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Subject: Re: [RFC] perf: need to expose sched_clock to correlate user
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From: Pawel Moll <pawel.moll@arm.com>
To: John Stultz <john.stultz@linaro.org>
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On Wed, 2013-04-03 at 18:50 +0100, John Stultz wrote:
> I get the reasoning around reusing the fd we already have, but is the 
> possibility of a dynamic chardev pathname really a big concern?

Well, in my particular development system I have no udev, so I had to
manually do "mknod". Perf syscall works out of the box. Of course one
could say it's my problem...

> I'm guessing the private_data on the perf file is already used?

Of course.

> Maybe can we extend the dynamic posix clock code to work on more then 
> just the chardev? 

The idea I'm following now is to make the dynamic clock framework even
more generic, so there could be a clock associated with an arbitrary
struct file * (the perf syscall is getting one with
anon_inode_getfile()). I don't know how to get this done yet, but I'll
give it a try and report.

Paweł