Re: [PATCH 5/7] mm/khugepaged: use helper macro __ATTR_RW

[Miaohe Lin <linmiaohe@huawei.com>]

On 2022/6/16 5:28, Yang Shi wrote:
> On Sat, Jun 11, 2022 at 1:47 AM Miaohe Lin <linmiaohe@huawei.com> wrote:
>>
>> Use helper macro __ATTR_RW to define the khugepaged attributes. Minor
>> readability improvement.
>>
>> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
>> ---
>>  mm/khugepaged.c | 37 +++++++++++++++----------------------
>>  1 file changed, 15 insertions(+), 22 deletions(-)
>>
>> diff --git a/mm/khugepaged.c b/mm/khugepaged.c
>> index 8e6fad7c7bd9..142e26e4bdbf 100644
>> --- a/mm/khugepaged.c
>> +++ b/mm/khugepaged.c
>> @@ -147,8 +147,7 @@ static ssize_t scan_sleep_millisecs_store(struct kobject *kobj,
>>         return count;
>>  }
>>  static struct kobj_attribute scan_sleep_millisecs_attr =
>> -       __ATTR(scan_sleep_millisecs, 0644, scan_sleep_millisecs_show,
>> -              scan_sleep_millisecs_store);
>> +       __ATTR_RW(scan_sleep_millisecs);
>>
>>  static ssize_t alloc_sleep_millisecs_show(struct kobject *kobj,
>>                                           struct kobj_attribute *attr,
>> @@ -175,8 +174,7 @@ static ssize_t alloc_sleep_millisecs_store(struct kobject *kobj,
>>         return count;
>>  }
>>  static struct kobj_attribute alloc_sleep_millisecs_attr =
>> -       __ATTR(alloc_sleep_millisecs, 0644, alloc_sleep_millisecs_show,
>> -              alloc_sleep_millisecs_store);
>> +       __ATTR_RW(alloc_sleep_millisecs);
>>
>>  static ssize_t pages_to_scan_show(struct kobject *kobj,
>>                                   struct kobj_attribute *attr,
>> @@ -200,8 +198,7 @@ static ssize_t pages_to_scan_store(struct kobject *kobj,
>>         return count;
>>  }
>>  static struct kobj_attribute pages_to_scan_attr =
>> -       __ATTR(pages_to_scan, 0644, pages_to_scan_show,
>> -              pages_to_scan_store);
>> +       __ATTR_RW(pages_to_scan);
>>
>>  static ssize_t pages_collapsed_show(struct kobject *kobj,
>>                                     struct kobj_attribute *attr,
>> @@ -221,13 +218,13 @@ static ssize_t full_scans_show(struct kobject *kobj,
>>  static struct kobj_attribute full_scans_attr =
>>         __ATTR_RO(full_scans);
>>
>> -static ssize_t khugepaged_defrag_show(struct kobject *kobj,
>> +static ssize_t defrag_show(struct kobject *kobj,
>>                                       struct kobj_attribute *attr, char *buf)
> 
> Why do you rename all the functions? Seems unnecessary and less intriguing TBH.

It's because e.g. __ATTR_RW(defrag) expects the defrag_show and defrag_store instead
of khugepaged_defrag_show and khugepaged_defrag_store.

Thanks.

> 
>>  {
>>         return single_hugepage_flag_show(kobj, attr, buf,
>>                                          TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG);
>>  }
>> -static ssize_t khugepaged_defrag_store(struct kobject *kobj,
>> +static ssize_t defrag_store(struct kobject *kobj,
>>                                        struct kobj_attribute *attr,
>>                                        const char *buf, size_t count)
>>  {
>> @@ -235,8 +232,7 @@ static ssize_t khugepaged_defrag_store(struct kobject *kobj,
>>                                  TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG);
>>  }
>>  static struct kobj_attribute khugepaged_defrag_attr =
>> -       __ATTR(defrag, 0644, khugepaged_defrag_show,
>> -              khugepaged_defrag_store);
>> +       __ATTR_RW(defrag);
>>
>>  /*
>>   * max_ptes_none controls if khugepaged should collapse hugepages over
>> @@ -246,13 +242,13 @@ static struct kobj_attribute khugepaged_defrag_attr =
>>   * runs. Increasing max_ptes_none will instead potentially reduce the
>>   * free memory in the system during the khugepaged scan.
>>   */
>> -static ssize_t khugepaged_max_ptes_none_show(struct kobject *kobj,
>> +static ssize_t max_ptes_none_show(struct kobject *kobj,
>>                                              struct kobj_attribute *attr,
>>                                              char *buf)
>>  {
>>         return sysfs_emit(buf, "%u\n", khugepaged_max_ptes_none);
>>  }
>> -static ssize_t khugepaged_max_ptes_none_store(struct kobject *kobj,
>> +static ssize_t max_ptes_none_store(struct kobject *kobj,
>>                                               struct kobj_attribute *attr,
>>                                               const char *buf, size_t count)
>>  {
>> @@ -268,17 +264,16 @@ static ssize_t khugepaged_max_ptes_none_store(struct kobject *kobj,
>>         return count;
>>  }
>>  static struct kobj_attribute khugepaged_max_ptes_none_attr =
>> -       __ATTR(max_ptes_none, 0644, khugepaged_max_ptes_none_show,
>> -              khugepaged_max_ptes_none_store);
>> +       __ATTR_RW(max_ptes_none);
>>
>> -static ssize_t khugepaged_max_ptes_swap_show(struct kobject *kobj,
>> +static ssize_t max_ptes_swap_show(struct kobject *kobj,
>>                                              struct kobj_attribute *attr,
>>                                              char *buf)
>>  {
>>         return sysfs_emit(buf, "%u\n", khugepaged_max_ptes_swap);
>>  }
>>
>> -static ssize_t khugepaged_max_ptes_swap_store(struct kobject *kobj,
>> +static ssize_t max_ptes_swap_store(struct kobject *kobj,
>>                                               struct kobj_attribute *attr,
>>                                               const char *buf, size_t count)
>>  {
>> @@ -295,17 +290,16 @@ static ssize_t khugepaged_max_ptes_swap_store(struct kobject *kobj,
>>  }
>>
>>  static struct kobj_attribute khugepaged_max_ptes_swap_attr =
>> -       __ATTR(max_ptes_swap, 0644, khugepaged_max_ptes_swap_show,
>> -              khugepaged_max_ptes_swap_store);
>> +       __ATTR_RW(max_ptes_swap);
>>
>> -static ssize_t khugepaged_max_ptes_shared_show(struct kobject *kobj,
>> +static ssize_t max_ptes_shared_show(struct kobject *kobj,
>>                                                struct kobj_attribute *attr,
>>                                                char *buf)
>>  {
>>         return sysfs_emit(buf, "%u\n", khugepaged_max_ptes_shared);
>>  }
>>
>> -static ssize_t khugepaged_max_ptes_shared_store(struct kobject *kobj,
>> +static ssize_t max_ptes_shared_store(struct kobject *kobj,
>>                                               struct kobj_attribute *attr,
>>                                               const char *buf, size_t count)
>>  {
>> @@ -322,8 +316,7 @@ static ssize_t khugepaged_max_ptes_shared_store(struct kobject *kobj,
>>  }
>>
>>  static struct kobj_attribute khugepaged_max_ptes_shared_attr =
>> -       __ATTR(max_ptes_shared, 0644, khugepaged_max_ptes_shared_show,
>> -              khugepaged_max_ptes_shared_store);
>> +       __ATTR_RW(max_ptes_shared);
>>
>>  static struct attribute *khugepaged_attr[] = {
>>         &khugepaged_defrag_attr.attr,
>> --
>> 2.23.0
>>
>>
> .
>