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pc64: avoid getcr3() in mmuflushtlb()

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it turns out that calculating physical address of pml4 is faster
than reading the machine register, so pass it explicitely.
This commit is contained in:
cinap_lenrek 2021-05-12 22:40:51 +02:00
parent 18b3847aef
commit 15b903c4e1
3 changed files with 4 additions and 4 deletions
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2
sys/src/9/pc64/fns.h
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@ -96,7 +96,7 @@ void meminit(void);
void meminit0(void); void meminit0(void);
void memreserve(uintptr, uintptr); void memreserve(uintptr, uintptr);
void mfence(void); void mfence(void);
#define mmuflushtlb() putcr3(getcr3()) #define mmuflushtlb(pml4) putcr3(pml4)
void mmuinit(void); void mmuinit(void);
uintptr *mmuwalk(uintptr*, uintptr, int, int); uintptr *mmuwalk(uintptr*, uintptr, int, int);
char* mtrr(uvlong, uvlong, char *); char* mtrr(uvlong, uvlong, char *);

4
sys/src/9/pc64/main.c
View file

@ -239,7 +239,7 @@ rebootjump(uintptr entry, uintptr code, ulong size)
if((pte = mmuwalk(m->pml4, REBOOTADDR, 0, 0)) != nil) if((pte = mmuwalk(m->pml4, REBOOTADDR, 0, 0)) != nil)
*pte &= ~PTENOEXEC; *pte &= ~PTENOEXEC;
mmuflushtlb(); mmuflushtlb(PADDR(m->pml4));
/* setup reboot trampoline function */ /* setup reboot trampoline function */
f = (void*)REBOOTADDR; f = (void*)REBOOTADDR;
@ -350,5 +350,5 @@ procsave(Proc *p)
* You might think it would be a win not to do this in that case, * You might think it would be a win not to do this in that case,
* especially on VMware, but it turns out not to matter. * especially on VMware, but it turns out not to matter.
*/ */
mmuflushtlb(); mmuflushtlb(PADDR(m->pml4));
} }

2
sys/src/9/pc64/mmu.c
View file

@ -67,7 +67,7 @@ taskswitch(uintptr stack)
tss->rsp1[1] = stack >> 32; tss->rsp1[1] = stack >> 32;
tss->rsp2[0] = (u32int)stack; tss->rsp2[0] = (u32int)stack;
tss->rsp2[1] = stack >> 32; tss->rsp2[1] = stack >> 32;
mmuflushtlb(); mmuflushtlb(PADDR(m->pml4));
} }
static void kernelro(void); static void kernelro(void);