Re: [PATCH 2/3] mm: mmap_lock: use DECLARE_EVENT_CLASS and DEFINE_EVENT_FN

[Axel Rasmussen <axelrasmussen@google.com>]

Reviewed-by: Axel Rasmussen <axelrasmussen@google.com>

On Thu, Jul 29, 2021 at 2:28 AM Gang Li <ligang.bdlg@bytedance.com> wrote:
>
> By using DECLARE_EVENT_CLASS and TRACE_EVENT_FN, we can save a lot
> of space from duplicate code.
>
> Signed-off-by: Gang Li <ligang.bdlg@bytedance.com>
> ---
>  include/trace/events/mmap_lock.h | 44 +++++++++-----------------------
>  1 file changed, 12 insertions(+), 32 deletions(-)
>
> diff --git a/include/trace/events/mmap_lock.h b/include/trace/events/mmap_lock.h
> index 5f980c92e3e9..b9dd66f9c226 100644
> --- a/include/trace/events/mmap_lock.h
> +++ b/include/trace/events/mmap_lock.h
> @@ -13,7 +13,7 @@ struct mm_struct;
>  extern int trace_mmap_lock_reg(void);
>  extern void trace_mmap_lock_unreg(void);
>
> -TRACE_EVENT_FN(mmap_lock_start_locking,
> +DECLARE_EVENT_CLASS(mmap_lock,
>
>         TP_PROTO(struct mm_struct *mm, const char *memcg_path, bool write),
>
> @@ -36,11 +36,19 @@ TRACE_EVENT_FN(mmap_lock_start_locking,
>                 __entry->mm,
>                 __get_str(memcg_path),
>                 __entry->write ? "true" : "false"
> -       ),
> -
> -       trace_mmap_lock_reg, trace_mmap_lock_unreg
> +   )
>  );
>
> +#define DEFINE_MMAP_LOCK_EVENT(name)                                    \
> +       DEFINE_EVENT_FN(mmap_lock, name,                                \
> +               TP_PROTO(struct mm_struct *mm, const char *memcg_path,  \
> +                       bool write),                                    \
> +               TP_ARGS(mm, memcg_path, write),                         \
> +               trace_mmap_lock_reg, trace_mmap_lock_unreg)
> +
> +DEFINE_MMAP_LOCK_EVENT(mmap_lock_start_locking);
> +DEFINE_MMAP_LOCK_EVENT(mmap_lock_released);
> +
>  TRACE_EVENT_FN(mmap_lock_acquire_returned,
>
>         TP_PROTO(struct mm_struct *mm, const char *memcg_path, bool write,
> @@ -73,34 +81,6 @@ TRACE_EVENT_FN(mmap_lock_acquire_returned,
>         trace_mmap_lock_reg, trace_mmap_lock_unreg
>  );
>
> -TRACE_EVENT_FN(mmap_lock_released,
> -
> -       TP_PROTO(struct mm_struct *mm, const char *memcg_path, bool write),
> -
> -       TP_ARGS(mm, memcg_path, write),
> -
> -       TP_STRUCT__entry(
> -               __field(struct mm_struct *, mm)
> -               __string(memcg_path, memcg_path)
> -               __field(bool, write)
> -       ),
> -
> -       TP_fast_assign(
> -               __entry->mm = mm;
> -               __assign_str(memcg_path, memcg_path);
> -               __entry->write = write;
> -       ),
> -
> -       TP_printk(
> -               "mm=%p memcg_path=%s write=%s",
> -               __entry->mm,
> -               __get_str(memcg_path),
> -               __entry->write ? "true" : "false"
> -       ),
> -
> -       trace_mmap_lock_reg, trace_mmap_lock_unreg
> -);
> -
>  #endif /* _TRACE_MMAP_LOCK_H */
>
>  /* This part must be outside protection */
> --
> 2.20.1
>