| Message ID | 20170705030921.GA18166@embeddedgus (mailing list archive) |
|---|---|
| State | Mainlined |
| Delegated to: | Rafael Wysocki |
| Headers | show |
+ Dominic, On 04-07-17, 22:09, 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@embeddedor.com> > --- > 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; This was added way back Sep'02 by Dominic (@Dominic: I hope you are the same Dominic with a different email id) and I don't think we need it to be static here. Anyway, Dominic can respond on that. commit 1673f3b404bd ("[PATCH] CPUfreq i386 drivers update") (Note: You can find it in history kernel git repo, not the current one). Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Viresh, Gustavo, On Wed, Jul 05, 2017 at 09:23:44AM +0530, Viresh Kumar wrote: > + Dominic, > > On 04-07-17, 22:09, 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@embeddedor.com> > > --- > > 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; > > This was added way back Sep'02 by Dominic (@Dominic: I hope you are the same > Dominic with a different email id) and I don't think we need it to be static > here. Anyway, Dominic can respond on that. > > commit 1673f3b404bd ("[PATCH] CPUfreq i386 drivers update") > > (Note: You can find it in history kernel git repo, not the current one). > > Acked-by: Viresh Kumar <viresh.kumar@linaro.org> indeed, that's me, and the patch seems to be valid and therefore is a useful improvement: Acked-by: Dominik Brodowski <linux@dominikbrodowski.net> Thanks, Dominik
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@embeddedor.com> > --- > 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!
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,
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@embeddedor.com> --- drivers/cpufreq/speedstep-ich.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)