-                        ret = read;
-                        goto out;
-                }
-
-                iter->buffer_idx = 0;
-        }
-
-        while (cnt && !isspace(ch)) {
-                if (iter->buffer_idx < FTRACE_BUFF_MAX)
-                        iter->buffer[iter->buffer_idx++] = ch;
-                else {
-                        ret = -EINVAL;
-                        goto out;
-                }
-                ret = get_user(ch, ubuf++);
+        if (trace_parser_loaded(parser) &&
+            !trace_parser_cont(parser)) {
+                ret = ftrace_process_regex(parser->buffer,
+                                           parser->idx, enable);
                 if (ret)
                         goto out;
-                read++;
-                cnt--;
-        }
 
-        if (isspace(ch)) {
-                iter->buffer[iter->buffer_idx] = 0;
-                ret = ftrace_process_regex(iter->buffer,
-                                           iter->buffer_idx, enable);
-                if (ret)
-                        goto out;
-                iter->buffer_idx = 0;
-        } else {
-                iter->flags |= FTRACE_ITER_CONT;
-                iter->buffer[iter->buffer_idx++] = ch;
+                trace_parser_clear(parser);
         }
 
-        *ppos += read;
         ret = read;
- out:
-        mutex_unlock(&ftrace_regex_lock);
 
+        mutex_unlock(&ftrace_regex_lock);
+out:
         return ret;
 }
 
@@ -2381,6 +2334,7 @@ ftrace_regex_release(struct inode *inode, struct file *file, int enable)
 {
         struct seq_file *m = (struct seq_file *)file->private_data;
         struct ftrace_iterator *iter;
+        struct trace_parser *parser;
 
         mutex_lock(&ftrace_regex_lock);
         if (file->f_mode & FMODE_READ) {
@@ -2390,9 +2344,10 @@ ftrace_regex_release(struct inode *inode, struct file *file, int enable)
         } else
                 iter = file->private_data;
 
-        if (iter->buffer_idx) {
-                iter->buffer[iter->buffer_idx] = 0;
-                ftrace_match_records(iter->buffer, iter->buffer_idx, enable);
+        parser = &iter->parser;
+        if (trace_parser_loaded(parser)) {
+                parser->buffer[parser->idx] = 0;
+                ftrace_match_records(parser->buffer, parser->idx, enable);
         }
 
         mutex_lock(&ftrace_lock);
@@ -2400,7 +2355,9 @@ ftrace_regex_release(struct inode *inode, struct file *file, int enable)
                 ftrace_run_update_code(FTRACE_ENABLE_CALLS);
         mutex_unlock(&ftrace_lock);
 
+        trace_parser_put(parser);
         kfree(iter);
+
         mutex_unlock(&ftrace_regex_lock);
         return 0;
 }
@@ -2499,7 +2456,7 @@ static int g_show(struct seq_file *m, void *v)
                 return 0;
         }
 
-        seq_printf(m, "%pf\n", v);
+        seq_printf(m, "%pf\n", (void *)*ptr);
 
         return 0;
 }
@@ -2602,12 +2559,10 @@ static ssize_t
 ftrace_graph_write(struct file *file, const char __user *ubuf,
                    size_t cnt, loff_t *ppos)
 {
-        unsigned char buffer[FTRACE_BUFF_MAX+1];
+        struct trace_parser parser;
         unsigned long *array;
         size_t read = 0;
         ssize_t ret;
-        int index = 0;
-        char ch;
 
         if (!cnt || cnt < 0)
                 return 0;
@@ -2625,51 +2580,26 @@ ftrace_graph_write(struct file *file, const char __user *ubuf,
         } else
                 array = file->private_data;
 
-        ret = get_user(ch, ubuf++);
-        if (ret)
+        if (trace_parser_get_init(&parser, FTRACE_BUFF_MAX)) {
+                ret = -ENOMEM;
                 goto out;
-        read++;
-        cnt--;
-
-        /* skip white space */
-        while (cnt && isspace(ch)) {
-                ret = get_user(ch, ubuf++);
-                if (ret)
-                        goto out;
-                read++;
-                cnt--;
         }
 
-        if (isspace(ch)) {
-                *ppos += read;
-                ret = read;
-                goto out;
-        }
+        read = trace_get_user(&parser, ubuf, cnt, ppos);
 
-        while (cnt && !isspace(ch)) {
-                if (index < FTRACE_BUFF_MAX)
-                        buffer[index++] = ch;
-                else {
-                        ret = -EINVAL;
-                        goto out;
-                }
-                ret = get_user(ch, ubuf++);
+        if (trace_parser_loaded((&parser))) {
+                parser.buffer[parser.idx] = 0;
+
+                /* we allow only one expression at a time */
+                ret = ftrace_set_func(array, &ftrace_graph_count,
+                                        parser.buffer);
                 if (ret)
                         goto out;
-                read++;
-                cnt--;
         }
-        buffer[index] = 0;
-
-        /* we allow only one expression at a time */
-        ret = ftrace_set_func(array, &ftrace_graph_count, buffer);
-        if (ret)
-                goto out;
-
-        file->f_pos += read;
 
         ret = read;
  out:
+        trace_parser_put(&parser);
         mutex_unlock(&graph_lock);
 
         return ret;