On Thu, Jul 11, 2013 at 04:12:18PM +0300, Adrian Hunter wrote: > The event stream is not always parsable because the format of a sample > is dependent on the sample_type of the selected event. When there > is more than one selected event and the sample_types are not the > same then parsing becomes problematic. A sample can be matched to its > selected event using the ID that is allocated when the event is opened. > Unfortunately, to get the ID from the sample means first parsing it. > > This patch adds a new sample format bit PERF_SAMPLE_IDENTIFER that puts > the ID at a fixed position so that the ID can be retrieved without > parsing the sample. For sample events, that is the first position > immediately after the header. For non-sample events, that is the last > position.
There's events where this isn't a possible location; take PERF_RECORD_MMAP for instance; the tail is the complete filename. Why not always insert right after the header? Also; you forgot to update include/uapi/linux/perf_event.h:enum perf_event_type That's the format documentation. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
