2023-07-06 16:41:33

by Sidhartha Kumar

Subject: [PATCH v3 2/4] mm/memory: convert wp_page_shared() to use folios

Saves six implicit calls to compound_head().

Signed-off-by: Sidhartha Kumar <[email protected]>
---
v3:
- remove extra page_folio() by moving up folio initialization
v2:
- change function definition to pass in a folio
mm/memory.c | 22 +++++++++++-----------
1 file changed, 11 insertions(+), 11 deletions(-)

diff --git a/mm/memory.c b/mm/memory.c
index 1736a130fa829..673b9fa67d0d7 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -3285,13 +3285,13 @@ static vm_fault_t wp_pfn_shared(struct vm_fault *vmf)
return 0;
}

-static vm_fault_t wp_page_shared(struct vm_fault *vmf)
+static vm_fault_t wp_page_shared(struct vm_fault *vmf, struct folio *folio)
__releases(vmf->ptl)
{
struct vm_area_struct *vma = vmf->vma;
vm_fault_t ret = 0;

- get_page(vmf->page);
+ folio_get(folio);

if (vma->vm_ops && vma->vm_ops->page_mkwrite) {
vm_fault_t tmp;
@@ -3300,21 +3300,21 @@ static vm_fault_t wp_page_shared(struct vm_fault *vmf)
tmp = do_page_mkwrite(vmf);
if (unlikely(!tmp || (tmp &
(VM_FAULT_ERROR | VM_FAULT_NOPAGE)))) {
- put_page(vmf->page);
+ folio_put(folio);
return tmp;
}
tmp = finish_mkwrite_fault(vmf);
if (unlikely(tmp & (VM_FAULT_ERROR | VM_FAULT_NOPAGE))) {
- unlock_page(vmf->page);
- put_page(vmf->page);
+ folio_unlock(folio);
+ folio_put(folio);
return tmp;
}
} else {
wp_page_reuse(vmf);
- lock_page(vmf->page);
+ folio_lock(folio);
}
ret |= fault_dirty_shared_page(vmf);
- put_page(vmf->page);
+ folio_put(folio);

return ret;
}
@@ -3365,6 +3365,9 @@ static vm_fault_t do_wp_page(struct vm_fault *vmf)

vmf->page = vm_normal_page(vma, vmf->address, vmf->orig_pte);

+ if (vmf->page)
+ folio = page_folio(vmf->page);
+
/*
* Shared mapping: we are guaranteed to have VM_WRITE and
* FAULT_FLAG_WRITE set at this point.
@@ -3379,12 +3382,9 @@ static vm_fault_t do_wp_page(struct vm_fault *vmf)
*/
if (!vmf->page)
return wp_pfn_shared(vmf);
- return wp_page_shared(vmf);
+ return wp_page_shared(vmf, folio);
}

- if (vmf->page)
- folio = page_folio(vmf->page);
-
/*
* Private mapping: create an exclusive anonymous page copy if reuse
* is impossible. We might miss VM_WRITE for FOLL_FORCE handling.
--
2.41.0

2023-07-06 17:58:35

by Matthew Wilcox

Subject: Re: [PATCH v3 2/4] mm/memory: convert wp_page_shared() to use folios

On Thu, Jul 06, 2023 at 09:38:45AM -0700, Sidhartha Kumar wrote:
> Saves six implicit calls to compound_head().
>
> Signed-off-by: Sidhartha Kumar <[email protected]>

Reviewed-by: Matthew Wilcox (Oracle) <[email protected]>

2023-07-06 19:24:50

by Sidhartha Kumar

Subject: Re: [PATCH v3 2/4] mm/memory: convert wp_page_shared() to use folios

On 7/6/23 10:48 AM, Matthew Wilcox wrote:
> On Thu, Jul 06, 2023 at 09:38:45AM -0700, Sidhartha Kumar wrote:
>> Saves six implicit calls to compound_head().
>>
>> Signed-off-by: Sidhartha Kumar <[email protected]>
>
> Reviewed-by: Matthew Wilcox (Oracle) <[email protected]>

Thanks for the review throughout the revisions.

Sidhartha Kumar

2023-07-07 10:44:51

by zhangpeng (AS)

Subject: Re: [PATCH v3 2/4] mm/memory: convert wp_page_shared() to use folios

On 2023/7/7 0:38, Sidhartha Kumar wrote:

> Saves six implicit calls to compound_head().
>
> Signed-off-by: Sidhartha Kumar <[email protected]>

Reviewed-by: ZhangPeng<[email protected]>