tools/power/cpupower: allow running without cpu0

Linux-3.7 added CONFIG_BOOTPARAM_HOTPLUG_CPU0,
allowing systems to offline cpu0.

But when cpu0 is offline, cpupower monitor will not display all
processor and Mperf information:

[root@intel-skylake-dh-03 cpupower]# ./cpupower monitor
WARNING: at least one cpu is offline
    |Idle_Stats
CPU | POLL | C1-S | C1E- | C3-S | C6-S | C7s- | C8-S
   4|  0.00|  0.00|  0.00|  0.00|  0.90|  0.00| 96.13
   1|  0.00|  0.00|  5.49|  0.00|  0.01|  0.00| 92.26
   5|  0.00|  0.00|  0.00|  0.00|  0.46|  0.00| 99.50
   2| 45.42|  0.00|  0.00|  0.00| 22.94|  0.00| 28.84
   6|  0.00| 37.54|  0.00|  0.00|  0.00|  0.00|  0.00
   3|  0.00|  0.00|  0.00|  0.00|  0.30|  0.00| 91.99
   7|  0.00|  0.00|  0.00|  0.00|  4.70|  0.00|  0.70

This patch replaces the hard-coded use of cpu0 in cpupower with the
current cpu, allowing it to run without a cpu0.

After the patch is applied,

[root@intel-skylake-dh-03 cpupower]# ./cpupower monitor
WARNING: at least one cpu is offline
    |Nehalem                    || Mperf              || Idle_Stats
CPU | C3   | C6   | PC3  | PC6  || C0   | Cx   | Freq || POLL | C1-S | C1E- | C3-S | C6-S | C7s- | C8-S
   4|  0.01|  1.27|  0.00|  0.00||  0.04| 99.96|  3957||  0.00|  0.00|  0.00|  0.00|  1.43|  0.00| 98.52
   1|  0.00| 98.82|  0.00|  0.00||  0.05| 99.95|  3361||  0.00|  0.00|  0.01|  0.00|  0.03|  0.00| 99.88
   5|  0.00| 98.82|  0.00|  0.00||  0.09| 99.91|  3917||  0.00|  0.00|  0.00|  0.00| 99.38|  0.00|  0.50
   2|  0.33|  0.00|  0.00|  0.00||  0.00|100.00|  3890||  0.00|  0.00|  0.00|  0.00|  0.00|  0.00|100.00
   6|  0.33|  0.00|  0.00|  0.00||  0.01| 99.99|  3903||  0.00|  0.00|  0.00|  0.00|  0.00|  0.00| 99.99
   3|  0.01|  0.71|  0.00|  0.00||  0.06| 99.94|  3678||  0.00|  0.00|  0.00|  0.00|  0.80|  0.00| 99.13
   7|  0.01|  0.71|  0.00|  0.00||  0.03| 99.97|  3538||  0.00|  0.69| 11.70|  0.00|  0.00|  0.00| 87.57

There are some minor cleanups included in this patch.

Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Thomas Renninger <trenn@suse.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

4 files changed, 10 insertions, 9 deletions

diff --git a/tools/power/cpupower/utils/idle_monitor/hsw_ext_idle.c b/tools/power/cpupower/utils/idle_monitor/hsw_ext_idle.c
index ebeaba6571a3..f794d6bbb7e9 100644
--- a/tools/power/cpupower/utils/idle_monitor/hsw_ext_idle.c
+++ b/tools/power/cpupower/utils/idle_monitor/hsw_ext_idle.c
@@ -123,7 +123,7 @@ static int hsw_ext_start(void)
 			previous_count[num][cpu] = val;
 		}
 	}
-	hsw_ext_get_count(TSC, &tsc_at_measure_start, 0);
+	hsw_ext_get_count(TSC, &tsc_at_measure_start, base_cpu);
 	return 0;
 }
 
@@ -132,7 +132,7 @@ static int hsw_ext_stop(void)
 	unsigned long long val;
 	int num, cpu;
 
-	hsw_ext_get_count(TSC, &tsc_at_measure_end, 0);
+	hsw_ext_get_count(TSC, &tsc_at_measure_end, base_cpu);
 
 	for (num = 0; num < HSW_EXT_CSTATE_COUNT; num++) {
 		for (cpu = 0; cpu < cpu_count; cpu++) {
diff --git a/tools/power/cpupower/utils/idle_monitor/mperf_monitor.c b/tools/power/cpupower/utils/idle_monitor/mperf_monitor.c
index c83f1606970b..d7c2a6d13dea 100644
--- a/tools/power/cpupower/utils/idle_monitor/mperf_monitor.c
+++ b/tools/power/cpupower/utils/idle_monitor/mperf_monitor.c
@@ -80,7 +80,8 @@ static int *is_valid;
 static int mperf_get_tsc(unsigned long long *tsc)
 {
 	int ret;
-	ret = read_msr(0, MSR_TSC, tsc);
+
+	ret = read_msr(base_cpu, MSR_TSC, tsc);
 	if (ret)
 		dprint("Reading TSC MSR failed, returning %llu\n", *tsc);
 	return ret;
diff --git a/tools/power/cpupower/utils/idle_monitor/nhm_idle.c b/tools/power/cpupower/utils/idle_monitor/nhm_idle.c
index d2a91dd0d563..abf8cb5f7349 100644
--- a/tools/power/cpupower/utils/idle_monitor/nhm_idle.c
+++ b/tools/power/cpupower/utils/idle_monitor/nhm_idle.c
@@ -129,7 +129,7 @@ static int nhm_start(void)
 	int num, cpu;
 	unsigned long long dbg, val;
 
-	nhm_get_count(TSC, &tsc_at_measure_start, 0);
+	nhm_get_count(TSC, &tsc_at_measure_start, base_cpu);
 
 	for (num = 0; num < NHM_CSTATE_COUNT; num++) {
 		for (cpu = 0; cpu < cpu_count; cpu++) {
@@ -137,7 +137,7 @@ static int nhm_start(void)
 			previous_count[num][cpu] = val;
 		}
 	}
-	nhm_get_count(TSC, &dbg, 0);
+	nhm_get_count(TSC, &dbg, base_cpu);
 	dprint("TSC diff: %llu\n", dbg - tsc_at_measure_start);
 	return 0;
 }
@@ -148,7 +148,7 @@ static int nhm_stop(void)
 	unsigned long long dbg;
 	int num, cpu;
 
-	nhm_get_count(TSC, &tsc_at_measure_end, 0);
+	nhm_get_count(TSC, &tsc_at_measure_end, base_cpu);
 
 	for (num = 0; num < NHM_CSTATE_COUNT; num++) {
 		for (cpu = 0; cpu < cpu_count; cpu++) {
@@ -156,7 +156,7 @@ static int nhm_stop(void)
 			current_count[num][cpu] = val;
 		}
 	}
-	nhm_get_count(TSC, &dbg, 0);
+	nhm_get_count(TSC, &dbg, base_cpu);
 	dprint("TSC diff: %llu\n", dbg - tsc_at_measure_end);
 
 	return 0;
diff --git a/tools/power/cpupower/utils/idle_monitor/snb_idle.c b/tools/power/cpupower/utils/idle_monitor/snb_idle.c
index efc8a69c9aba..a2b45219648d 100644
--- a/tools/power/cpupower/utils/idle_monitor/snb_idle.c
+++ b/tools/power/cpupower/utils/idle_monitor/snb_idle.c
@@ -120,7 +120,7 @@ static int snb_start(void)
 			previous_count[num][cpu] = val;
 		}
 	}
-	snb_get_count(TSC, &tsc_at_measure_start, 0);
+	snb_get_count(TSC, &tsc_at_measure_start, base_cpu);
 	return 0;
 }
 
@@ -129,7 +129,7 @@ static int snb_stop(void)
 	unsigned long long val;
 	int num, cpu;
 
-	snb_get_count(TSC, &tsc_at_measure_end, 0);
+	snb_get_count(TSC, &tsc_at_measure_end, base_cpu);
 
 	for (num = 0; num < SNB_CSTATE_COUNT; num++) {
 		for (cpu = 0; cpu < cpu_count; cpu++) {