diff options
Diffstat (limited to 'sys/i386/i386/swtch.s')
| -rw-r--r-- | sys/i386/i386/swtch.s | 63 |
1 files changed, 18 insertions, 45 deletions
diff --git a/sys/i386/i386/swtch.s b/sys/i386/i386/swtch.s index 571d9c9dbc8b..62a970296c26 100644 --- a/sys/i386/i386/swtch.s +++ b/sys/i386/i386/swtch.s @@ -33,7 +33,7 @@ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * - * $Id: swtch.s,v 1.16 1994/10/25 07:25:56 davidg Exp $ + * $Id: swtch.s,v 1.17 1994/10/30 20:09:13 bde Exp $ */ #include "npx.h" /* for NNPX */ @@ -250,13 +250,19 @@ _idle: ALIGN_TEXT idle_loop: cli + movb $1,_intr_nesting_level /* charge Intr if we leave */ cmpl $0,_whichrtqs /* real-time queue */ jne sw1a cmpl $0,_whichqs /* normal queue */ jne nortqr cmpl $0,_whichidqs /* 'idle' queue */ jne idqr + movb $0,_intr_nesting_level /* charge Idle for this loop */ #ifdef APM + /* + * XXX it breaks the rules to call a function while interrupts are + * disabled. How long before apm enables them? + */ call _apm_cpu_idle call _apm_cpu_busy #else @@ -294,24 +300,24 @@ ENTRY(cpu_switch) movl %esi,PCB_ESI(%ecx) movl %edi,PCB_EDI(%ecx) + movb _intr_nesting_level,%al + movb %al,PCB_INL(%ecx) + #if NNPX > 0 /* have we used fp, and need a save? */ mov _curproc,%eax cmp %eax,_npxproc jne 1f - pushl %ecx /* h/w bugs make saving complicated */ - leal PCB_SAVEFPU(%ecx),%eax - pushl %eax + addl $PCB_SAVEFPU,%ecx /* h/w bugs make saving complicated */ + pushl %ecx call _npxsave /* do it in a big C function */ popl %eax - popl %ecx 1: #endif /* NNPX > 0 */ - movl $0,_curproc /* out of process */ + movb $1,_intr_nesting_level /* charge Intr, not Sys/Idle */ -# movw _cpl,%ax -# movw %ax,PCB_IML(%ecx) /* save ipl */ + movl $0,_curproc /* out of process */ /* save is done, now choose a new process or idle */ sw1: @@ -436,8 +442,11 @@ swtch_com: movl PCB_EIP(%edx),%eax movl %eax,(%esp) - movl %ecx,_curproc /* into next process */ movl %edx,_curpcb + movl %ecx,_curproc /* into next process */ + + movb PCB_INL(%edx),%al + movb %al,_intr_nesting_level #ifdef USER_LDT cmpl $0, PCB_USERLDT(%edx) @@ -454,46 +463,12 @@ swtch_com: 2: #endif - pushl %edx /* save p to return */ -/* - * XXX - 0.0 forgot to save it - is that why this was commented out in 0.1? - * I think restoring the cpl is unnecessary, but we must turn off the cli - * now that spl*() don't do it as a side affect. - */ - pushl PCB_IML(%edx) sti -#if 0 - call _splx -#endif - addl $4,%esp -/* - * XXX - 0.0 gets here via swtch_to_inactive(). I think 0.1 gets here in the - * same way. Better return a value. - */ - popl %eax /* return(p); */ ret ENTRY(mvesp) movl %esp,%eax ret -/* - * struct proc *swtch_to_inactive(struct proc *p); - * - * At exit of a process, move off the address space of the - * process and onto a "safe" one. Then, on a temporary stack - * return and run code that disposes of the old state. - * Since this code requires a parameter from the "old" stack, - * pass it back as a return value. - */ -ENTRY(swtch_to_inactive) - popl %edx /* old pc */ - popl %eax /* arg, our return value */ - movl _IdlePTD,%ecx - movl %ecx,%cr3 /* good bye address space */ - #write buffer? - movl $tmpstk,%esp /* temporary stack, compensated for call */ - MEXITCOUNT - jmp %edx /* return, execute remainder of cleanup */ /* * savectx(pcb, altreturn) @@ -502,8 +477,6 @@ ENTRY(swtch_to_inactive) */ ENTRY(savectx) movl 4(%esp),%ecx - movw _cpl,%ax - movw %ax,PCB_IML(%ecx) movl (%esp),%eax movl %eax,PCB_EIP(%ecx) movl %ebx,PCB_EBX(%ecx) |