Hello. On 10/12/2015 12:02 PM, Kaixu Xia wrote:
In some scenarios we don't want to output trace data when sampling to reduce overhead. This patch adds the flag sample_disable to implement this function. By setting this flag and integrating with ebpf, we can control the data output process and get the samples we are most interested in. Signed-off-by: Kaixu Xia <xiaka...@huawei.com>
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diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c index 29ace10..4ae82c9 100644 --- a/kernel/bpf/arraymap.c +++ b/kernel/bpf/arraymap.c
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diff --git a/kernel/events/core.c b/kernel/events/core.c index b11756f..f6ef45c 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -6337,6 +6337,9 @@ static int __perf_event_overflow(struct perf_event *event, irq_work_queue(&event->pending); } + if ((event->sample_disable) && atomic_read(event->sample_disable))
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