perf evsel: Fix attr.exclude_kernel setting for default cycles:p

To allow probing the max attr.precise_ip setting for non-root users
we unconditionally set attr.exclude_kernel, which makes the detection
work but should be done only for !root, fix it.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: 97365e81 ("perf evsel: Set attr.exclude_kernel when probing max attr.precise_ip")
Link: http://lkml.kernel.org/n/tip-bl6bbxzxloonzvm4nvt7oqgj@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/evsel.c

@@ -273,7 +273,7 @@ struct perf_evsel *perf_evsel__new_cycles(void)
 	struct perf_event_attr attr = {
 		.type	= PERF_TYPE_HARDWARE,
 		.config	= PERF_COUNT_HW_CPU_CYCLES,
-		.exclude_kernel	= 1,
+		.exclude_kernel	= geteuid() != 0,
 	};
 	struct perf_evsel *evsel;