[PATCH] cpupower : Fix cpupower working when cpu0 is offline

[Abhishek Goel]

cpuidle_monitor used to assume that cpu0 is always online. Now the
cpuidle_monitor function searches for the first online cpu and use
it, instead of always using cpu0 which may not be online.

Signed-off-by: Abhishek Goel <hunt...@linux.vnet.ibm.com>
---
 tools/power/cpupower/utils/idle_monitor/cpuidle_sysfs.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/tools/power/cpupower/utils/idle_monitor/cpuidle_sysfs.c 
b/tools/power/cpupower/utils/idle_monitor/cpuidle_sysfs.c
index 1b5da00..adacf99 100644
--- a/tools/power/cpupower/utils/idle_monitor/cpuidle_sysfs.c
+++ b/tools/power/cpupower/utils/idle_monitor/cpuidle_sysfs.c
@@ -130,15 +130,23 @@ static struct cpuidle_monitor *cpuidle_register(void)
 {
        int num;
        char *tmp;
+       int first_online_cpu;
+
+       for (num = 0; num < cpu_count; num++) {
+               if (cpupower_is_cpu_online(num))
+                       break;
+       };
+       first_online_cpu = num;
 
        /* Assume idle state count is the same for all CPUs */
-       cpuidle_sysfs_monitor.hw_states_num = cpuidle_state_count(0);
+       cpuidle_sysfs_monitor.hw_states_num =
+               cpuidle_state_count(first_online_cpu);
 
        if (cpuidle_sysfs_monitor.hw_states_num <= 0)
                return NULL;
 
        for (num = 0; num < cpuidle_sysfs_monitor.hw_states_num; num++) {
-               tmp = cpuidle_state_name(0, num);
+               tmp = cpuidle_state_name(first_online_cpu, num);
                if (tmp == NULL)
                        continue;
 
@@ -146,7 +154,7 @@ static struct cpuidle_monitor *cpuidle_register(void)
                strncpy(cpuidle_cstates[num].name, tmp, CSTATE_NAME_LEN - 1);
                free(tmp);
 
-               tmp = cpuidle_state_desc(0, num);
+               tmp = cpuidle_state_desc(first_online_cpu, num);
                if (tmp == NULL)
                        continue;
                strncpy(cpuidle_cstates[num].desc, tmp, CSTATE_DESC_LEN - 1);
-- 
2.9.3