linux/arch/x86/include/asm/mmu_context_32.h
Jan Beulich cfc319833b x86, 32-bit: improve lazy TLB handling code
Impact: micro-optimize the 32-bit TLB flush code

Use the faster x86_{read,write}_percpu() accessors here.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-16 18:47:17 +01:00

56 lines
1.4 KiB
C

#ifndef _ASM_X86_MMU_CONTEXT_32_H
#define _ASM_X86_MMU_CONTEXT_32_H
static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
{
#ifdef CONFIG_SMP
if (x86_read_percpu(cpu_tlbstate.state) == TLBSTATE_OK)
x86_write_percpu(cpu_tlbstate.state, TLBSTATE_LAZY);
#endif
}
static inline void switch_mm(struct mm_struct *prev,
struct mm_struct *next,
struct task_struct *tsk)
{
int cpu = smp_processor_id();
if (likely(prev != next)) {
/* stop flush ipis for the previous mm */
cpu_clear(cpu, prev->cpu_vm_mask);
#ifdef CONFIG_SMP
x86_write_percpu(cpu_tlbstate.state, TLBSTATE_OK);
x86_write_percpu(cpu_tlbstate.active_mm, next);
#endif
cpu_set(cpu, next->cpu_vm_mask);
/* Re-load page tables */
load_cr3(next->pgd);
/*
* load the LDT, if the LDT is different:
*/
if (unlikely(prev->context.ldt != next->context.ldt))
load_LDT_nolock(&next->context);
}
#ifdef CONFIG_SMP
else {
x86_write_percpu(cpu_tlbstate.state, TLBSTATE_OK);
BUG_ON(x86_read_percpu(cpu_tlbstate.active_mm) != next);
if (!cpu_test_and_set(cpu, next->cpu_vm_mask)) {
/* We were in lazy tlb mode and leave_mm disabled
* tlb flush IPI delivery. We must reload %cr3.
*/
load_cr3(next->pgd);
load_LDT_nolock(&next->context);
}
}
#endif
}
#define deactivate_mm(tsk, mm) \
asm("movl %0,%%gs": :"r" (0));
#endif /* _ASM_X86_MMU_CONTEXT_32_H */