mirror of
https://github.com/torvalds/linux.git
synced 2024-11-07 20:51:47 +00:00
af6a25f0e1
Reorder mm_context_t to remove alignment padding on 64 bit
builds shrinking its size from 64 to 56 bytes.
This allows mm_struct to shrink from 840 to 832 bytes, so using
one fewer cache lines, and getting more objects per slab when
using slub.
slabinfo mm_struct reports
before :-
Sizes (bytes) Slabs
-----------------------------------
Object : 840 Total : 7
SlabObj: 896 Full : 1
SlabSiz: 16384 Partial: 4
Loss : 56 CpuSlab: 2
Align : 64 Objects: 18
after :-
Sizes (bytes) Slabs
----------------------------------
Object : 832 Total : 7
SlabObj: 832 Full : 1
SlabSiz: 16384 Partial: 4
Loss : 0 CpuSlab: 2
Align : 64 Objects: 19
Signed-off-by: Richard Kennedy <richard@rsk.demon.co.uk>
Cc: wilsons@start.ca
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Pekka Enberg <penberg@kernel.org>
Link: http://lkml.kernel.org/r/1306244999.1999.5.camel@castor.rsk
Signed-off-by: Ingo Molnar <mingo@elte.hu>
33 lines
537 B
C
33 lines
537 B
C
#ifndef _ASM_X86_MMU_H
|
|
#define _ASM_X86_MMU_H
|
|
|
|
#include <linux/spinlock.h>
|
|
#include <linux/mutex.h>
|
|
|
|
/*
|
|
* The x86 doesn't have a mmu context, but
|
|
* we put the segment information here.
|
|
*/
|
|
typedef struct {
|
|
void *ldt;
|
|
int size;
|
|
|
|
#ifdef CONFIG_X86_64
|
|
/* True if mm supports a task running in 32 bit compatibility mode. */
|
|
unsigned short ia32_compat;
|
|
#endif
|
|
|
|
struct mutex lock;
|
|
void *vdso;
|
|
} mm_context_t;
|
|
|
|
#ifdef CONFIG_SMP
|
|
void leave_mm(int cpu);
|
|
#else
|
|
static inline void leave_mm(int cpu)
|
|
{
|
|
}
|
|
#endif
|
|
|
|
#endif /* _ASM_X86_MMU_H */
|