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| author | David Hildenbrand <dahi@linux.vnet.ibm.com> | 2016-05-27 23:03:52 +0300 |
|---|---|---|
| committer | Christian Borntraeger <borntraeger@de.ibm.com> | 2016-06-21 10:43:44 +0300 |
| commit | adbf16985c387851fd3454ca34893705dbde7f98 (patch) | |
| tree | da60441f03e9b218ea1a8f822b46558c2da92756 /arch/s390/kvm | |
| parent | 1b7029bec18718eca8cfc5c1c0917444f019be1e (diff) | |
| download | linux-adbf16985c387851fd3454ca34893705dbde7f98.tar.xz | |
KVM: s390: vsie: speed up VCPU irq delivery when handling vsie
Whenever we want to wake up a VCPU (e.g. when injecting an IRQ), we
have to kick it out of vsie, so the request will be handled faster.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Diffstat (limited to 'arch/s390/kvm')
| -rw-r--r-- | arch/s390/kvm/interrupt.c | 5 | ||||
| -rw-r--r-- | arch/s390/kvm/kvm-s390.h | 1 | ||||
| -rw-r--r-- | arch/s390/kvm/vsie.c | 35 |
3 files changed, 41 insertions, 0 deletions
diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c index d72c4a877622..ca19627779db 100644 --- a/arch/s390/kvm/interrupt.c +++ b/arch/s390/kvm/interrupt.c @@ -995,6 +995,11 @@ void kvm_s390_vcpu_wakeup(struct kvm_vcpu *vcpu) swake_up(&vcpu->wq); vcpu->stat.halt_wakeup++; } + /* + * The VCPU might not be sleeping but is executing the VSIE. Let's + * kick it, so it leaves the SIE to process the request. + */ + kvm_s390_vsie_kick(vcpu); } enum hrtimer_restart kvm_s390_idle_wakeup(struct hrtimer *timer) diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h index b137fbaac91c..ffbbdd285385 100644 --- a/arch/s390/kvm/kvm-s390.h +++ b/arch/s390/kvm/kvm-s390.h @@ -254,6 +254,7 @@ int kvm_s390_handle_eb(struct kvm_vcpu *vcpu); /* implemented in vsie.c */ int kvm_s390_handle_vsie(struct kvm_vcpu *vcpu); +void kvm_s390_vsie_kick(struct kvm_vcpu *vcpu); void kvm_s390_vsie_gmap_notifier(struct gmap *gmap, unsigned long start, unsigned long end); void kvm_s390_vsie_init(struct kvm *kvm); diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c index 7482488d21d0..c8c8763e7822 100644 --- a/arch/s390/kvm/vsie.c +++ b/arch/s390/kvm/vsie.c @@ -838,6 +838,23 @@ static int acquire_gmap_shadow(struct kvm_vcpu *vcpu, } /* + * Register the shadow scb at the VCPU, e.g. for kicking out of vsie. + */ +static void register_shadow_scb(struct kvm_vcpu *vcpu, + struct vsie_page *vsie_page) +{ + WRITE_ONCE(vcpu->arch.vsie_block, &vsie_page->scb_s); +} + +/* + * Unregister a shadow scb from a VCPU. + */ +static void unregister_shadow_scb(struct kvm_vcpu *vcpu) +{ + WRITE_ONCE(vcpu->arch.vsie_block, NULL); +} + +/* * Run the vsie on a shadowed scb, managing the gmap shadow, handling * prefix pages and faults. * @@ -860,6 +877,7 @@ static int vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) rc = do_vsie_run(vcpu, vsie_page); gmap_enable(vcpu->arch.gmap); } + atomic_andnot(PROG_BLOCK_SIE, &scb_s->prog20); if (rc == -EAGAIN) rc = 0; @@ -1000,7 +1018,9 @@ int kvm_s390_handle_vsie(struct kvm_vcpu *vcpu) rc = pin_blocks(vcpu, vsie_page); if (rc) goto out_unshadow; + register_shadow_scb(vcpu, vsie_page); rc = vsie_run(vcpu, vsie_page); + unregister_shadow_scb(vcpu); unpin_blocks(vcpu, vsie_page); out_unshadow: unshadow_scb(vcpu, vsie_page); @@ -1039,3 +1059,18 @@ void kvm_s390_vsie_destroy(struct kvm *kvm) kvm->arch.vsie.page_count = 0; mutex_unlock(&kvm->arch.vsie.mutex); } + +void kvm_s390_vsie_kick(struct kvm_vcpu *vcpu) +{ + struct kvm_s390_sie_block *scb = READ_ONCE(vcpu->arch.vsie_block); + + /* + * Even if the VCPU lets go of the shadow sie block reference, it is + * still valid in the cache. So we can safely kick it. + */ + if (scb) { + atomic_or(PROG_BLOCK_SIE, &scb->prog20); + if (scb->prog0c & PROG_IN_SIE) + atomic_or(CPUSTAT_STOP_INT, &scb->cpuflags); + } +} |