tracing: Create seq_buf layer in trace_seq

Create a seq_buf layer that trace_seq sits on. The seq_buf will not
be limited to page size. This will allow other usages of seq_buf
instead of a hard set PAGE_SIZE one that trace_seq has.

Link: http://lkml.kernel.org/r/20141104160221.864997179@goodmis.org
Link: http://lkml.kernel.org/r/20141114011412.170377300@goodmis.org

Tested-by: Jiri Kosina <jkosina@suse.cz>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Reviewed-by: Petr Mladek <pmladek@suse.cz>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 3 insertions, 3 deletions

diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index f9d0cbe..4d0067d 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -1044,7 +1044,7 @@ event_filter_read(struct file *filp, char __user *ubuf, size_t cnt,
 	mutex_unlock(&event_mutex);
 
 	if (file)
-		r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len);
+		r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->seq.len);
 
 	kfree(s);
 
@@ -1210,7 +1210,7 @@ subsystem_filter_read(struct file *filp, char __user *ubuf, size_t cnt,
 	trace_seq_init(s);
 
 	print_subsystem_event_filter(system, s);
-	r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len);
+	r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->seq.len);
 
 	kfree(s);
 
@@ -1265,7 +1265,7 @@ show_header(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos)
 	trace_seq_init(s);
 
 	func(s);
-	r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len);
+	r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->seq.len);
 
 	kfree(s);