On Mon, Dec 15, 2025, 19:59 Sergey Senozhatsky <senozhatsky@chromium.org>
wrote:

> On (25/12/15 17:31), Brian Geffon wrote:
> [..]
> > >  struct zram_table_entry {
> > >         unsigned long handle;
> > > -       unsigned long flags;
> > > +       union {
> > > +               unsigned long __lock;
> > > +               struct attr {
> > > +                       u32 flags;
> > >  #ifdef CONFIG_ZRAM_TRACK_ENTRY_ACTIME
> > > -       ktime_t ac_time;
> > > +                       u32 ac_time;
> > >  #endif
> >
> > Why not just always enable CONFIG_ZRAM_TRACK_ENTRY_ACTIME now that it
> > doesn't consume any additional space?
>
> It's "free" only on x64.  On 32bit systems the removal of
> ZRAM_TRACK_ENTRY_ACTIME will unconditionally add 4 bytes
> per zram_table_entry.
>

Yes thanks true. Sounds good to me.


> > Also, why can't we do this with a single unsigned long flags
> > as before and have a simple method that isolates and casts the
> > lower 32bits as a u32?
>
> There are no upper and lower 32 bits in unsigned long on 32bit systems.
>