2016-04-20 18:50:51

by Shi, Yang

[permalink] [raw]
Subject: [PATCH] mm: move huge_pmd_set_accessed out of huge_memory.c

huge_pmd_set_accessed is only called by __handle_mm_fault from memory.c,
move the definition to memory.c and make it static like create_huge_pmd and
wp_huge_pmd.

Signed-off-by: Yang Shi <[email protected]>
---
include/linux/huge_mm.h | 4 ----
mm/huge_memory.c | 23 -----------------------
mm/memory.c | 23 +++++++++++++++++++++++
3 files changed, 23 insertions(+), 27 deletions(-)

diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
index 7008623..c218ab7b 100644
--- a/include/linux/huge_mm.h
+++ b/include/linux/huge_mm.h
@@ -8,10 +8,6 @@ extern int do_huge_pmd_anonymous_page(struct mm_struct *mm,
extern int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
pmd_t *dst_pmd, pmd_t *src_pmd, unsigned long addr,
struct vm_area_struct *vma);
-extern void huge_pmd_set_accessed(struct mm_struct *mm,
- struct vm_area_struct *vma,
- unsigned long address, pmd_t *pmd,
- pmd_t orig_pmd, int dirty);
extern int do_huge_pmd_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long address, pmd_t *pmd,
pmd_t orig_pmd);
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index fecbbc5..6c14cb6 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1137,29 +1137,6 @@ out:
return ret;
}

-void huge_pmd_set_accessed(struct mm_struct *mm,
- struct vm_area_struct *vma,
- unsigned long address,
- pmd_t *pmd, pmd_t orig_pmd,
- int dirty)
-{
- spinlock_t *ptl;
- pmd_t entry;
- unsigned long haddr;
-
- ptl = pmd_lock(mm, pmd);
- if (unlikely(!pmd_same(*pmd, orig_pmd)))
- goto unlock;
-
- entry = pmd_mkyoung(orig_pmd);
- haddr = address & HPAGE_PMD_MASK;
- if (pmdp_set_access_flags(vma, haddr, pmd, entry, dirty))
- update_mmu_cache_pmd(vma, address, pmd);
-
-unlock:
- spin_unlock(ptl);
-}
-
static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm,
struct vm_area_struct *vma,
unsigned long address,
diff --git a/mm/memory.c b/mm/memory.c
index 93897f2..6ced4eb 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -3287,6 +3287,29 @@ static int wp_huge_pmd(struct mm_struct *mm, struct vm_area_struct *vma,
return VM_FAULT_FALLBACK;
}

+static void huge_pmd_set_accessed(struct mm_struct *mm,
+ struct vm_area_struct *vma,
+ unsigned long address,
+ pmd_t *pmd, pmd_t orig_pmd,
+ int dirty)
+{
+ spinlock_t *ptl;
+ pmd_t entry;
+ unsigned long haddr;
+
+ ptl = pmd_lock(mm, pmd);
+ if (unlikely(!pmd_same(*pmd, orig_pmd)))
+ goto unlock;
+
+ entry = pmd_mkyoung(orig_pmd);
+ haddr = address & HPAGE_PMD_MASK;
+ if (pmdp_set_access_flags(vma, haddr, pmd, entry, dirty))
+ update_mmu_cache_pmd(vma, address, pmd);
+
+unlock:
+ spin_unlock(ptl);
+}
+
/*
* These routines also need to handle stuff like marking pages dirty
* and/or accessed for architectures that don't do it in hardware (most
--
2.0.2


2016-04-20 19:05:40

by kernel test robot

[permalink] [raw]
Subject: Re: [PATCH] mm: move huge_pmd_set_accessed out of huge_memory.c

Hi,

[auto build test ERROR on v4.6-rc4]
[also build test ERROR on next-20160420]
[if your patch is applied to the wrong git tree, please drop us a note to help improving the system]

url: https://github.com/0day-ci/linux/commits/Yang-Shi/mm-move-huge_pmd_set_accessed-out-of-huge_memory-c/20160421-025318
config: mips-allyesconfig (attached as .config)
reproduce:
wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
make.cross ARCH=mips

All errors (new ones prefixed by >>):

mm/memory.c: In function 'huge_pmd_set_accessed':
>> mm/memory.c:3304:10: error: implicit declaration of function 'pmd_mkyoung' [-Werror=implicit-function-declaration]
entry = pmd_mkyoung(orig_pmd);
^
>> mm/memory.c:3304:8: error: incompatible types when assigning to type 'pmd_t {aka struct <anonymous>}' from type 'int'
entry = pmd_mkyoung(orig_pmd);
^
cc1: some warnings being treated as errors

vim +/pmd_mkyoung +3304 mm/memory.c

3298 unsigned long haddr;
3299
3300 ptl = pmd_lock(mm, pmd);
3301 if (unlikely(!pmd_same(*pmd, orig_pmd)))
3302 goto unlock;
3303
> 3304 entry = pmd_mkyoung(orig_pmd);
3305 haddr = address & HPAGE_PMD_MASK;
3306 if (pmdp_set_access_flags(vma, haddr, pmd, entry, dirty))
3307 update_mmu_cache_pmd(vma, address, pmd);

---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation


Attachments:
(No filename) (1.59 kB)
.config.gz (40.46 kB)
Download all attachments

2016-04-20 19:11:14

by kernel test robot

[permalink] [raw]
Subject: Re: [PATCH] mm: move huge_pmd_set_accessed out of huge_memory.c

Hi,

[auto build test ERROR on v4.6-rc4]
[also build test ERROR on next-20160420]
[if your patch is applied to the wrong git tree, please drop us a note to help improving the system]

url: https://github.com/0day-ci/linux/commits/Yang-Shi/mm-move-huge_pmd_set_accessed-out-of-huge_memory-c/20160421-025318
config: powerpc-allyesconfig (attached as .config)
reproduce:
wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
make.cross ARCH=powerpc

All errors (new ones prefixed by >>):

mm/memory.c: In function 'huge_pmd_set_accessed':
>> mm/memory.c:3307:3: error: implicit declaration of function 'update_mmu_cache_pmd' [-Werror=implicit-function-declaration]
update_mmu_cache_pmd(vma, address, pmd);
^
cc1: some warnings being treated as errors

vim +/update_mmu_cache_pmd +3307 mm/memory.c

3301 if (unlikely(!pmd_same(*pmd, orig_pmd)))
3302 goto unlock;
3303
3304 entry = pmd_mkyoung(orig_pmd);
3305 haddr = address & HPAGE_PMD_MASK;
3306 if (pmdp_set_access_flags(vma, haddr, pmd, entry, dirty))
> 3307 update_mmu_cache_pmd(vma, address, pmd);
3308
3309 unlock:
3310 spin_unlock(ptl);

---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation


Attachments:
(No filename) (1.43 kB)
.config.gz (47.52 kB)
Download all attachments

2016-04-20 19:21:44

by kernel test robot

[permalink] [raw]
Subject: Re: [PATCH] mm: move huge_pmd_set_accessed out of huge_memory.c

Hi,

[auto build test ERROR on v4.6-rc4]
[also build test ERROR on next-20160420]
[if your patch is applied to the wrong git tree, please drop us a note to help improving the system]

url: https://github.com/0day-ci/linux/commits/Yang-Shi/mm-move-huge_pmd_set_accessed-out-of-huge_memory-c/20160421-025318
config: avr32-atngw100_defconfig (attached as .config)
reproduce:
wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
make.cross ARCH=avr32

All errors (new ones prefixed by >>):

mm/memory.c: In function 'huge_pmd_set_accessed':
mm/memory.c:3304: error: implicit declaration of function 'pmd_mkyoung'
>> mm/memory.c:3304: error: incompatible types in assignment
mm/memory.c:3307: error: implicit declaration of function 'update_mmu_cache_pmd'

vim +3304 mm/memory.c

3298 unsigned long haddr;
3299
3300 ptl = pmd_lock(mm, pmd);
3301 if (unlikely(!pmd_same(*pmd, orig_pmd)))
3302 goto unlock;
3303
> 3304 entry = pmd_mkyoung(orig_pmd);
3305 haddr = address & HPAGE_PMD_MASK;
3306 if (pmdp_set_access_flags(vma, haddr, pmd, entry, dirty))
3307 update_mmu_cache_pmd(vma, address, pmd);

---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation


Attachments:
(No filename) (1.42 kB)
.config.gz (12.07 kB)
Download all attachments

2016-04-20 21:00:16

by Shi, Yang

[permalink] [raw]
Subject: Re: [PATCH] mm: move huge_pmd_set_accessed out of huge_memory.c

Hi folks,

I didn't realize pmd_* functions are protected by
CONFIG_TRANSPARENT_HUGEPAGE on the most architectures before I made this
change.

Before I fix all the affected architectures code, I want to check if you
guys think this change is worth or not?

Thanks,
Yang

On 4/20/2016 11:24 AM, Yang Shi wrote:
> huge_pmd_set_accessed is only called by __handle_mm_fault from memory.c,
> move the definition to memory.c and make it static like create_huge_pmd and
> wp_huge_pmd.
>
> Signed-off-by: Yang Shi <[email protected]>
> ---
> include/linux/huge_mm.h | 4 ----
> mm/huge_memory.c | 23 -----------------------
> mm/memory.c | 23 +++++++++++++++++++++++
> 3 files changed, 23 insertions(+), 27 deletions(-)
>
> diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
> index 7008623..c218ab7b 100644
> --- a/include/linux/huge_mm.h
> +++ b/include/linux/huge_mm.h
> @@ -8,10 +8,6 @@ extern int do_huge_pmd_anonymous_page(struct mm_struct *mm,
> extern int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
> pmd_t *dst_pmd, pmd_t *src_pmd, unsigned long addr,
> struct vm_area_struct *vma);
> -extern void huge_pmd_set_accessed(struct mm_struct *mm,
> - struct vm_area_struct *vma,
> - unsigned long address, pmd_t *pmd,
> - pmd_t orig_pmd, int dirty);
> extern int do_huge_pmd_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
> unsigned long address, pmd_t *pmd,
> pmd_t orig_pmd);
> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> index fecbbc5..6c14cb6 100644
> --- a/mm/huge_memory.c
> +++ b/mm/huge_memory.c
> @@ -1137,29 +1137,6 @@ out:
> return ret;
> }
>
> -void huge_pmd_set_accessed(struct mm_struct *mm,
> - struct vm_area_struct *vma,
> - unsigned long address,
> - pmd_t *pmd, pmd_t orig_pmd,
> - int dirty)
> -{
> - spinlock_t *ptl;
> - pmd_t entry;
> - unsigned long haddr;
> -
> - ptl = pmd_lock(mm, pmd);
> - if (unlikely(!pmd_same(*pmd, orig_pmd)))
> - goto unlock;
> -
> - entry = pmd_mkyoung(orig_pmd);
> - haddr = address & HPAGE_PMD_MASK;
> - if (pmdp_set_access_flags(vma, haddr, pmd, entry, dirty))
> - update_mmu_cache_pmd(vma, address, pmd);
> -
> -unlock:
> - spin_unlock(ptl);
> -}
> -
> static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm,
> struct vm_area_struct *vma,
> unsigned long address,
> diff --git a/mm/memory.c b/mm/memory.c
> index 93897f2..6ced4eb 100644
> --- a/mm/memory.c
> +++ b/mm/memory.c
> @@ -3287,6 +3287,29 @@ static int wp_huge_pmd(struct mm_struct *mm, struct vm_area_struct *vma,
> return VM_FAULT_FALLBACK;
> }
>
> +static void huge_pmd_set_accessed(struct mm_struct *mm,
> + struct vm_area_struct *vma,
> + unsigned long address,
> + pmd_t *pmd, pmd_t orig_pmd,
> + int dirty)
> +{
> + spinlock_t *ptl;
> + pmd_t entry;
> + unsigned long haddr;
> +
> + ptl = pmd_lock(mm, pmd);
> + if (unlikely(!pmd_same(*pmd, orig_pmd)))
> + goto unlock;
> +
> + entry = pmd_mkyoung(orig_pmd);
> + haddr = address & HPAGE_PMD_MASK;
> + if (pmdp_set_access_flags(vma, haddr, pmd, entry, dirty))
> + update_mmu_cache_pmd(vma, address, pmd);
> +
> +unlock:
> + spin_unlock(ptl);
> +}
> +
> /*
> * These routines also need to handle stuff like marking pages dirty
> * and/or accessed for architectures that don't do it in hardware (most
>

2016-04-21 07:31:00

by Kirill A. Shutemov

[permalink] [raw]
Subject: Re: [PATCH] mm: move huge_pmd_set_accessed out of huge_memory.c

On Wed, Apr 20, 2016 at 02:00:11PM -0700, Shi, Yang wrote:
> Hi folks,
>
> I didn't realize pmd_* functions are protected by
> CONFIG_TRANSPARENT_HUGEPAGE on the most architectures before I made this
> change.
>
> Before I fix all the affected architectures code, I want to check if you
> guys think this change is worth or not?
>
> Thanks,
> Yang
>
> On 4/20/2016 11:24 AM, Yang Shi wrote:
> >huge_pmd_set_accessed is only called by __handle_mm_fault from memory.c,
> >move the definition to memory.c and make it static like create_huge_pmd and
> >wp_huge_pmd.
> >
> >Signed-off-by: Yang Shi <[email protected]>

On pte side we have the same functionality open-coded. Should we do the
same for pmd? Or change pte side the same way?

--
Kirill A. Shutemov

2016-04-21 09:15:24

by Hugh Dickins

[permalink] [raw]
Subject: Re: [PATCH] mm: move huge_pmd_set_accessed out of huge_memory.c

On Wed, 20 Apr 2016, Shi, Yang wrote:

> Hi folks,
>
> I didn't realize pmd_* functions are protected by CONFIG_TRANSPARENT_HUGEPAGE
> on the most architectures before I made this change.
>
> Before I fix all the affected architectures code, I want to check if you guys
> think this change is worth or not?

Thanks for asking: no, it is not worthwhile.

I would much prefer not to have to consider these trivial cleanups
in the huge memory area at this time. Kirill and I have urgent work
to do in this area, and coping with patch conflicts between different
versions of the source will not help any of us.

Thanks,
Hugh

>
> Thanks,
> Yang
>
> On 4/20/2016 11:24 AM, Yang Shi wrote:
> > huge_pmd_set_accessed is only called by __handle_mm_fault from memory.c,
> > move the definition to memory.c and make it static like create_huge_pmd and
> > wp_huge_pmd.
> >
> > Signed-off-by: Yang Shi <[email protected]>
> > ---
> > include/linux/huge_mm.h | 4 ----
> > mm/huge_memory.c | 23 -----------------------
> > mm/memory.c | 23 +++++++++++++++++++++++
> > 3 files changed, 23 insertions(+), 27 deletions(-)
> >
> > diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
> > index 7008623..c218ab7b 100644
> > --- a/include/linux/huge_mm.h
> > +++ b/include/linux/huge_mm.h
> > @@ -8,10 +8,6 @@ extern int do_huge_pmd_anonymous_page(struct mm_struct
> > *mm,
> > extern int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct
> > *src_mm,
> > pmd_t *dst_pmd, pmd_t *src_pmd, unsigned long addr,
> > struct vm_area_struct *vma);
> > -extern void huge_pmd_set_accessed(struct mm_struct *mm,
> > - struct vm_area_struct *vma,
> > - unsigned long address, pmd_t *pmd,
> > - pmd_t orig_pmd, int dirty);
> > extern int do_huge_pmd_wp_page(struct mm_struct *mm, struct
> > vm_area_struct *vma,
> > unsigned long address, pmd_t *pmd,
> > pmd_t orig_pmd);
> > diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> > index fecbbc5..6c14cb6 100644
> > --- a/mm/huge_memory.c
> > +++ b/mm/huge_memory.c
> > @@ -1137,29 +1137,6 @@ out:
> > return ret;
> > }
> >
> > -void huge_pmd_set_accessed(struct mm_struct *mm,
> > - struct vm_area_struct *vma,
> > - unsigned long address,
> > - pmd_t *pmd, pmd_t orig_pmd,
> > - int dirty)
> > -{
> > - spinlock_t *ptl;
> > - pmd_t entry;
> > - unsigned long haddr;
> > -
> > - ptl = pmd_lock(mm, pmd);
> > - if (unlikely(!pmd_same(*pmd, orig_pmd)))
> > - goto unlock;
> > -
> > - entry = pmd_mkyoung(orig_pmd);
> > - haddr = address & HPAGE_PMD_MASK;
> > - if (pmdp_set_access_flags(vma, haddr, pmd, entry, dirty))
> > - update_mmu_cache_pmd(vma, address, pmd);
> > -
> > -unlock:
> > - spin_unlock(ptl);
> > -}
> > -
> > static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm,
> > struct vm_area_struct *vma,
> > unsigned long address,
> > diff --git a/mm/memory.c b/mm/memory.c
> > index 93897f2..6ced4eb 100644
> > --- a/mm/memory.c
> > +++ b/mm/memory.c
> > @@ -3287,6 +3287,29 @@ static int wp_huge_pmd(struct mm_struct *mm, struct
> > vm_area_struct *vma,
> > return VM_FAULT_FALLBACK;
> > }
> >
> > +static void huge_pmd_set_accessed(struct mm_struct *mm,
> > + struct vm_area_struct *vma,
> > + unsigned long address,
> > + pmd_t *pmd, pmd_t orig_pmd,
> > + int dirty)
> > +{
> > + spinlock_t *ptl;
> > + pmd_t entry;
> > + unsigned long haddr;
> > +
> > + ptl = pmd_lock(mm, pmd);
> > + if (unlikely(!pmd_same(*pmd, orig_pmd)))
> > + goto unlock;
> > +
> > + entry = pmd_mkyoung(orig_pmd);
> > + haddr = address & HPAGE_PMD_MASK;
> > + if (pmdp_set_access_flags(vma, haddr, pmd, entry, dirty))
> > + update_mmu_cache_pmd(vma, address, pmd);
> > +
> > +unlock:
> > + spin_unlock(ptl);
> > +}
> > +
> > /*
> > * These routines also need to handle stuff like marking pages dirty
> > * and/or accessed for architectures that don't do it in hardware (most

2016-04-21 22:56:14

by Shi, Yang

[permalink] [raw]
Subject: Re: [PATCH] mm: move huge_pmd_set_accessed out of huge_memory.c

On 4/21/2016 12:30 AM, Kirill A. Shutemov wrote:
> On Wed, Apr 20, 2016 at 02:00:11PM -0700, Shi, Yang wrote:
>> Hi folks,
>>
>> I didn't realize pmd_* functions are protected by
>> CONFIG_TRANSPARENT_HUGEPAGE on the most architectures before I made this
>> change.
>>
>> Before I fix all the affected architectures code, I want to check if you
>> guys think this change is worth or not?
>>
>> Thanks,
>> Yang
>>
>> On 4/20/2016 11:24 AM, Yang Shi wrote:
>>> huge_pmd_set_accessed is only called by __handle_mm_fault from memory.c,
>>> move the definition to memory.c and make it static like create_huge_pmd and
>>> wp_huge_pmd.
>>>
>>> Signed-off-by: Yang Shi <[email protected]>
>
> On pte side we have the same functionality open-coded. Should we do the
> same for pmd? Or change pte side the same way?

Sorry, I don't quite understand you. Do you mean pte_* functions?

Thanks,
Yang

>

2016-04-21 22:57:39

by Shi, Yang

[permalink] [raw]
Subject: Re: [PATCH] mm: move huge_pmd_set_accessed out of huge_memory.c

On 4/21/2016 2:15 AM, Hugh Dickins wrote:
> On Wed, 20 Apr 2016, Shi, Yang wrote:
>
>> Hi folks,
>>
>> I didn't realize pmd_* functions are protected by CONFIG_TRANSPARENT_HUGEPAGE
>> on the most architectures before I made this change.
>>
>> Before I fix all the affected architectures code, I want to check if you guys
>> think this change is worth or not?
>
> Thanks for asking: no, it is not worthwhile.
>
> I would much prefer not to have to consider these trivial cleanups
> in the huge memory area at this time. Kirill and I have urgent work
> to do in this area, and coping with patch conflicts between different
> versions of the source will not help any of us.

Thanks for your suggestion. I would consider to put such cleanup work on
the back burner.

Yang

>
> Thanks,
> Hugh
>
>>
>> Thanks,
>> Yang
>>
>> On 4/20/2016 11:24 AM, Yang Shi wrote:
>>> huge_pmd_set_accessed is only called by __handle_mm_fault from memory.c,
>>> move the definition to memory.c and make it static like create_huge_pmd and
>>> wp_huge_pmd.
>>>
>>> Signed-off-by: Yang Shi <[email protected]>
>>> ---
>>> include/linux/huge_mm.h | 4 ----
>>> mm/huge_memory.c | 23 -----------------------
>>> mm/memory.c | 23 +++++++++++++++++++++++
>>> 3 files changed, 23 insertions(+), 27 deletions(-)
>>>
>>> diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
>>> index 7008623..c218ab7b 100644
>>> --- a/include/linux/huge_mm.h
>>> +++ b/include/linux/huge_mm.h
>>> @@ -8,10 +8,6 @@ extern int do_huge_pmd_anonymous_page(struct mm_struct
>>> *mm,
>>> extern int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct
>>> *src_mm,
>>> pmd_t *dst_pmd, pmd_t *src_pmd, unsigned long addr,
>>> struct vm_area_struct *vma);
>>> -extern void huge_pmd_set_accessed(struct mm_struct *mm,
>>> - struct vm_area_struct *vma,
>>> - unsigned long address, pmd_t *pmd,
>>> - pmd_t orig_pmd, int dirty);
>>> extern int do_huge_pmd_wp_page(struct mm_struct *mm, struct
>>> vm_area_struct *vma,
>>> unsigned long address, pmd_t *pmd,
>>> pmd_t orig_pmd);
>>> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
>>> index fecbbc5..6c14cb6 100644
>>> --- a/mm/huge_memory.c
>>> +++ b/mm/huge_memory.c
>>> @@ -1137,29 +1137,6 @@ out:
>>> return ret;
>>> }
>>>
>>> -void huge_pmd_set_accessed(struct mm_struct *mm,
>>> - struct vm_area_struct *vma,
>>> - unsigned long address,
>>> - pmd_t *pmd, pmd_t orig_pmd,
>>> - int dirty)
>>> -{
>>> - spinlock_t *ptl;
>>> - pmd_t entry;
>>> - unsigned long haddr;
>>> -
>>> - ptl = pmd_lock(mm, pmd);
>>> - if (unlikely(!pmd_same(*pmd, orig_pmd)))
>>> - goto unlock;
>>> -
>>> - entry = pmd_mkyoung(orig_pmd);
>>> - haddr = address & HPAGE_PMD_MASK;
>>> - if (pmdp_set_access_flags(vma, haddr, pmd, entry, dirty))
>>> - update_mmu_cache_pmd(vma, address, pmd);
>>> -
>>> -unlock:
>>> - spin_unlock(ptl);
>>> -}
>>> -
>>> static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm,
>>> struct vm_area_struct *vma,
>>> unsigned long address,
>>> diff --git a/mm/memory.c b/mm/memory.c
>>> index 93897f2..6ced4eb 100644
>>> --- a/mm/memory.c
>>> +++ b/mm/memory.c
>>> @@ -3287,6 +3287,29 @@ static int wp_huge_pmd(struct mm_struct *mm, struct
>>> vm_area_struct *vma,
>>> return VM_FAULT_FALLBACK;
>>> }
>>>
>>> +static void huge_pmd_set_accessed(struct mm_struct *mm,
>>> + struct vm_area_struct *vma,
>>> + unsigned long address,
>>> + pmd_t *pmd, pmd_t orig_pmd,
>>> + int dirty)
>>> +{
>>> + spinlock_t *ptl;
>>> + pmd_t entry;
>>> + unsigned long haddr;
>>> +
>>> + ptl = pmd_lock(mm, pmd);
>>> + if (unlikely(!pmd_same(*pmd, orig_pmd)))
>>> + goto unlock;
>>> +
>>> + entry = pmd_mkyoung(orig_pmd);
>>> + haddr = address & HPAGE_PMD_MASK;
>>> + if (pmdp_set_access_flags(vma, haddr, pmd, entry, dirty))
>>> + update_mmu_cache_pmd(vma, address, pmd);
>>> +
>>> +unlock:
>>> + spin_unlock(ptl);
>>> +}
>>> +
>>> /*
>>> * These routines also need to handle stuff like marking pages dirty
>>> * and/or accessed for architectures that don't do it in hardware (most

2016-04-22 09:49:45

by Kirill A. Shutemov

[permalink] [raw]
Subject: Re: [PATCH] mm: move huge_pmd_set_accessed out of huge_memory.c

On Thu, Apr 21, 2016 at 03:56:07PM -0700, Shi, Yang wrote:
> On 4/21/2016 12:30 AM, Kirill A. Shutemov wrote:
> >On Wed, Apr 20, 2016 at 02:00:11PM -0700, Shi, Yang wrote:
> >>Hi folks,
> >>
> >>I didn't realize pmd_* functions are protected by
> >>CONFIG_TRANSPARENT_HUGEPAGE on the most architectures before I made this
> >>change.
> >>
> >>Before I fix all the affected architectures code, I want to check if you
> >>guys think this change is worth or not?
> >>
> >>Thanks,
> >>Yang
> >>
> >>On 4/20/2016 11:24 AM, Yang Shi wrote:
> >>>huge_pmd_set_accessed is only called by __handle_mm_fault from memory.c,
> >>>move the definition to memory.c and make it static like create_huge_pmd and
> >>>wp_huge_pmd.
> >>>
> >>>Signed-off-by: Yang Shi <[email protected]>
> >
> >On pte side we have the same functionality open-coded. Should we do the
> >same for pmd? Or change pte side the same way?
>
> Sorry, I don't quite understand you. Do you mean pte_* functions?

See handle_pte_fault(), we do the same for pte there what
huge_pmd_set_accessed() does for pmd.

I think we should be consistent here: either both are abstructed into
functions or both open-coded.

--
Kirill A. Shutemov

2016-04-29 18:09:41

by Shi, Yang

[permalink] [raw]
Subject: Re: [PATCH] mm: move huge_pmd_set_accessed out of huge_memory.c

On 4/22/2016 2:48 AM, Kirill A. Shutemov wrote:
> On Thu, Apr 21, 2016 at 03:56:07PM -0700, Shi, Yang wrote:
>> On 4/21/2016 12:30 AM, Kirill A. Shutemov wrote:
>>> On Wed, Apr 20, 2016 at 02:00:11PM -0700, Shi, Yang wrote:
>>>> Hi folks,
>>>>
>>>> I didn't realize pmd_* functions are protected by
>>>> CONFIG_TRANSPARENT_HUGEPAGE on the most architectures before I made this
>>>> change.
>>>>
>>>> Before I fix all the affected architectures code, I want to check if you
>>>> guys think this change is worth or not?
>>>>
>>>> Thanks,
>>>> Yang
>>>>
>>>> On 4/20/2016 11:24 AM, Yang Shi wrote:
>>>>> huge_pmd_set_accessed is only called by __handle_mm_fault from memory.c,
>>>>> move the definition to memory.c and make it static like create_huge_pmd and
>>>>> wp_huge_pmd.
>>>>>
>>>>> Signed-off-by: Yang Shi <[email protected]>
>>>
>>> On pte side we have the same functionality open-coded. Should we do the
>>> same for pmd? Or change pte side the same way?
>>
>> Sorry, I don't quite understand you. Do you mean pte_* functions?
>
> See handle_pte_fault(), we do the same for pte there what
> huge_pmd_set_accessed() does for pmd.

Thanks for directing to this code.

>
> I think we should be consistent here: either both are abstructed into
> functions or both open-coded.

I'm supposed functions sound better. However, do_wp_page has to be
called with pte lock acquired. So, the abstracted function has to call it.

Thanks,
Yang


>