[Cluster-devel] [PATCH 6/8] gfs2: Rework freeze / thaw logic

[Alexander Aring]

Hi Andreas,

On Mon, Jun 12, 2023 at 12:33 PM Andreas Gruenbacher
<agruenba at redhat.com> wrote:
...
>
> @@ -152,24 +151,18 @@ static void signal_our_withdraw(struct gfs2_sbd *sdp)
>          */
>         clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
>         if (!sb_rdonly(sdp->sd_vfs)) {
> -               struct gfs2_holder freeze_gh;
> -
> -               gfs2_holder_mark_uninitialized(&freeze_gh);
> -               if (sdp->sd_freeze_gl &&
> -                   !gfs2_glock_is_locked_by_me(sdp->sd_freeze_gl)) {
> -                       ret = gfs2_freeze_lock_shared(sdp, &freeze_gh,
> -                                       log_write_allowed ? 0 : LM_FLAG_TRY);
> -                       if (ret == GLR_TRYFAILED)
> -                               ret = 0;
> -               }
> -               if (!ret)
> -                       gfs2_make_fs_ro(sdp);
> +               bool locked = mutex_trylock(&sdp->sd_freeze_mutex);
> +
> +               gfs2_make_fs_ro(sdp);
> +
> +               if (locked)
> +                       mutex_unlock(&sdp->sd_freeze_mutex);

I am not sure if I overlooked something here, for me it looks like the
application does not care about if sd_freeze_mutex is locked or not
because the introduced locked boolean will never be evaluated?

What am I missing here?

- Alex