Re: [PATCH 0/3] ftrace: updates for tip

From: Ingo Molnar
Date: Thu Dec 04 2008 - 03:20:28 EST

* Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:

> Ingo,
> This series has three patches.
> The first patch adds a new feature that I've been wanting to have for some
> time and Arjan even requested. That is to pick a function and only
> trace that function and its children. Dynamic ftrace and function
> graph needs to be enabled for this.
> To do the above, I added a "trace" flags field in the task structure.
> The second patch uses this for the ftrace pid code. It searches for
> the task based on the pid and sets the trace flag, then in the
> ftrace function caller it only needs to check this flag.
> This means we can now trace more than one pid without any more overhead.
> It also means that we should be able to use the name space code that
> the container guys want us to. But since I'm not very up on the
> namespace code, I'm still using just the normal 'pid'. I've Cc'd the
> container folks so perhaps they could write up a patch for me ;-)
> Note: When writing to the set_ftrace_pid two things happen.
> - The task with the matching pid gets the trace flag set.
> - Any other task has its trace flag cleared.
> #2 needs to be addressed when converting to pid name spaces.
> Just because it is not enough to simply find the matching task.
> It may be good enough to just clear all tasks and then find the
> one that matches.
> The last patch makes the function graph tracer honor the set_ftrace_pid.
> The following patches are in:
> git://
> branch: tip/devel
> Steven Rostedt (3):
> ftrace: graph of a single function
> ftrace: use task struct trace flag to filter on pid
> ftrace: trace single pid for function graph tracer
> ----
> include/linux/ftrace.h | 46 +++++++++
> include/linux/sched.h | 4 +
> kernel/trace/ftrace.c | 257 +++++++++++++++++++++++++++++++++++++++++++++++-
> kernel/trace/trace.c | 11 ++
> kernel/trace/trace.h | 40 +++++++-
> 5 files changed, 353 insertions(+), 5 deletions(-)
> --

pulled, thanks Steve!

These are some very nice changes!

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at