[PATCH net-next] net: skb: move skb_pp_recycle() to skbuff.c

[PATCH net-next] net: skb: move skb_pp_recycle() to skbuff.c

[Yunsheng Lin]

skb_pp_recycle() is only used by skb_free_head() in
skbuff.c, so move it to skbuff.c.

Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
---
 include/linux/skbuff.h | 7 -------
 net/core/skbuff.c      | 7 +++++++
 2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 9fcf534f2d92..28a7b5fbc7b7 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -5048,12 +5048,5 @@ static inline void skb_mark_for_recycle(struct sk_buff *skb)
 }
 #endif
 
-static inline bool skb_pp_recycle(struct sk_buff *skb, void *data)
-{
-	if (!IS_ENABLED(CONFIG_PAGE_POOL) || !skb->pp_recycle)
-		return false;
-	return page_pool_return_skb_page(virt_to_page(data));
-}
-
 #endif	/* __KERNEL__ */
 #endif	/* _LINUX_SKBUFF_H */
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 1d9719e72f9d..9b3b19816d2d 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -748,6 +748,13 @@ static void skb_clone_fraglist(struct sk_buff *skb)
 		skb_get(list);
 }
 
+static bool skb_pp_recycle(struct sk_buff *skb, void *data)
+{
+	if (!IS_ENABLED(CONFIG_PAGE_POOL) || !skb->pp_recycle)
+		return false;
+	return page_pool_return_skb_page(virt_to_page(data));
+}
+
 static void skb_free_head(struct sk_buff *skb)
 {
 	unsigned char *head = skb->head;
-- 
2.33.0

Re: [PATCH net-next] net: skb: move skb_pp_recycle() to skbuff.c

[Ilias Apalodimas]

Hi Yungsheng

On Fri, 21 Oct 2022 at 05:58, Yunsheng Lin <linyunsheng@huawei.com> wrote:
>
> skb_pp_recycle() is only used by skb_free_head() in
> skbuff.c, so move it to skbuff.c.
>
> Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
> ---
>  include/linux/skbuff.h | 7 -------
>  net/core/skbuff.c      | 7 +++++++
>  2 files changed, 7 insertions(+), 7 deletions(-)
>
> diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
> index 9fcf534f2d92..28a7b5fbc7b7 100644
> --- a/include/linux/skbuff.h
> +++ b/include/linux/skbuff.h
> @@ -5048,12 +5048,5 @@ static inline void skb_mark_for_recycle(struct sk_buff *skb)
>  }
>  #endif
>
> -static inline bool skb_pp_recycle(struct sk_buff *skb, void *data)
> -{
> -       if (!IS_ENABLED(CONFIG_PAGE_POOL) || !skb->pp_recycle)
> -               return false;
> -       return page_pool_return_skb_page(virt_to_page(data));
> -}
> -
>  #endif /* __KERNEL__ */
>  #endif /* _LINUX_SKBUFF_H */
> diff --git a/net/core/skbuff.c b/net/core/skbuff.c
> index 1d9719e72f9d..9b3b19816d2d 100644
> --- a/net/core/skbuff.c
> +++ b/net/core/skbuff.c
> @@ -748,6 +748,13 @@ static void skb_clone_fraglist(struct sk_buff *skb)
>                 skb_get(list);
>  }
>
> +static bool skb_pp_recycle(struct sk_buff *skb, void *data)
> +{
> +       if (!IS_ENABLED(CONFIG_PAGE_POOL) || !skb->pp_recycle)
> +               return false;
> +       return page_pool_return_skb_page(virt_to_page(data));
> +}
> +

Any particular reason you are removing the inline hint here?  Doing it
like this will add an extra function call for every packet (assuming
the compiler decided to inline the previous version)

Thanks
/Ilias
>  static void skb_free_head(struct sk_buff *skb)
>  {
>         unsigned char *head = skb->head;
> --
> 2.33.0
>

Re: [PATCH net-next] net: skb: move skb_pp_recycle() to skbuff.c

[Jakub Kicinski]

On Fri, 21 Oct 2022 09:02:36 +0300 Ilias Apalodimas wrote:
> > +static bool skb_pp_recycle(struct sk_buff *skb, void *data)
> > +{
> > +       if (!IS_ENABLED(CONFIG_PAGE_POOL) || !skb->pp_recycle)
> > +               return false;
> > +       return page_pool_return_skb_page(virt_to_page(data));
> > +}
> 
> Any particular reason you are removing the inline hint here? 

It's recommended in networking to avoid using the inline keyword
unless someone actually checked the compiler output and found the
compiler is being stupid. I don't know the full history of this
recommendation tho.

> Doing it like this will add an extra function call for every packet
> (assuming the compiler decided to inline the previous version)

Should be fine, tiny static function with one caller, I'd bet it's
always inlined, even with -Os.

Re: [PATCH net-next] net: skb: move skb_pp_recycle() to skbuff.c

[Ilias Apalodimas]

Hi Jakub 
On Fri, Oct 21, 2022 at 08:51:38AM -0700, Jakub Kicinski wrote:
> On Fri, 21 Oct 2022 09:02:36 +0300 Ilias Apalodimas wrote:
> > > +static bool skb_pp_recycle(struct sk_buff *skb, void *data)
> > > +{
> > > +       if (!IS_ENABLED(CONFIG_PAGE_POOL) || !skb->pp_recycle)
> > > +               return false;
> > > +       return page_pool_return_skb_page(virt_to_page(data));
> > > +}
> > 
> > Any particular reason you are removing the inline hint here? 
> 
> It's recommended in networking to avoid using the inline keyword
> unless someone actually checked the compiler output and found the
> compiler is being stupid. I don't know the full history of this
> recommendation tho.
> 

Ah thanks, didn't know that.  IIRC there was no particular reason.
Probably because the majority of the functions in that header are static
inlines.

> > Doing it like this will add an extra function call for every packet
> > (assuming the compiler decided to inline the previous version)
> 
> Should be fine, tiny static function with one caller, I'd bet it's
> always inlined, even with -Os.

Well it's compilers -- I wouldn't bet,  but fair enough

Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>

Thanks
/Ilias

Re: [PATCH net-next] net: skb: move skb_pp_recycle() to skbuff.c

[patchwork-bot+netdevbpf]

Hello:

This patch was applied to netdev/net-next.git (master)
by David S. Miller <davem@davemloft.net>:

On Fri, 21 Oct 2022 10:58:22 +0800 you wrote:
> skb_pp_recycle() is only used by skb_free_head() in
> skbuff.c, so move it to skbuff.c.
> 
> Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
> ---
>  include/linux/skbuff.h | 7 -------
>  net/core/skbuff.c      | 7 +++++++
>  2 files changed, 7 insertions(+), 7 deletions(-)

Here is the summary with links:
  - [net-next] net: skb: move skb_pp_recycle() to skbuff.c
    https://git.kernel.org/netdev/net-next/c/4727bab4e9bb

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html