@@ -87,6 +87,7 @@ struct kvmppc_host_state {
u8 hwthread_req;
u8 hwthread_state;
u8 host_ipi;
+ u8 ptid;
struct kvm_vcpu *kvm_vcpu;
struct kvmppc_vcore *kvm_vcore;
unsigned long xics_phys;
@@ -284,6 +284,8 @@ struct kvmppc_vcore {
int n_woken;
int nap_count;
int napping_threads;
+ int real_mode_threads;
+ int first_vcpuid;
u16 pcpu;
u16 last_cpu;
u8 vcore_state;
@@ -294,6 +296,7 @@ struct kvmppc_vcore {
u64 stolen_tb;
u64 preempt_tb;
struct kvm_vcpu *runner;
+ struct kvm *kvm;
u64 tb_offset; /* guest timebase - host timebase */
u32 arch_compat;
ulong pcr;
@@ -575,6 +578,7 @@ struct kvm_vcpu_arch {
int state;
int ptid;
bool timer_running;
+ u8 is_master;
wait_queue_head_t cpu_run;
struct kvm_vcpu_arch_shared *shared;
@@ -514,13 +514,15 @@ int main(void)
DEFINE(VCPU_FAULT_DAR, offsetof(struct kvm_vcpu, arch.fault_dar));
DEFINE(VCPU_LAST_INST, offsetof(struct kvm_vcpu, arch.last_inst));
DEFINE(VCPU_TRAP, offsetof(struct kvm_vcpu, arch.trap));
- DEFINE(VCPU_PTID, offsetof(struct kvm_vcpu, arch.ptid));
+ DEFINE(VCPU_IS_MASTER, offsetof(struct kvm_vcpu, arch.is_master));
DEFINE(VCPU_CFAR, offsetof(struct kvm_vcpu, arch.cfar));
DEFINE(VCPU_PPR, offsetof(struct kvm_vcpu, arch.ppr));
DEFINE(VCORE_ENTRY_EXIT, offsetof(struct kvmppc_vcore, entry_exit_count));
DEFINE(VCORE_NAP_COUNT, offsetof(struct kvmppc_vcore, nap_count));
DEFINE(VCORE_IN_GUEST, offsetof(struct kvmppc_vcore, in_guest));
DEFINE(VCORE_NAPPING_THREADS, offsetof(struct kvmppc_vcore, napping_threads));
+ DEFINE(VCORE_RM_THREADS, offsetof(struct kvmppc_vcore, real_mode_threads));
+ DEFINE(VCORE_KVM, offsetof(struct kvmppc_vcore, kvm));
DEFINE(VCORE_TB_OFFSET, offsetof(struct kvmppc_vcore, tb_offset));
DEFINE(VCORE_PCR, offsetof(struct kvmppc_vcore, pcr));
DEFINE(VCPU_SVCPU, offsetof(struct kvmppc_vcpu_book3s, shadow_vcpu) -
@@ -590,6 +592,7 @@ int main(void)
HSTATE_FIELD(HSTATE_XICS_PHYS, xics_phys);
HSTATE_FIELD(HSTATE_SAVED_XIRR, saved_xirr);
HSTATE_FIELD(HSTATE_HOST_IPI, host_ipi);
+ HSTATE_FIELD(HSTATE_PTID, ptid);
HSTATE_FIELD(HSTATE_MMCR, host_mmcr);
HSTATE_FIELD(HSTATE_PMC, host_pmc);
HSTATE_FIELD(HSTATE_PURR, host_purr);
@@ -1030,6 +1030,8 @@ struct kvm_vcpu *kvmppc_core_vcpu_create(struct kvm *kvm, unsigned int id)
spin_lock_init(&vcore->lock);
init_waitqueue_head(&vcore->wq);
vcore->preempt_tb = TB_NIL;
+ vcore->first_vcpuid = core * threads_per_core;
+ vcore->kvm = kvm;
}
kvm->arch.vcores[core] = vcore;
kvm->arch.online_vcores++;
@@ -1043,6 +1045,7 @@ struct kvm_vcpu *kvmppc_core_vcpu_create(struct kvm *kvm, unsigned int id)
++vcore->num_threads;
spin_unlock(&vcore->lock);
vcpu->arch.vcore = vcore;
+ vcpu->arch.ptid = vcpu->vcpu_id - vcore->first_vcpuid;
vcpu->arch.cpu_type = KVM_CPU_3S_64;
kvmppc_sanity_check(vcpu);
@@ -1100,7 +1103,7 @@ static void kvmppc_end_cede(struct kvm_vcpu *vcpu)
}
}
-extern int __kvmppc_vcore_entry(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu);
+extern void __kvmppc_vcore_entry(void);
static void kvmppc_remove_runnable(struct kvmppc_vcore *vc,
struct kvm_vcpu *vcpu)
@@ -1174,13 +1177,14 @@ static void kvmppc_start_thread(struct kvm_vcpu *vcpu)
tpaca = &paca[cpu];
tpaca->kvm_hstate.kvm_vcpu = vcpu;
tpaca->kvm_hstate.kvm_vcore = vc;
- tpaca->kvm_hstate.napping = 0;
+ tpaca->kvm_hstate.ptid = vcpu->arch.ptid;
vcpu->cpu = vc->pcpu;
smp_wmb();
#if defined(CONFIG_PPC_ICP_NATIVE) && defined(CONFIG_SMP)
- if (vcpu->arch.ptid) {
+ if (cpu != smp_processor_id()) {
xics_wake_cpu(cpu);
- ++vc->n_woken;
+ if (vcpu->arch.ptid)
+ ++vc->n_woken;
}
#endif
}
@@ -1237,10 +1241,10 @@ static int on_primary_thread(void)
*/
static void kvmppc_run_core(struct kvmppc_vcore *vc)
{
- struct kvm_vcpu *vcpu, *vcpu0, *vnext;
+ struct kvm_vcpu *vcpu, *vnext;
long ret;
u64 now;
- int ptid, i, need_vpa_update;
+ int i, need_vpa_update;
int srcu_idx;
struct kvm_vcpu *vcpus_to_update[threads_per_core];
@@ -1265,6 +1269,7 @@ static void kvmppc_run_core(struct kvmppc_vcore *vc)
vc->vcore_state = VCORE_STARTING;
vc->in_guest = 0;
vc->napping_threads = 0;
+ vc->real_mode_threads = 0;
/*
* Updating any of the vpas requires calling kvmppc_pin_guest_page,
@@ -1278,25 +1283,6 @@ static void kvmppc_run_core(struct kvmppc_vcore *vc)
}
/*
- * Assign physical thread IDs, first to non-ceded vcpus
- * and then to ceded ones.
- */
- ptid = 0;
- vcpu0 = NULL;
- list_for_each_entry(vcpu, &vc->runnable_threads, arch.run_list) {
- if (!vcpu->arch.ceded) {
- if (!ptid)
- vcpu0 = vcpu;
- vcpu->arch.ptid = ptid++;
- }
- }
- if (!vcpu0)
- goto out; /* nothing to run; should never happen */
- list_for_each_entry(vcpu, &vc->runnable_threads, arch.run_list)
- if (vcpu->arch.ceded)
- vcpu->arch.ptid = ptid++;
-
- /*
* Make sure we are running on thread 0, and that
* secondary threads are offline.
*/
@@ -1312,15 +1298,19 @@ static void kvmppc_run_core(struct kvmppc_vcore *vc)
kvmppc_create_dtl_entry(vcpu, vc);
}
+ /* Set this explicitly in case thread 0 doesn't have a vcpu */
+ get_paca()->kvm_hstate.kvm_vcore = vc;
+ get_paca()->kvm_hstate.ptid = 0;
+
vc->vcore_state = VCORE_RUNNING;
preempt_disable();
spin_unlock(&vc->lock);
kvm_guest_enter();
- srcu_idx = srcu_read_lock(&vcpu0->kvm->srcu);
+ srcu_idx = srcu_read_lock(&vc->kvm->srcu);
- __kvmppc_vcore_entry(NULL, vcpu0);
+ __kvmppc_vcore_entry();
spin_lock(&vc->lock);
/* disable sending of IPIs on virtual external irqs */
@@ -1335,7 +1325,7 @@ static void kvmppc_run_core(struct kvmppc_vcore *vc)
vc->vcore_state = VCORE_EXITING;
spin_unlock(&vc->lock);
- srcu_read_unlock(&vcpu0->kvm->srcu, srcu_idx);
+ srcu_read_unlock(&vc->kvm->srcu, srcu_idx);
/* make sure updates to secondary vcpu structs are visible now */
smp_mb();
@@ -1443,7 +1433,6 @@ static int kvmppc_run_vcpu(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu)
if (!signal_pending(current)) {
if (vc->vcore_state == VCORE_RUNNING &&
VCORE_EXIT_COUNT(vc) == 0) {
- vcpu->arch.ptid = vc->n_runnable - 1;
kvmppc_create_dtl_entry(vcpu, vc);
kvmppc_start_thread(vcpu);
} else if (vc->vcore_state == VCORE_SLEEPING) {
@@ -1474,6 +1463,7 @@ static int kvmppc_run_vcpu(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu)
if (!vc->n_runnable || vcpu->arch.state != KVMPPC_VCPU_RUNNABLE)
break;
vc->runner = vcpu;
+ vcpu->arch.is_master = 1;
n_ceded = 0;
list_for_each_entry(v, &vc->runnable_threads, arch.run_list) {
if (!v->arch.pending_exceptions)
@@ -1486,6 +1476,7 @@ static int kvmppc_run_vcpu(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu)
else
kvmppc_run_core(vc);
vc->runner = NULL;
+ vcpu->arch.is_master = 0;
}
while (vcpu->arch.state == KVMPPC_VCPU_RUNNABLE &&
@@ -35,7 +35,7 @@
****************************************************************************/
/* Registers:
- * r4: vcpu pointer
+ * none
*/
_GLOBAL(__kvmppc_vcore_entry)
@@ -69,7 +69,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_206)
mtmsrd r10,1
/* Save host PMU registers */
- /* R4 is live here (vcpu pointer) but not r3 or r5 */
li r3, 1
sldi r3, r3, 31 /* MMCR0_FC (freeze counters) bit */
mfspr r7, SPRN_MMCR0 /* save MMCR0 */
@@ -134,16 +133,15 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_201)
* enters the guest with interrupts enabled.
*/
BEGIN_FTR_SECTION
+ ld r4, HSTATE_KVM_VCPU(r13)
ld r0, VCPU_PENDING_EXC(r4)
li r7, (1 << BOOK3S_IRQPRIO_EXTERNAL)
oris r7, r7, (1 << BOOK3S_IRQPRIO_EXTERNAL_LEVEL)@h
and. r0, r0, r7
beq 32f
- mr r31, r4
lhz r3, PACAPACAINDEX(r13)
bl smp_send_reschedule
nop
- mr r4, r31
32:
END_FTR_SECTION_IFSET(CPU_FTR_ARCH_201)
#endif /* CONFIG_SMP */
@@ -53,6 +53,10 @@ kvmppc_skip_Hinterrupt:
hrfid
b .
+/* Values in HSTATE_NAPPING(r13) */
+#define NAPPING_CEDE 1
+#define NAPPING_NOVCPU 2
+
/*
* Call kvmppc_hv_entry in real mode.
* Must be called with interrupts hard-disabled.
@@ -77,6 +81,16 @@ _GLOBAL(kvmppc_hv_entry_trampoline)
RFI
kvmppc_call_hv_entry:
+ /* Indicate that we are now in real mode */
+ ld r5, HSTATE_KVM_VCORE(r13)
+ li r0, 1
+ stw r0, VCORE_RM_THREADS(r5)
+
+ /* any guest vcpu to run? */
+ ld r4, HSTATE_KVM_VCPU(r13)
+ cmpdi r4, 0
+ beq kvmppc_call_no_guest
+kvmppc_got_guest:
bl kvmppc_hv_entry
/* Back from guest - restore host state and return to caller */
@@ -91,15 +105,6 @@ kvmppc_call_hv_entry:
ld r3,PACA_SPRG3(r13)
mtspr SPRN_SPRG3,r3
- /*
- * Reload DEC. HDEC interrupts were disabled when
- * we reloaded the host's LPCR value.
- */
- ld r3, HSTATE_DECEXP(r13)
- mftb r4
- subf r4, r4, r3
- mtspr SPRN_DEC, r4
-
/* Reload the host's PMU registers */
ld r3, PACALPPACAPTR(r13) /* is the host using the PMU? */
lbz r4, LPPACA_PMCINUSE(r3)
@@ -134,6 +139,16 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_201)
isync
23:
+kvmppc_vcore_exit:
+ /*
+ * Reload DEC. HDEC interrupts were disabled when
+ * we reloaded the host's LPCR value.
+ */
+ ld r3, HSTATE_DECEXP(r13)
+ mftb r4
+ subf r4, r4, r3
+ mtspr SPRN_DEC, r4
+
/*
* For external and machine check interrupts, we need
* to call the Linux handler to process the interrupt.
@@ -173,16 +188,114 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_206)
13: b machine_check_fwnmi
+kvmppc_call_no_guest:
+ /* We handle this much like a ceded vcpu */
+ /* First wait for the partition switch to happen */
+ HMT_LOW
+3: lbz r3,VCORE_IN_GUEST(r5)
+ cmpwi r3,0
+ beq 3b
+ HMT_MEDIUM
+ /* now load up LPCR */
+ ld r9, VCORE_KVM(r5)
+ ld r8, KVM_LPCR(r9)
+ mtspr SPRN_LPCR, r8
+ isync
+
+ /* set our bit in napping_threads */
+ lbz r7, HSTATE_PTID(r13)
+ li r0, 1
+ sld r0, r0, r7
+ addi r6, r5, VCORE_NAPPING_THREADS
+1: lwarx r3, 0, r6
+ or r3, r3, r0
+ stwcx. r3, 0, r6
+ bne 1b
+ /* order napping_threads update vs testing entry_exit_count */
+ lwsync
+ li r12, 0
+ lwz r7, VCORE_ENTRY_EXIT(r5)
+ cmpwi r7, 0x100
+ bge kvm_novcpu_exit /* another thread already exiting */
+ li r3, NAPPING_NOVCPU
+ stb r3, HSTATE_NAPPING(r13)
+ li r3, 1
+ stb r3, HSTATE_HWTHREAD_REQ(r13)
+ std r1, HSTATE_HOST_R1(r13)
+
+ b kvm_do_nap
+
+kvm_novcpu_wakeup:
+ ld r1, HSTATE_HOST_R1(r13)
+ ld r5, HSTATE_KVM_VCORE(r13)
+ li r0, 0
+ stb r0, HSTATE_NAPPING(r13)
+ stb r0, HSTATE_HWTHREAD_REQ(r13)
+
+ /* see if any other thread is already exiting */
+ li r12, 0
+ lwz r0, VCORE_ENTRY_EXIT(r5)
+ cmpwi r0, 0x100
+ bge kvm_novcpu_exit
+
+ /* clear our bit in napping_threads */
+ lbz r7, HSTATE_PTID(r13)
+ li r0, 1
+ sld r0, r0, r7
+ addi r6, r5, VCORE_NAPPING_THREADS
+4: lwarx r3, 0, r6
+ andc r3, r3, r0
+ stwcx. r3, 0, r6
+ bne 4b
+
+ /* Check the wake reason in SRR1 to see why we got here */
+ mfspr r3, SPRN_SRR1
+ rlwinm r3, r3, 44-31, 0x7 /* extract wake reason field */
+ cmpwi r3, 4 /* was it an external interrupt? */
+ bne kvm_novcpu_exit /* if not, exit the guest */
+
+ /* extern interrupt - read and handle it */
+ li r12, BOOK3S_INTERRUPT_EXTERNAL
+ bl kvmppc_read_intr
+ cmpdi r3, 0
+ bge kvm_novcpu_exit
+ li r12, 0
+
+ /* Got an IPI but other vcpus aren't yet exiting, must be a latecomer */
+ ld r4, HSTATE_KVM_VCPU(r13)
+ cmpdi r4, 0
+ bne kvmppc_got_guest
+
+kvm_novcpu_exit:
+ ld r5, HSTATE_KVM_VCORE(r13)
+
+ /* if other threads aren't yet exiting, poke them to do so */
+ lwz r3, VCORE_ENTRY_EXIT(r5)
+ cmpwi r3, 0x100
+ bge 2f
+ li r3, 0 /* set HDEC to 0 */
+ mtspr SPRN_HDEC, r3
+2:
+ /* wait for the MMU switch */
+ HMT_LOW
+3: lbz r3, VCORE_IN_GUEST(r5)
+ cmpwi r3, 0
+ bne 3b
+ HMT_MEDIUM
+ /* reload host LPCR */
+ ld r9, VCORE_KVM(r5)
+ ld r8, KVM_HOST_LPCR(r9)
+ mtspr SPRN_LPCR, r8
+ isync
+ b kvmppc_vcore_exit
/*
- * We come in here when wakened from nap mode on a secondary hw thread.
+ * We come in here when wakened from nap mode.
* Relocation is off and most register values are lost.
* r13 points to the PACA.
*/
.globl kvm_start_guest
kvm_start_guest:
- ld r1,PACAEMERGSP(r13)
- subi r1,r1,STACK_FRAME_OVERHEAD
ld r2,PACATOC(r13)
li r0,KVM_HWTHREAD_IN_KVM
@@ -194,8 +307,13 @@ kvm_start_guest:
/* were we napping due to cede? */
lbz r0,HSTATE_NAPPING(r13)
- cmpwi r0,0
- bne kvm_end_cede
+ cmpwi r0,NAPPING_CEDE
+ beq kvm_end_cede
+ cmpwi r0,NAPPING_NOVCPU
+ beq kvm_novcpu_wakeup
+
+ ld r1,PACAEMERGSP(r13)
+ subi r1,r1,STACK_FRAME_OVERHEAD
/*
* We weren't napping due to cede, so this must be a secondary
@@ -270,6 +388,7 @@ kvm_start_guest:
kvm_no_guest:
li r0, KVM_HWTHREAD_IN_NAP
stb r0, HSTATE_HWTHREAD_STATE(r13)
+kvm_do_nap:
li r3, LPCR_PECE0
mfspr r4, SPRN_LPCR
rlwimi r4, r3, 0, LPCR_PECE0 | LPCR_PECE1
@@ -443,9 +562,15 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_201)
/* Primary thread switches to guest partition. */
ld r9,VCPU_KVM(r4) /* pointer to struct kvm */
- lwz r6,VCPU_PTID(r4)
+ lbz r6,VCPU_IS_MASTER(r4)
+ cmpwi r6,0
+ beq 20f
+ /* wait for thread 0 to get into real mode */
+ HMT_LOW
+50: lwz r6,VCORE_RM_THREADS(r5)
cmpwi r6,0
- bne 20f
+ beq 50b
+ HMT_MEDIUM
ld r6,KVM_SDR1(r9)
lwz r7,KVM_LPID(r9)
li r0,LPID_RSVD /* switch to reserved LPID */
@@ -1014,8 +1139,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_201)
*/
cmpwi r3,0x100 /* Are we the first here? */
bge 43f
- cmpwi r3,1 /* Are any other threads in the guest? */
- ble 43f
cmpwi r12,BOOK3S_INTERRUPT_HV_DECREMENTER
beq 40f
li r0,0
@@ -1026,7 +1149,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_201)
* doesn't wake CPUs up from nap.
*/
lwz r3,VCORE_NAPPING_THREADS(r5)
- lwz r4,VCPU_PTID(r9)
+ lbz r4,HSTATE_PTID(r13)
li r0,1
sld r0,r0,r4
andc. r3,r3,r0 /* no sense IPI'ing ourselves */
@@ -1046,9 +1169,9 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_201)
/* Secondary threads wait for primary to do partition switch */
43: ld r4,VCPU_KVM(r9) /* pointer to struct kvm */
ld r5,HSTATE_KVM_VCORE(r13)
- lwz r3,VCPU_PTID(r9)
+ lwz r3,VCPU_IS_MASTER(r9)
cmpwi r3,0
- beq 15f
+ bne 15f
HMT_LOW
13: lbz r3,VCORE_IN_GUEST(r5)
cmpwi r3,0
@@ -1315,10 +1438,13 @@ secondary_too_late:
cmpwi r3,0
bne 13b
HMT_MEDIUM
- li r0, KVM_GUEST_MODE_NONE
- stb r0, HSTATE_IN_GUEST(r13)
- ld r11,PACA_SLBSHADOWPTR(r13)
+ ld r6, VCORE_KVM(r5)
+ ld r8, KVM_HOST_LPCR(r6)
+ mtspr SPRN_LPCR, r8
+ isync
+
+ ld r11,PACA_SLBSHADOWPTR(r13)
.rept SLB_NUM_BOLTED
ld r5,SLBSHADOW_SAVEAREA(r11)
ld r6,SLBSHADOW_SAVEAREA+8(r11)
@@ -1327,6 +1453,14 @@ secondary_too_late:
slbmte r6,r5
1: addi r11,r11,16
.endr
+
+ li r6, 0
+ mtspr SPRN_AMR, r6
+ li r0, KVM_GUEST_MODE_NONE
+ stb r0, HSTATE_IN_GUEST(r13)
+ ld r7, HSTATE_DSCR(r13)
+ mtspr SPRN_DSCR, r7
+
b 22b
/*
@@ -1615,7 +1749,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_206)
* up to the host.
*/
ld r5,HSTATE_KVM_VCORE(r13)
- lwz r6,VCPU_PTID(r3)
+ lbz r6,HSTATE_PTID(r13)
lwz r8,VCORE_ENTRY_EXIT(r5)
clrldi r8,r8,56
li r0,1
@@ -1628,7 +1762,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_206)
bge kvm_cede_exit
stwcx. r4,0,r6
bne 31b
- li r0,1
+ li r0,NAPPING_CEDE
stb r0,HSTATE_NAPPING(r13)
/* order napping_threads update vs testing entry_exit_count */
lwsync
@@ -1717,7 +1851,7 @@ kvm_end_cede:
/* clear our bit in vcore->napping_threads */
33: ld r5,HSTATE_KVM_VCORE(r13)
- lwz r3,VCPU_PTID(r4)
+ lbz r3,HSTATE_PTID(r13)
li r0,1
sld r0,r0,r3
addi r6,r5,VCORE_NAPPING_THREADS
On a threaded processor such as POWER7, we group VCPUs into virtual cores and arrange that the VCPUs in a virtual core run on the same physical core. Currently we don't enforce any correspondence between virtual thread numbers within a virtual core and physical thread numbers. Physical threads are allocated starting at 0 on a first-come first-served basis to runnable virtual threads (VCPUs). POWER8 implements a new "msgsndp" instruction which guest kernels can use to interrupt other threads in the same core or sub-core. Since the instruction takes the destination physical thread ID as a parameter, it becomes necessary to align the physical thread IDs with the virtual thread IDs, that is, to make sure virtual thread N within a virtual core always runs on physical thread N. This means that it's possible that thread 0, which is where we call __kvmppc_vcore_entry, may end up running some other vcpu than the one whose task called kvmppc_run_core(), or it may end up running no vcpu at all, if for example thread 0 of the virtual core is currently executing in userspace. Thus we can't rely on thread 0 to be the master responsible for switching the MMU. Instead we now have an explicit 'is_master' flag which is set for the vcpu whose task called kvmppc_run_core(). The master then has to wait for thread 0 to enter real mode before switching the MMU. Also, we no longer pass the vcpu pointer to __kvmppc_vcore_entry, but instead let the assembly code load it from the PACA. Since the assembly code will need to know the kvm pointer and the thread ID for threads which don't have a vcpu, we move the thread ID into the PACA and we add a kvm pointer to the virtual core structure. In the case where thread 0 has no vcpu to run, we arrange for it to go to nap mode, using a new flag value in the PACA 'napping' field so we can differentiate it when it wakes from the other nap cases. We set the bit for the thread in the vcore 'napping_threads' field so that when other threads come out of the guest they will send an IPI to thread 0 to wake it up. When it does wake up, we clear that bit, see what caused the wakeup, and either exit back to the kernel, or start running virtual thread 0 in the case where it now wants to enter the guest and the other threads are still in the guest. Signed-off-by: Paul Mackerras <paulus@samba.org> --- arch/powerpc/include/asm/kvm_book3s_asm.h | 1 + arch/powerpc/include/asm/kvm_host.h | 4 + arch/powerpc/kernel/asm-offsets.c | 5 +- arch/powerpc/kvm/book3s_hv.c | 49 ++++---- arch/powerpc/kvm/book3s_hv_interrupts.S | 6 +- arch/powerpc/kvm/book3s_hv_rmhandlers.S | 188 +++++++++++++++++++++++++----- 6 files changed, 192 insertions(+), 61 deletions(-)