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Date: Tue, 22 Jun 2004 18:20:25 +0100
From: Christoph Hellwig <hch@infradead.org>
To: Mikael Pettersson <mikpe@csd.uu.se>
Cc: Andrew Morton <akpm@osdl.org>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH][1/6] perfctr-2.7.3 for 2.6.7-rc1-mm1: core
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On Tue, Jun 22, 2004 at 04:38:06PM +0200, Mikael Pettersson wrote:
> Swiching to open() on /proc/<pid>/<tid>/perfctr followed by ioctl()s
> would be easy to implement. But people @ LKML are sometimes violently
> opposed to ioctl()s, that's why the switch to syscalls happended.

I don't remember the details anymore, but lots of the syscalls could
really be read/write on special files.  I'll look through the code again
and send out draft API document.

> One concern is that there doesn't appear to be a user-visible shortcut
> to "your own" /proc/<pid>/<tid>/ like there was when /proc/self still
> had some useful meaning. This is merely annoying, not a show-stopper.

Shouldn't be a real problem to add one.