1. 09 1月, 2016 8 次提交
  2. 17 12月, 2015 4 次提交
    • A
      kvm/x86: Remove Hyper-V SynIC timer stopping · 481d2bcc
      Andrey Smetanin 提交于
      It's possible that guest send us Hyper-V EOM at the middle
      of Hyper-V SynIC timer running, so we start processing of Hyper-V
      SynIC timers in vcpu context and stop the Hyper-V SynIC timer
      unconditionally:
      
          host                                       guest
          ------------------------------------------------------------------------------
                                                 start periodic stimer
          start periodic timer
          timer expires after 15ms
          send expiration message into guest
          restart periodic timer
          timer expires again after 15 ms
          msg slot is still not cleared so
          setup ->msg_pending
      (1) restart periodic timer
                                                 process timer msg and clear slot
                                                 ->msg_pending was set:
                                                     send EOM into host
          received EOM
            kvm_make_request(KVM_REQ_HV_STIMER)
      
          kvm_hv_process_stimers():
              ...
              stimer_stop()
              if (time_now >= stimer->exp_time)
                      stimer_expiration(stimer);
      
      Because the timer was rearmed at (1), time_now < stimer->exp_time
      and stimer_expiration is not called.  The timer then never fires.
      
      The patch fixes such situation by not stopping Hyper-V SynIC timer
      at all, because it's safe to restart it without stop in vcpu context
      and timer callback always returns HRTIMER_NORESTART.
      Signed-off-by: NAndrey Smetanin <asmetanin@virtuozzo.com>
      CC: Gleb Natapov <gleb@kernel.org>
      CC: Paolo Bonzini <pbonzini@redhat.com>
      CC: Roman Kagan <rkagan@virtuozzo.com>
      CC: Denis V. Lunev <den@openvz.org>
      CC: qemu-devel@nongnu.org
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      481d2bcc
    • A
      kvm/x86: Hyper-V SynIC timers · 1f4b34f8
      Andrey Smetanin 提交于
      Per Hyper-V specification (and as required by Hyper-V-aware guests),
      SynIC provides 4 per-vCPU timers.  Each timer is programmed via a pair
      of MSRs, and signals expiration by delivering a special format message
      to the configured SynIC message slot and triggering the corresponding
      synthetic interrupt.
      
      Note: as implemented by this patch, all periodic timers are "lazy"
      (i.e. if the vCPU wasn't scheduled for more than the timer period the
      timer events are lost), regardless of the corresponding configuration
      MSR.  If deemed necessary, the "catch up" mode (the timer period is
      shortened until the timer catches up) will be implemented later.
      
      Changes v2:
      * Use remainder to calculate periodic timer expiration time
      Signed-off-by: NAndrey Smetanin <asmetanin@virtuozzo.com>
      Reviewed-by: NRoman Kagan <rkagan@virtuozzo.com>
      CC: Gleb Natapov <gleb@kernel.org>
      CC: Paolo Bonzini <pbonzini@redhat.com>
      CC: "K. Y. Srinivasan" <kys@microsoft.com>
      CC: Haiyang Zhang <haiyangz@microsoft.com>
      CC: Vitaly Kuznetsov <vkuznets@redhat.com>
      CC: Roman Kagan <rkagan@virtuozzo.com>
      CC: Denis V. Lunev <den@openvz.org>
      CC: qemu-devel@nongnu.org
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      1f4b34f8
    • A
      kvm/x86: Hyper-V SynIC message slot pending clearing at SINT ack · 765eaa0f
      Andrey Smetanin 提交于
      The SynIC message protocol mandates that the message slot is claimed
      by atomically setting message type to something other than HVMSG_NONE.
      If another message is to be delivered while the slot is still busy,
      message pending flag is asserted to indicate to the guest that the
      hypervisor wants to be notified when the slot is released.
      
      To make sure the protocol works regardless of where the message
      sources are (kernel or userspace), clear the pending flag on SINT ACK
      notification, and let the message sources compete for the slot again.
      Signed-off-by: NAndrey Smetanin <asmetanin@virtuozzo.com>
      Reviewed-by: NRoman Kagan <rkagan@virtuozzo.com>
      CC: Gleb Natapov <gleb@kernel.org>
      CC: Paolo Bonzini <pbonzini@redhat.com>
      CC: "K. Y. Srinivasan" <kys@microsoft.com>
      CC: Haiyang Zhang <haiyangz@microsoft.com>
      CC: Vitaly Kuznetsov <vkuznets@redhat.com>
      CC: Roman Kagan <rkagan@virtuozzo.com>
      CC: Denis V. Lunev <den@openvz.org>
      CC: qemu-devel@nongnu.org
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      765eaa0f
    • A
      kvm/x86: Hyper-V internal helper to read MSR HV_X64_MSR_TIME_REF_COUNT · 93bf4172
      Andrey Smetanin 提交于
      This helper will be used also in Hyper-V SynIC timers implementation.
      Signed-off-by: NAndrey Smetanin <asmetanin@virtuozzo.com>
      Reviewed-by: NRoman Kagan <rkagan@virtuozzo.com>
      CC: Gleb Natapov <gleb@kernel.org>
      CC: Paolo Bonzini <pbonzini@redhat.com>
      CC: "K. Y. Srinivasan" <kys@microsoft.com>
      CC: Haiyang Zhang <haiyangz@microsoft.com>
      CC: Vitaly Kuznetsov <vkuznets@redhat.com>
      CC: Roman Kagan <rkagan@virtuozzo.com>
      CC: Denis V. Lunev <den@openvz.org>
      CC: qemu-devel@nongnu.org
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      93bf4172
  3. 26 11月, 2015 2 次提交
    • A
      kvm/x86: Hyper-V kvm exit · db397571
      Andrey Smetanin 提交于
      A new vcpu exit is introduced to notify the userspace of the
      changes in Hyper-V SynIC configuration triggered by guest writing to the
      corresponding MSRs.
      
      Changes v4:
      * exit into userspace only if guest writes into SynIC MSR's
      
      Changes v3:
      * added KVM_EXIT_HYPERV types and structs notes into docs
      Signed-off-by: NAndrey Smetanin <asmetanin@virtuozzo.com>
      Reviewed-by: NRoman Kagan <rkagan@virtuozzo.com>
      Signed-off-by: NDenis V. Lunev <den@openvz.org>
      CC: Gleb Natapov <gleb@kernel.org>
      CC: Paolo Bonzini <pbonzini@redhat.com>
      CC: Roman Kagan <rkagan@virtuozzo.com>
      CC: Denis V. Lunev <den@openvz.org>
      CC: qemu-devel@nongnu.org
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      db397571
    • A
      kvm/x86: Hyper-V synthetic interrupt controller · 5c919412
      Andrey Smetanin 提交于
      SynIC (synthetic interrupt controller) is a lapic extension,
      which is controlled via MSRs and maintains for each vCPU
       - 16 synthetic interrupt "lines" (SINT's); each can be configured to
         trigger a specific interrupt vector optionally with auto-EOI
         semantics
       - a message page in the guest memory with 16 256-byte per-SINT message
         slots
       - an event flag page in the guest memory with 16 2048-bit per-SINT
         event flag areas
      
      The host triggers a SINT whenever it delivers a new message to the
      corresponding slot or flips an event flag bit in the corresponding area.
      The guest informs the host that it can try delivering a message by
      explicitly asserting EOI in lapic or writing to End-Of-Message (EOM)
      MSR.
      
      The userspace (qemu) triggers interrupts and receives EOM notifications
      via irqfd with resampler; for that, a GSI is allocated for each
      configured SINT, and irq_routing api is extended to support GSI-SINT
      mapping.
      
      Changes v4:
      * added activation of SynIC by vcpu KVM_ENABLE_CAP
      * added per SynIC active flag
      * added deactivation of APICv upon SynIC activation
      
      Changes v3:
      * added KVM_CAP_HYPERV_SYNIC and KVM_IRQ_ROUTING_HV_SINT notes into
      docs
      
      Changes v2:
      * do not use posted interrupts for Hyper-V SynIC AutoEOI vectors
      * add Hyper-V SynIC vectors into EOI exit bitmap
      * Hyper-V SyniIC SINT msr write logic simplified
      Signed-off-by: NAndrey Smetanin <asmetanin@virtuozzo.com>
      Reviewed-by: NRoman Kagan <rkagan@virtuozzo.com>
      Signed-off-by: NDenis V. Lunev <den@openvz.org>
      CC: Gleb Natapov <gleb@kernel.org>
      CC: Paolo Bonzini <pbonzini@redhat.com>
      CC: Roman Kagan <rkagan@virtuozzo.com>
      CC: Denis V. Lunev <den@openvz.org>
      CC: qemu-devel@nongnu.org
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      5c919412
  4. 01 10月, 2015 2 次提交
  5. 23 7月, 2015 2 次提交