Messages in this thread Patch in this message | | | From | Mischa Jonker <> | Subject | [PATCH] ARC: perf: ARC 700 PMU doesn't support sampling events | Date | Wed, 13 Nov 2013 16:06:06 +0100 |
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The ARC 700 does not have an interrupt associated with it, and as such it cannot trigger when a counter overflows. As the counters are 48 bit, it will usually take at least 100 days before a counter overflows, so for mere counting of events, there is no problem. Sampling is not supported though.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Mischa Jonker <mjonker@synopsys.com> --- arch/arc/kernel/perf_event.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/arch/arc/kernel/perf_event.c b/arch/arc/kernel/perf_event.c index 759e5f3..e46d81f 100644 --- a/arch/arc/kernel/perf_event.c +++ b/arch/arc/kernel/perf_event.c @@ -99,6 +99,10 @@ static int arc_pmu_event_init(struct perf_event *event) struct hw_perf_event *hwc = &event->hw; int ret; + /* ARC 700 PMU does not support sampling events */ + if (is_sampling_event(event)) + return -ENOENT; + switch (event->attr.type) { case PERF_TYPE_HARDWARE: if (event->attr.config >= PERF_COUNT_HW_MAX) -- 1.7.9.5
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