4.9-stable review patch. If anyone has any objections, please let me know.
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From: Abhishek Goel huntbag@linux.vnet.ibm.com
[ Upstream commit dbdc468f35ee827cab2753caa1c660bdb832243a ]
cpuidle_monitor used to assume that cpu0 is always online which is not a valid assumption on POWER machines. This patch fixes this by getting the cpu on which the current thread is running, instead of always using cpu0 for monitoring which may not be online.
Signed-off-by: Abhishek Goel huntbag@linux.vnet.ibm.com Signed-off-by: Shuah Khan shuahkh@osg.samsung.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- tools/power/cpupower/utils/idle_monitor/cpuidle_sysfs.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-)
--- a/tools/power/cpupower/utils/idle_monitor/cpuidle_sysfs.c +++ b/tools/power/cpupower/utils/idle_monitor/cpuidle_sysfs.c @@ -130,15 +130,18 @@ static struct cpuidle_monitor *cpuidle_r { int num; char *tmp; + int this_cpu; + + this_cpu = sched_getcpu();
/* 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(this_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(this_cpu, num); if (tmp == NULL) continue;
@@ -146,7 +149,7 @@ static struct cpuidle_monitor *cpuidle_r strncpy(cpuidle_cstates[num].name, tmp, CSTATE_NAME_LEN - 1); free(tmp);
- tmp = cpuidle_state_desc(0, num); + tmp = cpuidle_state_desc(this_cpu, num); if (tmp == NULL) continue; strncpy(cpuidle_cstates[num].desc, tmp, CSTATE_DESC_LEN - 1);