tracing: Have the document reflect that the trace file keeps tracing enabled

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

Link: http://lkml.kernel.org/r/20200317213417.209675068@goodmis.org

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt (VMware) 2020-03-17 17:32:33 -04:00
parent c9b7a4a72f
commit 8a815e6b8b

View File

@ -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: