On Tue, 19 Dec 2017 20:45:17 +0300 Aliaksei Karaliou <akaraliou.dev@xxxxxxxxx> wrote:
> >>> So what will happen if the pool is alive and used without any shrinker?
> >>> How do objects get freed?
> >> we use shrinker for "optional" de-fragmentation of zsmalloc pools. we
> >> don't free any objects from that path. just move them around within their
> >> size classes - to consolidate objects and to, may be, free unused pages
> >> [but we first need to make them "unused"]. it's not a mandatory thing for
> >> zsmalloc, we are just trying to be nice.
> > OK, it smells like an abuse of the API but please add a comment
> > clarifying that.
> >
> > Thanks!
> I can update the existing comment to be like that:
> /*
> * Not critical since shrinker is only used to trigger internal
> * de-fragmentation of the pool which is pretty optional thing.
> * If registration fails we still can use the pool normally and
> * user can trigger compaction manually. Thus, ignore return code.
> */
>
> Sergey, does this sound well to you ? Or not clear enough, Michal ?
I did this:
From: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Subject: mm-zsmalloc-simplify-shrinker-init-destroy-fix
update comment (Aliaksei), make zs_register_shrinker() return void
Cc: Aliaksei Karaliou <akaraliou.dev@xxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxxxx>
Cc: Minchan Kim <minchan@xxxxxxxxxx>
Cc: Sergey Senozhatsky <sergey.senozhatsky@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/zsmalloc.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)
diff -puN mm/zsmalloc.c~mm-zsmalloc-simplify-shrinker-init-destroy-fix mm/zsmalloc.c
--- a/mm/zsmalloc.c~mm-zsmalloc-simplify-shrinker-init-destroy-fix
+++ a/mm/zsmalloc.c
@@ -2323,14 +2323,14 @@ static void zs_unregister_shrinker(struc
unregister_shrinker(&pool->shrinker);
}
-static int zs_register_shrinker(struct zs_pool *pool)
+static void zs_register_shrinker(struct zs_pool *pool)
{
pool->shrinker.scan_objects = zs_shrinker_scan;
pool->shrinker.count_objects = zs_shrinker_count;
pool->shrinker.batch = 0;
pool->shrinker.seeks = DEFAULT_SEEKS;
- return register_shrinker(&pool->shrinker);
+ register_shrinker(&pool->shrinker);
}
/**
@@ -2419,10 +2419,12 @@ struct zs_pool *zs_create_pool(const cha
goto err;
/*
- * Not critical, we still can use the pool
- * and user can trigger compaction manually.
+ * Not critical since shrinker is only used to trigger internal
+ * defragmentation of the pool which is pretty optional thing. If
+ * registration fails we still can use the pool normally and user can
+ * trigger compaction manually. Thus, ignore return code.
*/
- (void) zs_register_shrinker(pool);
+ zs_register_shrinker(pool);
return pool;
_
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
