selftests/powerpc/pmu: Use signed long to read perf_event_paranoid
Excerpt from man 2 perf_event_open: /proc/sys/kernel/perf_event_paranoid The perf_event_paranoid file can be set to restrict access to the performance counters. 2 allow only user-space measurements. 1 allow both kernel and user measurements (default). 0 allow access to CPU-specific data but not raw tracepoint samples. -1 no restrictions. require_paranoia_below() should return 0 if perf_event_paranoid is below a specified level, the value from perf_event_paranoid is read into an unsigned long so the incorrect value is returned when perf_event_paranoid is set to -1. Without this patch applied there is the same number of selftests/powerpc which skip when /proc/sys/kernel/perf_event_paranoid is set to 1 or -1 but no skips when set to zero. With this patch applied there are no skipped selftests/powerpc test when /proc/sys/kernel/perf_event_paranoid is set to 0 or -1. Signed-off-by:Cyril Bur <cyrilbur@gmail.com> Signed-off-by:
Michael Ellerman <mpe@ellerman.id.au>
parent
f1fb60bf
Please register or sign in to comment