diff options
Diffstat (limited to 'sys/i386/i386/swtch.s')
-rw-r--r-- | sys/i386/i386/swtch.s | 78 |
1 files changed, 43 insertions, 35 deletions
diff --git a/sys/i386/i386/swtch.s b/sys/i386/i386/swtch.s index 0f2f7a8..075aa36 100644 --- a/sys/i386/i386/swtch.s +++ b/sys/i386/i386/swtch.s @@ -77,17 +77,17 @@ ENTRY(cpu_throw) ENTRY(cpu_switch) /* switch to new process. first, save context as needed */ - movl PCPU(CURPROC),%ecx + movl PCPU(CURTHREAD),%ecx /* if no process to save, don't bother */ testl %ecx,%ecx jz sw1 - - movl P_VMSPACE(%ecx), %edx + movl TD_PROC(%ecx), %eax + movl P_VMSPACE(%eax), %edx movl PCPU(CPUID), %eax btrl %eax, VM_PMAP+PM_ACTIVE(%edx) - movl P_ADDR(%ecx),%edx + movl TD_PCB(%ecx),%edx movl (%esp),%eax /* Hardware registers */ movl %eax,PCB_EIP(%edx) @@ -124,7 +124,7 @@ ENTRY(cpu_switch) #ifdef DEV_NPX /* have we used fp, and need a save? */ - cmpl %ecx,PCPU(NPXPROC) + cmpl %ecx,PCPU(NPXTHREAD) jne 1f addl $PCB_SAVEFPU,%edx /* h/w bugs make saving complicated */ pushl %edx @@ -133,7 +133,11 @@ ENTRY(cpu_switch) 1: #endif /* DEV_NPX */ +/*##########################################################################*/ +/*##########################################################################*/ +/*##########################################################################*/ /* save is done, now choose a new process */ + /* But still trashing space above the old "Top Of Stack".. */ sw1: #ifdef SMP @@ -143,17 +147,17 @@ sw1: cmpl $0,PCPU(CPUID) je 1f - movl PCPU(IDLEPROC), %eax - jmp sw1b + movl PCPU(IDLETHREAD), %eax + jmp sw1b /* Idle thread can run on any kernel context */ 1: #endif /* - * Choose a new process to schedule. chooseproc() returns idleproc + * Choose a new process to schedule. choosethread() returns idleproc * if it cannot find another process to run. */ sw1a: - call chooseproc /* trash ecx, edx, ret eax*/ + call choosethread /* trash ecx, edx, ret eax*/ #ifdef INVARIANTS testl %eax,%eax /* no process? */ @@ -163,15 +167,20 @@ sw1b: movl %eax,%ecx #ifdef INVARIANTS - cmpb $SRUN,P_STAT(%ecx) + movl TD_PROC(%ecx), %eax /* XXXKSE */ + cmpb $SRUN,P_STAT(%eax) jne badsw2 #endif - movl P_ADDR(%ecx),%edx + movl TD_PCB(%ecx),%edx #if defined(SWTCH_OPTIM_STATS) incl swtch_optim_stats #endif + +/*##########################################################################*/ +/*##########################################################################*/ +/*##########################################################################*/ /* switch address space */ movl %cr3,%ebx cmpl PCB_CR3(%edx),%ebx @@ -181,9 +190,8 @@ sw1b: incl tlb_flush_count #endif movl PCB_CR3(%edx),%ebx - movl %ebx,%cr3 + movl %ebx,%cr3 /* LOAD NEW PAGE TABLES */ 4: - movl PCPU(CPUID), %esi cmpl $0, PCB_EXT(%edx) /* has pcb extension? */ je 1f @@ -191,12 +199,9 @@ sw1b: movl PCB_EXT(%edx), %edi /* new tss descriptor */ jmp 2f 1: - /* update common_tss.tss_esp0 pointer */ - movl %edx, %ebx /* pcb */ - addl $(UPAGES * PAGE_SIZE - 16), %ebx - movl %ebx, PCPU(COMMON_TSS) + TSS_ESP0 - + /* esp points to base of usable stack */ + movl %edx, PCPU(COMMON_TSS) + TSS_ESP0 /* stack is below pcb */ btrl %esi, private_tss jae 3f PCPU_ADDR(COMMON_TSSD, %edi) @@ -210,7 +215,9 @@ sw1b: movl $GPROC0_SEL*8, %esi /* GSEL(entry, SEL_KPL) */ ltr %si 3: - movl P_VMSPACE(%ecx), %ebx + /* note in a vmspace that this cpu is using it */ + movl TD_PROC(%ecx),%eax /* get proc from thread XXXKSE */ + movl P_VMSPACE(%eax), %ebx /* get vmspace of proc */ movl PCPU(CPUID), %eax btsl %eax, VM_PMAP+PM_ACTIVE(%ebx) @@ -233,22 +240,23 @@ sw1b: #endif /** GRAB_LOPRIO */ #endif /* SMP */ movl %edx, PCPU(CURPCB) - movl %ecx, PCPU(CURPROC) /* into next process */ + movl %ecx, PCPU(CURTHREAD) /* into next process */ #ifdef SMP /* XXX FIXME: we should be restoring the local APIC TPR */ #endif /* SMP */ - cmpl $0, PCB_USERLDT(%edx) - jnz 1f - movl _default_ldt,%eax - cmpl PCPU(CURRENTLDT),%eax - je 2f - lldt _default_ldt - movl %eax,PCPU(CURRENTLDT) + cmpl $0, PCB_USERLDT(%edx) /* if there is one */ + jnz 1f /* then use it */ + movl _default_ldt,%eax /* We will use the default */ + cmpl PCPU(CURRENTLDT),%eax /* check to see if already loaded */ + je 2f /* if so skip reload */ + lldt _default_ldt /* load the default... we trust it. */ + movl %eax,PCPU(CURRENTLDT) /* store what we have */ jmp 2f -1: pushl %edx - call set_user_ldt + +1: pushl %edx /* call a non-trusting routine */ + call set_user_ldt /* to check and load the ldt */ popl %edx 2: @@ -275,7 +283,7 @@ cpu_switch_load_gs: andl $0x0000fc00,%eax /* reserved bits */ pushl %ebx movl PCB_DR7(%edx),%ebx - andl $~0x0000fc00,%ebx + andl $~0x0000fc00,%ebx /* re-enable the restored watchpoints */ orl %ebx,%eax popl %ebx movl %eax,%dr7 @@ -322,25 +330,25 @@ ENTRY(savectx) #ifdef DEV_NPX /* - * If npxproc == NULL, then the npx h/w state is irrelevant and the + * If npxthread == NULL, then the npx h/w state is irrelevant and the * state had better already be in the pcb. This is true for forks * but not for dumps (the old book-keeping with FP flags in the pcb * always lost for dumps because the dump pcb has 0 flags). * - * If npxproc != NULL, then we have to save the npx h/w state to - * npxproc's pcb and copy it to the requested pcb, or save to the + * If npxthread != NULL, then we have to save the npx h/w state to + * npxthread's pcb and copy it to the requested pcb, or save to the * requested pcb and reload. Copying is easier because we would * have to handle h/w bugs for reloading. We used to lose the * parent's npx state for forks by forgetting to reload. */ pushfl cli - movl PCPU(NPXPROC),%eax + movl PCPU(NPXTHREAD),%eax testl %eax,%eax je 1f pushl %ecx - movl P_ADDR(%eax),%eax + movl TD_PCB(%eax),%eax leal PCB_SAVEFPU(%eax),%eax pushl %eax pushl %eax |