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References: <20230117170507.2651972-1-arnd@kernel.org>
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From:   Nhat Pham <nphamcs@gmail.com>
Date:   Wed, 18 Jan 2023 11:27:21 -0800
Message-ID: <CAKEwX=OTpY9Wg6YPfADDqeu7FFzciY9o_nNE5dRR3cu_-2ntaw@mail.gmail.com>
Subject: Re: [PATCH] zsmalloc: avoid unused-function warning
To:     Arnd Bergmann <arnd@kernel.org>
Cc:     Minchan Kim <minchan@kernel.org>,
        Sergey Senozhatsky <senozhatsky@chromium.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Arnd Bergmann <arnd@arndb.de>,
        Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        Alexey Romanov <avromanov@sberdevices.ru>,
        "Matthew Wilcox (Oracle)" <willy@infradead.org>,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org
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On Tue, Jan 17, 2023 at 9:05 AM Arnd Bergmann <arnd@kernel.org> wrote:
>
> From: Arnd Bergmann <arnd@arndb.de>
>
> obj_allocated() can be called from two places that are each
> inside of an #ifdef. When both are disabled, the compiler warns:
>
> mm/zsmalloc.c:900:13: error: 'obj_allocated' defined but not used [-Werror=unused-function]
>
> Rather than trying to figure out the correct #ifdef, mark the
> trivial function as 'inline', which implies __maybe_unused and
> shuts up the warning.
>
> Fixes: 796c71ac728e ("zsmalloc: fix a race with deferred_handles storing")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Nhat Pham <nphamcs@gmail.com>
> ---
>  mm/zsmalloc.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
> index 723ed56d3fbb..9d27d9b00bce 100644
> --- a/mm/zsmalloc.c
> +++ b/mm/zsmalloc.c
> @@ -937,7 +937,7 @@ static bool obj_tagged(struct page *page, void *obj, unsigned long *phandle,
>         return true;
>  }
>
> -static bool obj_allocated(struct page *page, void *obj, unsigned long *phandle)
> +static inline bool obj_allocated(struct page *page, void *obj, unsigned long *phandle)
>  {
>         return obj_tagged(page, obj, phandle, OBJ_ALLOCATED_TAG);
>  }
> --
> 2.39.0
>
Tricky one indeed - I definitely missed that. Thanks for the fix!