[PATCH -next RFC -v2 11/11] cpuset: use partition_cpus_change for setting exclusive cpus

Chen Ridong posted 11 patches 3 weeks, 2 days ago
There is a newer version of this series
[PATCH -next RFC -v2 11/11] cpuset: use partition_cpus_change for setting exclusive cpus
Posted by Chen Ridong 3 weeks, 2 days ago
From: Chen Ridong <chenridong@huawei.com>

Previous patches have refactored partition_cpus_change. Now replace the
exclusive cpus setting logic with this helper function.

Signed-off-by: Chen Ridong <chenridong@huawei.com>
---
 kernel/cgroup/cpuset.c | 29 ++---------------------------
 1 file changed, 2 insertions(+), 27 deletions(-)

diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 785a2740b0ea..6a44dfabe9dd 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -2562,8 +2562,6 @@ static int update_exclusive_cpumask(struct cpuset *cs, struct cpuset *trialcs,
 {
 	int retval;
 	struct tmpmasks tmp;
-	struct cpuset *parent = parent_cs(cs);
-	bool invalidate = false;
 	bool force = false;
 	int old_prs = cs->partition_root_state;
 
@@ -2595,32 +2593,9 @@ static int update_exclusive_cpumask(struct cpuset *cs, struct cpuset *trialcs,
 	if (alloc_tmpmasks(&tmp))
 		return -ENOMEM;
 
-	if (old_prs) {
-		if (cpumask_empty(trialcs->effective_xcpus)) {
-			invalidate = true;
-			cs->prs_err = PERR_INVCPUS;
-		} else if (prstate_housekeeping_conflict(old_prs, trialcs->effective_xcpus)) {
-			invalidate = true;
-			cs->prs_err = PERR_HKEEPING;
-		} else if (tasks_nocpu_error(parent, cs, trialcs->effective_xcpus)) {
-			invalidate = true;
-			cs->prs_err = PERR_NOCPUS;
-		}
+	trialcs->prs_err = PERR_NONE;
+	partition_cpus_change(cs, trialcs, &tmp);
 
-		if (is_remote_partition(cs)) {
-			if (invalidate)
-				remote_partition_disable(cs, &tmp);
-			else
-				remote_cpus_update(cs, trialcs->exclusive_cpus,
-						   trialcs->effective_xcpus, &tmp);
-		} else if (invalidate) {
-			update_parent_effective_cpumask(cs, partcmd_invalidate,
-							NULL, &tmp);
-		} else {
-			update_parent_effective_cpumask(cs, partcmd_update,
-						trialcs->effective_xcpus, &tmp);
-		}
-	}
 	spin_lock_irq(&callback_lock);
 	cpumask_copy(cs->exclusive_cpus, trialcs->exclusive_cpus);
 	cpumask_copy(cs->effective_xcpus, trialcs->effective_xcpus);
-- 
2.34.1
Re: [PATCH -next RFC -v2 11/11] cpuset: use partition_cpus_change for setting exclusive cpus
Posted by Waiman Long 2 weeks, 3 days ago
On 9/8/25 11:32 PM, Chen Ridong wrote:
> From: Chen Ridong <chenridong@huawei.com>
>
> Previous patches have refactored partition_cpus_change. Now replace the
> exclusive cpus setting logic with this helper function.
Nit: The term "refactor" usually mean updating the code of an existing 
function, sometimes extracting out code into new helper functions. In 
your case, partition_cpus_change() is a new helper function. This is 
also an issue in some of the earlier patches. I would prefer using 
phrase like "A previous patch has introduced a new helper function 
partition_cpus_change()"
>
> Signed-off-by: Chen Ridong <chenridong@huawei.com>
> ---
>   kernel/cgroup/cpuset.c | 29 ++---------------------------
>   1 file changed, 2 insertions(+), 27 deletions(-)
>
> diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
> index 785a2740b0ea..6a44dfabe9dd 100644
> --- a/kernel/cgroup/cpuset.c
> +++ b/kernel/cgroup/cpuset.c
> @@ -2562,8 +2562,6 @@ static int update_exclusive_cpumask(struct cpuset *cs, struct cpuset *trialcs,
>   {
>   	int retval;
>   	struct tmpmasks tmp;
> -	struct cpuset *parent = parent_cs(cs);
> -	bool invalidate = false;
>   	bool force = false;
>   	int old_prs = cs->partition_root_state;
>   
> @@ -2595,32 +2593,9 @@ static int update_exclusive_cpumask(struct cpuset *cs, struct cpuset *trialcs,
>   	if (alloc_tmpmasks(&tmp))
>   		return -ENOMEM;
>   
> -	if (old_prs) {
> -		if (cpumask_empty(trialcs->effective_xcpus)) {
> -			invalidate = true;
> -			cs->prs_err = PERR_INVCPUS;
> -		} else if (prstate_housekeeping_conflict(old_prs, trialcs->effective_xcpus)) {
> -			invalidate = true;
> -			cs->prs_err = PERR_HKEEPING;
> -		} else if (tasks_nocpu_error(parent, cs, trialcs->effective_xcpus)) {
> -			invalidate = true;
> -			cs->prs_err = PERR_NOCPUS;
> -		}
> +	trialcs->prs_err = PERR_NONE;
> +	partition_cpus_change(cs, trialcs, &tmp);
>   
> -		if (is_remote_partition(cs)) {
> -			if (invalidate)
> -				remote_partition_disable(cs, &tmp);
> -			else
> -				remote_cpus_update(cs, trialcs->exclusive_cpus,
> -						   trialcs->effective_xcpus, &tmp);
> -		} else if (invalidate) {
> -			update_parent_effective_cpumask(cs, partcmd_invalidate,
> -							NULL, &tmp);
> -		} else {
> -			update_parent_effective_cpumask(cs, partcmd_update,
> -						trialcs->effective_xcpus, &tmp);
> -		}
> -	}
>   	spin_lock_irq(&callback_lock);
>   	cpumask_copy(cs->exclusive_cpus, trialcs->exclusive_cpus);
>   	cpumask_copy(cs->effective_xcpus, trialcs->effective_xcpus);
Reviewed-by: Waiman Long <longman@redhat.com>
Re: [PATCH -next RFC -v2 11/11] cpuset: use partition_cpus_change for setting exclusive cpus
Posted by Chen Ridong 2 weeks, 2 days ago

On 2025/9/16 4:05, Waiman Long wrote:
> On 9/8/25 11:32 PM, Chen Ridong wrote:
>> From: Chen Ridong <chenridong@huawei.com>
>>
>> Previous patches have refactored partition_cpus_change. Now replace the
>> exclusive cpus setting logic with this helper function.
> Nit: The term "refactor" usually mean updating the code of an existing function, sometimes
> extracting out code into new helper functions. In your case, partition_cpus_change() is a new helper
> function. This is also an issue in some of the earlier patches. I would prefer using phrase like "A
> previous patch has introduced a new helper function partition_cpus_change()"

Thank you, will update.

>>
>> Signed-off-by: Chen Ridong <chenridong@huawei.com>
>> ---
>>   kernel/cgroup/cpuset.c | 29 ++---------------------------
>>   1 file changed, 2 insertions(+), 27 deletions(-)
>>
>> diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
>> index 785a2740b0ea..6a44dfabe9dd 100644
>> --- a/kernel/cgroup/cpuset.c
>> +++ b/kernel/cgroup/cpuset.c
>> @@ -2562,8 +2562,6 @@ static int update_exclusive_cpumask(struct cpuset *cs, struct cpuset *trialcs,
>>   {
>>       int retval;
>>       struct tmpmasks tmp;
>> -    struct cpuset *parent = parent_cs(cs);
>> -    bool invalidate = false;
>>       bool force = false;
>>       int old_prs = cs->partition_root_state;
>>   @@ -2595,32 +2593,9 @@ static int update_exclusive_cpumask(struct cpuset *cs, struct cpuset
>> *trialcs,
>>       if (alloc_tmpmasks(&tmp))
>>           return -ENOMEM;
>>   -    if (old_prs) {
>> -        if (cpumask_empty(trialcs->effective_xcpus)) {
>> -            invalidate = true;
>> -            cs->prs_err = PERR_INVCPUS;
>> -        } else if (prstate_housekeeping_conflict(old_prs, trialcs->effective_xcpus)) {
>> -            invalidate = true;
>> -            cs->prs_err = PERR_HKEEPING;
>> -        } else if (tasks_nocpu_error(parent, cs, trialcs->effective_xcpus)) {
>> -            invalidate = true;
>> -            cs->prs_err = PERR_NOCPUS;
>> -        }
>> +    trialcs->prs_err = PERR_NONE;
>> +    partition_cpus_change(cs, trialcs, &tmp);
>>   -        if (is_remote_partition(cs)) {
>> -            if (invalidate)
>> -                remote_partition_disable(cs, &tmp);
>> -            else
>> -                remote_cpus_update(cs, trialcs->exclusive_cpus,
>> -                           trialcs->effective_xcpus, &tmp);
>> -        } else if (invalidate) {
>> -            update_parent_effective_cpumask(cs, partcmd_invalidate,
>> -                            NULL, &tmp);
>> -        } else {
>> -            update_parent_effective_cpumask(cs, partcmd_update,
>> -                        trialcs->effective_xcpus, &tmp);
>> -        }
>> -    }
>>       spin_lock_irq(&callback_lock);
>>       cpumask_copy(cs->exclusive_cpus, trialcs->exclusive_cpus);
>>       cpumask_copy(cs->effective_xcpus, trialcs->effective_xcpus);
> Reviewed-by: Waiman Long <longman@redhat.com>

-- 
Best regards,
Ridong