Windows2000/private/ntos/ke/ia64/ctxswap.s
2020-09-30 17:12:32 +02:00

2150 lines
63 KiB
ArmAsm

// Module Name:
// ctxswap.s
// Abstract:
// Author:
// Bernard Lint Jul-12-1995
// Environment:
// Kernel mode only
// Revision History:
#include "ksia64.h"
.file "ctxswap.s"
.text
// Globals imported:
.global KiReadySummary
.global KiIdleSummary
.global KiDispatcherReadyListHead
.global KeTickCount
.global KiMasterSequence
.global KiMasterRid
.global KiWaitInListHead
.global KiWaitOutListHead
#if !defined(NT_UP)
.global KiContextSwapLock
.global KiDispatcherLock
.global KiSwapContextNotifyRoutine
#endif // !defined(NT_UP)
PublicFunction(KiDeliverApc)
PublicFunction(KiSaveExceptionFrame)
PublicFunction(KiRestoreExceptionFrame)
PublicFunction(KiActivateWaiterQueue)
PublicFunction(KiReadyThread)
PublicFunction(KeFlushEntireTb)
PublicFunction(KiQuantumEnd)
PublicFunction(KiSyncNewRegionId)
PublicFunction(KiCheckForSoftwareInterrupt)
PublicFunction(KiSaveHigherFPVolatile)
#if DBG
PublicFunction(KeBugCheckEx)
#endif // DBG
SBTTL("Unlock Dispatcher Database")
// VOID
// KiUnlockDispatcherDatabase (
// IN KIRQL OldIrql
// )
// Routine Description:
// This routine is entered at synchronization level with the dispatcher
// database locked. Its function is to either unlock the dispatcher
// database and return or initiate a context switch if another thread
// has been selected for execution.
// N.B. A context switch CANNOT be initiated if the previous IRQL
// is greater than or equal to DISPATCH_LEVEL.
// N.B. This routine is carefully written to be a leaf function. If,
// however, a context swap should be performed, the routine is
// switched to a nested fucntion.
// Arguments:
// OldIrql (a0) - Supplies the IRQL when the dispatcher database
// lock was acquired (in low order byte, not zero extended).
// Return Value:
// None.
NESTED_ENTRY(KiUnlockDispatcherDatabase)
NESTED_SETUP(1,3,1,0)
// Register aliases
rDPC = loc2 // DPC active flag
rpT1 = t1 // temp pointer
rpT2 = t2 // temp pointer
rpT3 = t3 // temp pointer
rT1 = t5 // temp regs
rT2 = t6
rpDPLock = t7 // pointer to dispatcher lock
rPrcb = t8 // PRCB pointer
pNotNl = pt2 // true if next thread not NULL
pIRQGE = pt3 // true if DISPATCH_LEVEL <= old irql
pIRQLT = pt4 // true if DISPATCH_LEVEL > old irql
pDPC = pt5 // true if DPC active
PROLOGUE_END
// Check if a thread has been scheduled to execute on the current processor
#if !defined(NT_UP)
add rpDPLock = @gprel(KiDispatcherLock), gp
#endif // !defined(NT_UP)
movl rPrcb = KiPcr + PcPrcb
;;
LDPTR (rPrcb, rPrcb) // rPrcb -> PRCB
;;
add rpT1 = PbNextThread, rPrcb // -> next thread
add rpT2 = PbDpcRoutineActive,rPrcb // -> DPC active flag
;;
LDPTR (v0, rpT1) // v0 = next thread
;;
cmp.ne pNotNl = zero, v0 // pNotNl = next thread is 0
zxt1 a0 = a0 // isolate old IRQL
;;
(pNotNl) cmp.leu.unc pIRQGE, pIRQLT = DISPATCH_LEVEL, a0
mov rDPC = 1 // speculate that DPC is active
(pIRQLT) br.spnt KxUnlockDispatcherDatabase
;;
// Case 1:
// Next thread is NULL:
// Release dispatcher database lock, restore IRQL to its previous level
// and return
// Case 2:
// A new thread has been selected to run on the current processor, but
// the new IRQL is not below dispatch level. Release the dispatcher
// lock and restore IRQL. If the current processor is
// not executing a DPC, then request a dispatch interrupt on the current
// processor.
// At this point pNotNl = 1 if thread not NULL, 0 if NULL
(pIRQGE) ld4 rDPC = [rpT2] // rDPC.4 = DPC active flag
#if !defined(NT_UP)
RELEASE_SPINLOCK(rpDPLock) // release dispatcher lock
#endif // !defined(NT_UP)
;;
LOWER_IRQL(a0)
cmp4.eq pDPC = rDPC, zero // pDPC = request DPC intr
REQUEST_DISPATCH_INT(pDPC) // request DPC interrupt
NESTED_RETURN
NESTED_EXIT(KiUnlockDispatcherDatabase)
// N.B. This routine is carefully written as a nested function.
// Control only reaches this routine from above.
// rPrcb contains the address of PRCB
// v0 contains the next thread
NESTED_ENTRY(KxUnlockDispatcherDatabase)
PROLOGUE_BEGIN
.regstk 1, 2, 1, 0
alloc t16 = ar.pfs, 1, 2, 1, 0
.save rp, loc0
mov loc0 = brp
.fframe SwitchFrameLength
add sp = -SwitchFrameLength, sp
;;
.save ar.unat, loc1
mov loc1 = ar.unat
add t0 = ExFltS19+SwExFrame+STACK_SCRATCH_AREA, sp
add t1 = ExFltS18+SwExFrame+STACK_SCRATCH_AREA, sp
;;
.save.gf 0x0, 0xC0000
stf.spill [t0] = fs19, ExFltS17-ExFltS19
stf.spill [t1] = fs18, ExFltS16-ExFltS18
;;
.save.gf 0x0, 0x30000
stf.spill [t0] = fs17, ExFltS15-ExFltS17
stf.spill [t1] = fs16, ExFltS14-ExFltS16
mov t10 = bs4
;;
.save.gf 0x0, 0xC000
stf.spill [t0] = fs15, ExFltS13-ExFltS15
stf.spill [t1] = fs14, ExFltS12-ExFltS14
mov t11 = bs3
;;
.save.gf 0x0, 0x3000
stf.spill [t0] = fs13, ExFltS11-ExFltS13
stf.spill [t1] = fs12, ExFltS10-ExFltS12
mov t12 = bs2
;;
.save.gf 0x0, 0xC00
stf.spill [t0] = fs11, ExFltS9-ExFltS11
stf.spill [t1] = fs10, ExFltS8-ExFltS10
mov t13 = bs1
;;
.save.gf 0x0, 0x300
stf.spill [t0] = fs9, ExFltS7-ExFltS9
stf.spill [t1] = fs8, ExFltS6-ExFltS8
mov t14 = bs0
;;
.save.gf 0x0, 0xC0
stf.spill [t0] = fs7, ExFltS5-ExFltS7
stf.spill [t1] = fs6, ExFltS4-ExFltS6
mov t15 = ar.lc
;;
.save.gf 0x0, 0x30
stf.spill [t0] = fs5, ExFltS3-ExFltS5
stf.spill [t1] = fs4, ExFltS2-ExFltS4
;;
.save.f 0xC
stf.spill [t0] = fs3, ExFltS1-ExFltS3 // save fs3
stf.spill [t1] = fs2, ExFltS0-ExFltS2 // save fs2
;;
.save.f 0x3
stf.spill [t0] = fs1, ExBrS4-ExFltS1 // save fs1
stf.spill [t1] = fs0, ExBrS3-ExFltS0 // save fs0
;;
.save.b 0x18
st8 [t0] = t10, ExBrS2-ExBrS4 // save bs4
st8 [t1] = t11, ExBrS1-ExBrS3 // save bs3
;;
.save.b 0x6
st8 [t0] = t12, ExBrS0-ExBrS2 // save bs2
st8 [t1] = t13, ExIntS2-ExBrS1 // save bs1
;;
.save.b 0x1
st8 [t0] = t14, ExIntS3-ExBrS0 // save bs0
;;
.save.gf 0xC, 0x0
.mem.offset 0,0
st8.spill [t0] = s3, ExIntS1-ExIntS3 // save s3
.mem.offset 8,0
st8.spill [t1] = s2, ExIntS0-ExIntS2 // save s2
;;
.save.gf 0x3, 0x0
.mem.offset 0,0
st8.spill [t0] = s1, ExApLC-ExIntS1 // save s1
.mem.offset 8,0
st8.spill [t1] = s0, ExApEC-ExIntS0 // save s0
;;
.savepsp ar.pfs, ExceptionFrameLength-ExApEC-STACK_SCRATCH_AREA
st8 [t1] = t16, ExIntNats-ExApEC
mov t4 = ar.unat // captured Nats of s0-s3
;;
.savepsp ar.lc, ExceptionFrameLength-ExApLC-STACK_SCRATCH_AREA
st8 [t0] = t15
.savepsp @priunat, ExceptionFrameLength-ExIntNats-STACK_SCRATCH_AREA
st8 [t1] = t4 // save Nats of s0-s3
mov s0 = rPrcb
PROLOGUE_END
mov s2 = v0
movl rpT1 = KiPcr + PcCurrentThread
;;
LDPTR (s1, rpT1) // current thread
add rpT2 = PbNextThread, s0 // -> next thread
;;
add rpT3 = ThWaitIrql, s1 // -> previous IRQL
STPTRINC (rpT2, zero,PbCurrentThread-PbNextThread) // clear next thread address
;;
st1 [rpT3] = a0 // save previous IRQL
// Reready current thread for execution and swap context to the selected thread.
// N.B. The return from the call to swap context is directly to the swap
// thread exit.
STPTR (rpT2, s2) // set current thread object
mov out0 = s1 // out0 -> previous thread
br.call.sptk brp = KiReadyThread
;;
movl rT1 = KiSwapThreadExit
;;
mov brp = rT1 // set return address
br.call.sptk bt0 = SwapContext
;;
// N.B.: return to KiSwapThreadExit
NESTED_EXIT(KxUnlockDispatcherDatabase)
SBTTL("Swap Thread")
// INT_PTR
// KiSwapThread (
// VOID
// )
// Routine Description:
// This routine is called to select and the next thread to run on the
// current processor and to perform a context switch to the thread.
// Arguments:
// None.
// Return Value:
// Wait completion status (v0).
// Notes:
// GP valid on entry -- GP is not switched, just use kernel GP
NESTED_ENTRY(KiSwapThread)
PROLOGUE_BEGIN
.regstk 1, 2, 1, 0
alloc t16 = ar.pfs, 1, 2, 1, 0
.save rp, loc0
mov loc0 = brp
.fframe SwitchFrameLength
add sp = -SwitchFrameLength, sp
;;
.save ar.unat, loc1
mov loc1 = ar.unat
add t0 = ExFltS19+SwExFrame+STACK_SCRATCH_AREA, sp
add t1 = ExFltS18+SwExFrame+STACK_SCRATCH_AREA, sp
;;
.save.gf 0x0, 0xC0000
stf.spill [t0] = fs19, ExFltS17-ExFltS19
stf.spill [t1] = fs18, ExFltS16-ExFltS18
;;
.save.gf 0x0, 0x30000
stf.spill [t0] = fs17, ExFltS15-ExFltS17
stf.spill [t1] = fs16, ExFltS14-ExFltS16
mov t10 = bs4
;;
.save.gf 0x0, 0xC000
stf.spill [t0] = fs15, ExFltS13-ExFltS15
stf.spill [t1] = fs14, ExFltS12-ExFltS14
mov t11 = bs3
;;
.save.gf 0x0, 0x3000
stf.spill [t0] = fs13, ExFltS11-ExFltS13
stf.spill [t1] = fs12, ExFltS10-ExFltS12
mov t12 = bs2
;;
.save.gf 0x0, 0xC00
stf.spill [t0] = fs11, ExFltS9-ExFltS11
stf.spill [t1] = fs10, ExFltS8-ExFltS10
mov t13 = bs1
;;
.save.gf 0x0, 0x300
stf.spill [t0] = fs9, ExFltS7-ExFltS9
stf.spill [t1] = fs8, ExFltS6-ExFltS8
mov t14 = bs0
;;
.save.gf 0x0, 0xC0
stf.spill [t0] = fs7, ExFltS5-ExFltS7
stf.spill [t1] = fs6, ExFltS4-ExFltS6
mov t15 = ar.lc
;;
.save.gf 0x0, 0x30
stf.spill [t0] = fs5, ExFltS3-ExFltS5
stf.spill [t1] = fs4, ExFltS2-ExFltS4
;;
.save.f 0xC
stf.spill [t0] = fs3, ExFltS1-ExFltS3 // save fs3
stf.spill [t1] = fs2, ExFltS0-ExFltS2 // save fs2
;;
.save.f 0x3
stf.spill [t0] = fs1, ExBrS4-ExFltS1 // save fs1
stf.spill [t1] = fs0, ExBrS3-ExFltS0 // save fs0
;;
.save.b 0x18
st8 [t0] = t10, ExBrS2-ExBrS4 // save bs4
st8 [t1] = t11, ExBrS1-ExBrS3 // save bs3
;;
.save.b 0x6
st8 [t0] = t12, ExBrS0-ExBrS2 // save bs2
st8 [t1] = t13, ExIntS2-ExBrS1 // save bs1
;;
.save.b 0x1
st8 [t0] = t14, ExIntS3-ExBrS0 // save bs0
;;
.save.gf 0xC, 0x0
.mem.offset 0,0
st8.spill [t0] = s3, ExIntS1-ExIntS3 // save s3
.mem.offset 8,0
st8.spill [t1] = s2, ExIntS0-ExIntS2 // save s2
;;
.save.gf 0x3, 0x0
.mem.offset 0,0
st8.spill [t0] = s1, ExApLC-ExIntS1 // save s1
.mem.offset 8,0
st8.spill [t1] = s0, ExApEC-ExIntS0 // save s0
;;
.savepsp ar.pfs, ExceptionFrameLength-ExApEC-STACK_SCRATCH_AREA
st8 [t1] = t16, ExIntNats-ExApEC
mov t4 = ar.unat // captured Nats of s0-s3
;;
.savepsp ar.lc, ExceptionFrameLength-ExApLC-STACK_SCRATCH_AREA
st8 [t0] = t15
.savepsp @priunat, ExceptionFrameLength-ExIntNats-STACK_SCRATCH_AREA
st8 [t1] = t4 // save Nats of s0-s3
PROLOGUE_END
// Register aliases
// s0 // Prcb address
// s1 // old thread address
// s2 // new thread address
rRdySum = s3 // ready summary
rWstatus = s3 // wait status
rpT1 = t0 // temp pointer
rpT2 = t1 // temp pointer
rProcNum = t2 // processor number
rIdleSum = t3 // idle summary
rpRdyHead = t4 // -> ready list head
rQEntry = t5 // queue entry
rQueNum = t6 // ready queue number
rFlink = t7 // forward link
rBlink = t8 // backward link
rFirstByte = t9 // first non-zero byte
rT1 = t10 // temp regs
rRdyShftd = t11 // current shifted ready summary bits
rT3 = t12 // temp regs
rT4 = t13
rpRdySum = t14 // pointer to KiReadySummary
rAffmask = t15 // processor affinity mask
#if !defined(NT_UP)
rTickCount = t16 // tick count
rThIdealProc = t17 // thread ideal processor
rThWaitTime = t18 // time of thread ready
rThNextProc = t19 // thread's last good processor
rTrialEntry = t20 // next candidate entry in wait list
rTrialThrd = t21 // next candidate thread in wait list
#endif // !defiend(NT_UP)
pNotNl = pt0 // not null predicate
pEmpty = pt1 // ready list empty
pNoAPC = pt2 // do not dispatch APC
pRdy = pt3 // test next ready queue
pNoRdy = pt4 // no more ready queues
pEq = pt5 // if cmp.eq is true
pNotEq = pt6 // if cmp.eq is not true
pMt1 = pt7 // if match
pMt2 = pt8 // if match
add rpRdySum = @gprel(KiReadySummary), gp // rpRdysum -> KiReadySummary
movl rpT1 = KiPcr + PcPrcb
;;
LDPTRINC (s0, rpT1, PcCurrentThread-PcPrcb) // -> prcb
ld4 rRdySum = [rpRdySum] // rRdysum.4 = KiReadySummary
;;
add rpT2 = PbNextThread, s0
LDPTRINC (s1, rpT1, PcSetMember-PcCurrentThread) // current thread
;;
LDPTR (s2, rpT2) // s2 -> new thread
STPTR (rpT2, zero) // zero next thread
;;
#if !defined(NT_UP)
ld4 rAffmask = [rpT1], PcNumber-PcSetMember // rAffmask.4 = processor affinity mask
;;
ld1 rProcNum = [rpT1] // processor number
#endif // !defined(NT_UP)
cmp.ne pNotNl = zero, s2 // if ne, next thread selected
(pNotNl) br.sptk Kst_SwapContext // br if thread not null
// Search KiReadySummary to find highest priority queue with at least one
// thread ready to run
pcmp1.eq rT1 = rRdySum, zero // parallel cmp to zero
;;
czx1.l rFirstByte = rT1 // index of byte with first one
;;
add rFirstByte = -4, rFirstByte // adjust for 32-bit value
;;
shl rQueNum = rFirstByte, 3 // shift for bit index
;;
shl rRdyShftd = rRdySum, rQueNum // shift first byte to MSB
sub rQueNum = 31, rQueNum // change bit index to queue #
;;
Kst_Loop:
cmp.gt pNoRdy = 0, rQueNum // Check for last queue (0)
(pNoRdy) br.sptk Kst_NoRdy // br if no more queues to check
;;
tbit.nz pRdy = rRdyShftd, 31 // test high order bit
(pRdy) br.sptk Kst_Ready // br if find queue not empty
;;
// If the next bit is set in the ready summary, then scan the corresponding
// dispatcher ready queue.
Kst50:
sub rQueNum = rQueNum, zero, 1 // decrement queue #
shl rRdyShftd = rRdyShftd, 1 // get next bit
br.sptk Kst_Loop // check next queue
;;
// All ready queues were scanned without finding a runnable thread so
// default to the idle thread and set the appropriate bit in idle summary.
Kst_NoRdy:
#if defined(_COLLECT_SWITCH_DATA_)
add rpT1 = @gprel(KeThreadSwitchCounters), gp
;;
add rpT1 = TwSwitchToIdle, rpT1
;;
ld4 rT1 = [rpT1]
;;
add rT1 = rT1, zero, 1 // increment count
;;
st4 [rpT1] = rT1
#endif // defined(_COLLECT_SWITCH_DATA_)
add rpT1 = @gprel(KiIdleSummary), gp // -> idle summary
add rpT2 = PbIdleThread, s0 // -> PbIdleThread
;;
#if defined(NT_UP)
mov rIdleSum = 1 // get current idle summary
#else
ld4 rIdleSum= [rpT1] // get current idle summary
;;
or rIdleSum = rIdleSum, rAffmask // set member bit in idle summary
#endif // !defined(NT_UP)
;;
st4 [rpT1] = rIdleSum // set new idle summary
LDPTR (s2, rpT2) // address of idle thread
br.sptk Kst_SwapContext // branch to do swap context
// If the thread can execute on the current processor, then remove it from
// the dispatcher ready queue. At this point rQueNum has number of highest
// priority non-empty queue.
Kst_Ready:
add rpRdyHead = @gprel(KiDispatcherReadyListHead),gp // get ready list head base address
;;
#ifdef _WIN64
shladd rpRdyHead=rQueNum,4,rpRdyHead // compute ready queue address
#else
shladd rpRdyHead=rQueNum,3,rpRdyHead // compute ready queue address
#endif
;;
add rpT1 = LsFlink, rpRdyHead // -> addr of first queue entry
;;
LDPTR (rQEntry,rpT1) // rQEntry.4 = address of first queue entry
;;
Kst70:
add s2 = -ThWaitListEntry, rQEntry // -> thread object
;;
#if !defined(NT_UP)
// If the thread can execute on the current processor, then remove it from
// the dispatcher ready queue.
add rpT1 = ThAffinity, s2
;;
ld4 rT3 = [rpT1] // rT3 = ThAffinity
;;
and rT1 = rAffmask, rT3 // the current processor?
;;
cmp4.ne pt0 = zero, rT1 // if ne, thread affinity compatible
add rQEntry = LsFlink, rQEntry // t4 -> LsFlink(rQEntry)
(pt0) br.cond.sptk Kst80
;;
LDPTR (rQEntry, rQEntry) // get address of next entry
;;
cmp.ne pt0 = rQEntry, rpRdyHead // check for end of list
(pt0) br.cond.sptk Kst70 // if ne, not end of list
br Kst50
;;
// If the thread last ran on the current processor, the processor is the
// ideal processor for the thread, the thread has been waiting for longer
// than a quantum, ot its priority is greater than (or equal) low realtime plus 9,
// then select the thread. Otherwise, an attempt is made to find a more
// appropriate candidate.
Kst80:
add rpT1 = ThNextProcessor, s2
add rpT2 = ThIdealProcessor, s2
;;
ld1 rThNextProc = [rpT1]
ld1 rThIdealProc = [rpT2]
;;
add rpT1 = ThWaitTime-ThNextProcessor, rpT1
add rpT2 = @gprel(KeTickCount),gp // -> KeTickCount
;;
ld4 rThWaitTime = [rpT1] // get time of thread ready
// ld4 or ld8???
ld4 rTickCount = [rpT2] // rTickCount = KeTickCount
cmp.eq pMt1 = rThNextProc, rProcNum // check last processor
(pMt1) br.cond.spnt Kst120 // if eq, last processor match
;;
sub rT1 = rTickCount, rThWaitTime // rT1 = TickCount-WaitTime
cmp.eq pMt2= rThIdealProc,rProcNum // check ideal processor
(pMt2) br.cond.spnt Kst120 // if eq ideal processor match
;;
cmp.leu pMt1 = LOW_REALTIME_PRIORITY+9, rQueNum // choose thread if LOW+9 <= priority
cmp.leu pMt2 = READY_SKIP_QUANTUM+1, rT1 // choose thread if QUANT+1 <= time delta
add rpT1 = LsFlink, rQEntry
(pMt1) br.cond.spnt Kst120
(pMt2) br.cond.spnt Kst120
;;
// search forward in the ready queue until the end of the list is reached
// or a more appropriate thread is found
Kst90:
LDPTR (rTrialEntry, rpT1) // get address of next entry
;;
cmp.eq pEq= rTrialEntry,rpRdyHead // if eq, at end of list
(pEq) br.spnt Kst120 // select original thread
;;
add rTrialThrd = -ThWaitListEntry, rTrialEntry // compute address of new thread object
;;
add rpT1= ThAffinity,rTrialThrd // address of affinity
add rpT2= ThWaitTime,rTrialThrd // address of WaitTime
;;
ld4 rT3 = [rpT1], ThNextProcessor-ThAffinity
;;
and rT1 = rAffmask, rT3 // the current processor?
;;
cmp4.eq pEq = zero, rT1 // if eq, thread affinity not compatible
;;
(pEq) br.cond.spnt Kst100 // br if not compatible
;;
ld1 rThNextProc = [rpT1]
;;
cmp.eq pMt1 = rThNextProc,rProcNum // check processor match
;;
(pMt1) br.cond.spnt Kst110 // if eq, processor match
;;
add rpT1 = ThIdealProcessor-ThNextProcessor, rpT1
;;
ld1 rThIdealProc = [rpT1]
;;
cmp.eq pMt2 = rThIdealProc,rProcNum // check ideal processor
;;
(pMt2) br.cond.spnt Kst110 // if eq, ideal processor match
;;
Kst100:
ld4 rThWaitTime = [rpT2] // get time of thread ready
;;
sub rT1 = rTickCount,rThWaitTime // rT1 = TickCount-WaitTime
;;
cmp.leu pMt1 = READY_SKIP_QUANTUM+1, rT1 // choose original thread if QUANT+1 <= time delta
(pMt1) br.cond.spnt Kst120
;;
add rpT1 = LsFlink, rTrialEntry // get address of Flink
br.sptk Kst90
;;
Kst110:
mov rQEntry = rTrialEntry // set list entry address
mov s2 = rTrialThrd // set new thread address
;;
// rProcNum = current processor and processor for new thread
Kst120:
#if defined(_COLLECT_SWITCH_DATA_)
add rpT1 = @gprel(KeThreadSwitchCounters), gp
cmp.eq pt0, pt1 = rThNextProc, rProcNum // if eq, last processor match
;;
add rpT1 = TwFindAny, rpT1 // computer address of Any counter
(pt1) cmp.eq.unc pt2 = rThIdealProc,rProcNum // if eq, ideal processor match
;;
(pt0) add rpT2 = TwFindLast-TwFindAny, rpT1 // address of Last counter
(pt2) add rpT2 = TwFindIdeal-TwFindAny, rpT1 // address of Ideal counter
;;
ld4 rT4 = [rpT2] // get appropriate counter
;;
add rT4 = 1, rT4 // increment counter
;;
st4 [rpT2] = rT4 // store counter
#endif // defined(_COLLECT_SWITCH_DATA_)
add rpT1 = ThNextProcessor, s2
;;
st1 [rpT1] = rProcNum // update next processor
;;
#endif // !defined(NT_UP)
// Remove the selected thread from the ready queue.
add rpT1 = LsFlink, rQEntry // rpT1 -> forward link
add rpT2 = LsBlink, rQEntry // rpT2 -> backward link
;;
LDPTR (rFlink, rpT1) // rFlink = forward link
LDPTR (rBlink, rpT2) // rBlink = backward link
;;
add rpT1 = LsFlink, rBlink // rpT1 -> previous entry
add rpT2 = LsBlink, rFlink // rpT2 -> next entry
;;
STPTR (rpT1, rFlink) // set forward link in previous entry
STPTR (rpT2, rBlink) // set backward link in next entry
mov rT1 = 1 // set bit for mask generation
cmp.eq pEmpty = rFlink, rBlink // if eq, list is empty
;;
(pEmpty) shl rT1 = rT1, rQueNum // ready summary set member
;;
(pEmpty) xor rT1 = rT1, rRdySum // clear ready summary bit
;;
(pEmpty) st4 [rpRdySum] = rT1 // store updated KiReadySummary
// Swap context to the next thread.
Kst_SwapContext:
add rpT1 = PbCurrentThread, s0
;;
STPTR (rpT1, s2) // set addr of current thread
br.call.sptk brp = SwapContext // call SwapContext(prcb, OldTh, NewTh)
;;
// Lower IRQL, deallocate exception/switch frame, and return wait completion status.
// N.B. SwapContext releases the dispatcher database lock.
// N.B. v0 contains the kernel APC pending state on return.
// N.B. s2 contains the address of the new thread on return.
ALTERNATE_ENTRY(KiSwapThreadExit)
add rpT1 = ThWaitStatus, s2 // -> ThWaitStatus
add rpT2 = ThWaitIrql, s2 // -> ThWaitIrql
zxt1 v0 = v0
;;
LDPTR (rWstatus, rpT1) // wait completion status
ld1 a0 = [rpT2] // a0 = original wait IRQL
;;
or rT1 = a0, v0
;;
cmp.eq pNoAPC = zero, rT1 // APC pending and IRQL == 0
add rpT2 = PbApcBypassCount, s0
(pNoAPC) br.spnt Kst_Exit
;;
.regstk 1, 2, 3, 0
alloc t16 = ar.pfs, 1, 2, 3, 0
SET_IRQL(APC_LEVEL)
movl rpT1 = KiPcr+PcApcInterrupt
;;
ld4 rT1 = [rpT2]
st1 [rpT1] = zero
mov out0 = KernelMode
;;
add rT1 = 1, rT1
mov out1 = zero
mov out2 = zero
;;
st4 [rpT2] = rT1
br.call.sptk brp = KiDeliverApc
;;
// Lower IRQL to wait level, set return status, restore registers, and
// return.
Kst_Exit:
LOWER_IRQL(a0) // a0 = new irql
add out0 = STACK_SCRATCH_AREA+SwExFrame, sp
mov v0 = rWstatus // return wait status
br.call.sptk brp = KiRestoreExceptionFrame
;;
add rpT1 = ExApEC+SwExFrame+STACK_SCRATCH_AREA, sp
;;
ld8 rT1 = [rpT1]
mov brp = loc0
;;
mov ar.unat = loc1
nop.f 0
mov ar.pfs = rT1
.restore
add sp = SwitchFrameLength, sp
nop.i 0
br.ret.sptk brp
;;
NESTED_EXIT(KiSwapThread)
SBTTL("Swap Context to Next Thread")
// Routine:
// SwapContext
// Routine Description:
// This routine is called to swap context from one thread to the next.
// Arguments:
// s0 - Address of Processor Control Block (PRCB).
// s1 - Address of previous thread object.
// s2 - Address of next thread object.
// Return value:
// v0 - Kernel APC pending flag
// s0 - Address of Processor Control Block (PRCB).
// s1 - Address of previous thread object.
// s2 - Address of current thread object.
// Note:
// Kernel GP is not saved and restored across context switch
NESTED_ENTRY(SwapContext)
// Register aliases
rT1 = t1 // temp
rT2 = t2 // temp
rT3 = t3 // temp
rNewproc = t4 // next process object
rOldproc = t5 // previous process object
rpThBSL = t6 // pointer to new thread backing store limit
rpT1 = t7 // temp pointer
rpT2 = t8 // temp pointer
rpT3 = t9 // temp pointer
rRSEDis = t10 // RSE disable
rNewIKS = t11 // new initial kernel stack
rRSEEn = t12 // RSE enable
rNewKSL = t13 // new kernel stack limit
rpPcrBSL = t14 // pointer to new kernel backing store limit
rpNewBSP = t15 // pointer to new thread BSP
rpNewRNAT = t16 // pointer to new thread RNAT
rNewBSP = t17 // new thread BSP/BSPSTORE
rOldBSP = t18 // old thread BSP
rOldRNAT = t19 // old thread RNAT
rNewRNAT = t20 // new thread RNAT
rOldIKS = t21 // old thread initial kstack
rOldPsrL = s3 // old psr interrupt flag
pApc = pt3 // APC pending
pUsTh = pt4 // is user thread?
pKrTh = pt5 // is user thread?
pIdle = pt6 // true if SwapContext not called from Idle
pSave = pt7 // is high fp set dirty?
pDiff = ps1 // if new and old process different
pSame = ps2 // if new and old process same
// Set new thread's state to running. Note this must be done
// under the dispatcher lock so that KiSetPriorityThread sees
// the correct state.
PROLOGUE_BEGIN
alloc rT2 = ar.pfs, 0, 0, 2, 0
add rpT1 = SwRp+STACK_SCRATCH_AREA, sp
add rpT2 = SwPFS+STACK_SCRATCH_AREA, sp
;;
mov rOldBSP = ar.bsp
mov rT1 = brp
add rpT3 = ThState, s2
;;
.savesp brp, SwRp+STACK_SCRATCH_AREA
st8.nta [rpT1] = rT1, SwFPSR-SwRp // save return link
.savesp ar.pfs, SwPFS+STACK_SCRATCH_AREA
st8.nta [rpT2] = rT2, SwPreds-SwPFS // save pfs
mov rT3 = Running
;;
flushrs
st1.nta [rpT3] = rT3
mov rT1 = pr
cmp.ne pUsTh = zero, teb
;;
mov ar.rsc = r0 // disable RSE
mov out0 = ar.fpsr
add rpT3 = ThStackBase, s1
;;
LDPTR (rT3, rpT3)
st8 [rpT1] = out0 // save kernel FPSR
st8 [rpT2] = rT1 // save preserved predicates
;;
(pUsTh) mov rT1 = ar21
(pUsTh) mov rT2 = ar24
;;
(pUsTh) add rpT1 = -ThreadStateSaveAreaLength+TsAppRegisters+TsAr21, rT3
(pUsTh) add rpT2 = -ThreadStateSaveAreaLength+TsAppRegisters+TsAr24, rT3
;;
(pUsTh) st8 [rpT1] = rT1, TsAr25-TsAr21
(pUsTh) st8 [rpT2] = rT2, TsAr26-TsAr24
(pUsTh) mov rT1 = ar25
(pUsTh) mov rT2 = ar26
;;
(pUsTh) st8 [rpT1] = rT1, TsAr27-TsAr25
(pUsTh) st8 [rpT2] = rT2, TsAr28-TsAr26
(pUsTh) mov rT1 = ar27
(pUsTh) mov rT2 = ar28
;;
(pUsTh) st8 [rpT1] = rT1, TsAr29-TsAr27
(pUsTh) st8 [rpT2] = rT2, TsAr30-TsAr28
(pUsTh) mov rT1 = ar29
(pUsTh) mov rT2 = ar30
;;
(pUsTh) st8 [rpT1] = rT1
(pUsTh) st8 [rpT2] = rT2
add rpT3 = ThInitialStack, s1
;;
LDPTRINC (rOldIKS, rpT3, ThKernelBStore-ThInitialStack)
mov rOldRNAT = ar.rnat
mov rT2 = psr
;;
st8.nta [rpT3] = rOldBSP
tbit.nz pSave = rT2, PSR_MFH // check mfh bit
add rpT2 = SwBsp+STACK_SCRATCH_AREA, sp
;;
st8.nta [rpT2] = rOldBSP, SwRnat-SwBsp
(pSave) add rpT1 = -ThreadStateSaveAreaLength-TrapFrameLength+TrStIPSR, rOldIKS
;;
(pSave) ld8.nta rT2 = [rpT1]
st8.nta [rpT2] = rOldRNAT
;;
(pSave) dep rT2 = 0, rT2, PSR_MFH, 1 // Clear user trap frame mfh bit
;;
(pSave) st8.nta [rpT1] = rT2
(pSave) add out0 = -TrStIPSR+TrapFrameLength+TsHigherFPVolatile, rpT1
(pSave) br.call.sptk brp = KiSaveHigherFPVolatile
;;
// Acquire the context swap lock so the address space of the old process
// cannot be deleted and then release the dispatcher database lock.
// N.B. This lock is used to protect the address space until the context
// switch has sufficiently progressed to the point where the address
// space is no longer needed. This lock is also acquired by the reaper
// thread before it finishes thread termination.
#if !defined(NT_UP)
add rpT1 = @gprel(KiContextSwapLock), gp
add rpT2 = @gprel(KiDispatcherLock), gp
add rpT3 = @gprel(KiSwapContextNotifyRoutine), gp
;;
ld8 rpT3 = [rpT3]
ACQUIRE_SPINLOCK(rpT1, s1, Sc_Lock1)
// Release KiDispatcherLock after setting thread state to Running
RELEASE_SPINLOCK(rpT2)
add rpT1 = EtCid+CidUniqueThread, s1 // -> old thread unique id
add rpT2 = EtCid+CidUniqueThread, s2 // -> new thread unique id
;;
ld8.nta out0 = [rpT1]
ld8.nta out1 = [rpT2]
cmp.ne pt1 = zero, rpT3
;;
(pt1) ld8.nta rT1 = [rpT3], 8
;;
(pt1) ld8.nta gp = [rpT3]
mov bt0 = rT1
(pt1) br.call.spnt brp = bt0 // call notify routine
;;
movl gp = _gp
#endif // !defined(NT_UP)
PROLOGUE_END
// ***** TBD ****** Save preformance counters? (user vs. kernel)
// Accumlate the total time spent in a thread.
#if defined(PERF_DATA)
**** TBD **** MIPS code
addu a0,sp,ExFltF20 // compute address of result
move a1,zero // set address of optional frequency
jal KeQueryPerformanceCounter // query performance counter
lw t0,ExFltF20(sp) // get current cycle count
lw t1,ExFltF20 + 4(sp) //
lw t2,PbStartCount(s0) // get starting cycle count
lw t3,PbStartCount + 4(s0) //
sw t0,PbStartCount(s0) // set starting cycle count
sw t1,PbStartCount + 4(s0) //
lw t4,EtPerformanceCountLow(s1) // get accumulated cycle count
lw t5,EtPerformanceCountHigh(s1) //
subu t6,t0,t2 // subtract low parts
subu t7,t1,t3 // subtract high parts
sltu v0,t0,t2 // generate borrow from high part
subu t7,t7,v0 // subtract borrow
addu t6,t6,t4 // add low parts
addu t7,t7,t5 // add high parts
sltu v0,t6,t4 // generate carry into high part
addu t7,t7,v0 // add carry
sw t6,EtPerformanceCountLow(s1) // set accumulated cycle count
sw t7,EtPerformanceCountHigh(s1) //
#endif // defined(PERF_DATA)
// The following entry point is used to switch from the idle thread to
// another thread.
;;
ALTERNATE_ENTRY(SwapFromIdle)
// Get address of old and new process objects.
alloc rT1 = ar.pfs, 2, 0, 1, 0
add rpT2 = ThApcState+AsProcess,s2 // -> new thread AsProcess
add rpT1 = ThApcState+AsProcess,s1 // -> old thread AsProcess
;;
LDPTR (rOldproc, rpT1) // old process
LDPTR (rNewproc, rpT2) // new process
;;
flushrs
add rpT1 = ThInitialStack, s2
add rpT2 = ThKernelStack, s1
DISABLE_INTERRUPTS(rOldPsrL)
;;
mov ar.rsc = r0 // disable RSE
// Store the kernel stack pointer in the previous thread object,
// load the new kernel stack pointer from the new thread object,
// switch basking store pointers, select new process id and swap
// to the new process.
LDPTRINC (rNewIKS, rpT1, ThKernelStack-ThInitialStack)
STPTR (rpT2, sp) // save current sp
;;
LDPTRINC (sp, rpT1, ThStackLimit-ThKernelStack) // new kernel stack
movl rpT2 = KiPcr + PcInitialStack
;;
LDPTR (rNewKSL, rpT1) // new stack limit
st8 [rpT2] = rNewIKS, PcStackLimit-PcInitialStack
;;
st8 [rpT2] = rNewKSL
add rpNewBSP = SwBsp+STACK_SCRATCH_AREA, sp
add rpNewRNAT = SwRnat+STACK_SCRATCH_AREA, sp
;;
LDPTR (rNewBSP, rpNewBSP) // get new BSP/RNAT
ld8 rNewRNAT = [rpNewRNAT]
;;
alloc rT1 = 0,0,0,0 // make current frame 0 size
invala
;;
// Setup PCR intial kernel BSP and BSTORE limit
loadrs // invalidate RSE and ALAT
movl rpT2 = KiPcr + PcInitialBStore // -> PCR initial BSP
;;
mov ar.bspstore = rNewBSP // load new bspstore
add rpT1 = ThInitialBStore,s2 // -> new initial BSP
add rpThBSL = ThBStoreLimit,s2 // -> new bstore limit
;;
mov ar.rnat = rNewRNAT // load new RNATs
LDPTR (rT1, rpT1) // rT2 = new initial kernel BSP
;;
LDPTR (rT2, rpThBSL) // rT1 = new kernel BStore limit
st8 [rpT2] = rT1, PcBStoreLimit-PcInitialBStore // save in PCR
;;
mov ar.rsc = RSC_KERNEL // enable RSE
st8 [rpT2] = rT2 // save in PCR
;;
// If the new process is not the same as the old process, then swap the
// address space to the new process.
// N.B. The dispatcher lock cannot be dropped until all references to the
// old process address space are complete. This includes any possible
// TB Misses that could occur referencing the new address space while
// still executing in the old address space.
// N.B. The process address space swap is executed with interrupts disabled.
alloc rT1 = 0,1,2,0
cmp.ne pDiff,pSame=rOldproc,rNewproc // if ne, switch process
;;
mov out0 = rNewproc // set address of new process
mov out1 = rOldproc // set address of old process
(pDiff) br.call.sptk brp = KxSwapProcess // call swap address space(NewProc, OldProc)
;;
// In new address space, if changed.
#if !defined(NT_UP)
// Release the context swap lock
// N.B. KiContextSwapLock is always released in KxSwapProcess, if called
(pSame) add rpT1 = @gprel(KiContextSwapLock), gp
;;
PRELEASE_SPINLOCK(pSame, rpT1)
#endif // !defined(NT_UP)
// ***** TBD ***** if process swap -- save/restore debug regs?
// Update TEB
add rpT1 = ThTeb, s2 // -> new Teb
movl rpT2 = KiPcr+PcInitialStack
;;
LDPTR (teb, rpT1)
LDPTRINC (rT1, rpT2, PcCurrentThread-PcInitialStack)
;;
// ** TBD *** Restore performance counters (user vs. kernel, #, in use flag)
// Exception frame or thead object
mov kteb = teb // update kernel TEB
STPTRINC (rpT2, s2, PcInitialStack-PcCurrentThread)
cmp.ne pUsTh = zero, teb
RESTORE_INTERRUPTS(rOldPsrL)
add rpT1 = -ThreadStateSaveAreaLength-TrapFrameLength+TrStIPSR,rT1
add loc0 = ThApcState+AsKernelApcPending, s2
;;
// If the new thread has a kernel mode APC pending, then request an APC
// interrupt.
(pUsTh) ld8 rT1 = [rpT1]
ld1 loc0 = [loc0] // load the ApcPending flag
;;
(pUsTh) dep rT1 = 1, rT1, PSR_DFH, 1
;;
(pUsTh) st8 [rpT1] = rT1
cmp4.ne pApc = zero, loc0
REQUEST_APC_INT(pApc) // request APC, if pending
// Increment context switch counters
add rpT1 = PbContextSwitches, s0
add rpT2 = ThContextSwitches, s2
add rpT3 = PbIdleThread, s0 // -> IdleThread address
;;
ld4 rT1 = [rpT1]
ld4 rT2 = [rpT2]
LDPTR (rT3, rpT3)
;;
add rT1 = rT1, zero, 1
add rT2 = rT2, zero, 1
;;
st4 [rpT1] = rT1 // increment # of context switches
add rpT3 = ThStackBase, s2
st4 [rpT2] = rT2 // increment # of context switches
cmp.eq pIdle = s2, rT3 // is new thread idle thread?
(pt1) br.spnt Sc20
;;
ld8.nta rT3 = [rpT3]
cmp.ne pUsTh, pKrTh = zero, teb
(pKrTh) br.spnt Sc20
;;
(pUsTh) add rpT1 = -ThreadStateSaveAreaLength+TsAppRegisters+TsAr21, rT3
(pUsTh) add rpT2 = -ThreadStateSaveAreaLength+TsAppRegisters+TsAr24, rT3
;;
(pUsTh) ld8.nta rT1 = [rpT1], TsAr25-TsAr21
(pUsTh) ld8.nta rT2 = [rpT2], TsAr26-TsAr24
;;
(pUsTh) mov ar21 = rT1
(pUsTh) mov ar24 = rT2
(pUsTh) ld8.nta rT1 = [rpT1], TsAr27-TsAr25
(pUsTh) ld8.nta rT2 = [rpT2], TsAr28-TsAr26
;;
(pUsTh) mov ar25 = rT1
(pUsTh) mov ar26 = rT2
(pUsTh) ld8.nta rT1 = [rpT1], TsAr29-TsAr27
(pUsTh) ld8.nta rT2 = [rpT2], TsAr30-TsAr28
;;
(pUsTh) mov ar27 = rT1
(pUsTh) mov ar28 = rT2
(pUsTh) ld8.nta rT1 = [rpT1]
(pUsTh) ld8.nta rT2 = [rpT2]
;;
(pUsTh) mov ar29 = rT1
(pUsTh) mov ar30 = rT2
Sc20:
add rpT1 = SwRp+STACK_SCRATCH_AREA, sp
add rpT2 = SwPFS+STACK_SCRATCH_AREA, sp
;;
ld8 out0 = [rpT1],SwFPSR-SwRp // restore brp and pfs
ld8 out1 = [rpT2],SwPreds-SwPFS
;;
ld8 rT3 = [rpT1]
ld8 rT2 = [rpT2]
;;
// Temporary Serialize and synchronize at the end of task switch for
// taking care of KeFlushIoBuffer
sync.i
;;
srlz.i
;;
// Note: at this point s0 = Prcb, s1 = previous thread, s2 = current thread
mov ar.fpsr = rT3
mov pr = rT2 // Restore preserved preds
mov brp = out0
mov v0 = loc0 // set v0 = apc pending
mov ar.pfs = out1
br.ret.sptk brp
NESTED_EXIT(SwapContext)
SBTTL("Swap Process")
// VOID
// KiSwapProcess (
// IN PKPROCESS NewProcess,
// IN PKPROCESS OldProcess
// )
// Routine Description:
// This function swaps the address space from one process to antoher by
// assigning a new region id, if necessary, and loading the fixed entry
// in the TB that maps the process page directory page. This routine follows
// the PowerPC design for handling RID wrap.
// On entry:
// Interrupt state unknown.
// Arguments:
// NewProcess (a0) - Supplies a pointer to a control object of type process
// which represents the new process that is switched to (32-bit address).
// OldProcess (a1) - Supplies a pointer to a control object of type process
// which represents the old process that is switched from (32-bit address).
// Return Value:
// None.
NESTED_ENTRY(KiSwapProcess)
NESTED_SETUP(2,3,3,0)
PROLOGUE_END
// Register aliases
rNewProc = a0
rOldProc = a1
rpCSLock = loc2
rpT1 = t0
rpT2 = t1
rProcSet = t2
rNewActive= t3
rOldActive= t4
rMasterSeq= t5
rNewSeq = t6
rOldPsrL = t7
rVa = t8
rPDE0 = t9 // PDE for page directory page 0
rVa2 = t10
rSessionBase = t11
rSessionInfo = t12
rT1 = t13
rT2 = t14
// KiSwapProcess must get the context swap lock
// KxSwapProcess is called from SwapContext with the lock held
#if !defined(NT_UP)
add rpCSLock = @gprel(KiContextSwapLock), gp
;;
ACQUIRE_SPINLOCK(rpCSLock, rpCSLock, Ksp_Lock1)
br.sptk Ksp_Continue
#endif // !defined(NT_UP)
;;
ALTERNATE_ENTRY(KxSwapProcess)
NESTED_SETUP(2,3,3,0)
#if !defined(NT_UP)
add rpCSLock = @gprel(KiContextSwapLock), gp
#endif // !defined(NT_UP)
PROLOGUE_END
// Clear the processor set member number in the old process and set the
// processor member number in the new process.
Ksp_Continue:
ARGPTR (rNewProc)
ARGPTR (rOldProc)
#if !defined(NT_UP)
add rpT2 = PrActiveProcessors, rOldProc // -> old active processor set
movl rpT1 = KiPcr + PcSetMember // -> processor set member
;;
ld4 rProcSet= [rpT1] // rProcSet.4 = processor set member
add rpT1 = PrActiveProcessors, rNewProc // -> new active processor set
;;
ld4 rNewActive = [rpT1] // rNewActive.4 = new active processor set
ld4 rOldActive = [rpT2] // rOldActive.4 = old active processor set
;;
or rNewActive = rNewActive,rProcSet // set processor member in new set
xor rOldActive = rOldActive,rProcSet // clear processor member in old set
;;
st4 [rpT1] = rNewActive // set new active processor set
st4 [rpT2] = rOldActive // set old active processor set
#endif // !defined(NT_UP)
// If the process sequence number matches the system sequence number, then
// use the process RID. Otherwise, allocate a new process RID.
// N.B. KiMasterRid, KiMasterSequence are changed only when holding the
// KiContextSwapLock.
add rT2 = PrSessionMapInfo, rNewProc
add out0 = PrProcessRegion, rNewProc
;;
ld8 out1 = [rT2]
add rT1 = PrSessionRegion, rNewProc
;;
cmp.eq pt0 = out1, r0
;;
(pt0) st8 [rT2] = rT1
(pt0) mov out1 = rT1
br.call.sptk brp = KiSyncNewRegionId
#if !defined(NT_UP)
// Can now release the context swap lock
RELEASE_SPINLOCK(rpCSLock)
#endif // !defined(NT_UP)
// Switch address space to new process
// v0 = rRid = new process rid
fwb // hint to flush write buffers
DISABLE_INTERRUPTS(rOldPsrL)
add rpT1 = PrDirectoryTableBase, rNewProc
add rpT2 = PrSessionParentBase, rNewProc
;;
ld8.nta rPDE0 = [rpT1] // rPDE0 = Page directory page 0
ld8.nta rSessionBase = [rpT2]
;;
// To access IFA, ITDR registers, PSR.ic bit must be 0. Otherwise,
// it causes an illegal operation fault. While PSR.ic=0, any
// interruption can not be afforded. Make sure there will be no
// TLB miss and no interrupt coming in during this period.
rsm 1 << PSR_IC // PSR.ic=0
;;
srlz.d // must serialize
mov rT1 = PAGE_SHIFT << IDTR_PS // load page size field for IDTR
;;
mov cr.itir = rT1 // set up IDTR for dirbase
movl rVa = PDE_UTBASE // load vaddr for parent dirtable
;;
mov cr.ifa = rVa // set up IFA for dirbase vaddr
mov rT2 = DTR_UTBASE_INDEX
;;
itr.d dtr[rT2] = rPDE0 // insert PDE0 to DTR
movl rVa = PDE_STBASE
;;
mov cr.ifa = rVa
mov rT2 = DTR_STBASE_INDEX
;;
itr.d dtr[rT2] = rSessionBase // insert the root for session space
;;
ssm 1 << PSR_IC // PSR.ic=1
;;
srlz.i // must I serialize
;;
RESTORE_INTERRUPTS(rOldPsrL) // restore PSR.i
NESTED_RETURN
NESTED_EXIT(KiSwapProcess)
SBTTL("Retire Deferred Procedure Call List")
// Routine:
// VOID
// KiRetireDpcList (
// PKPRCB Prcb,
// )
// Routine Description:
// This routine is called to retire the specified deferred procedure
// call list. DPC routines are called using the idle thread (current)
// stack.
// N.B. Interrupts must be disabled on entry to this routine. Control is returned
// to the caller with the same conditions true.
// Arguments:
// a0 - Address of the current PRCB.
// Return value:
// None.
NESTED_ENTRY(KiRetireDpcList)
NESTED_SETUP(1,2,4,0)
PROLOGUE_END
Krdl_Restart:
add t0 = PbDpcQueueDepth, a0
add t1 = PbDpcRoutineActive, a0
add t2 = PbDpcLock, a0
;;
ld4 t4 = [t0]
add t3 = PbDpcListHead+LsFlink, a0
;;
Krdl_Restart2:
cmp4.eq pt1 = zero, t4
st4 [t1] = t4
(pt1) br.spnt Krdl_Exit
;;
#if !defined(NT_UP)
ACQUIRE_SPINLOCK(t2, a0, Krdl_20)
#endif // !defined(NT_UP)
ld4 t4 = [t0]
LDPTR (t5, t3) // -> first DPC entry
;;
cmp4.eq pt1, pt2 = zero, t4
;;
(pt2) add t10 = LsFlink, t5
(pt2) add out0 = -DpDpcListEntry, t5
(pt1) br.spnt Krdl_Unlock
;;
LDPTR (t6, t10)
add t11 = DpDeferredRoutine, out0
add t12 = DpSystemArgument1, out0
;;
// Setup call to DPC routine
// arguments are:
// dpc object address (out0)
// deferred context (out1)
// system argument 1 (out2)
// system argument 2 (out3)
// N.B. the arguments must be loaded from the DPC object BEFORE
// the inserted flag is cleared to prevent the object being
// overwritten before its time.
ld8.nt1 t13 = [t11], DpDeferredContext-DpDeferredRoutine
ld8.nt1 out2 = [t12], DpSystemArgument2-DpSystemArgument1
;;
ld8.nt1 out1 = [t11], DpLock-DpDeferredContext
ld8.nt1 out3 = [t12]
add t4 = -1, t4
STPTRINC (t3, t6, -LsFlink)
ld8.nt1 t14 = [t13], 8
add t15 = LsBlink, t6
;;
ld8.nt1 gp = [t13]
STPTR (t15, t3)
STPTR (t11, zero)
st4 [t0] = t4
#if !defined(NT_UP)
RELEASE_SPINLOCK(t2) // set spin lock not owned
#endif //!defined(NT_UP)
FAST_ENABLE_INTERRUPTS
mov bt0 = t14
br.call.sptk.few.clr brp = bt0 // call DPC routine
;;
// Check to determine if any more DPCs are available to process.
FAST_DISABLE_INTERRUPTS
br Krdl_Restart
;;
// The DPC list became empty while we were acquiring the DPC queue lock.
// Clear DPC routine active. The race condition mentioned above doesn't
// exist here because we hold the DPC queue lock.
Krdl_Unlock:
#if !defined(NT_UP)
add t2 = PbDpcLock, a0
;;
RELEASE_SPINLOCK(t2)
#endif // !defined(NT_UP)
Krdl_Exit:
add t0 = PbDpcQueueDepth, a0
add t1 = PbDpcRoutineActive, a0
add out0 = PbDpcInterruptRequested, a0
;;
st4.nta [t1] = zero
st4.rel.nta [out0] = zero
add t2 = PbDpcLock, a0
ld4 t4 = [t0]
add t3 = PbDpcListHead+LsFlink, a0
;;
cmp4.eq pt1, pt2 = zero, t4
(pt2) br.spnt Krdl_Restart2
;;
NESTED_RETURN
NESTED_EXIT(KiRetireDpcList)
SBTTL("Dispatch Interrupt")
// Routine:
// KiDispatchInterrupt
// Routine Description:
// This routine is entered as the result of a software interrupt generated
// at DISPATCH_LEVEL. Its function is to process the Deferred Procedure Call
// (DPC) list, and then perform a context switch if a new thread has been
// selected for execution on the processor.
// This routine is entered at IRQL DISPATCH_LEVEL with the dispatcher
// database unlocked. When a return to the caller finally occurs, the
// IRQL remains at DISPATCH_LEVEL, and the dispatcher database is still
// unlocked.
// N.B. On entry to this routine the volatile states (excluding high
// floating point register set) have been saved.
// On entry:
// sp - points to stack scratch area.
// Arguments:
// None
// Return Value:
// None.
NESTED_ENTRY(KiDispatchInterrupt)
PROLOGUE_BEGIN
.regstk 0, 4, 1,0
alloc t16 = ar.pfs, 0, 4, 1, 0
.save rp, loc0
mov loc0 = brp
.fframe SwitchFrameLength
add sp = -SwitchFrameLength, sp
;;
.save ar.unat, loc1
mov loc1 = ar.unat
add t0 = ExFltS19+SwExFrame+STACK_SCRATCH_AREA, sp
add t1 = ExFltS18+SwExFrame+STACK_SCRATCH_AREA, sp
;;
.save.gf 0x0, 0xC0000
stf.spill [t0] = fs19, ExFltS17-ExFltS19
stf.spill [t1] = fs18, ExFltS16-ExFltS18
;;
.save.gf 0x0, 0x30000
stf.spill [t0] = fs17, ExFltS15-ExFltS17
stf.spill [t1] = fs16, ExFltS14-ExFltS16
mov t10 = bs4
;;
.save.gf 0x0, 0xC000
stf.spill [t0] = fs15, ExFltS13-ExFltS15
stf.spill [t1] = fs14, ExFltS12-ExFltS14
mov t11 = bs3
;;
.save.gf 0x0, 0x3000
stf.spill [t0] = fs13, ExFltS11-ExFltS13
stf.spill [t1] = fs12, ExFltS10-ExFltS12
mov t12 = bs2
;;
.save.gf 0x0, 0xC00
stf.spill [t0] = fs11, ExFltS9-ExFltS11
stf.spill [t1] = fs10, ExFltS8-ExFltS10
mov t13 = bs1
;;
.save.gf 0x0, 0x300
stf.spill [t0] = fs9, ExFltS7-ExFltS9
stf.spill [t1] = fs8, ExFltS6-ExFltS8
mov t14 = bs0
;;
.save.gf 0x0, 0xC0
stf.spill [t0] = fs7, ExFltS5-ExFltS7
stf.spill [t1] = fs6, ExFltS4-ExFltS6
mov t15 = ar.lc
;;
.save.gf 0x0, 0x30
stf.spill [t0] = fs5, ExFltS3-ExFltS5
stf.spill [t1] = fs4, ExFltS2-ExFltS4
;;
.save.f 0xC
stf.spill [t0] = fs3, ExFltS1-ExFltS3 // save fs3
stf.spill [t1] = fs2, ExFltS0-ExFltS2 // save fs2
;;
.save.f 0x3
stf.spill [t0] = fs1, ExBrS4-ExFltS1 // save fs1
stf.spill [t1] = fs0, ExBrS3-ExFltS0 // save fs0
;;
.save.b 0x18
st8 [t0] = t10, ExBrS2-ExBrS4 // save bs4
st8 [t1] = t11, ExBrS1-ExBrS3 // save bs3
;;
.save.b 0x6
st8 [t0] = t12, ExBrS0-ExBrS2 // save bs2
st8 [t1] = t13, ExIntS2-ExBrS1 // save bs1
;;
.save.b 0x1
st8 [t0] = t14, ExIntS3-ExBrS0 // save bs0
;;
.save.gf 0xC, 0x0
.mem.offset 0,0
st8.spill [t0] = s3, ExIntS1-ExIntS3 // save s3
.mem.offset 8,0
st8.spill [t1] = s2, ExIntS0-ExIntS2 // save s2
;;
.save.gf 0x3, 0x0
.mem.offset 0,0
st8.spill [t0] = s1, ExApLC-ExIntS1 // save s1
.mem.offset 8,0
st8.spill [t1] = s0, ExApEC-ExIntS0 // save s0
;;
.savepsp ar.pfs, ExceptionFrameLength-ExApEC-STACK_SCRATCH_AREA
st8 [t1] = t16, ExIntNats-ExApEC
mov t4 = ar.unat // captured Nats of s0-s3
;;
.savepsp ar.lc, ExceptionFrameLength-ExApLC-STACK_SCRATCH_AREA
st8 [t0] = t15
.savepsp @priunat, ExceptionFrameLength-ExIntNats-STACK_SCRATCH_AREA
st8 [t1] = t4 // save Nats of s0-s3
PROLOGUE_END
// Register aliases
rPrcb = loc2
rKerGP = loc3
rpT1 = t0
rpT2 = t1
rT1 = t2
rT2 = t3
rpDPLock = t4 // pointer to dispatcher lock
pNoTh = pt1 // No next thread to run
pNext = pt2 // next thread not null
pNull = pt3 // no thread available
pOwned = pt4 // dispatcher lock already owned
pNotOwned = pt5
pQEnd = pt6 // quantum end request pending
pNoQEnd = pt7 // no quantum end request pending
// Increment the dispatch interrupt count
mov rKerGP = gp // save gp
movl rPrcb = KiPcr + PcPrcb
;;
LDPTR (rPrcb, rPrcb) // rPrcb -> Prcb
;;
add rpT1 = PbDispatchInterruptCount, rPrcb
;;
ld4 rT1 = [rpT1]
;;
add rT1 = rT1, zero, 1
;;
st4 [rpT1] = rT1
// **** TBD **** use alpha optimization to first check Dpc Q depth
// Process the DPC list
Kdi_PollDpcList:
// Process the deferred procedure call list.
FAST_ENABLE_INTERRUPTS
;;
srlz.d
;;
// **** TBD ***** No stack switch as in alpha, mips...
// Save current initial stack address and set new initial stack address.
FAST_DISABLE_INTERRUPTS
mov out0 = rPrcb
br.call.sptk brp = KiRetireDpcList
;;
// Check to determine if quantum end has occured.
// N.B. If a new thread is selected as a result of processing a quantum
// end request, then the new thread is returned with the dispatcher
// database locked. Otherwise, NULL is returned with the dispatcher
// database unlocked.
FAST_ENABLE_INTERRUPTS
add rpT1 = PbQuantumEnd, rPrcb
;;
ld4 rT1 = [rpT1] // get quantum end indicator
;;
cmp4.ne pQEnd, pNoQEnd = rT1, zero // if zero, no quantum end reqs
mov gp = rKerGP // restore gp
;;
(pQEnd) st4 [rpT1] = zero // clear quantum end indicator
(pNoQEnd) br.cond.sptk Kdi_NoQuantumEnd
(pQEnd) br.call.spnt brp = KiQuantumEnd // call KiQuantumEnd (C code)
;;
cmp4.eq pNoTh, pNext = v0, zero // pNoTh = no next thread
(pNoTh) br.dpnt Kdi_Exit // br to exit if no next thread
(pNext) br.dpnt Kdi_Swap // br to swap to next thread
// If no quantum end requests:
// Check to determine if a new thread has been selected for execution on
// this processor.
Kdi_NoQuantumEnd:
add rpT2 = PbNextThread, rPrcb
;;
LDPTR (rT1, rpT2) // rT1 = address of next thread object
;;
cmp.eq pNull = rT1, zero // pNull => no thread selected
(pNull) br.dpnt Kdi_Exit // exit if no thread selected
#if !defined(NT_UP)
// Disable interrupts and try to acquire the dispatcher database lock.
FAST_DISABLE_INTERRUPTS
add rpDPLock = @gprel(KiDispatcherLock), gp
;;
xchg8.nt1 rT2 = [rpDPLock], rpDPLock // try to obtain lock
;;
cmp.ne pOwned, pNotOwned = zero, rT2 // pOwned = 1 if not free
;;
PSET_IRQL(pNotOwned, SYNCH_LEVEL)
(pOwned) br.dpnt Kdi_PollDpcList // br out if owned
;;
// Lock obtained -- raise IRQL to synchronization level
FAST_ENABLE_INTERRUPTS
#endif // !defined(NT_UP)
// Reread address of next thread object since it is possible for it to
// change in a multiprocessor system.
Kdi_Swap:
add rpT2 = PbNextThread, rPrcb // -> next thread
movl rpT1 = KiPcr + PcCurrentThread
;;
LDPTR (s1, rpT1) // current thread object
LDPTR (s2, rpT2) // next thread object
add rpT1 = PbCurrentThread, rPrcb
;;
// Reready current thread for execution and swap context to the selected thread.
STPTR (rpT2, zero) // clear addr of next thread
STPTR (rpT1, s2) // set addr of current thread
mov out0 = s1 // set addr of previous thread
mov gp =rKerGP // restore gp
br.call.sptk brp = KiReadyThread // call KiReadyThread(OldTh)
;;
mov gp = rKerGP // restore gp
mov s0 = rPrcb // setup call
br.call.sptk brp = SwapContext // call SwapContext(Prcb, OldTh, NewTh)
;;
// Restore saved registers, and return.
add out0 = STACK_SCRATCH_AREA+SwExFrame, sp
br.call.sptk brp = KiRestoreExceptionFrame
;;
Kdi_Exit:
add rpT1 = ExApEC+SwExFrame+STACK_SCRATCH_AREA, sp
;;
ld8 rT1 = [rpT1]
mov brp = loc0
;;
mov ar.unat = loc1
mov ar.pfs = rT1
.restore
add sp = SwitchFrameLength, sp
br.ret.sptk brp
NESTED_EXIT(KiDispatchInterrupt)