Commit d71e53ce authored by Alexey Dobriyan's avatar Alexey Dobriyan Committed by Linus Torvalds

mm: shuffle GFP_* flags

GFP_KERNEL is one of the most used constant but on archs like arm with
fixed length instruction some constants are more equal than the others.
Constants with tightly packed bits can be injected directly into
instruction stream:

	   0:   e3a00d33        mov     r0, #3264       ; 0xcc0

Others require multiple instructions or even loading out of instruction
stream:

	   0:   e3a000c0        mov     r0, #192        ; 0xc0
	   4:   e3400060        movt    r0, #96		; 0x60

Shuffle GFP_* flags so that GFP_KERNEL/GFP_ATOMIC + __GFP_ZERO bits are
close to each other.

Savings on arm configs are ~0.1%.

Link: http://lkml.kernel.org/r/20190109201838.GA9140@avx2Signed-off-by: default avatarAlexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent e9f59873
...@@ -24,21 +24,21 @@ struct vm_area_struct; ...@@ -24,21 +24,21 @@ struct vm_area_struct;
#define ___GFP_HIGH 0x20u #define ___GFP_HIGH 0x20u
#define ___GFP_IO 0x40u #define ___GFP_IO 0x40u
#define ___GFP_FS 0x80u #define ___GFP_FS 0x80u
#define ___GFP_WRITE 0x100u #define ___GFP_ZERO 0x100u
#define ___GFP_NOWARN 0x200u #define ___GFP_ATOMIC 0x200u
#define ___GFP_RETRY_MAYFAIL 0x400u #define ___GFP_DIRECT_RECLAIM 0x400u
#define ___GFP_NOFAIL 0x800u #define ___GFP_KSWAPD_RECLAIM 0x800u
#define ___GFP_NORETRY 0x1000u #define ___GFP_WRITE 0x1000u
#define ___GFP_MEMALLOC 0x2000u #define ___GFP_NOWARN 0x2000u
#define ___GFP_COMP 0x4000u #define ___GFP_RETRY_MAYFAIL 0x4000u
#define ___GFP_ZERO 0x8000u #define ___GFP_NOFAIL 0x8000u
#define ___GFP_NOMEMALLOC 0x10000u #define ___GFP_NORETRY 0x10000u
#define ___GFP_HARDWALL 0x20000u #define ___GFP_MEMALLOC 0x20000u
#define ___GFP_THISNODE 0x40000u #define ___GFP_COMP 0x40000u
#define ___GFP_ATOMIC 0x80000u #define ___GFP_NOMEMALLOC 0x80000u
#define ___GFP_ACCOUNT 0x100000u #define ___GFP_HARDWALL 0x100000u
#define ___GFP_DIRECT_RECLAIM 0x200000u #define ___GFP_THISNODE 0x200000u
#define ___GFP_KSWAPD_RECLAIM 0x400000u #define ___GFP_ACCOUNT 0x400000u
#ifdef CONFIG_LOCKDEP #ifdef CONFIG_LOCKDEP
#define ___GFP_NOLOCKDEP 0x800000u #define ___GFP_NOLOCKDEP 0x800000u
#else #else
......
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