Re: [PATCHv2 2/6] zsmalloc: remove stat and fullness enums
From: Yosry Ahmed
Date: Thu Feb 23 2023 - 18:33:32 EST
On Thu, Feb 23, 2023 at 3:11 PM Minchan Kim <minchan@xxxxxxxxxx> wrote:
>
> On Thu, Feb 23, 2023 at 12:04:47PM +0900, Sergey Senozhatsky wrote:
> > The fullness_group enum is nested (sub-enum) within the
> > class_stat_type enum. zsmalloc requires the values in both
> > enums to match, because zsmalloc passes these values to
> > generic functions, e.g. class_stat_inc() and class_stat_dec(),
> > after casting them to integers.
> >
> > Replace these enums (and enum nesting) and use simple defines
> > instead. Also rename some of zsmalloc stats defines, as they
> > sort of clash with zspage object tags.
> >
> > Suggested-by: Yosry Ahmed <yosryahmed@xxxxxxxxxx>
> > Signed-off-by: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
> > ---
> > mm/zsmalloc.c | 104 ++++++++++++++++++++++----------------------------
> > 1 file changed, 45 insertions(+), 59 deletions(-)
> >
> > diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
> > index b57a89ed6f30..38ae8963c0eb 100644
> > --- a/mm/zsmalloc.c
> > +++ b/mm/zsmalloc.c
> > @@ -159,26 +159,18 @@
> > #define ZS_SIZE_CLASSES (DIV_ROUND_UP(ZS_MAX_ALLOC_SIZE - ZS_MIN_ALLOC_SIZE, \
> > ZS_SIZE_CLASS_DELTA) + 1)
> >
> > -enum fullness_group {
> > - ZS_EMPTY,
> > - ZS_ALMOST_EMPTY,
> > - ZS_ALMOST_FULL,
> > - ZS_FULL,
> > - NR_ZS_FULLNESS,
> > -};
> > +#define ZS_EMPTY 0
> > +#define ZS_ALMOST_EMPTY 1
> > +#define ZS_ALMOST_FULL 2
> > +#define ZS_FULL 3
> > +#define ZS_OBJS_ALLOCATED 4
> > +#define ZS_OBJS_INUSE 5
> >
> > -enum class_stat_type {
> > - CLASS_EMPTY,
> > - CLASS_ALMOST_EMPTY,
> > - CLASS_ALMOST_FULL,
> > - CLASS_FULL,
> > - OBJ_ALLOCATED,
> > - OBJ_USED,
> > - NR_ZS_STAT_TYPE,
> > -};
> > +#define NR_ZS_STAT 6
> > +#define NR_ZS_FULLNESS 4
>
> Using define list instead of enum list looks like going backward. :)
>
> Why can't we do this?
>
> enum class_stat_type {
> ZS_EMPTY,
> ZS_ALMOST_EMPTY,
> ZS_ALMOST_FULL,
> ZS_FULL,
> NR_ZS_FULLNESS,
> ZS_OBJ_ALLOCATED = NR_ZS_FULLNESS,
> ZS_OBJ_USED,
> NR_ZS_STAT,
> }
Right, I suggested getting rid of the extra enums, so merging them
into 1 is great.
>
>
> };
> >
> > struct zs_size_stat {
> > - unsigned long objs[NR_ZS_STAT_TYPE];
> > + unsigned long objs[NR_ZS_STAT];
> > };
> >