Merge remote-tracking branch 'regmap/fix/debugfs' into tmp

[karo-tx-linux.git] / kernel / trace / trace.c

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index e5125677efa007a8ff58d5cd14b70766117dbc92..3c13e46d7d24e1ecbdeb532f6538354f6eca7ddf 100644 (file)
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2899,6 +2899,8 @@ tracing_trace_options_write(struct file *filp, const char __user *ubuf,
        if (copy_from_user(&buf, ubuf, cnt))
                return -EFAULT;
 
+       buf[cnt] = 0;
+
        trace_set_options(buf);
 
        *ppos += cnt;
@@ -3452,7 +3454,7 @@ static int tracing_wait_pipe(struct file *filp)
                        return -EINTR;
 
                /*
-                * We block until we read something and tracing is enabled.
+                * We block until we read something and tracing is disabled.
                 * We still block if tracing is disabled, but we have never
                 * read anything. This allows a user to cat this file, and
                 * then enable tracing. But after we have read something,
@@ -3460,7 +3462,7 @@ static int tracing_wait_pipe(struct file *filp)
                 *
                 * iter->pos will be 0 if we haven't read anything.
                 */
-               if (tracing_is_enabled() && iter->pos)
+               if (!tracing_is_enabled() && iter->pos)
                        break;
        }
 
@@ -4815,10 +4817,17 @@ rb_simple_write(struct file *filp, const char __user *ubuf,
                return ret;
 
        if (buffer) {
-               if (val)
+               mutex_lock(&trace_types_lock);
+               if (val) {
                        ring_buffer_record_on(buffer);
-               else
+                       if (current_trace->start)
+                               current_trace->start(tr);
+               } else {
                        ring_buffer_record_off(buffer);
+                       if (current_trace->stop)
+                               current_trace->stop(tr);
+               }
+               mutex_unlock(&trace_types_lock);
        }
 
        (*ppos)++;