Re: [PATCH 1/5] perf core: Introduce new ioctl options to pause and resume ring buffer

[Wangnan (F)]

On 2016/3/23 17:16, Peter Zijlstra wrote:
> On Mon, Mar 14, 2016 at 09:59:41AM +0000, Wang Nan wrote:
> > Add new ioctl() to pause/resume ring-buffer output.
> >
> > In some situations we want to read from ring buffer only when we
> > ensure nothing can write to the ring buffer during reading. Without
> > this patch we have to turn off all events attached to this ring buffer
> > to achieve this.
> >
> > This patch is for supporting overwrite ring buffer. Following
> > commits will introduce new methods support reading from overwrite ring
> > buffer. Before reading caller must ensure the ring buffer is frozen, or
> > the reading is unreliable.
> > diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h
> > index 1afe962..a3c1903 100644
> > --- a/include/uapi/linux/perf_event.h
> > +++ b/include/uapi/linux/perf_event.h
> > @@ -401,6 +401,7 @@ struct perf_event_attr {
> >   #define PERF_EVENT_IOC_SET_FILTER	_IOW('$', 6, char *)
> >   #define PERF_EVENT_IOC_ID		_IOR('$', 7, __u64 *)
> >   #define PERF_EVENT_IOC_SET_BPF		_IOW('$', 8, __u32)
> > +#define PERF_EVENT_IOC_PAUSE_OUTPUT	_IOW('$', 9, __u32)

Glad to see you start to look at this patchset.



> Can you also do a patch to the man-pages?
>
>    http://man7.org/linux/man-pages/man2/perf_event_open.2.html

Sure.

I think I need to provide a patch for:

 http://git.kernel.org/cgit/docs/man-pages/man-pages.git

But which one should be the first? Shall we update man pages before
this patch be merged by upstream? Or Michael and Vince will consider
this problem?

Thank you.