diff options
| -rw-r--r-- | tools/power/x86/turbostat/turbostat.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c index adcf5f0a0633..6b72b922e2f5 100644 --- a/tools/power/x86/turbostat/turbostat.c +++ b/tools/power/x86/turbostat/turbostat.c @@ -2113,13 +2113,17 @@ int get_msr(int cpu, off_t offset, unsigned long long *msr) int probe_msr(int cpu, off_t offset) { ssize_t retval; - unsigned long long dummy; + unsigned long long value; assert(!no_msr); - retval = pread(get_msr_fd(cpu), &dummy, sizeof(dummy), offset); + retval = pread(get_msr_fd(cpu), &value, sizeof(value), offset); - if (retval != sizeof(dummy)) + /* + * Expect MSRs to accumulate some non-zero value since the system was powered on. + * Treat zero as a read failure. + */ + if (retval != sizeof(value) || value == 0) return 1; return 0; |