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perf, x86, Pentium4: Clear the P4_CCCR_FORCE_OVF flag
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If on Pentium4 CPUs the FORCE_OVF flag is set then an NMI happens
on every event, which can generate a flood of NMIs. Clear it.

Reported-by: Vince Weaver <vweaver1@eecs.utk.edu>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Lin Ming authored and Ingo Molnar committed Aug 25, 2010
1 parent 151772d commit 8d33091
Showing 1 changed file with 2 additions and 0 deletions.
2 changes: 2 additions & 0 deletions arch/x86/kernel/cpu/perf_event_p4.c
Original file line number Diff line number Diff line change
Expand Up @@ -497,6 +497,8 @@ static int p4_hw_config(struct perf_event *event)
event->hw.config |= event->attr.config &
(p4_config_pack_escr(P4_ESCR_MASK_HT) |
p4_config_pack_cccr(P4_CCCR_MASK_HT | P4_CCCR_RESERVED));

event->hw.config &= ~P4_CCCR_FORCE_OVF;
}

rc = x86_setup_perfctr(event);
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