tracing: fix ref count in splice pages

The pages allocated for the splice binary buffer did not initialize
the ref count correctly. This caused pages not to be freed and causes
a drastic memory leak.

Thanks to logdev I was able to trace the tracer to find where the leak
was.

[ Impact: stop memory leak when using splice ]

Signed-off-by: Steven Rostedt <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>

kernel/trace/trace.c

@@ -3448,6 +3448,7 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
 		if (!ref)
 			break;
 
+		ref->ref = 1;
 		ref->buffer = info->tr->buffer;
 		ref->page = ring_buffer_alloc_read_page(ref->buffer);
 		if (!ref->page) {