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([2a01:e0a:280:24f0:3f78:514a:4f03:fdc0]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-3a35e49262fsm18261125f8f.44.2025.05.21.00.29.30 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 21 May 2025 00:29:31 -0700 (PDT) Message-ID: <19e2b44d-0dcc-424a-904d-a7519e25d93e@redhat.com> Date: Wed, 21 May 2025 09:29:30 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 06/29] vfio: enable per-IRQ MSI-X masking To: John Levon , qemu-devel@nongnu.org Cc: Alex Williamson , Paolo Bonzini , =?UTF-8?Q?Marc-Andr=C3=A9_Lureau?= , Peter Xu , David Hildenbrand , Stefano Garzarella , =?UTF-8?Q?Daniel_P=2E_Berrang=C3=A9?= , =?UTF-8?Q?Philippe_Mathieu-Daud=C3=A9?= , "Michael S. Tsirkin" , Thanos Makatos , John Johnson , Elena Ufimtseva , Jagannathan Raman , Steven Sistare References: <20250520150419.2172078-1-john.levon@nutanix.com> <20250520150419.2172078-7-john.levon@nutanix.com> Content-Language: en-US, fr From: =?UTF-8?Q?C=C3=A9dric_Le_Goater?= Autocrypt: addr=clg@redhat.com; keydata= xsFNBFu8o3UBEADP+oJVJaWm5vzZa/iLgpBAuzxSmNYhURZH+guITvSySk30YWfLYGBWQgeo 8NzNXBY3cH7JX3/a0jzmhDc0U61qFxVgrPqs1PQOjp7yRSFuDAnjtRqNvWkvlnRWLFq4+U5t yzYe4SFMjFb6Oc0xkQmaK2flmiJNnnxPttYwKBPd98WfXMmjwAv7QfwW+OL3VlTPADgzkcqj 53bfZ4VblAQrq6Ctbtu7JuUGAxSIL3XqeQlAwwLTfFGrmpY7MroE7n9Rl+hy/kuIrb/TO8n0 ZxYXvvhT7OmRKvbYuc5Jze6o7op/bJHlufY+AquYQ4dPxjPPVUT/DLiUYJ3oVBWFYNbzfOrV RxEwNuRbycttMiZWxgflsQoHF06q/2l4ttS3zsV4TDZudMq0TbCH/uJFPFsbHUN91qwwaN/+ gy1j7o6aWMz+Ib3O9dK2M/j/O/Ube95mdCqN4N/uSnDlca3YDEWrV9jO1mUS/ndOkjxa34ia 70FjwiSQAsyIwqbRO3CGmiOJqDa9qNvd2TJgAaS2WCw/TlBALjVQ7AyoPEoBPj31K74Wc4GS Rm+FSch32ei61yFu6ACdZ12i5Edt+To+hkElzjt6db/UgRUeKfzlMB7PodK7o8NBD8outJGS tsL2GRX24QvvBuusJdMiLGpNz3uqyqwzC5w0Fd34E6G94806fwARAQABzSJDw6lkcmljIExl IEdvYXRlciA8Y2xnQHJlZGhhdC5jb20+wsGRBBMBCAA7FiEEoPZlSPBIlev+awtgUaNDx8/7 7KEFAmTLlVECGwMFCwkIBwICIgIGFQoJCAsCBBYCAwECHgcCF4AACgkQUaNDx8/77KG0eg// S0zIzTcxkrwJ/9XgdcvVTnXLVF9V4/tZPfB7sCp8rpDCEseU6O0TkOVFoGWM39sEMiQBSvyY lHrP7p7E/JYQNNLh441MfaX8RJ5Ul3btluLapm8oHp/vbHKV2IhLcpNCfAqaQKdfk8yazYhh EdxTBlzxPcu+78uE5fF4wusmtutK0JG0sAgq0mHFZX7qKG6LIbdLdaQalZ8CCFMKUhLptW71 xe+aNrn7hScBoOj2kTDRgf9CE7svmjGToJzUxgeh9mIkxAxTu7XU+8lmL28j2L5uNuDOq9vl hM30OT+pfHmyPLtLK8+GXfFDxjea5hZLF+2yolE/ATQFt9AmOmXC+YayrcO2ZvdnKExZS1o8 VUKpZgRnkwMUUReaF/mTauRQGLuS4lDcI4DrARPyLGNbvYlpmJWnGRWCDguQ/LBPpbG7djoy k3NlvoeA757c4DgCzggViqLm0Bae320qEc6z9o0X0ePqSU2f7vcuWN49Uhox5kM5L86DzjEQ RHXndoJkeL8LmHx8DM+kx4aZt0zVfCHwmKTkSTQoAQakLpLte7tWXIio9ZKhUGPv/eHxXEoS 0rOOAZ6np1U/xNR82QbF9qr9TrTVI3GtVe7Vxmff+qoSAxJiZQCo5kt0YlWwti2fFI4xvkOi V7lyhOA3+/3oRKpZYQ86Frlo61HU3r6d9wzOwU0EW7yjdQEQALyDNNMw/08/fsyWEWjfqVhW pOOrX2h+z4q0lOHkjxi/FRIRLfXeZjFfNQNLSoL8j1y2rQOs1j1g+NV3K5hrZYYcMs0xhmrZ KXAHjjDx7FW3sG3jcGjFW5Xk4olTrZwFsZVUcP8XZlArLmkAX3UyrrXEWPSBJCXxDIW1hzwp bV/nVbo/K9XBptT/wPd+RPiOTIIRptjypGY+S23HYBDND3mtfTz/uY0Jytaio9GETj+fFis6 TxFjjbZNUxKpwftu/4RimZ7qL+uM1rG1lLWc9SPtFxRQ8uLvLOUFB1AqHixBcx7LIXSKZEFU CSLB2AE4wXQkJbApye48qnZ09zc929df5gU6hjgqV9Gk1rIfHxvTsYltA1jWalySEScmr0iS YBZjw8Nbd7SxeomAxzBv2l1Fk8fPzR7M616dtb3Z3HLjyvwAwxtfGD7VnvINPbzyibbe9c6g LxYCr23c2Ry0UfFXh6UKD83d5ybqnXrEJ5n/t1+TLGCYGzF2erVYGkQrReJe8Mld3iGVldB7 JhuAU1+d88NS3aBpNF6TbGXqlXGF6Yua6n1cOY2Yb4lO/mDKgjXd3aviqlwVlodC8AwI0Sdu jWryzL5/AGEU2sIDQCHuv1QgzmKwhE58d475KdVX/3Vt5I9kTXpvEpfW18TjlFkdHGESM/Jx IqVsqvhAJkalABEBAAHCwV8EGAECAAkFAlu8o3UCGwwACgkQUaNDx8/77KEhwg//WqVopd5k 8hQb9VVdk6RQOCTfo6wHhEqgjbXQGlaxKHoXywEQBi8eULbeMQf5l4+tHJWBxswQ93IHBQjK yKyNr4FXseUI5O20XVNYDJZUrhA4yn0e/Af0IX25d94HXQ5sMTWr1qlSK6Zu79lbH3R57w9j hQm9emQEp785ui3A5U2Lqp6nWYWXz0eUZ0Tad2zC71Gg9VazU9MXyWn749s0nXbVLcLS0yop s302Gf3ZmtgfXTX/W+M25hiVRRKCH88yr6it+OMJBUndQVAA/fE9hYom6t/zqA248j0QAV/p LHH3hSirE1mv+7jpQnhMvatrwUpeXrOiEw1nHzWCqOJUZ4SY+HmGFW0YirWV2mYKoaGO2YBU wYF7O9TI3GEEgRMBIRT98fHa0NPwtlTktVISl73LpgVscdW8yg9Gc82oe8FzU1uHjU8b10lU XOMHpqDDEV9//r4ZhkKZ9C4O+YZcTFu+mvAY3GlqivBNkmYsHYSlFsbxc37E1HpTEaSWsGfA HQoPn9qrDJgsgcbBVc1gkUT6hnxShKPp4PlsZVMNjvPAnr5TEBgHkk54HQRhhwcYv1T2QumQ izDiU6iOrUzBThaMhZO3i927SG2DwWDVzZltKrCMD1aMPvb3NU8FOYRhNmIFR3fcalYr+9gD uVKe8BVz4atMOoktmt0GWTOC8P4= In-Reply-To: <20250520150419.2172078-7-john.levon@nutanix.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=170.10.133.124; envelope-from=clg@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -25 X-Spam_score: -2.6 X-Spam_bar: -- X-Spam_report: (-2.6 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.487, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org +Sẗeven On 5/20/25 17:03, John Levon wrote: > If VFIO_IRQ_INFO_MASKABLE is set for VFIO_PCI_MSIX_IRQ_INDEX, record > this in ->can_mask_msix, and use it to individually mask MSI-X > interrupts as needed. > > Originally-by: John Johnson > Signed-off-by: Elena Ufimtseva > Signed-off-by: Jagannathan Raman > Signed-off-by: John Levon This one conflicts with the "live update" series. We will address it later. Thanks, C. > --- > hw/vfio/pci.h | 1 + > include/hw/vfio/vfio-device.h | 2 ++ > hw/vfio/device.c | 26 +++++++++++++++++++ > hw/vfio/pci.c | 47 ++++++++++++++++++++++++++++++----- > 4 files changed, 70 insertions(+), 6 deletions(-) > > diff --git a/hw/vfio/pci.h b/hw/vfio/pci.h > index 61fa385ddb..43c2d72b84 100644 > --- a/hw/vfio/pci.h > +++ b/hw/vfio/pci.h > @@ -191,6 +191,7 @@ struct VFIOPCIDevice { > bool defer_kvm_irq_routing; > bool clear_parent_atomics_on_exit; > bool skip_vsc_check; > + bool can_mask_msix; > VFIODisplay *dpy; > Notifier irqchip_change_notifier; > }; > diff --git a/include/hw/vfio/vfio-device.h b/include/hw/vfio/vfio-device.h > index 8bcb3c19f6..923f9cd116 100644 > --- a/include/hw/vfio/vfio-device.h > +++ b/include/hw/vfio/vfio-device.h > @@ -133,7 +133,9 @@ struct VFIODeviceOps { > (ret < 0 ? strerror(-ret) : "short write") > > void vfio_device_irq_disable(VFIODevice *vbasedev, int index); > +void vfio_device_irq_unmask_single(VFIODevice *vbasedev, int index, int irq); > void vfio_device_irq_unmask(VFIODevice *vbasedev, int index); > +void vfio_device_irq_mask_single(VFIODevice *vbasedev, int index, int irq); > void vfio_device_irq_mask(VFIODevice *vbasedev, int index); > bool vfio_device_irq_set_signaling(VFIODevice *vbasedev, int index, int subindex, > int action, int fd, Error **errp); > diff --git a/hw/vfio/device.c b/hw/vfio/device.c > index 9fba2c7272..d0068086ae 100644 > --- a/hw/vfio/device.c > +++ b/hw/vfio/device.c > @@ -85,6 +85,19 @@ void vfio_device_irq_disable(VFIODevice *vbasedev, int index) > vbasedev->io_ops->set_irqs(vbasedev, &irq_set); > } > > +void vfio_device_irq_unmask_single(VFIODevice *vbasedev, int index, int irq) > +{ > + struct vfio_irq_set irq_set = { > + .argsz = sizeof(irq_set), > + .flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_UNMASK, > + .index = index, > + .start = irq, > + .count = 1, > + }; > + > + vbasedev->io_ops->set_irqs(vbasedev, &irq_set); > +} > + > void vfio_device_irq_unmask(VFIODevice *vbasedev, int index) > { > struct vfio_irq_set irq_set = { > @@ -98,6 +111,19 @@ void vfio_device_irq_unmask(VFIODevice *vbasedev, int index) > vbasedev->io_ops->set_irqs(vbasedev, &irq_set); > } > > +void vfio_device_irq_mask_single(VFIODevice *vbasedev, int index, int irq) > +{ > + struct vfio_irq_set irq_set = { > + .argsz = sizeof(irq_set), > + .flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_MASK, > + .index = index, > + .start = irq, > + .count = 1, > + }; > + > + vbasedev->io_ops->set_irqs(vbasedev, &irq_set); > +} > + > void vfio_device_irq_mask(VFIODevice *vbasedev, int index) > { > struct vfio_irq_set irq_set = { > diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c > index 5159198bdb..ef38b4692a 100644 > --- a/hw/vfio/pci.c > +++ b/hw/vfio/pci.c > @@ -535,6 +535,7 @@ static int vfio_msix_vector_do_use(PCIDevice *pdev, unsigned int nr, > { > VFIOPCIDevice *vdev = VFIO_PCI_BASE(pdev); > VFIOMSIVector *vector; > + bool new_vec = false; > int ret; > bool resizing = !!(vdev->nr_vectors < nr + 1); > > @@ -549,6 +550,7 @@ static int vfio_msix_vector_do_use(PCIDevice *pdev, unsigned int nr, > error_report("vfio: Error: event_notifier_init failed"); > } > vector->use = true; > + new_vec = true; > msix_vector_use(pdev, nr); > } > > @@ -575,6 +577,7 @@ static int vfio_msix_vector_do_use(PCIDevice *pdev, unsigned int nr, > kvm_irqchip_commit_route_changes(&vfio_route_change); > vfio_connect_kvm_msi_virq(vector); > } > + new_vec = true; > } > } > > @@ -584,6 +587,9 @@ static int vfio_msix_vector_do_use(PCIDevice *pdev, unsigned int nr, > * in use, so we shutdown and incrementally increase them as needed. > * nr_vectors represents the total number of vectors allocated. > * > + * Otherwise, unmask the vector if the vector is already setup (and we can > + * do so) or send the fd if not. > + * > * When dynamic allocation is supported, let the host only allocate > * and enable a vector when it is in use in guest. nr_vectors represents > * the upper bound of vectors being enabled (but not all of the ranges > @@ -594,13 +600,20 @@ static int vfio_msix_vector_do_use(PCIDevice *pdev, unsigned int nr, > } > > if (!vdev->defer_kvm_irq_routing) { > - if (vdev->msix->noresize && resizing) { > - vfio_device_irq_disable(&vdev->vbasedev, VFIO_PCI_MSIX_IRQ_INDEX); > - ret = vfio_enable_vectors(vdev, true); > - if (ret) { > - error_report("vfio: failed to enable vectors, %s", > - strerror(-ret)); > + if (resizing) { > + if (vdev->msix->noresize) { > + vfio_device_irq_disable(&vdev->vbasedev, > + VFIO_PCI_MSIX_IRQ_INDEX); > + ret = vfio_enable_vectors(vdev, true); > + if (ret) { > + error_report("vfio: failed to enable vectors, %d", ret); > + } > + } else { > + set_irq_signalling(&vdev->vbasedev, vector, nr); > } > + } else if (vdev->can_mask_msix && !new_vec) { > + vfio_device_irq_unmask_single(&vdev->vbasedev, > + VFIO_PCI_MSIX_IRQ_INDEX, nr); > } else { > set_irq_signalling(&vdev->vbasedev, vector, nr); > } > @@ -630,6 +643,13 @@ static void vfio_msix_vector_release(PCIDevice *pdev, unsigned int nr) > > trace_vfio_msix_vector_release(vdev->vbasedev.name, nr); > > + /* just mask vector if peer supports it */ > + if (vdev->can_mask_msix) { > + vfio_device_irq_mask_single(&vdev->vbasedev, VFIO_PCI_MSIX_IRQ_INDEX, > + nr); > + return; > + } > + > /* > * There are still old guests that mask and unmask vectors on every > * interrupt. If we're using QEMU bypass with a KVM irqfd, leave all of > @@ -702,6 +722,13 @@ static void vfio_msix_enable(VFIOPCIDevice *vdev) > error_report("vfio: failed to enable vectors, %s", > strerror(-ret)); > } > + } else if (vdev->can_mask_msix) { > + /* > + * If we can use single irq masking, send an invalid fd on vector 0 > + * to enable MSI-X without any vectors enabled. > + */ > + vfio_device_irq_set_signaling(&vdev->vbasedev, VFIO_PCI_MSIX_IRQ_INDEX, > + 0, VFIO_IRQ_SET_ACTION_TRIGGER, -1, NULL); > } else { > /* > * Some communication channels between VF & PF or PF & fw rely on the > @@ -2842,6 +2869,14 @@ bool vfio_pci_populate_device(VFIOPCIDevice *vdev, Error **errp) > } > } > > + ret = vfio_device_get_irq_info(vbasedev, VFIO_PCI_MSIX_IRQ_INDEX, > + &irq_info); > + if (ret == 0 && (irq_info.flags & VFIO_IRQ_INFO_MASKABLE)) { > + vdev->can_mask_msix = true; > + } else { > + vdev->can_mask_msix = false; > + } > + > ret = vfio_device_get_irq_info(vbasedev, VFIO_PCI_ERR_IRQ_INDEX, &irq_info); > if (ret) { > /* This can fail for an old kernel or legacy PCI dev */