From bd36adb8df5d62a2b4d4ded6357fb50b69a508fa Mon Sep 17 00:00:00 2001 From: Jagannathan Raman Date: Fri, 29 Jan 2021 11:46:19 -0500 Subject: multi-process: create IOHUB object to handle irq IOHUB object is added to manage PCI IRQs. It uses KVM_IRQFD ioctl to create irqfd to injecting PCI interrupts to the guest. IOHUB object forwards the irqfd to the remote process. Remote process uses this fd to directly send interrupts to the guest, bypassing QEMU. Signed-off-by: John G Johnson Signed-off-by: Jagannathan Raman Signed-off-by: Elena Ufimtseva Reviewed-by: Stefan Hajnoczi Message-id: 51d5c3d54e28a68b002e3875c59599c9f5a424a1.1611938319.git.jag.raman@oracle.com Signed-off-by: Stefan Hajnoczi --- hw/remote/iohub.c | 119 ++++++++++++++++++++++++++++++++++++++++++++++++ hw/remote/machine.c | 10 ++++ hw/remote/meson.build | 1 + hw/remote/message.c | 4 ++ hw/remote/mpqemu-link.c | 5 ++ hw/remote/proxy.c | 56 +++++++++++++++++++++++ 6 files changed, 195 insertions(+) create mode 100644 hw/remote/iohub.c (limited to 'hw/remote') diff --git a/hw/remote/iohub.c b/hw/remote/iohub.c new file mode 100644 index 0000000000..e4ff131a6b --- /dev/null +++ b/hw/remote/iohub.c @@ -0,0 +1,119 @@ +/* + * Remote IO Hub + * + * Copyright © 2018, 2021 Oracle and/or its affiliates. + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + * + */ + +#include "qemu/osdep.h" +#include "qemu-common.h" + +#include "hw/pci/pci.h" +#include "hw/pci/pci_ids.h" +#include "hw/pci/pci_bus.h" +#include "qemu/thread.h" +#include "hw/boards.h" +#include "hw/remote/machine.h" +#include "hw/remote/iohub.h" +#include "qemu/main-loop.h" + +void remote_iohub_init(RemoteIOHubState *iohub) +{ + int pirq; + + memset(&iohub->irqfds, 0, sizeof(iohub->irqfds)); + memset(&iohub->resamplefds, 0, sizeof(iohub->resamplefds)); + + for (pirq = 0; pirq < REMOTE_IOHUB_NB_PIRQS; pirq++) { + qemu_mutex_init(&iohub->irq_level_lock[pirq]); + iohub->irq_level[pirq] = 0; + event_notifier_init_fd(&iohub->irqfds[pirq], -1); + event_notifier_init_fd(&iohub->resamplefds[pirq], -1); + } +} + +void remote_iohub_finalize(RemoteIOHubState *iohub) +{ + int pirq; + + for (pirq = 0; pirq < REMOTE_IOHUB_NB_PIRQS; pirq++) { + qemu_set_fd_handler(event_notifier_get_fd(&iohub->resamplefds[pirq]), + NULL, NULL, NULL); + event_notifier_cleanup(&iohub->irqfds[pirq]); + event_notifier_cleanup(&iohub->resamplefds[pirq]); + qemu_mutex_destroy(&iohub->irq_level_lock[pirq]); + } +} + +int remote_iohub_map_irq(PCIDevice *pci_dev, int intx) +{ + return pci_dev->devfn; +} + +void remote_iohub_set_irq(void *opaque, int pirq, int level) +{ + RemoteIOHubState *iohub = opaque; + + assert(pirq >= 0); + assert(pirq < PCI_DEVFN_MAX); + + QEMU_LOCK_GUARD(&iohub->irq_level_lock[pirq]); + + if (level) { + if (++iohub->irq_level[pirq] == 1) { + event_notifier_set(&iohub->irqfds[pirq]); + } + } else if (iohub->irq_level[pirq] > 0) { + iohub->irq_level[pirq]--; + } +} + +static void intr_resample_handler(void *opaque) +{ + ResampleToken *token = opaque; + RemoteIOHubState *iohub = token->iohub; + int pirq, s; + + pirq = token->pirq; + + s = event_notifier_test_and_clear(&iohub->resamplefds[pirq]); + + assert(s >= 0); + + QEMU_LOCK_GUARD(&iohub->irq_level_lock[pirq]); + + if (iohub->irq_level[pirq]) { + event_notifier_set(&iohub->irqfds[pirq]); + } +} + +void process_set_irqfd_msg(PCIDevice *pci_dev, MPQemuMsg *msg) +{ + RemoteMachineState *machine = REMOTE_MACHINE(current_machine); + RemoteIOHubState *iohub = &machine->iohub; + int pirq, intx; + + intx = pci_get_byte(pci_dev->config + PCI_INTERRUPT_PIN) - 1; + + pirq = remote_iohub_map_irq(pci_dev, intx); + + if (event_notifier_get_fd(&iohub->irqfds[pirq]) != -1) { + qemu_set_fd_handler(event_notifier_get_fd(&iohub->resamplefds[pirq]), + NULL, NULL, NULL); + event_notifier_cleanup(&iohub->irqfds[pirq]); + event_notifier_cleanup(&iohub->resamplefds[pirq]); + memset(&iohub->token[pirq], 0, sizeof(ResampleToken)); + } + + event_notifier_init_fd(&iohub->irqfds[pirq], msg->fds[0]); + event_notifier_init_fd(&iohub->resamplefds[pirq], msg->fds[1]); + + iohub->token[pirq].iohub = iohub; + iohub->token[pirq].pirq = pirq; + + qemu_set_fd_handler(msg->fds[1], intr_resample_handler, NULL, + &iohub->token[pirq]); +} diff --git a/hw/remote/machine.c b/hw/remote/machine.c index 9519a6c0a4..c0ab4f528a 100644 --- a/hw/remote/machine.c +++ b/hw/remote/machine.c @@ -20,12 +20,15 @@ #include "exec/address-spaces.h" #include "exec/memory.h" #include "qapi/error.h" +#include "hw/pci/pci_host.h" +#include "hw/remote/iohub.h" static void remote_machine_init(MachineState *machine) { MemoryRegion *system_memory, *system_io, *pci_memory; RemoteMachineState *s = REMOTE_MACHINE(machine); RemotePCIHost *rem_host; + PCIHostState *pci_host; system_memory = get_system_memory(); system_io = get_system_io(); @@ -45,6 +48,13 @@ static void remote_machine_init(MachineState *machine) memory_region_add_subregion_overlap(system_memory, 0x0, pci_memory, -1); qdev_realize(DEVICE(rem_host), sysbus_get_default(), &error_fatal); + + pci_host = PCI_HOST_BRIDGE(rem_host); + + remote_iohub_init(&s->iohub); + + pci_bus_irqs(pci_host->bus, remote_iohub_set_irq, remote_iohub_map_irq, + &s->iohub, REMOTE_IOHUB_NB_PIRQS); } static void remote_machine_class_init(ObjectClass *oc, void *data) diff --git a/hw/remote/meson.build b/hw/remote/meson.build index 7f11be4736..e6a5574242 100644 --- a/hw/remote/meson.build +++ b/hw/remote/meson.build @@ -5,6 +5,7 @@ remote_ss.add(when: 'CONFIG_MULTIPROCESS', if_true: files('mpqemu-link.c')) remote_ss.add(when: 'CONFIG_MULTIPROCESS', if_true: files('message.c')) remote_ss.add(when: 'CONFIG_MULTIPROCESS', if_true: files('remote-obj.c')) remote_ss.add(when: 'CONFIG_MULTIPROCESS', if_true: files('proxy.c')) +remote_ss.add(when: 'CONFIG_MULTIPROCESS', if_true: files('iohub.c')) specific_ss.add(when: 'CONFIG_MULTIPROCESS', if_true: files('memory.c')) specific_ss.add(when: 'CONFIG_MULTIPROCESS', if_true: files('proxy-memory-listener.c')) diff --git a/hw/remote/message.c b/hw/remote/message.c index 25341d8ad2..adab040ca1 100644 --- a/hw/remote/message.c +++ b/hw/remote/message.c @@ -18,6 +18,7 @@ #include "hw/pci/pci.h" #include "exec/memattrs.h" #include "hw/remote/memory.h" +#include "hw/remote/iohub.h" static void process_config_write(QIOChannel *ioc, PCIDevice *dev, MPQemuMsg *msg, Error **errp); @@ -65,6 +66,9 @@ void coroutine_fn mpqemu_remote_msg_loop_co(void *data) case MPQEMU_CMD_SYNC_SYSMEM: remote_sysmem_reconfig(&msg, &local_err); break; + case MPQEMU_CMD_SET_IRQFD: + process_set_irqfd_msg(pci_dev, &msg); + break; default: error_setg(&local_err, "Unknown command (%d) received for device %s" diff --git a/hw/remote/mpqemu-link.c b/hw/remote/mpqemu-link.c index 52bfeddcdc..9ce31526e8 100644 --- a/hw/remote/mpqemu-link.c +++ b/hw/remote/mpqemu-link.c @@ -254,6 +254,11 @@ bool mpqemu_msg_valid(MPQemuMsg *msg) return false; } break; + case MPQEMU_CMD_SET_IRQFD: + if (msg->size || (msg->num_fds != 2)) { + return false; + } + break; default: break; } diff --git a/hw/remote/proxy.c b/hw/remote/proxy.c index 472b2df335..555b3103f4 100644 --- a/hw/remote/proxy.c +++ b/hw/remote/proxy.c @@ -21,6 +21,57 @@ #include "qemu/error-report.h" #include "hw/remote/proxy-memory-listener.h" #include "qom/object.h" +#include "qemu/event_notifier.h" +#include "sysemu/kvm.h" +#include "util/event_notifier-posix.c" + +static void proxy_intx_update(PCIDevice *pci_dev) +{ + PCIProxyDev *dev = PCI_PROXY_DEV(pci_dev); + PCIINTxRoute route; + int pin = pci_get_byte(pci_dev->config + PCI_INTERRUPT_PIN) - 1; + + if (dev->virq != -1) { + kvm_irqchip_remove_irqfd_notifier_gsi(kvm_state, &dev->intr, dev->virq); + dev->virq = -1; + } + + route = pci_device_route_intx_to_irq(pci_dev, pin); + + dev->virq = route.irq; + + if (dev->virq != -1) { + kvm_irqchip_add_irqfd_notifier_gsi(kvm_state, &dev->intr, + &dev->resample, dev->virq); + } +} + +static void setup_irqfd(PCIProxyDev *dev) +{ + PCIDevice *pci_dev = PCI_DEVICE(dev); + MPQemuMsg msg; + Error *local_err = NULL; + + event_notifier_init(&dev->intr, 0); + event_notifier_init(&dev->resample, 0); + + memset(&msg, 0, sizeof(MPQemuMsg)); + msg.cmd = MPQEMU_CMD_SET_IRQFD; + msg.num_fds = 2; + msg.fds[0] = event_notifier_get_fd(&dev->intr); + msg.fds[1] = event_notifier_get_fd(&dev->resample); + msg.size = 0; + + if (!mpqemu_msg_send(&msg, dev->ioc, &local_err)) { + error_report_err(local_err); + } + + dev->virq = -1; + + proxy_intx_update(pci_dev); + + pci_device_set_intx_routing_notifier(pci_dev, proxy_intx_update); +} static void pci_proxy_dev_realize(PCIDevice *device, Error **errp) { @@ -56,6 +107,8 @@ static void pci_proxy_dev_realize(PCIDevice *device, Error **errp) qio_channel_set_blocking(dev->ioc, true, NULL); proxy_memory_listener_configure(&dev->proxy_listener, dev->ioc); + + setup_irqfd(dev); } static void pci_proxy_dev_exit(PCIDevice *pdev) @@ -71,6 +124,9 @@ static void pci_proxy_dev_exit(PCIDevice *pdev) error_free(dev->migration_blocker); proxy_memory_listener_deconfigure(&dev->proxy_listener); + + event_notifier_cleanup(&dev->intr); + event_notifier_cleanup(&dev->resample); } static void config_op_send(PCIProxyDev *pdev, uint32_t addr, uint32_t *val, -- cgit v1.2.3