diff mbox series

[RFC,01/26] hugetlb: make hstate accessor functions const

Message ID 20220624173656.2033256-2-jthoughton@google.com (mailing list archive)
State New
Headers show
Series hugetlb: Introduce HugeTLB high-granularity mapping | expand

Commit Message

James Houghton June 24, 2022, 5:36 p.m. UTC 
This is just a const-correctness change so that the new hugetlb_pte
changes can be const-correct too.

Acked-by: David Rientjes <rientjes@google.com>

Signed-off-by: James Houghton <jthoughton@google.com>
---
 include/linux/hugetlb.h | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

Comments

Mina Almasry June 24, 2022, 6:43 p.m. UTC | #1 
On Fri, Jun 24, 2022 at 10:37 AM James Houghton <jthoughton@google.com> wrote:
>
> This is just a const-correctness change so that the new hugetlb_pte
> changes can be const-correct too.
>
> Acked-by: David Rientjes <rientjes@google.com>
>

Reviewed-By: Mina Almasry <almasrymina@google.com>

> Signed-off-by: James Houghton <jthoughton@google.com>
> ---
>  include/linux/hugetlb.h | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
> index e4cff27d1198..498a4ae3d462 100644
> --- a/include/linux/hugetlb.h
> +++ b/include/linux/hugetlb.h
> @@ -715,7 +715,7 @@ static inline struct hstate *hstate_vma(struct vm_area_struct *vma)
>         return hstate_file(vma->vm_file);
>  }
>
> -static inline unsigned long huge_page_size(struct hstate *h)
> +static inline unsigned long huge_page_size(const struct hstate *h)
>  {
>         return (unsigned long)PAGE_SIZE << h->order;
>  }
> @@ -729,27 +729,27 @@ static inline unsigned long huge_page_mask(struct hstate *h)
>         return h->mask;
>  }
>
> -static inline unsigned int huge_page_order(struct hstate *h)
> +static inline unsigned int huge_page_order(const struct hstate *h)
>  {
>         return h->order;
>  }
>
> -static inline unsigned huge_page_shift(struct hstate *h)
> +static inline unsigned huge_page_shift(const struct hstate *h)
>  {
>         return h->order + PAGE_SHIFT;
>  }
>
> -static inline bool hstate_is_gigantic(struct hstate *h)
> +static inline bool hstate_is_gigantic(const struct hstate *h)
>  {
>         return huge_page_order(h) >= MAX_ORDER;
>  }
>
> -static inline unsigned int pages_per_huge_page(struct hstate *h)
> +static inline unsigned int pages_per_huge_page(const struct hstate *h)
>  {
>         return 1 << h->order;
>  }
>
> -static inline unsigned int blocks_per_huge_page(struct hstate *h)
> +static inline unsigned int blocks_per_huge_page(const struct hstate *h)
>  {
>         return huge_page_size(h) / 512;
>  }
> --
> 2.37.0.rc0.161.g10f37bed90-goog
>
Manish June 27, 2022, 12:09 p.m. UTC | #2 
On 27/06/22 5:06 pm, manish.mishra wrote:
>
>
> On 24/06/22 11:06 pm, James Houghton wrote:
>> This is just a const-correctness change so that the new hugetlb_pte
>> changes can be const-correct too.
>>
>> Acked-by: David Rientjes<rientjes@google.com>
>>
>> Signed-off-by: James Houghton<jthoughton@google.com>
>> ---
>>   include/linux/hugetlb.h | 12 ++++++------
>>   1 file changed, 6 insertions(+), 6 deletions(-)
>>
>> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
>> index e4cff27d1198..498a4ae3d462 100644
>> --- a/include/linux/hugetlb.h
>> +++ b/include/linux/hugetlb.h
>> @@ -715,7 +715,7 @@ static inline struct hstate *hstate_vma(struct vm_area_struct *vma)
>>   	return hstate_file(vma->vm_file);
>>   }
>>   
>> -static inline unsigned long huge_page_size(struct hstate *h)
>> +static inline unsigned long huge_page_size(const struct hstate *h)
>>   {
>>   	return (unsigned long)PAGE_SIZE << h->order;
>>   }
>> @@ -729,27 +729,27 @@ static inline unsigned long huge_page_mask(struct hstate *h)
>>   	return h->mask;
>>   }
>>   
>> -static inline unsigned int huge_page_order(struct hstate *h)
>> +static inline unsigned int huge_page_order(const struct hstate *h)
>>   {
>>   	return h->order;
>>   }
>>   
>> -static inline unsigned huge_page_shift(struct hstate *h)
>> +static inline unsigned huge_page_shift(const struct hstate *h)
>>   {
>>   	return h->order + PAGE_SHIFT;
>>   }
>>   
>> -static inline bool hstate_is_gigantic(struct hstate *h)
>> +static inline bool hstate_is_gigantic(const struct hstate *h)
>>   {
>>   	return huge_page_order(h) >= MAX_ORDER;
>>   }
>>   
>> -static inline unsigned int pages_per_huge_page(struct hstate *h)
>> +static inline unsigned int pages_per_huge_page(const struct hstate *h)
>>   {
>>   	return 1 << h->order;
>>   }
>>   
>> -static inline unsigned int blocks_per_huge_page(struct hstate *h)
>> +static inline unsigned int blocks_per_huge_page(const struct hstate *h)
>>   {
>>   	return huge_page_size(h) / 512;
>>   }
>
> James, Just wanted to check why you did it selectively only for these functions
>
> why not for something like hstate_index which too i see used in your code.
>
James Houghton June 28, 2022, 5:08 p.m. UTC | #3 
On Mon, Jun 27, 2022 at 5:09 AM manish.mishra <manish.mishra@nutanix.com> wrote:
>
>
> On 27/06/22 5:06 pm, manish.mishra wrote:
>
>
> On 24/06/22 11:06 pm, James Houghton wrote:
>
> This is just a const-correctness change so that the new hugetlb_pte
> changes can be const-correct too.
>
> Acked-by: David Rientjes <rientjes@google.com>
>
> Signed-off-by: James Houghton <jthoughton@google.com>
> ---
>  include/linux/hugetlb.h | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
> index e4cff27d1198..498a4ae3d462 100644
> --- a/include/linux/hugetlb.h
> +++ b/include/linux/hugetlb.h
> @@ -715,7 +715,7 @@ static inline struct hstate *hstate_vma(struct vm_area_struct *vma)
>   return hstate_file(vma->vm_file);
>  }
>
> -static inline unsigned long huge_page_size(struct hstate *h)
> +static inline unsigned long huge_page_size(const struct hstate *h)
>  {
>   return (unsigned long)PAGE_SIZE << h->order;
>  }
> @@ -729,27 +729,27 @@ static inline unsigned long huge_page_mask(struct hstate *h)
>   return h->mask;
>  }
>
> -static inline unsigned int huge_page_order(struct hstate *h)
> +static inline unsigned int huge_page_order(const struct hstate *h)
>  {
>   return h->order;
>  }
>
> -static inline unsigned huge_page_shift(struct hstate *h)
> +static inline unsigned huge_page_shift(const struct hstate *h)
>  {
>   return h->order + PAGE_SHIFT;
>  }
>
> -static inline bool hstate_is_gigantic(struct hstate *h)
> +static inline bool hstate_is_gigantic(const struct hstate *h)
>  {
>   return huge_page_order(h) >= MAX_ORDER;
>  }
>
> -static inline unsigned int pages_per_huge_page(struct hstate *h)
> +static inline unsigned int pages_per_huge_page(const struct hstate *h)
>  {
>   return 1 << h->order;
>  }
>
> -static inline unsigned int blocks_per_huge_page(struct hstate *h)
> +static inline unsigned int blocks_per_huge_page(const struct hstate *h)
>  {
>   return huge_page_size(h) / 512;
>  }
>
> James, Just wanted to check why you did it selectively only for these functions
>
> why not for something like hstate_index which too i see used in your code.

I'll look into which other functions can be made const. We need
huge_page_shift() to take `const struct hstate *h` so that the hstates
can be sorted, and it then followed to make the surrounding, related
functions const as well. I could also just leave it at
huge_page_shift().

The commit message here is wrong -- the hugetlb_pte const-correctness
is a separate issue that doesn't depend the constness of hstates. I'll
fix that -- sorry about that.
Muchun Song June 29, 2022, 6:18 a.m. UTC | #4 
On Fri, Jun 24, 2022 at 05:36:31PM +0000, James Houghton wrote:
> This is just a const-correctness change so that the new hugetlb_pte
> changes can be const-correct too.
> 
> Acked-by: David Rientjes <rientjes@google.com>
> 
> Signed-off-by: James Houghton <jthoughton@google.com>

This is a good start. I also want to make those helpers take
const type parameter. Seems you have forgotten to update them
when !CONFIG_HUGETLB_PAGE.

Thanks.

> ---
>  include/linux/hugetlb.h | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
> index e4cff27d1198..498a4ae3d462 100644
> --- a/include/linux/hugetlb.h
> +++ b/include/linux/hugetlb.h
> @@ -715,7 +715,7 @@ static inline struct hstate *hstate_vma(struct vm_area_struct *vma)
>  	return hstate_file(vma->vm_file);
>  }
>  
> -static inline unsigned long huge_page_size(struct hstate *h)
> +static inline unsigned long huge_page_size(const struct hstate *h)
>  {
>  	return (unsigned long)PAGE_SIZE << h->order;
>  }
> @@ -729,27 +729,27 @@ static inline unsigned long huge_page_mask(struct hstate *h)
>  	return h->mask;
>  }
>  
> -static inline unsigned int huge_page_order(struct hstate *h)
> +static inline unsigned int huge_page_order(const struct hstate *h)
>  {
>  	return h->order;
>  }
>  
> -static inline unsigned huge_page_shift(struct hstate *h)
> +static inline unsigned huge_page_shift(const struct hstate *h)
>  {
>  	return h->order + PAGE_SHIFT;
>  }
>  
> -static inline bool hstate_is_gigantic(struct hstate *h)
> +static inline bool hstate_is_gigantic(const struct hstate *h)
>  {
>  	return huge_page_order(h) >= MAX_ORDER;
>  }
>  
> -static inline unsigned int pages_per_huge_page(struct hstate *h)
> +static inline unsigned int pages_per_huge_page(const struct hstate *h)
>  {
>  	return 1 << h->order;
>  }
>  
> -static inline unsigned int blocks_per_huge_page(struct hstate *h)
> +static inline unsigned int blocks_per_huge_page(const struct hstate *h)
>  {
>  	return huge_page_size(h) / 512;
>  }
> -- 
> 2.37.0.rc0.161.g10f37bed90-goog
> 
>
diff mbox series

Patch

diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index e4cff27d1198..498a4ae3d462 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -715,7 +715,7 @@  static inline struct hstate *hstate_vma(struct vm_area_struct *vma)
 	return hstate_file(vma->vm_file);
 }
 
-static inline unsigned long huge_page_size(struct hstate *h)
+static inline unsigned long huge_page_size(const struct hstate *h)
 {
 	return (unsigned long)PAGE_SIZE << h->order;
 }
@@ -729,27 +729,27 @@  static inline unsigned long huge_page_mask(struct hstate *h)
 	return h->mask;
 }
 
-static inline unsigned int huge_page_order(struct hstate *h)
+static inline unsigned int huge_page_order(const struct hstate *h)
 {
 	return h->order;
 }
 
-static inline unsigned huge_page_shift(struct hstate *h)
+static inline unsigned huge_page_shift(const struct hstate *h)
 {
 	return h->order + PAGE_SHIFT;
 }
 
-static inline bool hstate_is_gigantic(struct hstate *h)
+static inline bool hstate_is_gigantic(const struct hstate *h)
 {
 	return huge_page_order(h) >= MAX_ORDER;
 }
 
-static inline unsigned int pages_per_huge_page(struct hstate *h)
+static inline unsigned int pages_per_huge_page(const struct hstate *h)
 {
 	return 1 << h->order;
 }
 
-static inline unsigned int blocks_per_huge_page(struct hstate *h)
+static inline unsigned int blocks_per_huge_page(const struct hstate *h)
 {
 	return huge_page_size(h) / 512;
 }