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References: <20201111051658.18904-1-pankaj.gupta.linux@gmail.com>
 <20201111051658.18904-2-pankaj.gupta.linux@gmail.com> <ee573db1-33d0-b210-7205-4736de007488@molgen.mpg.de>
In-Reply-To: <ee573db1-33d0-b210-7205-4736de007488@molgen.mpg.de>
From:   Pankaj Gupta <pankaj.gupta@cloud.ionos.com>
Date:   Wed, 11 Nov 2020 08:22:19 +0100
Message-ID: <CALzYo30rZYw2r73QZR0q+HZLaHSEZ8BTxy-W-Ad8tKq4mQZozA@mail.gmail.com>
Subject: Re: [PATCH 1/3] md: improve variable names in md_flush_request()
To:     Paul Menzel <pmenzel@molgen.mpg.de>
Cc:     Pankaj Gupta <pankaj.gupta.linux@gmail.com>, song@kernel.org,
        linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org
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Precedence: bulk

Hi Paul,

> >   This patch improves readability by using better variable names
> >   in flush request coalescing logic.
>
> Please do not indent the commit message.

o.k

>
> > Signed-off-by: Pankaj Gupta <pankaj.gupta@cloud.ionos.com>
> > ---
> >   drivers/md/md.c | 8 ++++----
> >   drivers/md/md.h | 6 +++---
> >   2 files changed, 7 insertions(+), 7 deletions(-)
> >
> > diff --git a/drivers/md/md.c b/drivers/md/md.c
> > index 98bac4f304ae..167c80f98533 100644
> > --- a/drivers/md/md.c
> > +++ b/drivers/md/md.c
> > @@ -639,7 +639,7 @@ static void md_submit_flush_data(struct work_struct *ws)
> >        * could wait for this and below md_handle_request could wait for those
> >        * bios because of suspend check
> >        */
> > -     mddev->last_flush = mddev->start_flush;
> > +     mddev->prev_flush_start = mddev->start_flush;
> >       mddev->flush_bio = NULL;
> >       wake_up(&mddev->sb_wait);
> >
> > @@ -660,13 +660,13 @@ static void md_submit_flush_data(struct work_struct *ws)
> >    */
> >   bool md_flush_request(struct mddev *mddev, struct bio *bio)
> >   {
> > -     ktime_t start = ktime_get_boottime();
> > +     ktime_t req_start = ktime_get_boottime();
> >       spin_lock_irq(&mddev->lock);
> >       wait_event_lock_irq(mddev->sb_wait,
> >                           !mddev->flush_bio ||
> > -                         ktime_after(mddev->last_flush, start),
> > +                         ktime_after(mddev->prev_flush_start, req_start),
> >                           mddev->lock);
> > -     if (!ktime_after(mddev->last_flush, start)) {
> > +     if (!ktime_after(mddev->prev_flush_start, req_start)) {
> >               WARN_ON(mddev->flush_bio);
> >               mddev->flush_bio = bio;
> >               bio = NULL;
> > diff --git a/drivers/md/md.h b/drivers/md/md.h
> > index ccfb69868c2e..2292c847f9dd 100644
> > --- a/drivers/md/md.h
> > +++ b/drivers/md/md.h
> > @@ -495,9 +495,9 @@ struct mddev {
> >        */
> >       struct bio *flush_bio;
> >       atomic_t flush_pending;
> > -     ktime_t start_flush, last_flush; /* last_flush is when the last completed
> > -                                       * flush was started.
> > -                                       */
> > +     ktime_t start_flush, prev_flush_start; /* prev_flush_start is when the previous completed
> > +                                             * flush was started.
> > +                                             */
>
> With the new variable name, the comment could even be removed. ;-)
>
> >       struct work_struct flush_work;
> >       struct work_struct event_work;  /* used by dm to report failure event */
> >       mempool_t *serial_info_pool;
>
> Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de>

Thanks,
Pankaj
>
>
> Kind regards,
>
> Paul