Merge tag 'perf-core-for-mingo-4.18-20180516' of git://git.kernel.org/pub/scm/linux...

Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:

- Add '-e intel_pt//u' test to the 'parse-events' 'perf test' entry,
  to help avoiding regressions in the events parser such as one
  that caused a revert in v4.17-rc (Arnaldo Carvalho de Melo)

- Fix NULL return handling in bpf__prepare_load() (YueHaibing)

- Warn about 'perf buildid-cache --purge-all' failures (Ravi Bangoria)

- Add infrastructure to help in writing eBPF C programs to be used
  with '-e name.c' type events in tools such as 'record' and 'trace',
  with headers for common constructs and an examples directory that
  will get populated as we add more such helpers and the 'perf bpf'
  branch that Jiri Olsa has been working on (Arnaldo Carvalho de Melo)

- Handle uncore event aliases in small groups properly (Kan Liang)

- Use the "_stest" symbol to identify the kernel map when loading kcore (Adrian Hunter)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>