Message-ID: <6041f49f-08f9-5cb6-0bc9-070f80f3284f@linux.ibm.com>
Date:   Tue, 7 Dec 2021 16:16:46 -0500
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Subject: Re: [PATCH 00/32] KVM: s390: enable zPCI for interpretive execution
Content-Language: en-US
From:   Matthew Rosato <mjrosato@linux.ibm.com>
To:     linux-s390@vger.kernel.org
Cc:     alex.williamson@redhat.com, cohuck@redhat.com,
        schnelle@linux.ibm.com, farman@linux.ibm.com, pmorel@linux.ibm.com,
        borntraeger@linux.ibm.com, hca@linux.ibm.com, gor@linux.ibm.com,
        gerald.schaefer@linux.ibm.com, agordeev@linux.ibm.com,
        frankja@linux.ibm.com, david@redhat.com, imbrenda@linux.ibm.com,
        vneethv@linux.ibm.com, oberpar@linux.ibm.com, freude@linux.ibm.com,
        thuth@redhat.com, pasic@linux.ibm.com, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20211207205743.150299-1-mjrosato@linux.ibm.com>
In-Reply-To: <20211207205743.150299-1-mjrosato@linux.ibm.com>
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On 12/7/21 3:57 PM, Matthew Rosato wrote:
> Enable interpretive execution of zPCI instructions + adapter interruption
> forwarding for s390x KVM vfio-pci.  This is done by introducing a series
> of new vfio-pci feature ioctls that are unique vfio-pci-zdev (s390x) and
> are used to negotiate the various aspects of zPCI interpretation setup.
> By allowing intepretation of zPCI instructions and firmware delivery of
> interrupts to guests, we can significantly reduce the frequency of guest
> SIE exits for zPCI.  We then see additional gains by handling a hot-path
> instruction that can still intercept to the hypervisor (RPCIT) directly
> in kvm.
> 
>  From the perspective of guest configuration, you passthrough zPCI devices
> in the same manner as before, with intepretation support being used by
> default if available in kernel+qemu.
> 
> Will reply with a link to the associated QEMU series.

https://lists.gnu.org/archive/html/qemu-devel/2021-12/msg00873.html

> 
> Matthew Rosato (32):
>    s390/sclp: detect the zPCI interpretation facility
>    s390/sclp: detect the AISII facility
>    s390/sclp: detect the AENI facility
>    s390/sclp: detect the AISI facility
>    s390/airq: pass more TPI info to airq handlers
>    s390/airq: allow for airq structure that uses an input vector
>    s390/pci: externalize the SIC operation controls and routine
>    s390/pci: stash associated GISA designation
>    s390/pci: export some routines related to RPCIT processing
>    s390/pci: stash dtsm and maxstbl
>    s390/pci: add helper function to find device by handle
>    s390/pci: get SHM information from list pci
>    KVM: s390: pci: add basic kvm_zdev structure
>    KVM: s390: pci: do initial setup for AEN interpretation
>    KVM: s390: pci: enable host forwarding of Adapter Event Notifications
>    KVM: s390: expose the guest zPCI interpretation facility
>    KVM: s390: expose the guest Adapter Interruption Source ID facility
>    KVM: s390: expose guest Adapter Event Notification Interpretation
>      facility
>    KVM: s390: mechanism to enable guest zPCI Interpretation
>    KVM: s390: pci: provide routines for enabling/disabling interpretation
>    KVM: s390: pci: provide routines for enabling/disabling interrupt
>      forwarding
>    KVM: s390: pci: provide routines for enabling/disabling IOAT assist
>    KVM: s390: pci: handle refresh of PCI translations
>    KVM: s390: intercept the rpcit instruction
>    vfio/pci: re-introduce CONFIG_VFIO_PCI_ZDEV
>    vfio-pci/zdev: wire up group notifier
>    vfio-pci/zdev: wire up zPCI interpretive execution support
>    vfio-pci/zdev: wire up zPCI adapter interrupt forwarding support
>    vfio-pci/zdev: wire up zPCI IOAT assist support
>    vfio-pci/zdev: add DTSM to clp group capability
>    KVM: s390: introduce CPU feature for zPCI Interpretation
>    MAINTAINERS: additional files related kvm s390 pci passthrough
> 
>   MAINTAINERS                      |   2 +
>   arch/s390/include/asm/airq.h     |   7 +-
>   arch/s390/include/asm/kvm_host.h |   5 +
>   arch/s390/include/asm/kvm_pci.h  |  62 +++
>   arch/s390/include/asm/pci.h      |  13 +
>   arch/s390/include/asm/pci_clp.h  |  11 +-
>   arch/s390/include/asm/pci_dma.h  |   3 +
>   arch/s390/include/asm/pci_insn.h |  29 +-
>   arch/s390/include/asm/sclp.h     |   4 +
>   arch/s390/include/asm/tpi.h      |  14 +
>   arch/s390/include/uapi/asm/kvm.h |   1 +
>   arch/s390/kvm/Makefile           |   2 +-
>   arch/s390/kvm/interrupt.c        |  97 +++-
>   arch/s390/kvm/kvm-s390.c         |  65 ++-
>   arch/s390/kvm/kvm-s390.h         |  10 +
>   arch/s390/kvm/pci.c              | 784 +++++++++++++++++++++++++++++++
>   arch/s390/kvm/pci.h              |  59 +++
>   arch/s390/kvm/priv.c             |  41 ++
>   arch/s390/pci/pci.c              |  47 ++
>   arch/s390/pci/pci_clp.c          |  19 +-
>   arch/s390/pci/pci_dma.c          |   1 +
>   arch/s390/pci/pci_insn.c         |   5 +-
>   arch/s390/pci/pci_irq.c          |  50 +-
>   drivers/s390/char/sclp_early.c   |   4 +
>   drivers/s390/cio/airq.c          |  12 +-
>   drivers/s390/cio/qdio_thinint.c  |   6 +-
>   drivers/s390/crypto/ap_bus.c     |   9 +-
>   drivers/s390/virtio/virtio_ccw.c |   6 +-
>   drivers/vfio/pci/Kconfig         |  11 +
>   drivers/vfio/pci/Makefile        |   2 +-
>   drivers/vfio/pci/vfio_pci_core.c |   8 +
>   drivers/vfio/pci/vfio_pci_zdev.c | 292 +++++++++++-
>   include/linux/vfio_pci_core.h    |  44 +-
>   include/uapi/linux/vfio.h        |  22 +
>   include/uapi/linux/vfio_zdev.h   |  51 ++
>   35 files changed, 1738 insertions(+), 60 deletions(-)
>   create mode 100644 arch/s390/include/asm/kvm_pci.h
>   create mode 100644 arch/s390/kvm/pci.c
>   create mode 100644 arch/s390/kvm/pci.h
>