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perf: Pass last sampling period to perf_sample_data_init()

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We always need to pass the last sample period to
perf_sample_data_init(), otherwise the event distribution will be
wrong. Thus, modifiyng the function interface with the required period
as argument. So basically a pattern like this:

        perf_sample_data_init(&data, ~0ULL);
        data.period = event->hw.last_period;

will now be like that:

        perf_sample_data_init(&data, ~0ULL, event->hw.last_period);

Avoids unininitialized data.period and simplifies code.

Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1333390758-10893-3-git-send-email-robert.richter@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Robert Richter
2012-04-02 20:19:08 +02:00
committed by Ingo Molnar
parent c75841a398
commit fd0d000b2c
15 changed files with 25 additions and 43 deletions
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4
arch/sparc/kernel/perf_event.c
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@@ -1296,8 +1296,6 @@ static int __kprobes perf_event_nmi_handler(struct notifier_block *self,
regs = args->regs;
perf_sample_data_init(&data, 0);
cpuc = &__get_cpu_var(cpu_hw_events);
/* If the PMU has the TOE IRQ enable bits, we need to do a
@@ -1321,7 +1319,7 @@ static int __kprobes perf_event_nmi_handler(struct notifier_block *self,
if (val & (1ULL << 31))
continue;
data.period = event->hw.last_period;
perf_sample_data_init(&data, 0, hwc->last_period);
if (!sparc_perf_event_set_period(event, hwc, idx))
continue;