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

[Yang Shi]

On Thu, Jun 16, 2022 at 12:07 AM Miaohe Lin <linmiaohe@xxxxxxxxxx> wrote:
>
> On 2022/6/16 5:28, Yang Shi wrote:
> > On Sat, Jun 11, 2022 at 1:47 AM Miaohe Lin <linmiaohe@xxxxxxxxxx> wrote:
> >>
> >> Use helper macro __ATTR_RW to define the khugepaged attributes. Minor
> >> readability improvement.
> >>
> >> Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
> >> ---
> >>  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.

Aha, I see. I missed this.

Reviewed-by: Yang Shi <shy828301@xxxxxxxxx>

>
> 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
> >>
> >>
> > .
> >
>