[PATCHv2 3/3] tracing - buf iterator support for set_graph_function set_ftrace_filter set_ftrace_notrace

jolsa
2009-09-05T01:13:21Z

Updated 'set_graph_function', 'set_ftrace_filter', 'set_ftrace_notrace' write methods
to use the 'trace_get_user' function.

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

Fixed minor in set_graph_function display - g_show function.

wbr,
jirka

Signed-off-by: Jiri Olsa <jolsa@redhat.com>

---
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 8c804e2..04bffba 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_biter biter;
};

static void *
@@ -1604,6 +1602,11 @@ ftrace_regex_open(struct inode *inode, struct file *file, int enable)
if (!iter)
return -ENOMEM;

+ if (trace_biter_alloc(&iter->biter, 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_biter *biter;
+ 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--;
+ biter = &iter->biter;
+ read = trace_get_user(biter, ubuf, cnt, ppos);

- /*
- * 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--;
- }
-
- /* 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_BITER_LOADED(biter) &&
+ !TRACE_BITER_CONT(biter)) {
+ ret = ftrace_process_regex(biter->buffer,
+ biter->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_BITER_CLEAR(biter);
}

- *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_biter *biter;

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);
+ biter = &iter->biter;
+ if (TRACE_BITER_LOADED(biter)) {
+ biter->buffer[biter->idx] = 0;
+ ftrace_match_records(biter->buffer, biter->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_biter_free(biter);
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, "%p\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_biter biter;
unsigned long *array;
size_t read = 0;
ssize_t ret;
- int index = 0;
- char ch;

if (!cnt || cnt < 0)
return 0;
@@ -2625,51 +2580,27 @@ ftrace_graph_write(struct file *file, const char __user *ubuf,
} else
array = file->private_data;

- ret = get_user(ch, ubuf++);
- if (ret)
+ if (trace_biter_alloc(&biter, 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(&biter, ubuf, cnt, ppos);
+
+ if (TRACE_BITER_LOADED((&biter))) {
+ biter.buffer[biter.idx] = 0;
+
+ /* we allow only one expression at a time */
+ ret = ftrace_set_func(array, &ftrace_graph_count,
+ biter.buffer);

- while (cnt && !isspace(ch)) {
- if (index < FTRACE_BUFF_MAX)
- buffer[index++] = ch;
- else {
- ret = -EINVAL;
- goto out;
- }
- ret = get_user(ch, ubuf++);
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_biter_free(&biter);
mutex_unlock(&graph_lock);

return ret;