[PATCH] arch: uapi: asm: mman.h: Support MADV_FREE for madvise()

[PATCH] arch: uapi: asm: mman.h: Support MADV_FREE for madvise()

[Chen Gang]

At present, kernel supports madvise(MADV_FREE), so can benefit to all
related architectures (can grep MADV_WILLNEED or MADV_REMOVE in "arch/"
to know about all related architectures).

The related git commit: "4fb10ba mm: support madvise(MADV_FREE)".

The related error (with allmodconfig under parisc):

    CC      mm/madvise.o
  mm/madvise.c: In function 'madvise_need_mmap_write':
  mm/madvise.c:42:7: error: 'MADV_FREE' undeclared (first use in this function)
    case MADV_FREE:
       ^
  mm/madvise.c:42:7: note: each undeclared identifier is reported only once for each function it appears in
  mm/madvise.c: In function 'madvise_vma':
  mm/madvise.c:534:7: error: 'MADV_FREE' undeclared (first use in this function)
    case MADV_FREE:
       ^
  mm/madvise.c: In function 'madvise_behavior_valid':
  mm/madvise.c:561:7: error: 'MADV_FREE' undeclared (first use in this function)
    case MADV_FREE:
       ^
  make[1]: *** [mm/madvise.o] Error 1
  make: *** [mm] Error 2

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
---
 arch/alpha/include/uapi/asm/mman.h  | 1 +
 arch/mips/include/uapi/asm/mman.h   | 1 +
 arch/parisc/include/uapi/asm/mman.h | 1 +
 arch/xtensa/include/uapi/asm/mman.h | 1 +
 4 files changed, 4 insertions(+)

diff --git a/arch/alpha/include/uapi/asm/mman.h b/arch/alpha/include/uapi/asm/mman.h
index 0086b47..836fbd4 100644
--- a/arch/alpha/include/uapi/asm/mman.h
+++ b/arch/alpha/include/uapi/asm/mman.h
@@ -44,6 +44,7 @@
 #define MADV_WILLNEED	3		/* will need these pages */
 #define	MADV_SPACEAVAIL	5		/* ensure resources are available */
 #define MADV_DONTNEED	6		/* don't need these pages */
+#define MADV_FREE	7		/* free pages only if memory pressure */
 
 /* common/generic parameters */
 #define MADV_REMOVE	9		/* remove these pages & resources */
diff --git a/arch/mips/include/uapi/asm/mman.h b/arch/mips/include/uapi/asm/mman.h
index cfcb876..106e741 100644
--- a/arch/mips/include/uapi/asm/mman.h
+++ b/arch/mips/include/uapi/asm/mman.h
@@ -67,6 +67,7 @@
 #define MADV_SEQUENTIAL 2		/* expect sequential page references */
 #define MADV_WILLNEED	3		/* will need these pages */
 #define MADV_DONTNEED	4		/* don't need these pages */
+#define MADV_FREE	5		/* free pages only if memory pressure */
 
 /* common parameters: try to keep these consistent across architectures */
 #define MADV_REMOVE	9		/* remove these pages & resources */
diff --git a/arch/parisc/include/uapi/asm/mman.h b/arch/parisc/include/uapi/asm/mman.h
index 294d251..6cb8db7 100644
--- a/arch/parisc/include/uapi/asm/mman.h
+++ b/arch/parisc/include/uapi/asm/mman.h
@@ -40,6 +40,7 @@
 #define MADV_SPACEAVAIL 5               /* insure that resources are reserved */
 #define MADV_VPS_PURGE  6               /* Purge pages from VM page cache */
 #define MADV_VPS_INHERIT 7              /* Inherit parents page size */
+#define MADV_FREE	8		/* free pages only if memory pressure */
 
 /* common/generic parameters */
 #define MADV_REMOVE	9		/* remove these pages & resources */
diff --git a/arch/xtensa/include/uapi/asm/mman.h b/arch/xtensa/include/uapi/asm/mman.h
index 201aec0..1b19f25 100644
--- a/arch/xtensa/include/uapi/asm/mman.h
+++ b/arch/xtensa/include/uapi/asm/mman.h
@@ -80,6 +80,7 @@
 #define MADV_SEQUENTIAL	2		/* expect sequential page references */
 #define MADV_WILLNEED	3		/* will need these pages */
 #define MADV_DONTNEED	4		/* don't need these pages */
+#define MADV_FREE	5		/* free pages only if memory pressure */
 
 /* common parameters: try to keep these consistent across architectures */
 #define MADV_REMOVE	9		/* remove these pages & resources */
-- 
1.9.3

Re: [PATCH] arch: uapi: asm: mman.h: Support MADV_FREE for madvise()

[Max Filippov]

On Mon, Dec 1, 2014 at 11:43 PM, Chen Gang <gang.chen.5i5j@gmail.com> wrote:
> At present, kernel supports madvise(MADV_FREE), so can benefit to all
> related architectures (can grep MADV_WILLNEED or MADV_REMOVE in "arch/"
> to know about all related architectures).

A similar patch has been posted a while ago:

http://www.spinics.net/lists/linux-mm/msg81538.html

-- 
Thanks.
-- Max

Re: [PATCH] arch: uapi: asm: mman.h: Support MADV_FREE for madvise()

[Geert Uytterhoeven]

On Mon, Dec 1, 2014 at 9:52 PM, Max Filippov <jcmvbkbc@gmail.com> wrote:
> On Mon, Dec 1, 2014 at 11:43 PM, Chen Gang <gang.chen.5i5j@gmail.com> wrote:
>> At present, kernel supports madvise(MADV_FREE), so can benefit to all
>> related architectures (can grep MADV_WILLNEED or MADV_REMOVE in "arch/"
>> to know about all related architectures).
>
> A similar patch has been posted a while ago:
>
> http://www.spinics.net/lists/linux-mm/msg81538.html

Would it be possible to use the same number everywhere?

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH] arch: uapi: asm: mman.h: Support MADV_FREE for madvise()

[Carlos O'Donell]

On Mon, Dec 1, 2014 at 4:35 PM, Geert Uytterhoeven <geert@linux-m68k.org> wrote:
> On Mon, Dec 1, 2014 at 9:52 PM, Max Filippov <jcmvbkbc@gmail.com> wrote:
>> On Mon, Dec 1, 2014 at 11:43 PM, Chen Gang <gang.chen.5i5j@gmail.com> wrote:
>>> At present, kernel supports madvise(MADV_FREE), so can benefit to all
>>> related architectures (can grep MADV_WILLNEED or MADV_REMOVE in "arch/"
>>> to know about all related architectures).
>>
>> A similar patch has been posted a while ago:
>>
>> http://www.spinics.net/lists/linux-mm/msg81538.html
>
> Would it be possible to use the same number everywhere?

Yes please. It's ridiculous that we still need patches like this.

I proposed unifying all this two years ago, but didn't follow up.

From glibc's perspective it would be simpler if we started using the
same number everywhere.

http://www.spinics.net/lists/linux-api/msg02064.html

Cheers,
Carlos.

Re: [PATCH] arch: uapi: asm: mman.h: Support MADV_FREE for madvise()

[James Bottomley]

On Mon, 2014-12-01 at 17:01 -0500, Carlos O'Donell wrote:
> On Mon, Dec 1, 2014 at 4:35 PM, Geert Uytterhoeven <geert@linux-m68k.org> wrote:
> > On Mon, Dec 1, 2014 at 9:52 PM, Max Filippov <jcmvbkbc@gmail.com> wrote:
> >> On Mon, Dec 1, 2014 at 11:43 PM, Chen Gang <gang.chen.5i5j@gmail.com> wrote:
> >>> At present, kernel supports madvise(MADV_FREE), so can benefit to all
> >>> related architectures (can grep MADV_WILLNEED or MADV_REMOVE in "arch/"
> >>> to know about all related architectures).
> >>
> >> A similar patch has been posted a while ago:
> >>
> >> http://www.spinics.net/lists/linux-mm/msg81538.html
> >
> > Would it be possible to use the same number everywhere?
> 
> Yes please. It's ridiculous that we still need patches like this.
> 
> I proposed unifying all this two years ago, but didn't follow up.
> 
> From glibc's perspective it would be simpler if we started using the
> same number everywhere.
> 
> http://www.spinics.net/lists/linux-api/msg02064.html

Please co-ordinate with Andrew then because he's intent on merging this
patch:

http://marc.info/?l=linux-mm-commits&m=141747572930808

James

Re: [PATCH] arch: uapi: asm: mman.h: Support MADV_FREE for madvise()

[Chen Gang]

On 12/2/14 09:55, James Bottomley wrote:
> On Mon, 2014-12-01 at 17:01 -0500, Carlos O'Donell wrote:
>> On Mon, Dec 1, 2014 at 4:35 PM, Geert Uytterhoeven <geert@linux-m68k.org> wrote:
>>> On Mon, Dec 1, 2014 at 9:52 PM, Max Filippov <jcmvbkbc@gmail.com> wrote:
>>>> On Mon, Dec 1, 2014 at 11:43 PM, Chen Gang <gang.chen.5i5j@gmail.com> wrote:
>>>>> At present, kernel supports madvise(MADV_FREE), so can benefit to all
>>>>> related architectures (can grep MADV_WILLNEED or MADV_REMOVE in "arch/"
>>>>> to know about all related architectures).
>>>>
>>>> A similar patch has been posted a while ago:
>>>>
>>>> http://www.spinics.net/lists/linux-mm/msg81538.html
>>>
>>> Would it be possible to use the same number everywhere?
>>
>> Yes please. It's ridiculous that we still need patches like this.
>>
>> I proposed unifying all this two years ago, but didn't follow up.
>>
>> From glibc's perspective it would be simpler if we started using the
>> same number everywhere.
>>
>> http://www.spinics.net/lists/linux-api/msg02064.html
> 
> Please co-ordinate with Andrew then because he's intent on merging this
> patch:
> 
> http://marc.info/?l=linux-mm-commits&m=141747572930808
> 

For me, we can let MADV_FREE to 8 based on the Andrew's mm tree. Since
it is about uapi, we need try our best to let it perfect.


Thanks.
-- 
Chen Gang

Open, share, and attitude like air, water, and life which God blessed

Re: [PATCH] arch: uapi: asm: mman.h: Support MADV_FREE for madvise()

[Chen Gang]

On 12/2/14 06:01, Carlos O'Donell wrote:
> On Mon, Dec 1, 2014 at 4:35 PM, Geert Uytterhoeven <geert@linux-m68k.org> wrote:
>> On Mon, Dec 1, 2014 at 9:52 PM, Max Filippov <jcmvbkbc@gmail.com> wrote:
>>> On Mon, Dec 1, 2014 at 11:43 PM, Chen Gang <gang.chen.5i5j@gmail.com> wrote:
>>>> At present, kernel supports madvise(MADV_FREE), so can benefit to all
>>>> related architectures (can grep MADV_WILLNEED or MADV_REMOVE in "arch/"
>>>> to know about all related architectures).
>>>
>>> A similar patch has been posted a while ago:
>>>
>>> http://www.spinics.net/lists/linux-mm/msg81538.html
>>

OK, thanks.


>> Would it be possible to use the same number everywhere?
> 

For current patch, I guess, we can use '8' for it, since MADV_FREE in
asm-generic is merged just a few days ago (which is not used by user
mode), and parisc has to use '8'.

And welcome the related member's ideas.


> Yes please. It's ridiculous that we still need patches like this.
> 
> I proposed unifying all this two years ago, but didn't follow up.
> 
> From glibc's perspective it would be simpler if we started using the
> same number everywhere.
> 
> http://www.spinics.net/lists/linux-api/msg02064.html
> 

For me, we can divide it into 2 steps:

 - Let MADV_FREE has the same value (about current patch).

 - Let all shared MADV_* to "asm-generic" (about next patch, although I
   am not quite sure whether it is executable).


Thanks.
-- 
Chen Gang

Open, share, and attitude like air, water, and life which God blessed

[PATCH] arch: uapi: asm: mman.h: Support MADV_FREE for madvise()

[Chen Gang]

At present, kernel supports madvise(MADV_FREE), so can benefit to all
related architectures (can grep MADV_WILLNEED or MADV_REMOVE in "arch/"
to know about all related architectures).

The related git commit: "4fb10ba mm: support madvise(MADV_FREE)".

The related error (with allmodconfig under parisc):

    CC      mm/madvise.o
  mm/madvise.c: In function 'madvise_need_mmap_write':
  mm/madvise.c:42:7: error: 'MADV_FREE' undeclared (first use in this function)
    case MADV_FREE:
       ^
  mm/madvise.c:42:7: note: each undeclared identifier is reported only once for each function it appears in
  mm/madvise.c: In function 'madvise_vma':
  mm/madvise.c:534:7: error: 'MADV_FREE' undeclared (first use in this function)
    case MADV_FREE:
       ^
  mm/madvise.c: In function 'madvise_behavior_valid':
  mm/madvise.c:561:7: error: 'MADV_FREE' undeclared (first use in this function)
    case MADV_FREE:
       ^
  make[1]: *** [mm/madvise.o] Error 1
  make: *** [mm] Error 2

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
---
 arch/alpha/include/uapi/asm/mman.h  | 1 +
 arch/mips/include/uapi/asm/mman.h   | 1 +
 arch/parisc/include/uapi/asm/mman.h | 1 +
 arch/xtensa/include/uapi/asm/mman.h | 1 +
 4 files changed, 4 insertions(+)

diff --git a/arch/alpha/include/uapi/asm/mman.h b/arch/alpha/include/uapi/asm/mman.h
index 0086b47..836fbd4 100644
--- a/arch/alpha/include/uapi/asm/mman.h
+++ b/arch/alpha/include/uapi/asm/mman.h
@@ -44,6 +44,7 @@
 #define MADV_WILLNEED	3		/* will need these pages */
 #define	MADV_SPACEAVAIL	5		/* ensure resources are available */
 #define MADV_DONTNEED	6		/* don't need these pages */
+#define MADV_FREE	7		/* free pages only if memory pressure */
 
 /* common/generic parameters */
 #define MADV_REMOVE	9		/* remove these pages & resources */
diff --git a/arch/mips/include/uapi/asm/mman.h b/arch/mips/include/uapi/asm/mman.h
index cfcb876..106e741 100644
--- a/arch/mips/include/uapi/asm/mman.h
+++ b/arch/mips/include/uapi/asm/mman.h
@@ -67,6 +67,7 @@
 #define MADV_SEQUENTIAL 2		/* expect sequential page references */
 #define MADV_WILLNEED	3		/* will need these pages */
 #define MADV_DONTNEED	4		/* don't need these pages */
+#define MADV_FREE	5		/* free pages only if memory pressure */
 
 /* common parameters: try to keep these consistent across architectures */
 #define MADV_REMOVE	9		/* remove these pages & resources */
diff --git a/arch/parisc/include/uapi/asm/mman.h b/arch/parisc/include/uapi/asm/mman.h
index 294d251..6cb8db7 100644
--- a/arch/parisc/include/uapi/asm/mman.h
+++ b/arch/parisc/include/uapi/asm/mman.h
@@ -40,6 +40,7 @@
 #define MADV_SPACEAVAIL 5               /* insure that resources are reserved */
 #define MADV_VPS_PURGE  6               /* Purge pages from VM page cache */
 #define MADV_VPS_INHERIT 7              /* Inherit parents page size */
+#define MADV_FREE	8		/* free pages only if memory pressure */
 
 /* common/generic parameters */
 #define MADV_REMOVE	9		/* remove these pages & resources */
diff --git a/arch/xtensa/include/uapi/asm/mman.h b/arch/xtensa/include/uapi/asm/mman.h
index 201aec0..1b19f25 100644
--- a/arch/xtensa/include/uapi/asm/mman.h
+++ b/arch/xtensa/include/uapi/asm/mman.h
@@ -80,6 +80,7 @@
 #define MADV_SEQUENTIAL	2		/* expect sequential page references */
 #define MADV_WILLNEED	3		/* will need these pages */
 #define MADV_DONTNEED	4		/* don't need these pages */
+#define MADV_FREE	5		/* free pages only if memory pressure */
 
 /* common parameters: try to keep these consistent across architectures */
 #define MADV_REMOVE	9		/* remove these pages & resources */
-- 
1.9.3