On Mon, Mar 31, 2025 at 12:07:12PM +0200, Jan Kara wrote:
> On Sat 29-03-25 09:42:18, Christian Brauner wrote:
> > Use a common iterator for all callbacks. We could go for something even
> > more elaborate (advance step-by-step similar to iov_iter) but I really
> > don't think this is warranted.
> >
> > Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx>
>
> Looks good, one nit below. With that fixed feel free to add:
>
> Reviewed-by: Jan Kara <jack@xxxxxxx>
>
> > +#define invalid_super list_entry_is_head
>
> Why do you have this invalid_super define? I find it rather confusing in
> the loop below and list_entry_is_head() would be much more
> understandable...
Fair, I just wanted a shorter name but I'll change it to
list_entry_is_head() and push it out.
>
> Honza
>
> > +
> > +static void __iterate_supers(void (*f)(struct super_block *, void *), void *arg,
> > + enum super_iter_flags_t flags)
> > {
> > struct super_block *sb, *p = NULL;
> > + bool excl = flags & SUPER_ITER_EXCL;
> >
> > - spin_lock(&sb_lock);
> > - list_for_each_entry(sb, &super_blocks, s_list) {
> > - bool locked;
> > + guard(spinlock)(&sb_lock);
> >
> > + for (sb = first_super(flags); !invalid_super(sb, &super_blocks, s_list);
> > + sb = next_super(sb, flags)) {
> > if (super_flags(sb, SB_DYING))
> > continue;
> > sb->s_count++;
> > spin_unlock(&sb_lock);
> >
> > - locked = super_lock(sb, excl);
> > - if (locked) {
> > + if (flags & SUPER_ITER_UNLOCKED) {
> > + f(sb, arg);
> > + } else if (super_lock(sb, excl)) {
> > f(sb, arg);
> > super_unlock(sb, excl);
> > }
> --
> Jan Kara <jack@xxxxxxxx>
> SUSE Labs, CR
