Hi, all I have a simple question about filters in libtraceevent. It looks like libtraceevent parses and matches filters in user-space, but kernel already implements filtering in kernel-space which is better because it should prevent events from generating, if not matched. So why doesn't libtraceevent use kernel filters? I am trying to filter out non-error block_rq_complete events, clearly I don't want to see rasdaemon woken up every time for error==0 case, which is literally all the time. BTW, the user-space filters have slightly different syntax with kernel-space filters, at least the regex matching looks slightly different to me. Am I miss anything here? Thanks!
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