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>
32 lines
537 B
C
32 lines
537 B
C
#ifndef _ASM_X86_MMU_H
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#define _ASM_X86_MMU_H
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#include <linux/spinlock.h>
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#include <linux/mutex.h>
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/*
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* The x86 doesn't have a mmu context, but
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* we put the segment information here.
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*/
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typedef struct {
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void *ldt;
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int size;
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#ifdef CONFIG_X86_64
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/* True if mm supports a task running in 32 bit compatibility mode. */
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unsigned short ia32_compat;
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#endif
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struct mutex lock;
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void *vdso;
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} mm_context_t;
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#ifdef CONFIG_SMP
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void leave_mm(int cpu);
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#else
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static inline void leave_mm(int cpu)
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{
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}
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#endif
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#endif /* _ASM_X86_MMU_H */
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