Re: [PATCH] cpufreq: speedstep: remove unnecessary static in speedstep_detect_chipset()

From: Rafael J. Wysocki
Date: Fri Jul 21 2017 - 18:46:21 EST


On Tuesday, July 04, 2017 10:09:21 PM Gustavo A. R. Silva wrote:
> Remove unnecessary static on local variable hostbridge.
> 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.
>
> This issue was detected using Coccinelle and the following semantic patch:
>
> @bad exists@
> position p;
> identifier x;
> type T;
> @@
>
> static T x@p;
> ...
> x = <+...x...+>
>
> @@
> identifier x;
> expression e;
> type T;
> position p != bad.p;
> @@
>
> -static
> T x@p;
> ... when != x
> when strict
> ?x = e;
>
> 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
> 5084 3392 256 8732 221c drivers/cpufreq/speedstep-ich.o
>
> after:
> text data bss dec hex filename
> 5062 3304 192 8558 216e drivers/cpufreq/speedstep-ich.o
>
> Signed-off-by: Gustavo A. R. Silva <garsilva@xxxxxxxxxxxxxx>
> ---
> drivers/cpufreq/speedstep-ich.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/cpufreq/speedstep-ich.c b/drivers/cpufreq/speedstep-ich.c
> index b86953a..0412a24 100644
> --- a/drivers/cpufreq/speedstep-ich.c
> +++ b/drivers/cpufreq/speedstep-ich.c
> @@ -207,7 +207,7 @@ static unsigned int speedstep_detect_chipset(void)
> * 8100 which use a pretty old revision of the 82815
> * host bridge. Abort on these systems.
> */
> - static struct pci_dev *hostbridge;
> + struct pci_dev *hostbridge;
>
> hostbridge = pci_get_subsys(PCI_VENDOR_ID_INTEL,
> PCI_DEVICE_ID_INTEL_82815_MC,
>

Applied, thanks!