list_del(&vcpu->arch.run_list);
}
+static int kvmppc_grab_hwthread(int cpu)
+{
+ struct paca_struct *tpaca;
+ long timeout = 1000;
+
+ tpaca = &paca[cpu];
+
+ /* Ensure the thread won't go into the kernel if it wakes */
+ tpaca->kvm_hstate.hwthread_req = 1;
+
+ /*
+ * If the thread is already executing in the kernel (e.g. handling
+ * a stray interrupt), wait for it to get back to nap mode.
+ * The smp_mb() is to ensure that our setting of hwthread_req
+ * is visible before we look at hwthread_state, so if this
+ * races with the code at system_reset_pSeries and the thread
+ * misses our setting of hwthread_req, we are sure to see its
+ * setting of hwthread_state, and vice versa.
+ */
+ smp_mb();
+ while (tpaca->kvm_hstate.hwthread_state == KVM_HWTHREAD_IN_KERNEL) {
+ if (--timeout <= 0) {
+ pr_err("KVM: couldn't grab cpu %d\n", cpu);
+ return -EBUSY;
+ }
+ udelay(1);
+ }
+ return 0;
+}
+
+static void kvmppc_release_hwthread(int cpu)
+{
+ struct paca_struct *tpaca;
+
+ tpaca = &paca[cpu];
+ tpaca->kvm_hstate.hwthread_req = 0;
+ tpaca->kvm_hstate.kvm_vcpu = NULL;
+}
+
static void kvmppc_start_thread(struct kvm_vcpu *vcpu)
{
int cpu;
smp_wmb();
#if defined(CONFIG_PPC_ICP_NATIVE) && defined(CONFIG_SMP)
if (vcpu->arch.ptid) {
- tpaca->cpu_start = 0x80;
- wmb();
+ kvmppc_grab_hwthread(cpu);
xics_wake_cpu(cpu);
++vc->n_woken;
}
struct kvm_vcpu *vcpu, *vcpu0, *vnext;
long ret;
u64 now;
- int ptid;
+ int ptid, i;
/* don't start if any threads have a signal pending */
list_for_each_entry(vcpu, &vc->runnable_threads, arch.run_list)
vc->napping_threads = 0;
list_for_each_entry(vcpu, &vc->runnable_threads, arch.run_list)
kvmppc_start_thread(vcpu);
+ /* Grab any remaining hw threads so they can't go into the kernel */
+ for (i = ptid; i < threads_per_core; ++i)
+ kvmppc_grab_hwthread(vc->pcpu + i);
preempt_disable();
spin_unlock(&vc->lock);
kvm_guest_enter();
__kvmppc_vcore_entry(NULL, vcpu0);
+ for (i = 0; i < threads_per_core; ++i)
+ kvmppc_release_hwthread(vc->pcpu + i);
spin_lock(&vc->lock);
/* disable sending of IPIs on virtual external irqs */
#include <asm/hvcall.h>
#include <asm/asm-offsets.h>
#include <asm/exception-64s.h>
+#include <asm/kvm_book3s_asm.h>
/*****************************************************************************
* *
#define XICS_XIRR 4
#define XICS_QIRR 0xc
+#define XICS_IPI 2 /* interrupt source # for IPIs */
/*
* We come in here when wakened from nap mode on a secondary hw thread.
subi r1,r1,STACK_FRAME_OVERHEAD
ld r2,PACATOC(r13)
- /* were we napping due to cede? */
- lbz r0,HSTATE_NAPPING(r13)
- cmpwi r0,0
- bne kvm_end_cede
+ li r0,KVM_HWTHREAD_IN_KVM
+ stb r0,HSTATE_HWTHREAD_STATE(r13)
- /* get vcpu pointer */
- ld r4, HSTATE_KVM_VCPU(r13)
+ /* NV GPR values from power7_idle() will no longer be valid */
+ li r0,1
+ stb r0,PACA_NAPSTATELOST(r13)
- /* We got here with an IPI; clear it */
- ld r5, HSTATE_XICS_PHYS(r13)
- li r0, 0xff
- li r6, XICS_QIRR
- li r7, XICS_XIRR
- lwzcix r8, r5, r7 /* ack the interrupt */
+ /* get vcpu pointer, NULL if we have no vcpu to run */
+ ld r4,HSTATE_KVM_VCPU(r13)
+ cmpdi cr1,r4,0
+
+ /* 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 27f
+
+ /*
+ * External interrupt - for now assume it is an IPI, since we
+ * should never get any other interrupts sent to offline threads.
+ * Only do this for secondary threads.
+ */
+ beq cr1,25f
+ lwz r3,VCPU_PTID(r4)
+ cmpwi r3,0
+ beq 27f
+25: ld r5,HSTATE_XICS_PHYS(r13)
+ li r0,0xff
+ li r6,XICS_QIRR
+ li r7,XICS_XIRR
+ lwzcix r8,r5,r7 /* get and ack the interrupt */
sync
- stbcix r0, r5, r6 /* clear it */
- stwcix r8, r5, r7 /* EOI it */
+ clrldi. r9,r8,40 /* get interrupt source ID. */
+ beq 27f /* none there? */
+ cmpwi r9,XICS_IPI
+ bne 26f
+ stbcix r0,r5,r6 /* clear IPI */
+26: stwcix r8,r5,r7 /* EOI the interrupt */
- /* NV GPR values from power7_idle() will no longer be valid */
- stb r0, PACA_NAPSTATELOST(r13)
+27: /* XXX should handle hypervisor maintenance interrupts etc. here */
+
+ /* if we have no vcpu to run, go back to sleep */
+ beq cr1,kvm_no_guest
+
+ /* were we napping due to cede? */
+ lbz r0,HSTATE_NAPPING(r13)
+ cmpwi r0,0
+ bne kvm_end_cede
.global kvmppc_hv_entry
kvmppc_hv_entry:
* Take a nap until a decrementer or external interrupt occurs,
* with PECE1 (wake on decr) and PECE0 (wake on external) set in LPCR
*/
- li r0,0x80
- stb r0,PACAPROCSTART(r13)
+ li r0,1
+ stb r0,HSTATE_HWTHREAD_REQ(r13)
mfspr r5,SPRN_LPCR
ori r5,r5,LPCR_PECE0 | LPCR_PECE1
mtspr SPRN_LPCR,r5
kvm_end_cede:
/* Woken by external or decrementer interrupt */
ld r1, HSTATE_HOST_R1(r13)
- ld r2, PACATOC(r13)
- /* If we're a secondary thread and we got here by an IPI, ack it */
- ld r4,HSTATE_KVM_VCPU(r13)
- lwz r3,VCPU_PTID(r4)
- cmpwi r3,0
- beq 27f
- mfspr r3,SPRN_SRR1
- rlwinm r3,r3,44-31,0x7 /* extract wake reason field */
- cmpwi r3,4 /* was it an external interrupt? */
- bne 27f
- ld r5, HSTATE_XICS_PHYS(r13)
- li r0,0xff
- li r6,XICS_QIRR
- li r7,XICS_XIRR
- lwzcix r8,r5,r7 /* ack the interrupt */
- sync
- stbcix r0,r5,r6 /* clear it */
- stwcix r8,r5,r7 /* EOI it */
-27:
/* load up FP state */
bl kvmppc_load_fp
stwcx. r3, 0, r4
bne 51b
+kvm_no_guest:
+ li r0, KVM_HWTHREAD_IN_NAP
+ stb r0, HSTATE_HWTHREAD_STATE(r13)
+ li r0, 0
+ std r0, HSTATE_KVM_VCPU(r13)
+
li r3, LPCR_PECE0
mfspr r4, SPRN_LPCR
rlwimi r4, r3, 0, LPCR_PECE0 | LPCR_PECE1
mtspr SPRN_LPCR, r4
isync
- li r0, 0
std r0, HSTATE_SCRATCH0(r13)
ptesync
ld r0, HSTATE_SCRATCH0(r13)