Re: [PATCH v2] cpupower : Fix cpupower working when cpu0 is offline

[Shuah Khan]

On 11/07/2017 01:58 AM, Abhishek wrote:
> Hi,
> 
> Can you have a look at it?
> 
> Thanks and Regards,
> 
> Abhishek Goel
> 
> System Engineer
> 
> IBM India Pvt. Ltd.
> 

Please refrain from top posting on kernel email thread.
In-lining comments and bottom posting is the norm.

> 
> On 11/07/2017 12:50 PM, Abhishek Goel wrote:
>> cpuidle_monitor used to assume that cpu0 is always online which is not
>> a valid assumption on POWER machines. This patch fixes this by searching
>> for the first online cpu and uses it, instead of always using cpu0 for
>> monitoring which may not be online.
>>
>> Signed-off-by: Abhishek Goel 
>> ---
>> v2: Commit message updated.
>> ---
>>   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;

Isn't it simpler to use sched_getcpu()n instead and use that instead
of walking the sysfs nodes since assumption is made that the idle state
count is the same for all CPUs

>>
>>   /* Assume idle state count is the same for all CPUs */
>> -    cpuidle_sysfs_monitor.hw_states_num = cpuidle_state_count(0);

This simply be:

cpuidle_sysfs_monitor.hw_states_num = cpuidle_state_count(sched_getcpu);

>> +    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);
> 

thanks,
-- Shuah

Re: [PATCH v2] cpupower : Fix cpupower working when cpu0 is offline

[Shuah Khan]

On 11/07/2017 01:58 AM, Abhishek wrote:
> Hi,
> 
> Can you have a look at it?
> 
> Thanks and Regards,
> 
> Abhishek Goel
> 
> System Engineer
> 
> IBM India Pvt. Ltd.
> 

Please refrain from top posting on kernel email thread.
In-lining comments and bottom posting is the norm.

> 
> On 11/07/2017 12:50 PM, Abhishek Goel wrote:
>> cpuidle_monitor used to assume that cpu0 is always online which is not
>> a valid assumption on POWER machines. This patch fixes this by searching
>> for the first online cpu and uses it, instead of always using cpu0 for
>> monitoring which may not be online.
>>
>> Signed-off-by: Abhishek Goel 
>> ---
>> v2: Commit message updated.
>> ---
>>   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;

Isn't it simpler to use sched_getcpu()n instead and use that instead
of walking the sysfs nodes since assumption is made that the idle state
count is the same for all CPUs

>>
>>   /* Assume idle state count is the same for all CPUs */
>> -    cpuidle_sysfs_monitor.hw_states_num = cpuidle_state_count(0);

This simply be:

cpuidle_sysfs_monitor.hw_states_num = cpuidle_state_count(sched_getcpu);

>> +    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);
> 

thanks,
-- Shuah

Re: [PATCH v2] cpupower : Fix cpupower working when cpu0 is offline

[Abhishek]

Hi,

Can you have a look at it?

Thanks and Regards,

Abhishek Goel

System Engineer

IBM India Pvt. Ltd.


On 11/07/2017 12:50 PM, Abhishek Goel wrote:

cpuidle_monitor used to assume that cpu0 is always online which is not
a valid assumption on POWER machines. This patch fixes this by searching
for the first online cpu and uses it, instead of always using cpu0 for
monitoring which may not be online.

Signed-off-by: Abhishek Goel 
---
v2: Commit message updated.
---
  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);

Re: [PATCH v2] cpupower : Fix cpupower working when cpu0 is offline

[Abhishek]

Hi,

Can you have a look at it?

Thanks and Regards,

Abhishek Goel

System Engineer

IBM India Pvt. Ltd.


On 11/07/2017 12:50 PM, Abhishek Goel wrote:

cpuidle_monitor used to assume that cpu0 is always online which is not
a valid assumption on POWER machines. This patch fixes this by searching
for the first online cpu and uses it, instead of always using cpu0 for
monitoring which may not be online.

Signed-off-by: Abhishek Goel 
---
v2: Commit message updated.
---
  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);

[PATCH v2] cpupower : Fix cpupower working when cpu0 is offline

[Abhishek Goel]

cpuidle_monitor used to assume that cpu0 is always online which is not
a valid assumption on POWER machines. This patch fixes this by searching
for the first online cpu and uses it, instead of always using cpu0 for
monitoring which may not be online.

Signed-off-by: Abhishek Goel 
---
v2: Commit message updated.
---
 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

[PATCH v2] cpupower : Fix cpupower working when cpu0 is offline

[Abhishek Goel]

cpuidle_monitor used to assume that cpu0 is always online which is not
a valid assumption on POWER machines. This patch fixes this by searching
for the first online cpu and uses it, instead of always using cpu0 for
monitoring which may not be online.

Signed-off-by: Abhishek Goel 
---
v2: Commit message updated.
---
 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