From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jes Sorensen <jes@sgi.com>
Date: Thu, 29 Jun 2006 09:37:40 +0000
Subject: Re: [PATCH] ia64: change usermode HZ to 250
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To: "Luck, Tony" <tony.luck@intel.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>, John Daiker <jdaiker@osdl.org>, John Hawkes <hawkes@sgi.com>, Arjan van de Ven <arjan@infradead.org>, Tony Luck <tony.luck@gmail.com>, Andrew Morton <akpm@osdl.org>, linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org, Jack Steiner <steiner@sgi.com>, Dan Higgins <djh@sgi.com>, Jeremy Higdon <jeremy@sgi.com>

>>>>> "Tony" = Luck, Tony <tony.luck@intel.com> writes:

Tony> Removing it completely might be better, it may force people to
Tony> look at how they are using HZ.  But there are probably many old
Tony> programs that have:

After reading through the discussion that was what I kept coming back
to.

Tony> #ifndef HZ #define HZ 60 #endif

Tony> So this won't catch them.

Tony> The ultimate safe solution might be:

Tony> #define HZ Fix your program to use sysconf(_SC_CLK_TCK)! \ (and
Tony> BTW, you should not include kernel headers)

Tony> Which is highly likely to cause a compile failure (but should at
Tony> least provide a clue to the user on what they should do).

You have my vote for that one. Anything else is just going to cause
those broken userapps to continue doing the wrong thing. We should
really do this on all archs though.

Cheers,
Jes