Messages in this thread | | | Date | Sat, 23 Feb 2008 11:01:58 -0800 | From | Andrew Morton <> | Subject | Re: [PATCH] x86: add the debugfs interface for the sysprof tool |
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On Sat, 23 Feb 2008 16:54:49 +0200 "Pekka Enberg" <penberg@cs.helsinki.fi> wrote:
> On Sat, Feb 23, 2008 at 10:11 AM, Andrew Morton > <akpm@linux-foundation.org> wrote: > > Seems a poor idea to me. Sure, oprofile is "hard to set up", but not if > > your distributor already did it for you. > > > > Sidebar: the code uses the utterly crappy register_timer_hook() which > > > > a) is woefully misnamed and > > > > b) is racy and > > > > c) will disrupt oprofile if it is being used. And vice versa. > > I wonder if sysprof should hook to the same interrupt as oprofile then?
oprofile uses register_timer_hook() for its oh-crap-nothing-else-works fallback iirc. It's a useful fallback: I used it a few centuries ago on some el-cheapo VIA CPU-based thing we had at Digeo.
It's unclear to me whether all this stuff works with NO_HZ=y, btw. Didn't we just lose the regular timer interrupts which these clients depend upon?
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