similar to: [PATCHv5 08/13] qemu: add support for resizing regions

This adds MSI-X support infrastructure and uses that to enable MSI-X support in virtio net device. Also add a global option to disable MSI-X. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- Makefile.target | 2 +- hw/device-assignment.c | 2 + hw/msix.c | 447 ++++++++++++++++++++++++++++++++++++++++++++++++ hw/msix.h | 38 ++++ hw/pci.c

This adds MSI-X support infrastructure and uses that to enable MSI-X support in virtio net device. Also add a global option to disable MSI-X. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- Makefile.target | 2 +- hw/device-assignment.c | 2 + hw/msix.c | 447 ++++++++++++++++++++++++++++++++++++++++++++++++ hw/msix.h | 38 ++++ hw/pci.c

Here's the latest draft of virtio patches. This is on top of Rusty's recent virtqueue list + name patch. Michael S. Tsirkin (3): virtio: find_vqs/del_vqs virtio operations virtio_pci: split up vp_interrupt virtio_pci: optional MSI-X support drivers/block/virtio_blk.c | 6 +- drivers/char/hw_random/virtio-rng.c | 6 +- drivers/char/virtio_console.c | 26 ++--

Here's the latest draft of virtio patches. This is on top of Rusty's recent virtqueue list + name patch. Michael S. Tsirkin (3): virtio: find_vqs/del_vqs virtio operations virtio_pci: split up vp_interrupt virtio_pci: optional MSI-X support drivers/block/virtio_blk.c | 6 +- drivers/char/hw_random/virtio-rng.c | 6 +- drivers/char/virtio_console.c | 26 ++--

This reorganizes virtio-pci code in vp_interrupt slightly, so that it's easier to add per-vq MSI support on top. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/virtio/virtio_pci.c | 53 +++++++++++++++++++++++++++--------------- 1 files changed, 34 insertions(+), 19 deletions(-) diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c index

This reorganizes virtio-pci code in vp_interrupt slightly, so that it's easier to add per-vq MSI support on top. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/virtio/virtio_pci.c | 53 +++++++++++++++++++++++++++--------------- 1 files changed, 34 insertions(+), 19 deletions(-) diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c index

Rusty, ok, I think I've addressed your comments so far here. Coming next: - TSO - tap support Thanks! --- This implements vhost: a kernel-level backend for virtio, The main motivation for this work is to reduce virtualization overhead for virtio by removing system calls on data path, without guest changes. For virtio-net, this removes up to 4 system calls per packet: vm exit for kick,

Rusty, ok, I think I've addressed your comments so far here. Coming next: - TSO - tap support Thanks! --- This implements vhost: a kernel-level backend for virtio, The main motivation for this work is to reduce virtualization overhead for virtio by removing system calls on data path, without guest changes. For virtio-net, this removes up to 4 system calls per packet: vm exit for kick,

When mm switched to matches that of active mm, we don't need to increment and then drop the mm count. Making that conditional reduces contention on that cache line on SMP systems. Acked-by: Andrea Arcangeli <aarcange at redhat.com> Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- mm/mmu_context.c | 9 ++++++--- 1 files changed, 6 insertions(+), 3 deletions(-) diff

When mm switched to matches that of active mm, we don't need to increment and then drop the mm count. Making that conditional reduces contention on that cache line on SMP systems. Acked-by: Andrea Arcangeli <aarcange at redhat.com> Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- mm/mmu_context.c | 9 ++++++--- 1 files changed, 6 insertions(+), 3 deletions(-) diff

vhost net module wants to do copy to/from user from a kernel thread, which needs use_mm (like what fs/aio has). Move that into mm/ and export to modules. Acked-by: Andrew Morton <akpm at linux-foundation.org> Acked-by: Andrea Arcangeli <aarcange at redhat.com> Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- fs/aio.c | 47

vhost net module wants to do copy to/from user from a kernel thread, which needs use_mm (like what fs/aio has). Move that into mm/ and export to modules. Acked-by: Andrew Morton <akpm at linux-foundation.org> Acked-by: Andrea Arcangeli <aarcange at redhat.com> Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- fs/aio.c | 47

This enables actual support for MSI-X in virtio PCI. First user will be virtio-net. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- hw/virtio-pci.c | 152 ++++++++++++++++++++++++++++++++++++++++-------------- rules.mak | 2 +- 2 files changed, 113 insertions(+), 41 deletions(-) diff --git a/hw/virtio-pci.c b/hw/virtio-pci.c index d4a134d..d3f4884 100644 ---

This enables actual support for MSI-X in virtio PCI. First user will be virtio-net. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- hw/virtio-pci.c | 152 ++++++++++++++++++++++++++++++++++++++++-------------- rules.mak | 2 +- 2 files changed, 113 insertions(+), 41 deletions(-) diff --git a/hw/virtio-pci.c b/hw/virtio-pci.c index d4a134d..d3f4884 100644 ---

Extend virtio to support many interrupt vectors, and rearrange code in preparation for multi-vector support (mostly move reset out to bindings, because we will have to reset the vectors in transport-specific code). Actual bindings in pci, and use in net, to follow. Load and save are not connected to bindings yet, so they are left stubbed out for now. Signed-off-by: Michael S. Tsirkin <mst at

Extend virtio to support many interrupt vectors, and rearrange code in preparation for multi-vector support (mostly move reset out to bindings, because we will have to reset the vectors in transport-specific code). Actual bindings in pci, and use in net, to follow. Load and save are not connected to bindings yet, so they are left stubbed out for now. Signed-off-by: Michael S. Tsirkin <mst at

This implements optional MSI-X support in virtio_pci. MSI-X is used whenever the host supports at least 2 MSI-X vectors: 1 for configuration changes and 1 for virtqueues. Per-virtqueue vectors are allocated if enough vectors available. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/virtio/virtio_pci.c | 227 +++++++++++++++++++++++++++++++++++++++----

This implements optional MSI-X support in virtio_pci. MSI-X is used whenever the host supports at least 2 MSI-X vectors: 1 for configuration changes and 1 for virtqueues. Per-virtqueue vectors are allocated if enough vectors available. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/virtio/virtio_pci.c | 227 +++++++++++++++++++++++++++++++++++++++----

Add "cmask" table of constant register masks: if a bit is not writeable and is set in cmask table, this bit is checked on load. An attempt to load an image that would change such a register causes load to fail. Use this table to make sure that load does not modify registers that guest can not change (directly or indirectly). Note: we can't just assume that read-only registers never

Add "cmask" table of constant register masks: if a bit is not writeable and is set in cmask table, this bit is checked on load. An attempt to load an image that would change such a register causes load to fail. Use this table to make sure that load does not modify registers that guest can not change (directly or indirectly). Note: we can't just assume that read-only registers never