From 6d6501d912a9a5e1b73d7fbf419b90a8ec11ed7a Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Thu, 15 Oct 2020 14:50:16 +0200 Subject: [PATCH] tools/power/turbostat: Read energy_perf_bias from sysfs ... instead of poking at the MSR directly. Signed-off-by: Borislav Petkov Cc: Len Brown Cc: linux-pm@vger.kernel.org Link: https://lkml.kernel.org/r/20201029190259.3476-3-bp@alien8.de --- tools/power/x86/turbostat/turbostat.c | 29 ++++++++++++++++++++++----- 1 file changed, 24 insertions(+), 5 deletions(-) diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c index 33b370865d16..0baec7ea1bbd 100644 --- a/tools/power/x86/turbostat/turbostat.c +++ b/tools/power/x86/turbostat/turbostat.c @@ -1721,6 +1721,25 @@ int get_mp(int cpu, struct msr_counter *mp, unsigned long long *counterp) return 0; } +int get_epb(int cpu) +{ + char path[128 + PATH_BYTES]; + int ret, epb = -1; + FILE *fp; + + sprintf(path, "/sys/devices/system/cpu/cpu%d/power/energy_perf_bias", cpu); + + fp = fopen_or_die(path, "r"); + + ret = fscanf(fp, "%d", &epb); + if (ret != 1) + err(1, "%s(%s)", __func__, path); + + fclose(fp); + + return epb; +} + void get_apic_id(struct thread_data *t) { unsigned int eax, ebx, ecx, edx; @@ -3631,9 +3650,8 @@ dump_sysfs_pstate_config(void) */ int print_epb(struct thread_data *t, struct core_data *c, struct pkg_data *p) { - unsigned long long msr; char *epb_string; - int cpu; + int cpu, epb; if (!has_epb) return 0; @@ -3649,10 +3667,11 @@ int print_epb(struct thread_data *t, struct core_data *c, struct pkg_data *p) return -1; } - if (get_msr(cpu, MSR_IA32_ENERGY_PERF_BIAS, &msr)) + epb = get_epb(cpu); + if (epb < 0) return 0; - switch (msr & 0xF) { + switch (epb) { case ENERGY_PERF_BIAS_PERFORMANCE: epb_string = "performance"; break; @@ -3666,7 +3685,7 @@ int print_epb(struct thread_data *t, struct core_data *c, struct pkg_data *p) epb_string = "custom"; break; } - fprintf(outf, "cpu%d: MSR_IA32_ENERGY_PERF_BIAS: 0x%08llx (%s)\n", cpu, msr, epb_string); + fprintf(outf, "cpu%d: EPB: %d (%s)\n", cpu, epb, epb_string); return 0; }