Re: [PATCH 1/2] mm/page_alloc.c: cleanup obsolete KM_USER*
Hi David,
First of all, thanks a lot for your time reviewing this series.
On Fri, Apr 24, 2015 at 11:36 PM, David Rientjes wrote:
> On Fri, 24 Apr 2015, Anisse Astier wrote:
>
>> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
>> index ebffa0e..05fcec9 100644
>> --- a/mm/page_alloc.c
>> +++ b/mm/page_alloc.c
>> @@ -380,16 +380,10 @@ void prep_compound_page(struct page *page, unsigned
>> long order)
>> }
>> }
>>
>> -static inline void prep_zero_page(struct page *page, unsigned int order,
>> - gfp_t gfp_flags)
>> +static inline void zero_pages(struct page *page, unsigned int order)
>> {
>> int i;
>>
>> - /*
>> - * clear_highpage() will use KM_USER0, so it's a bug to use __GFP_ZERO
>> - * and __GFP_HIGHMEM from hard or soft interrupt context.
>> - */
>> - VM_BUG_ON((gfp_flags & __GFP_HIGHMEM) && in_interrupt());
>> for (i = 0; i < (1 << order); i++)
>> clear_highpage(page + i);
>> }
>> @@ -975,7 +969,7 @@ static int prep_new_page(struct page *page, unsigned int
>> order, gfp_t gfp_flags,
>> kasan_alloc_pages(page, order);
>>
>> if (gfp_flags & __GFP_ZERO)
>> - prep_zero_page(page, order, gfp_flags);
>> + zero_pages(page, order);
>>
>> if (order && (gfp_flags & __GFP_COMP))
>> prep_compound_page(page, order);
>
> No objection to removing the VM_BUG_ON() here, but I'm not sure that we
> need an inline function to do this and to add additional callers in your
> next patch. Why can't we just remove the helper entirely and do the
> iteration in prep_new_page()? We iterate pages all the time.
I just felt it was easier to read as a whole; unless anyone else
objects, I think I'll keep it as-is in the next iteration.
Anisse
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 1/2] mm/page_alloc.c: cleanup obsolete KM_USER*
Hi David,
First of all, thanks a lot for your time reviewing this series.
On Fri, Apr 24, 2015 at 11:36 PM, David Rientjes rient...@google.com wrote:
On Fri, 24 Apr 2015, Anisse Astier wrote:
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index ebffa0e..05fcec9 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -380,16 +380,10 @@ void prep_compound_page(struct page *page, unsigned
long order)
}
}
-static inline void prep_zero_page(struct page *page, unsigned int order,
- gfp_t gfp_flags)
+static inline void zero_pages(struct page *page, unsigned int order)
{
int i;
- /*
- * clear_highpage() will use KM_USER0, so it's a bug to use __GFP_ZERO
- * and __GFP_HIGHMEM from hard or soft interrupt context.
- */
- VM_BUG_ON((gfp_flags __GFP_HIGHMEM) in_interrupt());
for (i = 0; i (1 order); i++)
clear_highpage(page + i);
}
@@ -975,7 +969,7 @@ static int prep_new_page(struct page *page, unsigned int
order, gfp_t gfp_flags,
kasan_alloc_pages(page, order);
if (gfp_flags __GFP_ZERO)
- prep_zero_page(page, order, gfp_flags);
+ zero_pages(page, order);
if (order (gfp_flags __GFP_COMP))
prep_compound_page(page, order);
No objection to removing the VM_BUG_ON() here, but I'm not sure that we
need an inline function to do this and to add additional callers in your
next patch. Why can't we just remove the helper entirely and do the
iteration in prep_new_page()? We iterate pages all the time.
I just felt it was easier to read as a whole; unless anyone else
objects, I think I'll keep it as-is in the next iteration.
Anisse
--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 1/2] mm/page_alloc.c: cleanup obsolete KM_USER*
On Fri, 24 Apr 2015, Anisse Astier wrote:
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index ebffa0e..05fcec9 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -380,16 +380,10 @@ void prep_compound_page(struct page *page, unsigned
> long order)
> }
> }
>
> -static inline void prep_zero_page(struct page *page, unsigned int order,
> - gfp_t gfp_flags)
> +static inline void zero_pages(struct page *page, unsigned int order)
> {
> int i;
>
> - /*
> - * clear_highpage() will use KM_USER0, so it's a bug to use __GFP_ZERO
> - * and __GFP_HIGHMEM from hard or soft interrupt context.
> - */
> - VM_BUG_ON((gfp_flags & __GFP_HIGHMEM) && in_interrupt());
> for (i = 0; i < (1 << order); i++)
> clear_highpage(page + i);
> }
> @@ -975,7 +969,7 @@ static int prep_new_page(struct page *page, unsigned int
> order, gfp_t gfp_flags,
> kasan_alloc_pages(page, order);
>
> if (gfp_flags & __GFP_ZERO)
> - prep_zero_page(page, order, gfp_flags);
> + zero_pages(page, order);
>
> if (order && (gfp_flags & __GFP_COMP))
> prep_compound_page(page, order);
No objection to removing the VM_BUG_ON() here, but I'm not sure that we
need an inline function to do this and to add additional callers in your
next patch. Why can't we just remove the helper entirely and do the
iteration in prep_new_page()? We iterate pages all the time.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 1/2] mm/page_alloc.c: cleanup obsolete KM_USER*
On Fri, 24 Apr 2015, Anisse Astier wrote:
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index ebffa0e..05fcec9 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -380,16 +380,10 @@ void prep_compound_page(struct page *page, unsigned
long order)
}
}
-static inline void prep_zero_page(struct page *page, unsigned int order,
- gfp_t gfp_flags)
+static inline void zero_pages(struct page *page, unsigned int order)
{
int i;
- /*
- * clear_highpage() will use KM_USER0, so it's a bug to use __GFP_ZERO
- * and __GFP_HIGHMEM from hard or soft interrupt context.
- */
- VM_BUG_ON((gfp_flags __GFP_HIGHMEM) in_interrupt());
for (i = 0; i (1 order); i++)
clear_highpage(page + i);
}
@@ -975,7 +969,7 @@ static int prep_new_page(struct page *page, unsigned int
order, gfp_t gfp_flags,
kasan_alloc_pages(page, order);
if (gfp_flags __GFP_ZERO)
- prep_zero_page(page, order, gfp_flags);
+ zero_pages(page, order);
if (order (gfp_flags __GFP_COMP))
prep_compound_page(page, order);
No objection to removing the VM_BUG_ON() here, but I'm not sure that we
need an inline function to do this and to add additional callers in your
next patch. Why can't we just remove the helper entirely and do the
iteration in prep_new_page()? We iterate pages all the time.
--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
