Re: [PATCH] ASoC: rsnd: remove unnecessary static in rsnd_ssiu_probe()
From: Joe Perches
Date: Mon Jul 17 2017 - 12:31:45 EST
On Mon, 2017-07-17 at 10:30 -0500, Gustavo A. R. Silva wrote:
> Remove unnecessary static on local variable ops.
> Such variable is initialized before being used,
> on every execution path throughout the function.
> The static has no benefit and, removing it reduces
> the code size.
[]
> In the following log you can see the difference in the code size. Also,
> there is a significant difference in the bss segment. This log is the
> output of the size command, before and after the code change:
>
> before:
> text data bss dec hex filename
> 3211 680 64 3955 f73 sound/soc/sh/rcar/ssiu.o
>
> after:
> text data bss dec hex filename
> 3207 592 0 3799 ed7 sound/soc/sh/rcar/ssiu.o
[]
> diff --git a/sound/soc/sh/rcar/ssiu.c b/sound/soc/sh/rcar/ssiu.c
[]
> @@ -250,7 +250,7 @@ int rsnd_ssiu_probe(struct rsnd_priv *priv)
> {
> struct device *dev = rsnd_priv_to_dev(priv);
> struct rsnd_ssiu *ssiu;
> - static struct rsnd_mod_ops *ops;
> + struct rsnd_mod_ops *ops;
> int i, nr, ret;
>
> /* same number to SSI */
I'm not an sh user anymore, but it's curious to me why
the static removal has such a large impact on data size.
Is this for an allyesconfig with debug symbols?
btw: this does compile for x86 and those sizes seem
more sensible.
$ size sound/soc/sh/rcar/ssiu.o* text data bss dec hex filename
1950 248 0 2198 896 sound/soc/sh/rcar/ssiu.o.defconfig.new
1950 248 8 2206 89e sound/soc/sh/rcar/ssiu.o.defconfig.old
2692 248 0 2940 b7c sound/soc/sh/rcar/ssiu.o.allyesconfig.new
2692 248 8 2948 b84 sound/soc/sh/rcar/ssiu.o.allyesconfig.old