[PATCH 0/9] Drop unnecessary static

[PATCH 0/9] Drop unnecessary static

[Julia Lawall]

These patches fix cases where there is a static on a local variable, but
the variable is either first initialized or never used, on every possible
execution path through the function.  The static has no benefit, and
dropping it reduces the code size.

---

 drivers/block/drbd/drbd_nl.c            |    2 +-
 drivers/clocksource/timer-fttmr010.c    |    2 +-
 drivers/iio/accel/hid-sensor-accel-3d.c |    2 +-
 drivers/mfd/max8925-i2c.c               |    2 +-
 drivers/mfd/twl4030-irq.c               |    2 +-
 drivers/mtd/chips/cfi_cmdset_0020.c     |    2 +-
 drivers/mtd/maps/physmap_of_gemini.c    |    2 +-
 drivers/power/supply/axp20x_usb_power.c |    2 +-
 drivers/regulator/palmas-regulator.c    |    2 +-
 9 files changed, 9 insertions(+), 9 deletions(-)

______________________________________________________
Linux MTD discussion mailing list
http://lists.infradead.org/mailman/listinfo/linux-mtd/

[PATCH 5/9] mfd: Drop unnecessary static

[Julia Lawall]

Drop static on a local variable, when the variable is initialized before
any use, on every possible execution path through the function.

The semantic patch that fixes this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@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;
// </smpl>

The change increases the code size but decreases the size of the bss segment.

before:
   text    data     bss     dec     hex filename
   3369     272     300    3941     f65 drivers/mfd/twl4030-irq.o

after:
   text    data     bss     dec     hex filename
   3401     272      28    3701     e75 drivers/mfd/twl4030-irq.o

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/mfd/twl4030-irq.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mfd/twl4030-irq.c b/drivers/mfd/twl4030-irq.c
index b46c0cf..c775f27 100644
--- a/drivers/mfd/twl4030-irq.c
+++ b/drivers/mfd/twl4030-irq.c
@@ -683,7 +683,7 @@ int twl4030_sih_setup(struct device *dev, int module, int irq_base)
 
 int twl4030_init_irq(struct device *dev, int irq_num)
 {
-	static struct irq_chip	twl4030_irq_chip;
+	struct irq_chip	twl4030_irq_chip;
 	int			status, i;
 	int			irq_base, irq_end, nr_irqs;
 	struct			device_node *node = dev->of_node;

[PATCH 6/9] regulator: palmas: Drop unnecessary static

[Julia Lawall]

Drop static on a local variable, when the variable is initialized before
any use, on every possible execution path through the function.

The semantic patch that fixes this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@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;
// </smpl>

There is no reduction in code size in this case, but the change does reduce
the size of the bss segment, containing uninitialized static data.

before:
   text    data     bss     dec     hex filename
  12882    3480       8   16370    3ff2 drivers/regulator/palmas-regulator.o

after:
   text    data     bss     dec     hex filename
  12882    3480       0   16362    3fea drivers/regulator/palmas-regulator.o

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/regulator/palmas-regulator.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/regulator/palmas-regulator.c b/drivers/regulator/palmas-regulator.c
index 31ae5ee..34d4a62 100644
--- a/drivers/regulator/palmas-regulator.c
+++ b/drivers/regulator/palmas-regulator.c
@@ -1491,7 +1491,7 @@ static int palmas_dt_to_pdata(struct device *dev,
 	}
 
 	for (idx = 0; idx < ddata->max_reg; idx++) {
-		static struct of_regulator_match *match;
+		struct of_regulator_match *match;
 		struct palmas_reg_init *rinit;
 		struct device_node *np;
 

Re: [PATCH 6/9] regulator: palmas: Drop unnecessary static

[Mark Brown]

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On Thu, May 04, 2017 at 10:10:51PM +0200, Julia Lawall wrote:
> Drop static on a local variable, when the variable is initialized before
> any use, on every possible execution path through the function.

When sending a bunch of changes like this please either send the cover
letter to everyone or send each patch separately (this seems like it
stands alone just fine).  The first question when only one patch in a
series is visible is always what are the interdependencies.

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Re: [PATCH 6/9] regulator: palmas: Drop unnecessary static

[Julia Lawall]

On Sun, 14 May 2017, Mark Brown wrote:

> On Thu, May 04, 2017 at 10:10:51PM +0200, Julia Lawall wrote:
> > Drop static on a local variable, when the variable is initialized before
> > any use, on every possible execution path through the function.
>
> When sending a bunch of changes like this please either send the cover
> letter to everyone or send each patch separately (this seems like it
> stands alone just fine).  The first question when only one patch in a
> series is visible is always what are the interdependencies.

Not sure what is best to do.  If the cover letter goes to everyone, it
could be rejected for too many recipients.  Currently it goes to all the
mailing lists.  If the patches are sent separately, then could there be a
cover letter for each one?  If the semantic patch is complicated, then I
typically put the whole thing there, and an abbreviated one in the actual
patch.  That is not relevant here, because the semantic patch is small.
Part of the purpose of the cover letter was to allow people who were not
interested to skip over the whole thing at once.

julia

Re: [PATCH 6/9] regulator: palmas: Drop unnecessary static

[Mark Brown]

[-- Attachment #1: Type: text/plain, Size: 663 bytes --]

On Mon, May 15, 2017 at 06:41:41PM +0800, Julia Lawall wrote:

> mailing lists.  If the patches are sent separately, then could there be a
> cover letter for each one?  If the semantic patch is complicated, then I
> typically put the whole thing there, and an abbreviated one in the actual
> patch.  That is not relevant here, because the semantic patch is small.

Well, if the cover letter is needed to understand the patch then it
needs to go to everyone anyway...

> Part of the purpose of the cover letter was to allow people who were not
> interested to skip over the whole thing at once.

On the flip side things that lack context can get discarded easily.

[-- Attachment #2: signature.asc --]
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Applied "regulator: palmas: Drop unnecessary static" to the regulator tree

[Mark Brown]

The patch

   regulator: palmas: Drop unnecessary static

has been applied to the regulator tree at

   git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator.git 

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.  

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

>From 96e4f5232c8cdb64cb18721ea0871c849346cbf5 Mon Sep 17 00:00:00 2001
From: Julia Lawall <Julia.Lawall@lip6.fr>
Date: Thu, 4 May 2017 22:10:51 +0200
Subject: [PATCH] regulator: palmas: Drop unnecessary static

Drop static on a local variable, when the variable is initialized before
any use, on every possible execution path through the function.

The semantic patch that fixes this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@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;
// </smpl>

There is no reduction in code size in this case, but the change does reduce
the size of the bss segment, containing uninitialized static data.

before:
   text    data     bss     dec     hex filename
  12882    3480       8   16370    3ff2 drivers/regulator/palmas-regulator.o

after:
   text    data     bss     dec     hex filename
  12882    3480       0   16362    3fea drivers/regulator/palmas-regulator.o

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 drivers/regulator/palmas-regulator.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/regulator/palmas-regulator.c b/drivers/regulator/palmas-regulator.c
index 31ae5ee3a80d..34d4a62283d7 100644
--- a/drivers/regulator/palmas-regulator.c
+++ b/drivers/regulator/palmas-regulator.c
@@ -1491,7 +1491,7 @@ static int palmas_dt_to_pdata(struct device *dev,
 	}
 
 	for (idx = 0; idx < ddata->max_reg; idx++) {
-		static struct of_regulator_match *match;
+		struct of_regulator_match *match;
 		struct palmas_reg_init *rinit;
 		struct device_node *np;
 
-- 
2.11.0

Re: [PATCH 5/9] mfd: Drop unnecessary static

[Kees Cook]

On Thu, May 4, 2017 at 1:10 PM, Julia Lawall <Julia.Lawall@lip6.fr> wrote:
> Drop static on a local variable, when the variable is initialized before
> any use, on every possible execution path through the function.
>
> The semantic patch that fixes this problem is as follows:
> (http://coccinelle.lip6.fr/)
>
> // <smpl>
> @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;
> // </smpl>
>
> The change increases the code size but decreases the size of the bss segment.
>
> before:
>    text    data     bss     dec     hex filename
>    3369     272     300    3941     f65 drivers/mfd/twl4030-irq.o
>
> after:
>    text    data     bss     dec     hex filename
>    3401     272      28    3701     e75 drivers/mfd/twl4030-irq.o
>
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
>
> ---
>  drivers/mfd/twl4030-irq.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/mfd/twl4030-irq.c b/drivers/mfd/twl4030-irq.c
> index b46c0cf..c775f27 100644
> --- a/drivers/mfd/twl4030-irq.c
> +++ b/drivers/mfd/twl4030-irq.c
> @@ -683,7 +683,7 @@ int twl4030_sih_setup(struct device *dev, int module, int irq_base)
>
>  int twl4030_init_irq(struct device *dev, int irq_num)
>  {
> -       static struct irq_chip  twl4030_irq_chip;
> +       struct irq_chip twl4030_irq_chip;
>         int                     status, i;
>         int                     irq_base, irq_end, nr_irqs;
>         struct                  device_node *node = dev->of_node;
>

Acked-by: Kees Cook <keescook@chromium.org>

Kernel janitors or Andrew, can you pick this up?

Thanks!

-- 
Kees Cook
Pixel Security

Re: [PATCH 0/9] Drop unnecessary static

[Kees Cook]

On Thu, May 4, 2017 at 1:10 PM, Julia Lawall <Julia.Lawall@lip6.fr> wrote:
> These patches fix cases where there is a static on a local variable, but
> the variable is either first initialized or never used, on every possible
> execution path through the function.  The static has no benefit, and
> dropping it reduces the code size.
>
> ---
>
>  drivers/block/drbd/drbd_nl.c            |    2 +-
>  drivers/clocksource/timer-fttmr010.c    |    2 +-
>  drivers/iio/accel/hid-sensor-accel-3d.c |    2 +-
>  drivers/mfd/max8925-i2c.c               |    2 +-
>  drivers/mfd/twl4030-irq.c               |    2 +-
>  drivers/mtd/chips/cfi_cmdset_0020.c     |    2 +-
>  drivers/mtd/maps/physmap_of_gemini.c    |    2 +-
>  drivers/power/supply/axp20x_usb_power.c |    2 +-
>  drivers/regulator/palmas-regulator.c    |    2 +-
>  9 files changed, 9 insertions(+), 9 deletions(-)

It looks like most of these were taken. I pinged the other three. Thanks!

-Kees

-- 
Kees Cook
Pixel Security

Re: [PATCH 5/9] mfd: Drop unnecessary static

[Lee Jones]

On Tue, 27 Jun 2017, Kees Cook wrote:

> On Thu, May 4, 2017 at 1:10 PM, Julia Lawall <Julia.Lawall@lip6.fr> wrote:
> > Drop static on a local variable, when the variable is initialized before
> > any use, on every possible execution path through the function.
> >
> > The semantic patch that fixes this problem is as follows:
> > (http://coccinelle.lip6.fr/)
> >
> > // <smpl>
> > @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;
> > // </smpl>
> >
> > The change increases the code size but decreases the size of the bss segment.
> >
> > before:
> >    text    data     bss     dec     hex filename
> >    3369     272     300    3941     f65 drivers/mfd/twl4030-irq.o
> >
> > after:
> >    text    data     bss     dec     hex filename
> >    3401     272      28    3701     e75 drivers/mfd/twl4030-irq.o
> >
> > Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
> >
> > ---
> >  drivers/mfd/twl4030-irq.c |    2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/mfd/twl4030-irq.c b/drivers/mfd/twl4030-irq.c
> > index b46c0cf..c775f27 100644
> > --- a/drivers/mfd/twl4030-irq.c
> > +++ b/drivers/mfd/twl4030-irq.c
> > @@ -683,7 +683,7 @@ int twl4030_sih_setup(struct device *dev, int module, int irq_base)
> >
> >  int twl4030_init_irq(struct device *dev, int irq_num)
> >  {
> > -       static struct irq_chip  twl4030_irq_chip;
> > +       struct irq_chip twl4030_irq_chip;
> >         int                     status, i;
> >         int                     irq_base, irq_end, nr_irqs;
> >         struct                  device_node *node = dev->of_node;
> >
> 
> Acked-by: Kees Cook <keescook@chromium.org>
> 
> Kernel janitors or Andrew, can you pick this up?

Same.

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

Re: [PATCH 5/9] mfd: Drop unnecessary static

[Lee Jones]

On Thu, 04 May 2017, Julia Lawall wrote:

> Drop static on a local variable, when the variable is initialized before
> any use, on every possible execution path through the function.
> 
> The semantic patch that fixes this problem is as follows:
> (http://coccinelle.lip6.fr/)
> 
> // <smpl>
> @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;
> // </smpl>
> 
> The change increases the code size but decreases the size of the bss segment.
> 
> before:
>    text    data     bss     dec     hex filename
>    3369     272     300    3941     f65 drivers/mfd/twl4030-irq.o
> 
> after:
>    text    data     bss     dec     hex filename
>    3401     272      28    3701     e75 drivers/mfd/twl4030-irq.o
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
> 
> ---
>  drivers/mfd/twl4030-irq.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Applied, thanks.

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog