Re: [PATCH v6] devres: combine function devm_ioremap*

[Yisheng Xie <xieyisheng1@huawei.com>]

Hi Christophe,

On 2018/2/12 19:21, Christophe LEROY wrote:
> Hi Yisheng,
> 
> I don't have any comment.
> 
> Reviewed-by: <christophe.leroy@c-s.fr>

Thanks
Yisheng
> 
> Christophe
> 
> Le 12/02/2018 à 12:07, Yisheng Xie a écrit :
>> Hi Greg, Christophe,
>>
>> Any comment about this version?  And sorry to disturb  :)
>>
>> Thanks
>> Yisheng
>>
>> On 2018/1/29 19:48, Yisheng Xie wrote:
>>> When I tried to use devm_ioremap function and review related
>>> code, I found devm_ioremap_* almost have the similar realize
>>> with each other, which can be combined.
>>>
>>> In the former version, I have tried to kill ioremap_cache to
>>> reduce the size of devres, which can not work for ioremap is
>>> not the same as ioremap_nocache in some ARCHs likes ia64.
>>> Therefore, as the suggestion of Christophe, I introduce a help
>>> function __devm_ioremap, let devm_ioremap* inline and call
>>> __devm_ioremap with different devm_ioremap_type.
>>>
>>> After apply the patch, the size of devres.o can be reduce from
>>> 8216 Bytes to 8052 Bytes in my compile environment.
>>>
>>> Suggested-by: Greg KH <gregkh@linuxfoundation.org>
>>> Suggested-by: Christophe LEROY <christophe.leroy@c-s.fr>
>>> Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com>
>>> ---
>>> v2:
>>>   - use MARCO for ioremap
>>> v3:
>>>   - kill dev_ioremap_nocache
>>> v4:
>>>   - combine function devm_ioremap*       - per Christophe
>>> v5:
>>>   - fix code style.                      - per Christophe
>>> v6:
>>>   - just put the cleanup in the devres.c - per Greg
>>>
>>>   lib/devres.c | 78 +++++++++++++++++++++++++++++-------------------------------
>>>   1 file changed, 38 insertions(+), 40 deletions(-)
>>>
>>> diff --git a/lib/devres.c b/lib/devres.c
>>> index 5f2aedd..5bec112 100644
>>> --- a/lib/devres.c
>>> +++ b/lib/devres.c
>>> @@ -5,6 +5,12 @@
>>>   #include <linux/gfp.h>
>>>   #include <linux/export.h>
>>>   +enum devm_ioremap_type {
>>> +    DEVM_IOREMAP = 0,
>>> +    DEVM_IOREMAP_NC,
>>> +    DEVM_IOREMAP_WC,
>>> +};
>>> +
>>>   void devm_ioremap_release(struct device *dev, void *res)
>>>   {
>>>       iounmap(*(void __iomem **)res);
>>> @@ -15,24 +21,28 @@ static int devm_ioremap_match(struct device *dev, void *res, void *match_data)
>>>       return *(void **)res == match_data;
>>>   }
>>>   -/**
>>> - * devm_ioremap - Managed ioremap()
>>> - * @dev: Generic device to remap IO address for
>>> - * @offset: Resource address to map
>>> - * @size: Size of map
>>> - *
>>> - * Managed ioremap().  Map is automatically unmapped on driver detach.
>>> - */
>>> -void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
>>> -               resource_size_t size)
>>> +static void __iomem *__devm_ioremap(struct device *dev, resource_size_t offset,
>>> +                    resource_size_t size,
>>> +                    enum devm_ioremap_type type)
>>>   {
>>> -    void __iomem **ptr, *addr;
>>> +    void __iomem **ptr, *addr = NULL;
>>>         ptr = devres_alloc(devm_ioremap_release, sizeof(*ptr), GFP_KERNEL);
>>>       if (!ptr)
>>>           return NULL;
>>>   -    addr = ioremap(offset, size);
>>> +    switch (type) {
>>> +    case DEVM_IOREMAP:
>>> +        addr = ioremap(offset, size);
>>> +        break;
>>> +    case DEVM_IOREMAP_NC:
>>> +        addr = ioremap_nocache(offset, size);
>>> +        break;
>>> +    case DEVM_IOREMAP_WC:
>>> +        addr = ioremap_wc(offset, size);
>>> +        break;
>>> +    }
>>> +
>>>       if (addr) {
>>>           *ptr = addr;
>>>           devres_add(dev, ptr);
>>> @@ -41,6 +51,20 @@ void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
>>>         return addr;
>>>   }
>>> +
>>> +/**
>>> + * devm_ioremap - Managed ioremap()
>>> + * @dev: Generic device to remap IO address for
>>> + * @offset: Resource address to map
>>> + * @size: Size of map
>>> + *
>>> + * Managed ioremap().  Map is automatically unmapped on driver detach.
>>> + */
>>> +void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
>>> +               resource_size_t size)
>>> +{
>>> +    return __devm_ioremap(dev, offset, size, DEVM_IOREMAP);
>>> +}
>>>   EXPORT_SYMBOL(devm_ioremap);
>>>     /**
>>> @@ -55,20 +79,7 @@ void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
>>>   void __iomem *devm_ioremap_nocache(struct device *dev, resource_size_t offset,
>>>                      resource_size_t size)
>>>   {
>>> -    void __iomem **ptr, *addr;
>>> -
>>> -    ptr = devres_alloc(devm_ioremap_release, sizeof(*ptr), GFP_KERNEL);
>>> -    if (!ptr)
>>> -        return NULL;
>>> -
>>> -    addr = ioremap_nocache(offset, size);
>>> -    if (addr) {
>>> -        *ptr = addr;
>>> -        devres_add(dev, ptr);
>>> -    } else
>>> -        devres_free(ptr);
>>> -
>>> -    return addr;
>>> +    return __devm_ioremap(dev, offset, size, DEVM_IOREMAP_NC);
>>>   }
>>>   EXPORT_SYMBOL(devm_ioremap_nocache);
>>>   @@ -83,20 +94,7 @@ void __iomem *devm_ioremap_nocache(struct device *dev, resource_size_t offset,
>>>   void __iomem *devm_ioremap_wc(struct device *dev, resource_size_t offset,
>>>                     resource_size_t size)
>>>   {
>>> -    void __iomem **ptr, *addr;
>>> -
>>> -    ptr = devres_alloc(devm_ioremap_release, sizeof(*ptr), GFP_KERNEL);
>>> -    if (!ptr)
>>> -        return NULL;
>>> -
>>> -    addr = ioremap_wc(offset, size);
>>> -    if (addr) {
>>> -        *ptr = addr;
>>> -        devres_add(dev, ptr);
>>> -    } else
>>> -        devres_free(ptr);
>>> -
>>> -    return addr;
>>> +    return __devm_ioremap(dev, offset, size, DEVM_IOREMAP_WC);
>>>   }
>>>   EXPORT_SYMBOL(devm_ioremap_wc);
>>>  
> 
> .
>