simpleperf: reduce Record construction overhead while recording.
Avoid binary allocation and memory copy in ReadRecordsFromBuffer(),
thus reduce Record construction overhead in
EventSelectionSet::ReadMmapEventDataForFd().
Remove RecordCache used while recording. Replace it with
RecordFileWriter::SortDataSection(). For unwinding while
recording, use low watermark to make records almost sorted
when dumped from the kernel.
Bug: 30649868
Test: run simpleperf_unit_test.
Change-Id: Ie5fb942046900a5960b3c990cf4177c026eaadfb
9 files changed