Messages in this thread | | | Subject | Re: Ftrace: can trace kthread? | From | "Figo.zhang" <> | Date | Thu, 21 Oct 2010 16:59:02 +0800 |
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> I just > echo 0 > tracing_enabled > echo function > current_tracer > echo 374(pid of flush) > set_ftrace_pid > echo 1 > tracing_enabled > wait some time > echo 0 > tracing_enabled > cat trace > > So I think this answer your question "could kthread be traced?"
i do it the same of you.
[root@myhost tracing]# ps -ax | grep flush Warning: bad ps syntax, perhaps a bogus '-'? See http://procps.sf.net/faq.html 1205 ? S 0:01 [flush-8:0] 11852 pts/1 S+ 0:00 grep flush [root@myhost tracing]#
so my flusher pid is 1205, i do it as below:
[root@myhost tracing]# echo 0 > tracing_enabled [root@myhost tracing]# echo function > current_tracer [root@myhost tracing]# echo 1205 > set_ftrace_pid [root@myhost tracing]# echo 1 > tracing_enabled
wait ... and open some pdf files, let system eat huge memory...
[root@myhost tracing]# echo 0 > tracing_enabled [root@myhost tracing]# cat trace # tracer: function # # TASK-PID CPU# TIMESTAMP FUNCTION # | | | | |
but i canot trace nothing.
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