lkml.org 
[lkml]   [2017]   [Jul]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] pinctrl: st: constify gpio_chip structure
Hi Patrice,

Quoting Patrice CHOTARD <patrice.chotard@st.com>:

> Hi Gustavo
>
> On 07/11/2017 08:15 PM, Gustavo A. R. Silva wrote:
>> This structure is only used to copy into other structure, so declare
>> it as const.
>>
>> This issue was detected using Coccinelle and the following semantic patch:
>>
>> @r disable optional_qualifier@
>> identifier i;
>> position p;
>> @@
>> static struct gpio_chip i@p = { ... };
>>
>> @ok@
>> identifier r.i;
>> expression e;
>> position p;
>> @@
>> e = i@p;
>>
>> @bad@
>> position p != {r.p,ok.p};
>> identifier r.i;
>> struct gpio_chip e;
>> @@
>> e@i@p
>>
>> @depends on !bad disable optional_qualifier@
>> identifier r.i;
>> @@
>> static
>> +const
>> struct gpio_chip i = { ... };
>>
>> In the following log you can see a significant difference in the code size
>> and data segment, hence in the dec segment. This log is the output
>> of the size command, before and after the code change:
>>
>> before:
>> text data bss dec hex filename
>> 21671 3632 128 25431 6357 drivers/pinctrl/pinctrl-st.o
>>
>> after:
>> text data bss dec hex filename
>> 21366 3576 128 25070 61ee drivers/pinctrl/pinctrl-st.o
>>
>> Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
>> ---
>> drivers/pinctrl/pinctrl-st.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/pinctrl/pinctrl-st.c b/drivers/pinctrl/pinctrl-st.c
>> index 3ae8066..5d4789d 100644
>> --- a/drivers/pinctrl/pinctrl-st.c
>> +++ b/drivers/pinctrl/pinctrl-st.c
>> @@ -1442,7 +1442,7 @@ static void st_gpio_irqmux_handler(struct
>> irq_desc *desc)
>> chained_irq_exit(chip, desc);
>> }
>>
>> -static struct gpio_chip st_gpio_template = {
>> +static const struct gpio_chip st_gpio_template = {
>> .request = gpiochip_generic_request,
>> .free = gpiochip_generic_free,
>> .get = st_gpio_get,
>>
>
> Acked-by: Patrice Chotard <patrice.chotard@st.com>
>
> Thanks

Glad to help. :)

Thanks
--
Gustavo A. R. Silva





\
 
 \ /
  Last update: 2017-07-12 18:52    [W:0.250 / U:0.192 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site