diff mbox series

[07/16] powerpc: mm: Support MAP_BELOW_HINT

Message ID 20240827-patches-below_hint_mmap-v1-7-46ff2eb9022d@rivosinc.com (mailing list archive)
State Not Applicable
Headers show
Series mm: Introduce MAP_BELOW_HINT | expand

Commit Message

Charlie Jenkins Aug. 28, 2024, 5:49 a.m. UTC
Add support for MAP_BELOW_HINT to arch_get_mmap_base() and
arch_get_mmap_end().

Signed-off-by: Charlie Jenkins <charlie@rivosinc.com>
---
 arch/powerpc/include/asm/task_size_64.h | 36 +++++++++++++++++++++++++++------
 1 file changed, 30 insertions(+), 6 deletions(-)

Comments

Christophe Leroy Aug. 28, 2024, 6:34 a.m. UTC | #1
Hi Charlie,

Le 28/08/2024 à 07:49, Charlie Jenkins a écrit :
> Add support for MAP_BELOW_HINT to arch_get_mmap_base() and
> arch_get_mmap_end().
> 
> Signed-off-by: Charlie Jenkins <charlie@rivosinc.com>
> ---
>   arch/powerpc/include/asm/task_size_64.h | 36 +++++++++++++++++++++++++++------
>   1 file changed, 30 insertions(+), 6 deletions(-)
> 
> diff --git a/arch/powerpc/include/asm/task_size_64.h b/arch/powerpc/include/asm/task_size_64.h
> index 239b363841aa..a37a5a81365d 100644
> --- a/arch/powerpc/include/asm/task_size_64.h
> +++ b/arch/powerpc/include/asm/task_size_64.h
> @@ -72,12 +72,36 @@
>   #define STACK_TOP_MAX TASK_SIZE_USER64
>   #define STACK_TOP (is_32bit_task() ? STACK_TOP_USER32 : STACK_TOP_USER64)
>   
> -#define arch_get_mmap_base(addr, len, base, flags) \
> -	(((addr) > DEFAULT_MAP_WINDOW) ? (base) + TASK_SIZE - DEFAULT_MAP_WINDOW : (base))
> +#define arch_get_mmap_base(addr, len, base, flags)					\

This macro looks quite big for a macro, can it be a static inline 
function instead ? Same for the other macro below.

> +({											\
> +	unsigned long mmap_base;							\
> +	typeof(flags) _flags = (flags);							\
> +	typeof(addr) _addr = (addr);							\
> +	typeof(base) _base = (base);							\
> +	typeof(len) _len = (len);							\
> +	unsigned long rnd_gap = DEFAULT_MAP_WINDOW - (_base);				\
> +	if (_flags & MAP_BELOW_HINT && _addr != 0 && ((_addr + _len) > BIT(VA_BITS - 1)))\
> +		mmap_base = (_addr + _len) - rnd_gap;					\
> +	else										\
> +		mmap_end = ((_addr > DEFAULT_MAP_WINDOW) ?				\
> +				_base + TASK_SIZE - DEFAULT_MAP_WINDOW :		\
> +				_base);							\
> +	mmap_end;									\

mmap_end doesn't exist, did you mean mmap_base ?

> +})
>   
> -#define arch_get_mmap_end(addr, len, flags) \
> -	(((addr) > DEFAULT_MAP_WINDOW) || \
> -	 (((flags) & MAP_FIXED) && ((addr) + (len) > DEFAULT_MAP_WINDOW)) ? TASK_SIZE : \
> -									    DEFAULT_MAP_WINDOW)
> +#define arch_get_mmap_end(addr, len, flags)							\
> +({												\
> +	unsigned long mmap_end;									\
> +	typeof(flags) _flags = (flags);								\
> +	typeof(addr) _addr = (addr);								\
> +	typeof(len) _len = (len);								\
> +	if (_flags & MAP_BELOW_HINT && _addr != 0 && ((_addr + _len) > BIT(VA_BITS - 1)))	\
> +		mmap_end = (_addr + _len);							\
> +	else											\
> +		mmap_end = (((_addr) > DEFAULT_MAP_WINDOW) ||					\
> +				(((_flags) & MAP_FIXED) && ((_addr) + (_len) > DEFAULT_MAP_WINDOW))\
> +				? TASK_SIZE : DEFAULT_MAP_WINDOW)				\
> +	mmap_end;										\
> +})
>   
>   #endif /* _ASM_POWERPC_TASK_SIZE_64_H */
>
Charlie Jenkins Aug. 28, 2024, 5:29 p.m. UTC | #2
On Wed, Aug 28, 2024 at 08:34:49AM +0200, Christophe Leroy wrote:
> Hi Charlie,
> 
> Le 28/08/2024 à 07:49, Charlie Jenkins a écrit :
> > Add support for MAP_BELOW_HINT to arch_get_mmap_base() and
> > arch_get_mmap_end().
> > 
> > Signed-off-by: Charlie Jenkins <charlie@rivosinc.com>
> > ---
> >   arch/powerpc/include/asm/task_size_64.h | 36 +++++++++++++++++++++++++++------
> >   1 file changed, 30 insertions(+), 6 deletions(-)
> > 
> > diff --git a/arch/powerpc/include/asm/task_size_64.h b/arch/powerpc/include/asm/task_size_64.h
> > index 239b363841aa..a37a5a81365d 100644
> > --- a/arch/powerpc/include/asm/task_size_64.h
> > +++ b/arch/powerpc/include/asm/task_size_64.h
> > @@ -72,12 +72,36 @@
> >   #define STACK_TOP_MAX TASK_SIZE_USER64
> >   #define STACK_TOP (is_32bit_task() ? STACK_TOP_USER32 : STACK_TOP_USER64)
> > -#define arch_get_mmap_base(addr, len, base, flags) \
> > -	(((addr) > DEFAULT_MAP_WINDOW) ? (base) + TASK_SIZE - DEFAULT_MAP_WINDOW : (base))
> > +#define arch_get_mmap_base(addr, len, base, flags)					\
> 
> This macro looks quite big for a macro, can it be a static inline function
> instead ? Same for the other macro below.
> 

I had overlooked that possibility, I think that's a great solution, I
will change that.

> > +({											\
> > +	unsigned long mmap_base;							\
> > +	typeof(flags) _flags = (flags);							\
> > +	typeof(addr) _addr = (addr);							\
> > +	typeof(base) _base = (base);							\
> > +	typeof(len) _len = (len);							\
> > +	unsigned long rnd_gap = DEFAULT_MAP_WINDOW - (_base);				\
> > +	if (_flags & MAP_BELOW_HINT && _addr != 0 && ((_addr + _len) > BIT(VA_BITS - 1)))\
> > +		mmap_base = (_addr + _len) - rnd_gap;					\
> > +	else										\
> > +		mmap_end = ((_addr > DEFAULT_MAP_WINDOW) ?				\
> > +				_base + TASK_SIZE - DEFAULT_MAP_WINDOW :		\
> > +				_base);							\
> > +	mmap_end;									\
> 
> mmap_end doesn't exist, did you mean mmap_base ?

Oh whoops, thank you!

- Charlie

> 
> > +})
> > -#define arch_get_mmap_end(addr, len, flags) \
> > -	(((addr) > DEFAULT_MAP_WINDOW) || \
> > -	 (((flags) & MAP_FIXED) && ((addr) + (len) > DEFAULT_MAP_WINDOW)) ? TASK_SIZE : \
> > -									    DEFAULT_MAP_WINDOW)
> > +#define arch_get_mmap_end(addr, len, flags)							\
> > +({												\
> > +	unsigned long mmap_end;									\
> > +	typeof(flags) _flags = (flags);								\
> > +	typeof(addr) _addr = (addr);								\
> > +	typeof(len) _len = (len);								\
> > +	if (_flags & MAP_BELOW_HINT && _addr != 0 && ((_addr + _len) > BIT(VA_BITS - 1)))	\
> > +		mmap_end = (_addr + _len);							\
> > +	else											\
> > +		mmap_end = (((_addr) > DEFAULT_MAP_WINDOW) ||					\
> > +				(((_flags) & MAP_FIXED) && ((_addr) + (_len) > DEFAULT_MAP_WINDOW))\
> > +				? TASK_SIZE : DEFAULT_MAP_WINDOW)				\
> > +	mmap_end;										\
> > +})
> >   #endif /* _ASM_POWERPC_TASK_SIZE_64_H */
> >
David Laight Aug. 31, 2024, 4:30 p.m. UTC | #3
From: Christophe Leroy
> Sent: 28 August 2024 07:35
> Hi Charlie,
> 
> Le 28/08/2024 à 07:49, Charlie Jenkins a écrit :
> > Add support for MAP_BELOW_HINT to arch_get_mmap_base() and
> > arch_get_mmap_end().
> >
> > Signed-off-by: Charlie Jenkins <charlie@rivosinc.com>
> > ---
> >   arch/powerpc/include/asm/task_size_64.h | 36 +++++++++++++++++++++++++++------
> >   1 file changed, 30 insertions(+), 6 deletions(-)
> >
> > diff --git a/arch/powerpc/include/asm/task_size_64.h b/arch/powerpc/include/asm/task_size_64.h
> > index 239b363841aa..a37a5a81365d 100644
> > --- a/arch/powerpc/include/asm/task_size_64.h
> > +++ b/arch/powerpc/include/asm/task_size_64.h
> > @@ -72,12 +72,36 @@
> >   #define STACK_TOP_MAX TASK_SIZE_USER64
> >   #define STACK_TOP (is_32bit_task() ? STACK_TOP_USER32 : STACK_TOP_USER64)
> >
> > -#define arch_get_mmap_base(addr, len, base, flags) \
> > -	(((addr) > DEFAULT_MAP_WINDOW) ? (base) + TASK_SIZE - DEFAULT_MAP_WINDOW : (base))
> > +#define arch_get_mmap_base(addr, len, base, flags)					\
> 
> This macro looks quite big for a macro, can it be a static inline
> function instead ? Same for the other macro below.

Or even a real function?
Given the actual cost of mapping memory an extra function call
isn't going to be masurable.

	David

> 
> > +({											\
> > +	unsigned long mmap_base;							\
> > +	typeof(flags) _flags = (flags);							\
> > +	typeof(addr) _addr = (addr);							\
> > +	typeof(base) _base = (base);							\
> > +	typeof(len) _len = (len);							\
> > +	unsigned long rnd_gap = DEFAULT_MAP_WINDOW - (_base);				\
> > +	if (_flags & MAP_BELOW_HINT && _addr != 0 && ((_addr + _len) > BIT(VA_BITS - 1)))\
> > +		mmap_base = (_addr + _len) - rnd_gap;					\
> > +	else										\
> > +		mmap_end = ((_addr > DEFAULT_MAP_WINDOW) ?				\
> > +				_base + TASK_SIZE - DEFAULT_MAP_WINDOW :		\
> > +				_base);							\
> > +	mmap_end;									\
> 
> mmap_end doesn't exist, did you mean mmap_base ?
> 
> > +})
> >
> > -#define arch_get_mmap_end(addr, len, flags) \
> > -	(((addr) > DEFAULT_MAP_WINDOW) || \
> > -	 (((flags) & MAP_FIXED) && ((addr) + (len) > DEFAULT_MAP_WINDOW)) ? TASK_SIZE : \
> > -									    DEFAULT_MAP_WINDOW)
> > +#define arch_get_mmap_end(addr, len, flags)							\
> > +({												\
> > +	unsigned long mmap_end;									\
> > +	typeof(flags) _flags = (flags);								\
> > +	typeof(addr) _addr = (addr);								\
> > +	typeof(len) _len = (len);								\
> > +	if (_flags & MAP_BELOW_HINT && _addr != 0 && ((_addr + _len) > BIT(VA_BITS - 1)))	\
> > +		mmap_end = (_addr + _len);							\
> > +	else											\
> > +		mmap_end = (((_addr) > DEFAULT_MAP_WINDOW) ||					\
> > +				(((_flags) & MAP_FIXED) && ((_addr) + (_len) > DEFAULT_MAP_WINDOW))\
> > +				? TASK_SIZE : DEFAULT_MAP_WINDOW)				\
> > +	mmap_end;										\
> > +})
> >
> >   #endif /* _ASM_POWERPC_TASK_SIZE_64_H */
> >

-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)
diff mbox series

Patch

diff --git a/arch/powerpc/include/asm/task_size_64.h b/arch/powerpc/include/asm/task_size_64.h
index 239b363841aa..a37a5a81365d 100644
--- a/arch/powerpc/include/asm/task_size_64.h
+++ b/arch/powerpc/include/asm/task_size_64.h
@@ -72,12 +72,36 @@ 
 #define STACK_TOP_MAX TASK_SIZE_USER64
 #define STACK_TOP (is_32bit_task() ? STACK_TOP_USER32 : STACK_TOP_USER64)
 
-#define arch_get_mmap_base(addr, len, base, flags) \
-	(((addr) > DEFAULT_MAP_WINDOW) ? (base) + TASK_SIZE - DEFAULT_MAP_WINDOW : (base))
+#define arch_get_mmap_base(addr, len, base, flags)					\
+({											\
+	unsigned long mmap_base;							\
+	typeof(flags) _flags = (flags);							\
+	typeof(addr) _addr = (addr);							\
+	typeof(base) _base = (base);							\
+	typeof(len) _len = (len);							\
+	unsigned long rnd_gap = DEFAULT_MAP_WINDOW - (_base);				\
+	if (_flags & MAP_BELOW_HINT && _addr != 0 && ((_addr + _len) > BIT(VA_BITS - 1)))\
+		mmap_base = (_addr + _len) - rnd_gap;					\
+	else										\
+		mmap_end = ((_addr > DEFAULT_MAP_WINDOW) ?				\
+				_base + TASK_SIZE - DEFAULT_MAP_WINDOW :		\
+				_base);							\
+	mmap_end;									\
+})
 
-#define arch_get_mmap_end(addr, len, flags) \
-	(((addr) > DEFAULT_MAP_WINDOW) || \
-	 (((flags) & MAP_FIXED) && ((addr) + (len) > DEFAULT_MAP_WINDOW)) ? TASK_SIZE : \
-									    DEFAULT_MAP_WINDOW)
+#define arch_get_mmap_end(addr, len, flags)							\
+({												\
+	unsigned long mmap_end;									\
+	typeof(flags) _flags = (flags);								\
+	typeof(addr) _addr = (addr);								\
+	typeof(len) _len = (len);								\
+	if (_flags & MAP_BELOW_HINT && _addr != 0 && ((_addr + _len) > BIT(VA_BITS - 1)))	\
+		mmap_end = (_addr + _len);							\
+	else											\
+		mmap_end = (((_addr) > DEFAULT_MAP_WINDOW) ||					\
+				(((_flags) & MAP_FIXED) && ((_addr) + (_len) > DEFAULT_MAP_WINDOW))\
+				? TASK_SIZE : DEFAULT_MAP_WINDOW)				\
+	mmap_end;										\
+})
 
 #endif /* _ASM_POWERPC_TASK_SIZE_64_H */