Initial commit (and hopefully the only one)

1 files changed, 104 insertions, 0 deletions

diff --git a/vfio-msi-5.patch b/vfio-msi-5.patch
new file mode 100644
index 000000000000..9033b604a7ca
--- /dev/null
+++ b/vfio-msi-5.patch
@@ -0,0 +1,104 @@
+With vfio ioeventfd support, we can program vfio-pci to perform a
+specified BAR write when an eventfd is triggered.  This allows the
+KVM ioeventfd to be wired directly to vfio-pci, entirely avoiding
+userspace handling for these events.  On the same micro-benchmark
+where the ioeventfd got us to almost 90% of performance versus
+disabling the GeForce quirks, this gets us to within 95%.
+
+Signed-off-by: Alex Williamson <address@hidden>
+---
+ hw/vfio/pci-quirks.c |   42 ++++++++++++++++++++++++++++++++++++------
+ 1 file changed, 36 insertions(+), 6 deletions(-)
+
+diff --git a/hw/vfio/pci-quirks.c b/hw/vfio/pci-quirks.c
+index e739efe601b1..35a4d5197e2d 100644
+--- a/hw/vfio/pci-quirks.c
++++ b/hw/vfio/pci-quirks.c
+@@ -16,6 +16,7 @@
+ #include "qemu/range.h"
+ #include "qapi/error.h"
+ #include "qapi/visitor.h"
++#include <sys/ioctl.h>
+ #include "hw/nvram/fw_cfg.h"
+ #include "pci.h"
+ #include "trace.h"
+@@ -287,13 +288,27 @@ static VFIOQuirk *vfio_quirk_alloc(int nr_mem)
+     return quirk;
+ }
+
+-static void vfio_ioeventfd_exit(VFIOIOEventFD *ioeventfd)
++static void vfio_ioeventfd_exit(VFIOPCIDevice *vdev, VFIOIOEventFD *ioeventfd)
+ {
++    struct vfio_device_ioeventfd vfio_ioeventfd;
++
+     QLIST_REMOVE(ioeventfd, next);
++
+     memory_region_del_eventfd(ioeventfd->mr, ioeventfd->addr, ioeventfd->size,
+                               ioeventfd->match_data, ioeventfd->data,
+                               &ioeventfd->e);
++
+     qemu_set_fd_handler(event_notifier_get_fd(&ioeventfd->e), NULL, NULL, NULL);
++
++    vfio_ioeventfd.argsz = sizeof(vfio_ioeventfd);
++    vfio_ioeventfd.flags = ioeventfd->size;
++    vfio_ioeventfd.data = ioeventfd->data;
++    vfio_ioeventfd.offset = ioeventfd->region->fd_offset +
++                            ioeventfd->region_addr;
++    vfio_ioeventfd.fd = -1;
++
++    ioctl(vdev->vbasedev.fd, VFIO_DEVICE_IOEVENTFD, &vfio_ioeventfd);
++
+     event_notifier_cleanup(&ioeventfd->e);
+     g_free(ioeventfd);
+ }
+@@ -315,6 +330,8 @@ static VFIOIOEventFD *vfio_ioeventfd_init(VFIOPCIDevice *vdev,
+                                           hwaddr region_addr)
+ {
+     VFIOIOEventFD *ioeventfd = g_malloc0(sizeof(*ioeventfd));
++    struct vfio_device_ioeventfd vfio_ioeventfd;
++    char vfio_enabled = '+';
+
+     if (event_notifier_init(&ioeventfd->e, 0)) {
+         g_free(ioeventfd);
+@@ -329,15 +346,28 @@ static VFIOIOEventFD *vfio_ioeventfd_init(VFIOPCIDevice *vdev,
+     ioeventfd->region = region;
+     ioeventfd->region_addr = region_addr;
+
+-    qemu_set_fd_handler(event_notifier_get_fd(&ioeventfd->e),
+-                        vfio_ioeventfd_handler, NULL, ioeventfd);
++    vfio_ioeventfd.argsz = sizeof(vfio_ioeventfd);
++    vfio_ioeventfd.flags = ioeventfd->size;
++    vfio_ioeventfd.data = ioeventfd->data;
++    vfio_ioeventfd.offset = ioeventfd->region->fd_offset +
++                            ioeventfd->region_addr;
++    vfio_ioeventfd.fd = event_notifier_get_fd(&ioeventfd->e);
++
++    if (ioctl(vdev->vbasedev.fd,
++              VFIO_DEVICE_IOEVENTFD, &vfio_ioeventfd) != 0) {
++        qemu_set_fd_handler(event_notifier_get_fd(&ioeventfd->e),
++                            vfio_ioeventfd_handler, NULL, ioeventfd);
++        vfio_enabled = '-';
++    }
++
+     memory_region_add_eventfd(ioeventfd->mr, ioeventfd->addr,
+                               ioeventfd->size, ioeventfd->match_data,
+                               ioeventfd->data, &ioeventfd->e);
+
+     info_report("Enabled automatic ioeventfd acceleration for %s region %d, "
+-                "offset 0x%"HWADDR_PRIx", data 0x%"PRIx64", size %u",
+-                vdev->vbasedev.name, region->nr, region_addr, data, size);
++                "offset 0x%"HWADDR_PRIx", data 0x%"PRIx64", size %u, vfio%c",
++                vdev->vbasedev.name, region->nr, region_addr, data, size,
++                vfio_enabled);
+
+     return ioeventfd;
+ }
+@@ -1767,7 +1797,7 @@ void vfio_bar_quirk_exit(VFIOPCIDevice *vdev, int nr)
+
+     QLIST_FOREACH(quirk, &bar->quirks, next) {
+         while (!QLIST_EMPTY(&quirk->ioeventfds)) {
+-            vfio_ioeventfd_exit(QLIST_FIRST(&quirk->ioeventfds));
++            vfio_ioeventfd_exit(vdev, QLIST_FIRST(&quirk->ioeventfds));
+         }
+
+         for (i = 0; i < quirk->nr_mem; i++) {