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Subject[RFC][PATCH 11/11] tracing: Have the document reflect that the trace file keeps tracing enabled
From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

Now that reading the trace file does not temporarly stop tracing while it is
open, update the document to reflect this fact.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
Documentation/trace/ftrace.rst | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/Documentation/trace/ftrace.rst b/Documentation/trace/ftrace.rst
index 99a0890e20ec..86e76f2a40dc 100644
--- a/Documentation/trace/ftrace.rst
+++ b/Documentation/trace/ftrace.rst
@@ -125,10 +125,13 @@ of ftrace. Here is a list of some of the key files:
trace:

This file holds the output of the trace in a human
- readable format (described below). Note, tracing is temporarily
- disabled when the file is open for reading. Once all readers
- are closed, tracing is re-enabled. Opening this file for
+ readable format (described below). Opening this file for
writing with the O_TRUNC flag clears the ring buffer content.
+ Note, this file is not a consumer. If tracing is off
+ (no tracer running, or tracing_on is zero), it will produce
+ the same output each time it is read. When tracing is on,
+ it may produce inconsistent results as it tries to read
+ the entire buffer without consuming it.

trace_pipe:

@@ -142,9 +145,7 @@ of ftrace. Here is a list of some of the key files:
will not be read again with a sequential read. The
"trace" file is static, and if the tracer is not
adding more data, it will display the same
- information every time it is read. Unlike the
- "trace" file, opening this file for reading will not
- temporarily disable tracing.
+ information every time it is read.

trace_options:

--
2.25.1

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