Re: [PATCH RFC] x86: avoid atomic operation in test_and_set_bit_lock if possible

Eric Dumazet
2011-03-24T21:02:47Z

Le jeudi 24 mars 2011 à 21:54 +0100, Ingo Molnar a écrit :

> Does it work better if you run it as root?
>

I confess I always am root on my dev machines :(

> To easiest way to debug as user is to do:
>
> echo -1 > /proc/sys/kernel/perf_event_paranoid
>
> and to put this into /etc/sysctl.conf:
>
> kernel.perf_event_paranoid = -1
>

Hmm... on one machine (HP BL460c G1 ) I do have :

[ 0.015998] Performance Events: PEBS fmt0+, Core2 events, Broken BIOS detected, using software events only.
[ 0.015998] [Firmware Bug]: the BIOS has corrupted hw-PMU resources (MSR 186 is 43003c)

and the other one (HB BL460c G6)

[ 0.122760] Performance Events: PEBS fmt1+, Nehalem events, Broken BIOS detected, using software events only.
[ 0.123047] [Firmware Bug]: the BIOS has corrupted hw-PMU resources (MSR 38d is 330)

Hmm.. I have latest HP BIOS.

Version: I15
Release Date: 10/25/2010

and

Version: I24
Release Date: 09/02/2010

I am pretty sure I used "-e ..." some time ago with same BIOS.