[PATCH -next 1/3] cgroup/cpuset: Correct invalid remote parition prs

Chen Ridong posted 3 patches 1 year, 5 months ago
There is a newer version of this series
[PATCH -next 1/3] cgroup/cpuset: Correct invalid remote parition prs
Posted by Chen Ridong 1 year, 5 months ago
When enable a remote partition, I found that:

cd /sys/fs/cgroup/
mkdir test
mkdir test/test1
echo +cpuset > cgroup.subtree_control
echo +cpuset >  test/cgroup.subtree_control
echo 3 > test/test1/cpuset.cpus
echo root > test/test1/cpuset.cpus.partition
cat test/test1/cpuset.cpus.partition
root invalid (Parent is not a partition root)

The parent of a remote partition could not be a root. This is due to the
emtpy effective_xcpus. It would be better to prompt the message "invalid
cpu list in cpuset.cpus.exclusive".

Signed-off-by: Chen Ridong <chenridong@huawei.com>
---
 kernel/cgroup/cpuset.c | 42 +++++++++++++++++++++++-------------------
 1 file changed, 23 insertions(+), 19 deletions(-)

diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index e34fd6108b06..fdd5346616d3 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -80,6 +80,7 @@ enum prs_errcode {
 	PERR_HOTPLUG,
 	PERR_CPUSEMPTY,
 	PERR_HKEEPING,
+	PERR_PMT,
 };
 
 static const char * const perr_strings[] = {
@@ -91,6 +92,7 @@ static const char * const perr_strings[] = {
 	[PERR_HOTPLUG]   = "No cpu available due to hotplug",
 	[PERR_CPUSEMPTY] = "cpuset.cpus and cpuset.cpus.exclusive are empty",
 	[PERR_HKEEPING]  = "partition config conflicts with housekeeping setup",
+	[PERR_PMT]       = "Enable partition not permitted",
 };
 
 struct cpuset {
@@ -1669,7 +1671,7 @@ static int remote_partition_enable(struct cpuset *cs, int new_prs,
 	 * The user must have sysadmin privilege.
 	 */
 	if (!capable(CAP_SYS_ADMIN))
-		return 0;
+		return PERR_PMT;
 
 	/*
 	 * The requested exclusive_cpus must not be allocated to other
@@ -1683,7 +1685,7 @@ static int remote_partition_enable(struct cpuset *cs, int new_prs,
 	if (cpumask_empty(tmp->new_cpus) ||
 	    cpumask_intersects(tmp->new_cpus, subpartitions_cpus) ||
 	    cpumask_subset(top_cpuset.effective_cpus, tmp->new_cpus))
-		return 0;
+		return PERR_INVCPUS;
 
 	spin_lock_irq(&callback_lock);
 	isolcpus_updated = partition_xcpus_add(new_prs, NULL, tmp->new_cpus);
@@ -1698,7 +1700,7 @@ static int remote_partition_enable(struct cpuset *cs, int new_prs,
 	 */
 	update_tasks_cpumask(&top_cpuset, tmp->new_cpus);
 	update_sibling_cpumasks(&top_cpuset, NULL, tmp);
-	return 1;
+	return 0;
 }
 
 /*
@@ -3151,24 +3153,26 @@ static int update_prstate(struct cpuset *cs, int new_prs)
 		goto out;
 
 	if (!old_prs) {
-		enum partition_cmd cmd = (new_prs == PRS_ROOT)
-				       ? partcmd_enable : partcmd_enablei;
-
 		/*
-		 * cpus_allowed and exclusive_cpus cannot be both empty.
-		 */
-		if (xcpus_empty(cs)) {
-			err = PERR_CPUSEMPTY;
-			goto out;
-		}
+		* If parent is valid partition, enable local partiion.
+		* Otherwise, enable a remote partition.
+		*/
+		if (is_partition_valid(parent)) {
+			enum partition_cmd cmd = (new_prs == PRS_ROOT)
+					       ? partcmd_enable : partcmd_enablei;
 
-		err = update_parent_effective_cpumask(cs, cmd, NULL, &tmpmask);
-		/*
-		 * If an attempt to become local partition root fails,
-		 * try to become a remote partition root instead.
-		 */
-		if (err && remote_partition_enable(cs, new_prs, &tmpmask))
-			err = 0;
+			/*
+			 * cpus_allowed and exclusive_cpus cannot be both empty.
+			 */
+			if (xcpus_empty(cs)) {
+				err = PERR_CPUSEMPTY;
+				goto out;
+			}
+
+			err = update_parent_effective_cpumask(cs, cmd, NULL, &tmpmask);
+		} else {
+			err = remote_partition_enable(cs, new_prs, &tmpmask);
+		}
 	} else if (old_prs && new_prs) {
 		/*
 		 * A change in load balance state only, no change in cpumasks.
-- 
2.34.1
Re: [PATCH -next 1/3] cgroup/cpuset: Correct invalid remote parition prs
Posted by Waiman Long 1 year, 5 months ago
On 8/16/24 04:27, Chen Ridong wrote:
> When enable a remote partition, I found that:
>
> cd /sys/fs/cgroup/
> mkdir test
> mkdir test/test1
> echo +cpuset > cgroup.subtree_control
> echo +cpuset >  test/cgroup.subtree_control
> echo 3 > test/test1/cpuset.cpus
> echo root > test/test1/cpuset.cpus.partition
> cat test/test1/cpuset.cpus.partition
> root invalid (Parent is not a partition root)
>
> The parent of a remote partition could not be a root. This is due to the
> emtpy effective_xcpus. It would be better to prompt the message "invalid
> cpu list in cpuset.cpus.exclusive".
>
> Signed-off-by: Chen Ridong <chenridong@huawei.com>
> ---
>   kernel/cgroup/cpuset.c | 42 +++++++++++++++++++++++-------------------
>   1 file changed, 23 insertions(+), 19 deletions(-)
>
> diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
> index e34fd6108b06..fdd5346616d3 100644
> --- a/kernel/cgroup/cpuset.c
> +++ b/kernel/cgroup/cpuset.c
> @@ -80,6 +80,7 @@ enum prs_errcode {
>   	PERR_HOTPLUG,
>   	PERR_CPUSEMPTY,
>   	PERR_HKEEPING,
> +	PERR_PMT,
>   };
>   
>   static const char * const perr_strings[] = {
> @@ -91,6 +92,7 @@ static const char * const perr_strings[] = {
>   	[PERR_HOTPLUG]   = "No cpu available due to hotplug",
>   	[PERR_CPUSEMPTY] = "cpuset.cpus and cpuset.cpus.exclusive are empty",
>   	[PERR_HKEEPING]  = "partition config conflicts with housekeeping setup",
> +	[PERR_PMT]       = "Enable partition not permitted",
>   };
>   
>   struct cpuset {
> @@ -1669,7 +1671,7 @@ static int remote_partition_enable(struct cpuset *cs, int new_prs,
>   	 * The user must have sysadmin privilege.
>   	 */
>   	if (!capable(CAP_SYS_ADMIN))
> -		return 0;
> +		return PERR_PMT;
>   
>   	/*
>   	 * The requested exclusive_cpus must not be allocated to other
> @@ -1683,7 +1685,7 @@ static int remote_partition_enable(struct cpuset *cs, int new_prs,
>   	if (cpumask_empty(tmp->new_cpus) ||
>   	    cpumask_intersects(tmp->new_cpus, subpartitions_cpus) ||
>   	    cpumask_subset(top_cpuset.effective_cpus, tmp->new_cpus))
> -		return 0;
> +		return PERR_INVCPUS;
>   
>   	spin_lock_irq(&callback_lock);
>   	isolcpus_updated = partition_xcpus_add(new_prs, NULL, tmp->new_cpus);
> @@ -1698,7 +1700,7 @@ static int remote_partition_enable(struct cpuset *cs, int new_prs,
>   	 */
>   	update_tasks_cpumask(&top_cpuset, tmp->new_cpus);
>   	update_sibling_cpumasks(&top_cpuset, NULL, tmp);
> -	return 1;
> +	return 0;
>   }

Since you are changing the meaning of the function returned value, you 
should also update the return value comment as well.

>   
>   /*
> @@ -3151,24 +3153,26 @@ static int update_prstate(struct cpuset *cs, int new_prs)
>   		goto out;
>   
>   	if (!old_prs) {
> -		enum partition_cmd cmd = (new_prs == PRS_ROOT)
> -				       ? partcmd_enable : partcmd_enablei;
> -
>   		/*
> -		 * cpus_allowed and exclusive_cpus cannot be both empty.
> -		 */
> -		if (xcpus_empty(cs)) {
> -			err = PERR_CPUSEMPTY;
> -			goto out;
> -		}
> +		* If parent is valid partition, enable local partiion.
> +		* Otherwise, enable a remote partition.
> +		*/
> +		if (is_partition_valid(parent)) {
> +			enum partition_cmd cmd = (new_prs == PRS_ROOT)
> +					       ? partcmd_enable : partcmd_enablei;
>   
> -		err = update_parent_effective_cpumask(cs, cmd, NULL, &tmpmask);
> -		/*
> -		 * If an attempt to become local partition root fails,
> -		 * try to become a remote partition root instead.
> -		 */
> -		if (err && remote_partition_enable(cs, new_prs, &tmpmask))
> -			err = 0;
> +			/*
> +			 * cpus_allowed and exclusive_cpus cannot be both empty.
> +			 */
> +			if (xcpus_empty(cs)) {
> +				err = PERR_CPUSEMPTY;
> +				goto out;
> +			}

The xcpus_empty() check should be done for both local and remote partition.

Cheers,
Longman

> +
> +			err = update_parent_effective_cpumask(cs, cmd, NULL, &tmpmask);
> +		} else {
> +			err = remote_partition_enable(cs, new_prs, &tmpmask);
> +		}
>   	} else if (old_prs && new_prs) {
>   		/*
>   		 * A change in load balance state only, no change in cpumasks.
Re: [PATCH -next 1/3] cgroup/cpuset: Correct invalid remote parition prs
Posted by Waiman Long 1 year, 5 months ago
On 8/18/24 22:14, Waiman Long wrote:
>
> On 8/16/24 04:27, Chen Ridong wrote:
>> When enable a remote partition, I found that:
>>
>> cd /sys/fs/cgroup/
>> mkdir test
>> mkdir test/test1
>> echo +cpuset > cgroup.subtree_control
>> echo +cpuset >  test/cgroup.subtree_control
>> echo 3 > test/test1/cpuset.cpus
>> echo root > test/test1/cpuset.cpus.partition
>> cat test/test1/cpuset.cpus.partition
>> root invalid (Parent is not a partition root)
>>
>> The parent of a remote partition could not be a root. This is due to the
>> emtpy effective_xcpus. It would be better to prompt the message "invalid
>> cpu list in cpuset.cpus.exclusive".
>>
>> Signed-off-by: Chen Ridong <chenridong@huawei.com>
>> ---
>>   kernel/cgroup/cpuset.c | 42 +++++++++++++++++++++++-------------------
>>   1 file changed, 23 insertions(+), 19 deletions(-)
>>
>> diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
>> index e34fd6108b06..fdd5346616d3 100644
>> --- a/kernel/cgroup/cpuset.c
>> +++ b/kernel/cgroup/cpuset.c
>> @@ -80,6 +80,7 @@ enum prs_errcode {
>>       PERR_HOTPLUG,
>>       PERR_CPUSEMPTY,
>>       PERR_HKEEPING,
>> +    PERR_PMT,

One more thing, the "PMT" acronym for the error code is hard to decode. 
I will suggest you either use the "PERMISSION" or "ACCESS" like the 
EACCESS errno.

Cheers,
Longman

>>   };
>>     static const char * const perr_strings[] = {
>> @@ -91,6 +92,7 @@ static const char * const perr_strings[] = {
>>       [PERR_HOTPLUG]   = "No cpu available due to hotplug",
>>       [PERR_CPUSEMPTY] = "cpuset.cpus and cpuset.cpus.exclusive are 
>> empty",
>>       [PERR_HKEEPING]  = "partition config conflicts with 
>> housekeeping setup",
>> +    [PERR_PMT]       = "Enable partition not permitted",
>>   };
>>     struct cpuset {
>> @@ -1669,7 +1671,7 @@ static int remote_partition_enable(struct 
>> cpuset *cs, int new_prs,
>>        * The user must have sysadmin privilege.
>>        */
>>       if (!capable(CAP_SYS_ADMIN))
>> -        return 0;
>> +        return PERR_PMT;
>>         /*
>>        * The requested exclusive_cpus must not be allocated to other
>> @@ -1683,7 +1685,7 @@ static int remote_partition_enable(struct 
>> cpuset *cs, int new_prs,
>>       if (cpumask_empty(tmp->new_cpus) ||
>>           cpumask_intersects(tmp->new_cpus, subpartitions_cpus) ||
>>           cpumask_subset(top_cpuset.effective_cpus, tmp->new_cpus))
>> -        return 0;
>> +        return PERR_INVCPUS;
>>         spin_lock_irq(&callback_lock);
>>       isolcpus_updated = partition_xcpus_add(new_prs, NULL, 
>> tmp->new_cpus);
>> @@ -1698,7 +1700,7 @@ static int remote_partition_enable(struct 
>> cpuset *cs, int new_prs,
>>        */
>>       update_tasks_cpumask(&top_cpuset, tmp->new_cpus);
>>       update_sibling_cpumasks(&top_cpuset, NULL, tmp);
>> -    return 1;
>> +    return 0;
>>   }
>
> Since you are changing the meaning of the function returned value, you 
> should also update the return value comment as well.
>
>>     /*
>> @@ -3151,24 +3153,26 @@ static int update_prstate(struct cpuset *cs, 
>> int new_prs)
>>           goto out;
>>         if (!old_prs) {
>> -        enum partition_cmd cmd = (new_prs == PRS_ROOT)
>> -                       ? partcmd_enable : partcmd_enablei;
>> -
>>           /*
>> -         * cpus_allowed and exclusive_cpus cannot be both empty.
>> -         */
>> -        if (xcpus_empty(cs)) {
>> -            err = PERR_CPUSEMPTY;
>> -            goto out;
>> -        }
>> +        * If parent is valid partition, enable local partiion.
>> +        * Otherwise, enable a remote partition.
>> +        */
>> +        if (is_partition_valid(parent)) {
>> +            enum partition_cmd cmd = (new_prs == PRS_ROOT)
>> +                           ? partcmd_enable : partcmd_enablei;
>>   -        err = update_parent_effective_cpumask(cs, cmd, NULL, 
>> &tmpmask);
>> -        /*
>> -         * If an attempt to become local partition root fails,
>> -         * try to become a remote partition root instead.
>> -         */
>> -        if (err && remote_partition_enable(cs, new_prs, &tmpmask))
>> -            err = 0;
>> +            /*
>> +             * cpus_allowed and exclusive_cpus cannot be both empty.
>> +             */
>> +            if (xcpus_empty(cs)) {
>> +                err = PERR_CPUSEMPTY;
>> +                goto out;
>> +            }
>
> The xcpus_empty() check should be done for both local and remote 
> partition.
>
> Cheers,
> Longman
>
>> +
>> +            err = update_parent_effective_cpumask(cs, cmd, NULL, 
>> &tmpmask);
>> +        } else {
>> +            err = remote_partition_enable(cs, new_prs, &tmpmask);
>> +        }
>>       } else if (old_prs && new_prs) {
>>           /*
>>            * A change in load balance state only, no change in cpumasks.

Re: [PATCH -next 1/3] cgroup/cpuset: Correct invalid remote parition prs
Posted by chenridong 1 year, 5 months ago

On 2024/8/19 10:18, Waiman Long wrote:
> On 8/18/24 22:14, Waiman Long wrote:
>>
>> On 8/16/24 04:27, Chen Ridong wrote:
>>> When enable a remote partition, I found that:
>>>
>>> cd /sys/fs/cgroup/
>>> mkdir test
>>> mkdir test/test1
>>> echo +cpuset > cgroup.subtree_control
>>> echo +cpuset >  test/cgroup.subtree_control
>>> echo 3 > test/test1/cpuset.cpus
>>> echo root > test/test1/cpuset.cpus.partition
>>> cat test/test1/cpuset.cpus.partition
>>> root invalid (Parent is not a partition root)
>>>
>>> The parent of a remote partition could not be a root. This is due to the
>>> emtpy effective_xcpus. It would be better to prompt the message "invalid
>>> cpu list in cpuset.cpus.exclusive".
>>>
>>> Signed-off-by: Chen Ridong <chenridong@huawei.com>
>>> ---
>>>   kernel/cgroup/cpuset.c | 42 +++++++++++++++++++++++-------------------
>>>   1 file changed, 23 insertions(+), 19 deletions(-)
>>>
>>> diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
>>> index e34fd6108b06..fdd5346616d3 100644
>>> --- a/kernel/cgroup/cpuset.c
>>> +++ b/kernel/cgroup/cpuset.c
>>> @@ -80,6 +80,7 @@ enum prs_errcode {
>>>       PERR_HOTPLUG,
>>>       PERR_CPUSEMPTY,
>>>       PERR_HKEEPING,
>>> +    PERR_PMT,
> 
> One more thing, the "PMT" acronym for the error code is hard to decode. 
> I will suggest you either use the "PERMISSION" or "ACCESS" like the 
> EACCESS errno.
> 
> Cheers,
> Longman
> 
Thanks, will do.
>>>   };
>>>     static const char * const perr_strings[] = {
>>> @@ -91,6 +92,7 @@ static const char * const perr_strings[] = {
>>>       [PERR_HOTPLUG]   = "No cpu available due to hotplug",
>>>       [PERR_CPUSEMPTY] = "cpuset.cpus and cpuset.cpus.exclusive are 
>>> empty",
>>>       [PERR_HKEEPING]  = "partition config conflicts with 
>>> housekeeping setup",
>>> +    [PERR_PMT]       = "Enable partition not permitted",
>>>   };
>>>     struct cpuset {
>>> @@ -1669,7 +1671,7 @@ static int remote_partition_enable(struct 
>>> cpuset *cs, int new_prs,
>>>        * The user must have sysadmin privilege.
>>>        */
>>>       if (!capable(CAP_SYS_ADMIN))
>>> -        return 0;
>>> +        return PERR_PMT;
>>>         /*
>>>        * The requested exclusive_cpus must not be allocated to other
>>> @@ -1683,7 +1685,7 @@ static int remote_partition_enable(struct 
>>> cpuset *cs, int new_prs,
>>>       if (cpumask_empty(tmp->new_cpus) ||
>>>           cpumask_intersects(tmp->new_cpus, subpartitions_cpus) ||
>>>           cpumask_subset(top_cpuset.effective_cpus, tmp->new_cpus))
>>> -        return 0;
>>> +        return PERR_INVCPUS;
>>>         spin_lock_irq(&callback_lock);
>>>       isolcpus_updated = partition_xcpus_add(new_prs, NULL, 
>>> tmp->new_cpus);
>>> @@ -1698,7 +1700,7 @@ static int remote_partition_enable(struct 
>>> cpuset *cs, int new_prs,
>>>        */
>>>       update_tasks_cpumask(&top_cpuset, tmp->new_cpus);
>>>       update_sibling_cpumasks(&top_cpuset, NULL, tmp);
>>> -    return 1;
>>> +    return 0;
>>>   }
>>
>> Since you are changing the meaning of the function returned value, you 
>> should also update the return value comment as well.
>>
Will do.
>>>     /*
>>> @@ -3151,24 +3153,26 @@ static int update_prstate(struct cpuset *cs, 
>>> int new_prs)
>>>           goto out;
>>>         if (!old_prs) {
>>> -        enum partition_cmd cmd = (new_prs == PRS_ROOT)
>>> -                       ? partcmd_enable : partcmd_enablei;
>>> -
>>>           /*
>>> -         * cpus_allowed and exclusive_cpus cannot be both empty.
>>> -         */
>>> -        if (xcpus_empty(cs)) {
>>> -            err = PERR_CPUSEMPTY;
>>> -            goto out;
>>> -        }
>>> +        * If parent is valid partition, enable local partiion.
>>> +        * Otherwise, enable a remote partition.
>>> +        */
>>> +        if (is_partition_valid(parent)) {
>>> +            enum partition_cmd cmd = (new_prs == PRS_ROOT)
>>> +                           ? partcmd_enable : partcmd_enablei;
>>>   -        err = update_parent_effective_cpumask(cs, cmd, NULL, 
>>> &tmpmask);
>>> -        /*
>>> -         * If an attempt to become local partition root fails,
>>> -         * try to become a remote partition root instead.
>>> -         */
>>> -        if (err && remote_partition_enable(cs, new_prs, &tmpmask))
>>> -            err = 0;
>>> +            /*
>>> +             * cpus_allowed and exclusive_cpus cannot be both empty.
>>> +             */
>>> +            if (xcpus_empty(cs)) {
>>> +                err = PERR_CPUSEMPTY;
>>> +                goto out;
>>> +            }
>>
>> The xcpus_empty() check should be done for both local and remote 
>> partition.
>>
>> Cheers,
>> Longman
>>
Thanks, I will do it at V2.

Thanks,
Ridong
>>> +
>>> +            err = update_parent_effective_cpumask(cs, cmd, NULL, 
>>> &tmpmask);
>>> +        } else {
>>> +            err = remote_partition_enable(cs, new_prs, &tmpmask);
>>> +        }
>>>       } else if (old_prs && new_prs) {
>>>           /*
>>>            * A change in load balance state only, no change in cpumasks.
> 
>