Re: [PATCH] mm/khugepaged: Refactor mm_khugepaged_scan_file tracepoint to remove filename from function call

[Yang Shi <shy828301@gmail.com>]

On Tue, Oct 25, 2022 at 9:45 PM Gautam Menghani
<gautammenghani201@gmail.com> wrote:
>
> Refactor the mm_khugepaged_scan_file tracepoint to move filename
> dereference to the tracepoint definition, for maintaing consistency with
> other tracepoints[1].
>
> [1]:lore.kernel.org/lkml/20221024111621.3ba17e2c@gandalf.local.home/
>
> Signed-off-by: Gautam Menghani <gautammenghani201@gmail.com>

Reviewed-by: Yang Shi <shy828301@gmail.com>

> ---
>  include/trace/events/huge_memory.h | 8 ++++----
>  mm/khugepaged.c                    | 3 +--
>  2 files changed, 5 insertions(+), 6 deletions(-)
>
> diff --git a/include/trace/events/huge_memory.h b/include/trace/events/huge_memory.h
> index 935af4947917..760455dfa860 100644
> --- a/include/trace/events/huge_memory.h
> +++ b/include/trace/events/huge_memory.h
> @@ -171,15 +171,15 @@ TRACE_EVENT(mm_collapse_huge_page_swapin,
>
>  TRACE_EVENT(mm_khugepaged_scan_file,
>
> -       TP_PROTO(struct mm_struct *mm, struct page *page, const char *filename,
> +       TP_PROTO(struct mm_struct *mm, struct page *page, struct file *file,
>                  int present, int swap, int result),
>
> -       TP_ARGS(mm, page, filename, present, swap, result),
> +       TP_ARGS(mm, page, file, present, swap, result),
>
>         TP_STRUCT__entry(
>                 __field(struct mm_struct *, mm)
>                 __field(unsigned long, pfn)
> -               __string(filename, filename)
> +               __string(filename, file->f_path.dentry->d_iname)
>                 __field(int, present)
>                 __field(int, swap)
>                 __field(int, result)
> @@ -188,7 +188,7 @@ TRACE_EVENT(mm_khugepaged_scan_file,
>         TP_fast_assign(
>                 __entry->mm = mm;
>                 __entry->pfn = page ? page_to_pfn(page) : -1;
> -               __assign_str(filename, filename);
> +               __assign_str(filename, file->f_path.dentry->d_iname);
>                 __entry->present = present;
>                 __entry->swap = swap;
>                 __entry->result = result;
> diff --git a/mm/khugepaged.c b/mm/khugepaged.c
> index 4734315f7940..9808a899f9f7 100644
> --- a/mm/khugepaged.c
> +++ b/mm/khugepaged.c
> @@ -2157,8 +2157,7 @@ static int hpage_collapse_scan_file(struct mm_struct *mm, unsigned long addr,
>                 }
>         }
>
> -       trace_mm_khugepaged_scan_file(mm, page, file->f_path.dentry->d_iname,
> -                                     present, swap, result);
> +       trace_mm_khugepaged_scan_file(mm, page, file, present, swap, result);
>         return result;
>  }
>  #else
> --
> 2.34.1
>