Re: [PATCH] zsmalloc: reset compaction source zspage pointer after putback_zspage()

From: Yosry Ahmed <yosryahmed@google.com>
To: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Yu Zhao <yuzhao@google.com>, Minchan Kim <minchan@kernel.org>,
	linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [PATCH] zsmalloc: reset compaction source zspage pointer after putback_zspage()
Date: Mon, 17 Apr 2023 04:43:04 -0700	[thread overview]
Message-ID: <CAJD7tkYX4JEFwk3yjmMLMCLVPF=8UfFbv1qaPAufcQ++z8XqDQ@mail.gmail.com> (raw)
In-Reply-To: <20230417050140.1653593-1-senozhatsky@chromium.org>

Hi Sergey,

On Sun, Apr 16, 2023 at 10:01 PM Sergey Senozhatsky
<senozhatsky@chromium.org> wrote:
>
> Fixup.

I think the original patch landed in mm-stable already, so we might
want a proper commit log and fixes tag.

I suspect we want:
Fixes: 5a845e9f2d66 ("zsmalloc: rework compaction algorithm")

>
> Reported-by: Yu Zhao <yuzhao@google.com>
> Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>

Otherwise, LGTM.

Reviewed-by: Yosry Ahmed <yosryahmed@google.com>

> ---
>  mm/zsmalloc.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
> index aea50e2aa350..cc81dfba05a0 100644
> --- a/mm/zsmalloc.c
> +++ b/mm/zsmalloc.c
> @@ -2239,8 +2239,8 @@ static unsigned long __zs_compact(struct zs_pool *pool,
>                 if (fg == ZS_INUSE_RATIO_0) {
>                         free_zspage(pool, class, src_zspage);
>                         pages_freed += class->pages_per_zspage;
> -                       src_zspage = NULL;
>                 }
> +               src_zspage = NULL;
>
>                 if (get_fullness_group(class, dst_zspage) == ZS_INUSE_RATIO_100
>                     || spin_is_contended(&pool->lock)) {
> --
> 2.40.0.634.g4ca3ef3211-goog
>