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Subject: CLOCK_REALTIME_RES and nanosecond resolution
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Linux Kernel list <linux-kernel@vger.kernel.org>
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Date: Tue, 08 Nov 2005 13:55:11 +1100
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Hi !

I noticed that we set

#define CLOCK_REALTIME_RES TICK_NSEC  /* In nano seconds. */

Unconditionally in kernel/posix-timer.c

Doesn't that mean that we'll advertise to userland (via clock_getres) a
resolution that is basically HZ ? We do get at lenght to get more
precise (up to ns) resolution in practice on many architectures but we
don't expose that to userland at all. Is this normal ?

Ben.