Messages in this thread | | | Date | Mon, 14 Jul 2008 21:43:46 -0400 (EDT) | From | Steven Rostedt <> | Subject | Re: [PATCH -v2] ftrace: Documentation |
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On Mon, 14 Jul 2008, Eric W. Biederman wrote:
> > Steven Rostedt <rostedt@goodmis.org> writes: > > > Actually it is a /debug (or /sys/mount/debug if you prefer) file. > > Got it. I haven't ever actually seen anyone use debugfs. > > > I'd be interested in knowing who would want namespaces in traces. I've > > basically only used tracing to see "what's happening in the kernel here?". > > Where I only use the pid to differentiate between the tasks I know are > > running. > > > Hence, tracing is much like printk. Does it really matter with these > > outputs. But ftrace is pluggable, pid namespaces may matter in future > > plugins.
Bare with me, I'm new to the namespace concept of pids.
> > So it would not be hard to capture the pid namespace in mount or > even look at current to get it (although the last is a little odd).
From userspace or from with the kernel (doing the trace)
> > I'm not at all certain if it makes sense. If this is something > an ordinary user could use then we definitely want to do something. > > Is tracing possible without inserting kernel modules?
The tracer is built into the kernel (no module needed).
-- Steve
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