diff options
Diffstat (limited to 'tools/power/cpupower/utils/idle_monitor/mperf_monitor.c')
| -rw-r--r-- | tools/power/cpupower/utils/idle_monitor/mperf_monitor.c | 64 |
1 files changed, 53 insertions, 11 deletions
diff --git a/tools/power/cpupower/utils/idle_monitor/mperf_monitor.c b/tools/power/cpupower/utils/idle_monitor/mperf_monitor.c index 44806a6dae11..e7d48cb563c0 100644 --- a/tools/power/cpupower/utils/idle_monitor/mperf_monitor.c +++ b/tools/power/cpupower/utils/idle_monitor/mperf_monitor.c @@ -19,6 +19,10 @@ #define MSR_APERF 0xE8 #define MSR_MPERF 0xE7 +#define RDPRU ".byte 0x0f, 0x01, 0xfd" +#define RDPRU_ECX_MPERF 0 +#define RDPRU_ECX_APERF 1 + #define MSR_TSC 0x10 #define MSR_AMD_HWCR 0xc0010015 @@ -86,15 +90,51 @@ static int mperf_get_tsc(unsigned long long *tsc) return ret; } +static int get_aperf_mperf(int cpu, unsigned long long *aval, + unsigned long long *mval) +{ + unsigned long low_a, high_a; + unsigned long low_m, high_m; + int ret; + + /* + * Running on the cpu from which we read the registers will + * prevent APERF/MPERF from going out of sync because of IPI + * latency introduced by read_msr()s. + */ + if (mperf_monitor.flags.per_cpu_schedule) { + if (bind_cpu(cpu)) + return 1; + } + + if (cpupower_cpu_info.caps & CPUPOWER_CAP_AMD_RDPRU) { + asm volatile(RDPRU + : "=a" (low_a), "=d" (high_a) + : "c" (RDPRU_ECX_APERF)); + asm volatile(RDPRU + : "=a" (low_m), "=d" (high_m) + : "c" (RDPRU_ECX_MPERF)); + + *aval = ((low_a) | (high_a) << 32); + *mval = ((low_m) | (high_m) << 32); + + return 0; + } + + ret = read_msr(cpu, MSR_APERF, aval); + ret |= read_msr(cpu, MSR_MPERF, mval); + + return ret; +} + static int mperf_init_stats(unsigned int cpu) { - unsigned long long val; + unsigned long long aval, mval; int ret; - ret = read_msr(cpu, MSR_APERF, &val); - aperf_previous_count[cpu] = val; - ret |= read_msr(cpu, MSR_MPERF, &val); - mperf_previous_count[cpu] = val; + ret = get_aperf_mperf(cpu, &aval, &mval); + aperf_previous_count[cpu] = aval; + mperf_previous_count[cpu] = mval; is_valid[cpu] = !ret; return 0; @@ -102,13 +142,12 @@ static int mperf_init_stats(unsigned int cpu) static int mperf_measure_stats(unsigned int cpu) { - unsigned long long val; + unsigned long long aval, mval; int ret; - ret = read_msr(cpu, MSR_APERF, &val); - aperf_current_count[cpu] = val; - ret |= read_msr(cpu, MSR_MPERF, &val); - mperf_current_count[cpu] = val; + ret = get_aperf_mperf(cpu, &aval, &mval); + aperf_current_count[cpu] = aval; + mperf_current_count[cpu] = mval; is_valid[cpu] = !ret; return 0; @@ -305,6 +344,9 @@ struct cpuidle_monitor *mperf_register(void) if (init_maxfreq_mode()) return NULL; + if (cpupower_cpu_info.vendor == X86_VENDOR_AMD) + mperf_monitor.flags.per_cpu_schedule = 1; + /* Free this at program termination */ is_valid = calloc(cpu_count, sizeof(int)); mperf_previous_count = calloc(cpu_count, sizeof(unsigned long long)); @@ -333,7 +375,7 @@ struct cpuidle_monitor mperf_monitor = { .stop = mperf_stop, .do_register = mperf_register, .unregister = mperf_unregister, - .needs_root = 1, + .flags.needs_root = 1, .overflow_s = 922000000 /* 922337203 seconds TSC overflow at 20GHz */ }; |