From: Longpeng <longpe...@huawei.com> We invoke the kvm_irqchip_commit_routes() for each addition to MSI route table, which is not efficient if we are adding lots of routes in some cases.
This patch lets callers invoke the kvm_irqchip_commit_routes(), so the callers can decide how to optimize. [1] https://lists.gnu.org/archive/html/qemu-devel/2021-11/msg00967.html Signed-off-by: Longpeng <longpe...@huawei.com> --- accel/kvm/kvm-all.c | 7 ++++--- accel/stubs/kvm-stub.c | 2 +- hw/misc/ivshmem.c | 5 ++++- hw/vfio/pci.c | 5 ++++- hw/virtio/virtio-pci.c | 4 +++- include/sysemu/kvm.h | 4 ++-- target/i386/kvm/kvm.c | 4 +++- 7 files changed, 21 insertions(+), 10 deletions(-) diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c index 0e66ebb497..27864dfaea 100644 --- a/accel/kvm/kvm-all.c +++ b/accel/kvm/kvm-all.c @@ -1961,10 +1961,11 @@ int kvm_irqchip_send_msi(KVMState *s, MSIMessage msg) return kvm_set_irq(s, route->kroute.gsi, 1); } -int kvm_irqchip_add_msi_route(KVMState *s, int vector, PCIDevice *dev) +int kvm_irqchip_add_msi_route(KVMRouteChange *c, int vector, PCIDevice *dev) { struct kvm_irq_routing_entry kroute = {}; int virq; + KVMState *s = c->s; MSIMessage msg = {0, 0}; if (pci_available && dev) { @@ -2004,7 +2005,7 @@ int kvm_irqchip_add_msi_route(KVMState *s, int vector, PCIDevice *dev) kvm_add_routing_entry(s, &kroute); kvm_arch_add_msi_route_post(&kroute, vector, dev); - kvm_irqchip_commit_routes(s); + c->changes++; return virq; } @@ -2162,7 +2163,7 @@ int kvm_irqchip_send_msi(KVMState *s, MSIMessage msg) abort(); } -int kvm_irqchip_add_msi_route(KVMState *s, int vector, PCIDevice *dev) +int kvm_irqchip_add_msi_route(KVMRouteChange *c, int vector, PCIDevice *dev) { return -ENOSYS; } diff --git a/accel/stubs/kvm-stub.c b/accel/stubs/kvm-stub.c index 5319573e00..ae6e8e9aa7 100644 --- a/accel/stubs/kvm-stub.c +++ b/accel/stubs/kvm-stub.c @@ -81,7 +81,7 @@ int kvm_on_sigbus(int code, void *addr) } #ifndef CONFIG_USER_ONLY -int kvm_irqchip_add_msi_route(KVMState *s, int vector, PCIDevice *dev) +int kvm_irqchip_add_msi_route(KVMRouteChange *c, int vector, PCIDevice *dev) { return -ENOSYS; } diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c index 299837e5c1..2307f4a513 100644 --- a/hw/misc/ivshmem.c +++ b/hw/misc/ivshmem.c @@ -424,16 +424,19 @@ static void ivshmem_add_kvm_msi_virq(IVShmemState *s, int vector, Error **errp) { PCIDevice *pdev = PCI_DEVICE(s); + KVMRouteChange c; int ret; IVSHMEM_DPRINTF("ivshmem_add_kvm_msi_virq vector:%d\n", vector); assert(!s->msi_vectors[vector].pdev); - ret = kvm_irqchip_add_msi_route(kvm_state, vector, pdev); + c = kvm_irqchip_begin_route_changes(kvm_state); + ret = kvm_irqchip_add_msi_route(&c, vector, pdev); if (ret < 0) { error_setg(errp, "kvm_irqchip_add_msi_route failed"); return; } + kvm_irqchip_commit_route_changes(&c); s->msi_vectors[vector].virq = ret; s->msi_vectors[vector].pdev = pdev; diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c index 7b45353ce2..d07a4e99b1 100644 --- a/hw/vfio/pci.c +++ b/hw/vfio/pci.c @@ -412,6 +412,7 @@ static int vfio_enable_vectors(VFIOPCIDevice *vdev, bool msix) static void vfio_add_kvm_msi_virq(VFIOPCIDevice *vdev, VFIOMSIVector *vector, int vector_n, bool msix) { + KVMRouteChange c; int virq; if ((msix && vdev->no_kvm_msix) || (!msix && vdev->no_kvm_msi)) { @@ -422,11 +423,13 @@ static void vfio_add_kvm_msi_virq(VFIOPCIDevice *vdev, VFIOMSIVector *vector, return; } - virq = kvm_irqchip_add_msi_route(kvm_state, vector_n, &vdev->pdev); + c = kvm_irqchip_begin_route_changes(kvm_state); + virq = kvm_irqchip_add_msi_route(&c, vector_n, &vdev->pdev); if (virq < 0) { event_notifier_cleanup(&vector->kvm_interrupt); return; } + kvm_irqchip_commit_route_changes(&c); if (kvm_irqchip_add_irqfd_notifier_gsi(kvm_state, &vector->kvm_interrupt, NULL, virq) < 0) { diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c index 373e26d7c3..80d8c2ea11 100644 --- a/hw/virtio/virtio-pci.c +++ b/hw/virtio/virtio-pci.c @@ -758,10 +758,12 @@ static int kvm_virtio_pci_vq_vector_use(VirtIOPCIProxy *proxy, int ret; if (irqfd->users == 0) { - ret = kvm_irqchip_add_msi_route(kvm_state, vector, &proxy->pci_dev); + KVMRouteChange c = kvm_irqchip_begin_route_changes(kvm_state); + ret = kvm_irqchip_add_msi_route(&c, vector, &proxy->pci_dev); if (ret < 0) { return ret; } + kvm_irqchip_commit_route_changes(&c); irqfd->virq = ret; } irqfd->users++; diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h index 6f8a43dea4..097b3c79d5 100644 --- a/include/sysemu/kvm.h +++ b/include/sysemu/kvm.h @@ -486,7 +486,7 @@ void kvm_init_cpu_signals(CPUState *cpu); /** * kvm_irqchip_add_msi_route - Add MSI route for specific vector - * @s: KVM state + * @c: KVMRouteChange instance. * @vector: which vector to add. This can be either MSI/MSIX * vector. The function will automatically detect whether * MSI/MSIX is enabled, and fetch corresponding MSI @@ -495,7 +495,7 @@ void kvm_init_cpu_signals(CPUState *cpu); * as @NULL, an empty MSI message will be inited. * @return: virq (>=0) when success, errno (<0) when failed. */ -int kvm_irqchip_add_msi_route(KVMState *s, int vector, PCIDevice *dev); +int kvm_irqchip_add_msi_route(KVMRouteChange *c, int vector, PCIDevice *dev); int kvm_irqchip_update_msi_route(KVMState *s, int virq, MSIMessage msg, PCIDevice *dev); void kvm_irqchip_commit_routes(KVMState *s); diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c index 2c8feb4a6f..cfef36a14e 100644 --- a/target/i386/kvm/kvm.c +++ b/target/i386/kvm/kvm.c @@ -4939,16 +4939,18 @@ void kvm_arch_init_irq_routing(KVMState *s) kvm_gsi_routing_allowed = true; if (kvm_irqchip_is_split()) { + KVMRouteChange c = kvm_irqchip_begin_route_changes(s); int i; /* If the ioapic is in QEMU and the lapics are in KVM, reserve MSI routes for signaling interrupts to the local apics. */ for (i = 0; i < IOAPIC_NUM_PINS; i++) { - if (kvm_irqchip_add_msi_route(s, 0, NULL) < 0) { + if (kvm_irqchip_add_msi_route(&c, 0, NULL) < 0) { error_report("Could not enable split IRQ mode."); exit(1); } } + kvm_irqchip_commit_route_changes(&c); } } -- 2.23.0
