On Fri, Feb 14, 2025 at 05:29:34PM +0100, Peter Krempa wrote:
The first part of the series refactors the existing code for reuse and then uses the new helpers to implement the feature.
Note that this series is in RFC state as the qemu patches are still being discussed. Thus also the capability bump is not final.
Also note that we should discuss the libvirt interface perhaps as it turns out that 'virtio-scsi' has two internal queues that need to be mapped as well.
For now I've solved this administratively by instructing users to also add mapping for queue '0' and '1' which are the special ones in case of virtio-scsi.
Thanks for tackling this upcoming QEMU feature! I thought about the pros/cons of exposing all virtqueues in iothread-vq-mapping= whereas just the command virtqueues are exposed by num_queues=. Although it's confusing and inconvenient that the implicit ctrl and event virtqueues need to be covered by iothread-vq-mapping= but are not counted in num_queues=, I'd rather not introduce magic to hide this detail. If users do need to control these virtqueues explicitly then the magic will get in the way. Does anyone have a different opinion? Stefan
qemu-patches: https://mail.gnu.org/archive/html/qemu-devel/2025-02/msg02810.html
Peter Krempa (13): conf: Rename 'virDomainDiskIothreadDef' to 'virDomainIothreadMappingDef' conf: domain: Extract code for parsing and formatting iotrhead mapping definition hypervisor: domain: Extract code for checking iothread usage qemu: command: Rename 'qemuBuildDiskDeviceIothreadMappingProps' to 'qemuBuildIothreadMappingProps' qemu: validate: Extract iothread mapping validation code qemuValidateCheckSCSIControllerIOThreads: Return '0' and '-1' instead of bools conf: schemas: Rename 'diskDriverIothreads' to 'iothreadMapping' conf: Validate that iohtreads are used only with 'virtio-scsi' controllers qemucapabilitiestest: Update 'caps_10.0.0_x86_64' to XXXXXX qemu: capabilities: Introduce QEMU_CAPS_VIRTIO_SCSI_IOTHREAD_MAPPING conf: Add support for iothread to queue mapping config for 'virtio-scsi' qemu: Implement support for iothread <-> virtqueue mapping for 'virtio-scsi' controllers qemuxmlconftest: Add 'iothreads-virtio-scsi-mapping' case
docs/formatdomain.rst | 33 +++ src/conf/domain_conf.c | 157 +++++++----- src/conf/domain_conf.h | 11 +- src/conf/domain_validate.c | 19 ++ src/conf/schemas/domaincommon.rng | 7 +- src/hypervisor/domain_driver.c | 34 +-- src/qemu/qemu_capabilities.c | 2 + src/qemu/qemu_capabilities.h | 1 + src/qemu/qemu_command.c | 12 +- src/qemu/qemu_domain.c | 4 +- src/qemu/qemu_validate.c | 234 ++++++++++-------- .../caps_10.0.0_x86_64.replies | 12 +- .../caps_10.0.0_x86_64.xml | 3 +- ...r-virtio-serial-iothread.x86_64-latest.err | 1 + .../controller-virtio-serial-iothread.xml | 27 ++ ...ads-virtio-scsi-mapping.x86_64-latest.args | 39 +++ ...eads-virtio-scsi-mapping.x86_64-latest.xml | 54 ++++ .../iothreads-virtio-scsi-mapping.xml | 46 ++++ tests/qemuxmlconftest.c | 3 + 19 files changed, 506 insertions(+), 193 deletions(-) create mode 100644 tests/qemuxmlconfdata/controller-virtio-serial-iothread.x86_64-latest.err create mode 100644 tests/qemuxmlconfdata/controller-virtio-serial-iothread.xml create mode 100644 tests/qemuxmlconfdata/iothreads-virtio-scsi-mapping.x86_64-latest.args create mode 100644 tests/qemuxmlconfdata/iothreads-virtio-scsi-mapping.x86_64-latest.xml create mode 100644 tests/qemuxmlconfdata/iothreads-virtio-scsi-mapping.xml
-- 2.48.1