Message ID | 20220609143727.1151816-5-eesposit@redhat.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | virtio-blk: removal of AioContext lock | expand |
On Thu, Jun 09, 2022 at 10:37:23AM -0400, Emanuele Giuseppe Esposito wrote: > All the callbacks below are always running in the main loop. > > The callbacks are the following: > - start/stop_ioeventfd: these are the callbacks where > blk_set_aio_context(iothread) is done, so they are called in the main > loop. > > - save and load: called during migration, when VM is stopped from the > main loop. > > - reset: before calling this callback, stop_ioeventfd is invoked, so > it can only run in the main loop. > > - set_status: going through all the callers we can see it is called > from a MemoryRegionOps callback, which always run in the main loop. > > - realize: iothread is not even created yet. > > Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> > --- > hw/block/virtio-blk.c | 2 ++ > hw/virtio/virtio-bus.c | 5 +++++ > hw/virtio/virtio-pci.c | 2 ++ > hw/virtio/virtio.c | 8 ++++++++ > 4 files changed, 17 insertions(+) > > diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c > index 29a9c53ebc..4e6421c35e 100644 > --- a/hw/block/virtio-blk.c > +++ b/hw/block/virtio-blk.c > @@ -1032,6 +1032,8 @@ static void virtio_blk_set_status(VirtIODevice *vdev, uint8_t status) > { > VirtIOBlock *s = VIRTIO_BLK(vdev); > > + GLOBAL_STATE_CODE(); > + > if (!(status & (VIRTIO_CONFIG_S_DRIVER | VIRTIO_CONFIG_S_DRIVER_OK))) { > assert(!s->dataplane_started); > } > diff --git a/hw/virtio/virtio-bus.c b/hw/virtio/virtio-bus.c > index d7ec023adf..0891ddb2ff 100644 > --- a/hw/virtio/virtio-bus.c > +++ b/hw/virtio/virtio-bus.c > @@ -23,6 +23,7 @@ > */ > > #include "qemu/osdep.h" > +#include "qemu/main-loop.h" > #include "qemu/error-report.h" > #include "qemu/module.h" > #include "qapi/error.h" > @@ -223,6 +224,8 @@ int virtio_bus_start_ioeventfd(VirtioBusState *bus) > VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev); > int r; > > + GLOBAL_STATE_CODE(); > + > if (!k->ioeventfd_assign || !k->ioeventfd_enabled(proxy)) { > return -ENOSYS; > } > @@ -247,6 +250,8 @@ void virtio_bus_stop_ioeventfd(VirtioBusState *bus) > VirtIODevice *vdev; > VirtioDeviceClass *vdc; > > + GLOBAL_STATE_CODE(); > + > if (!bus->ioeventfd_started) { > return; > } > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c > index 0566ad7d00..6798039391 100644 > --- a/hw/virtio/virtio-pci.c > +++ b/hw/virtio/virtio-pci.c > @@ -301,6 +301,8 @@ static void virtio_ioport_write(void *opaque, uint32_t addr, uint32_t val) > VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus); > hwaddr pa; > > + GLOBAL_STATE_CODE(); > + > switch (addr) { > case VIRTIO_PCI_GUEST_FEATURES: > /* Guest does not negotiate properly? We have to assume nothing. */ > diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c > index 5d607aeaa0..2650504dd4 100644 > --- a/hw/virtio/virtio.c > +++ b/hw/virtio/virtio.c > @@ -1977,6 +1977,8 @@ int virtio_set_status(VirtIODevice *vdev, uint8_t val) > VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); > trace_virtio_set_status(vdev, val); > > + GLOBAL_STATE_CODE(); > + > if (virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) { > if (!(vdev->status & VIRTIO_CONFIG_S_FEATURES_OK) && > val & VIRTIO_CONFIG_S_FEATURES_OK) { > @@ -2025,6 +2027,8 @@ void virtio_reset(void *opaque) > VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); > int i; > > + GLOBAL_STATE_CODE(); > + > virtio_set_status(vdev, 0); > if (current_cpu) { > /* Guest initiated reset */ > @@ -2882,6 +2886,8 @@ int virtio_save(VirtIODevice *vdev, QEMUFile *f) > uint32_t guest_features_lo = (vdev->guest_features & 0xffffffff); > int i; > > + GLOBAL_STATE_CODE(); > + > if (k->save_config) { > k->save_config(qbus->parent, f); > } > @@ -3024,6 +3030,8 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id) > VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); > VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev); > > + GLOBAL_STATE_CODE(); > + > /* > * We poison the endianness to ensure it does not get used before > * subsections have been loaded. > -- > 2.31.1
On Thu, Jun 09, 2022 at 10:37:23AM -0400, Emanuele Giuseppe Esposito wrote: > All the callbacks below are always running in the main loop. > > The callbacks are the following: > - start/stop_ioeventfd: these are the callbacks where > blk_set_aio_context(iothread) is done, so they are called in the main > loop. > > - save and load: called during migration, when VM is stopped from the > main loop. > > - reset: before calling this callback, stop_ioeventfd is invoked, so > it can only run in the main loop. > > - set_status: going through all the callers we can see it is called > from a MemoryRegionOps callback, which always run in the main loop. > > - realize: iothread is not even created yet. > > Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> > --- > hw/block/virtio-blk.c | 2 ++ > hw/virtio/virtio-bus.c | 5 +++++ > hw/virtio/virtio-pci.c | 2 ++ > hw/virtio/virtio.c | 8 ++++++++ > 4 files changed, 17 insertions(+) Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c index 29a9c53ebc..4e6421c35e 100644 --- a/hw/block/virtio-blk.c +++ b/hw/block/virtio-blk.c @@ -1032,6 +1032,8 @@ static void virtio_blk_set_status(VirtIODevice *vdev, uint8_t status) { VirtIOBlock *s = VIRTIO_BLK(vdev); + GLOBAL_STATE_CODE(); + if (!(status & (VIRTIO_CONFIG_S_DRIVER | VIRTIO_CONFIG_S_DRIVER_OK))) { assert(!s->dataplane_started); } diff --git a/hw/virtio/virtio-bus.c b/hw/virtio/virtio-bus.c index d7ec023adf..0891ddb2ff 100644 --- a/hw/virtio/virtio-bus.c +++ b/hw/virtio/virtio-bus.c @@ -23,6 +23,7 @@ */ #include "qemu/osdep.h" +#include "qemu/main-loop.h" #include "qemu/error-report.h" #include "qemu/module.h" #include "qapi/error.h" @@ -223,6 +224,8 @@ int virtio_bus_start_ioeventfd(VirtioBusState *bus) VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev); int r; + GLOBAL_STATE_CODE(); + if (!k->ioeventfd_assign || !k->ioeventfd_enabled(proxy)) { return -ENOSYS; } @@ -247,6 +250,8 @@ void virtio_bus_stop_ioeventfd(VirtioBusState *bus) VirtIODevice *vdev; VirtioDeviceClass *vdc; + GLOBAL_STATE_CODE(); + if (!bus->ioeventfd_started) { return; } diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c index 0566ad7d00..6798039391 100644 --- a/hw/virtio/virtio-pci.c +++ b/hw/virtio/virtio-pci.c @@ -301,6 +301,8 @@ static void virtio_ioport_write(void *opaque, uint32_t addr, uint32_t val) VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus); hwaddr pa; + GLOBAL_STATE_CODE(); + switch (addr) { case VIRTIO_PCI_GUEST_FEATURES: /* Guest does not negotiate properly? We have to assume nothing. */ diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 5d607aeaa0..2650504dd4 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -1977,6 +1977,8 @@ int virtio_set_status(VirtIODevice *vdev, uint8_t val) VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); trace_virtio_set_status(vdev, val); + GLOBAL_STATE_CODE(); + if (virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) { if (!(vdev->status & VIRTIO_CONFIG_S_FEATURES_OK) && val & VIRTIO_CONFIG_S_FEATURES_OK) { @@ -2025,6 +2027,8 @@ void virtio_reset(void *opaque) VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); int i; + GLOBAL_STATE_CODE(); + virtio_set_status(vdev, 0); if (current_cpu) { /* Guest initiated reset */ @@ -2882,6 +2886,8 @@ int virtio_save(VirtIODevice *vdev, QEMUFile *f) uint32_t guest_features_lo = (vdev->guest_features & 0xffffffff); int i; + GLOBAL_STATE_CODE(); + if (k->save_config) { k->save_config(qbus->parent, f); } @@ -3024,6 +3030,8 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id) VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev); + GLOBAL_STATE_CODE(); + /* * We poison the endianness to ensure it does not get used before * subsections have been loaded.
All the callbacks below are always running in the main loop. The callbacks are the following: - start/stop_ioeventfd: these are the callbacks where blk_set_aio_context(iothread) is done, so they are called in the main loop. - save and load: called during migration, when VM is stopped from the main loop. - reset: before calling this callback, stop_ioeventfd is invoked, so it can only run in the main loop. - set_status: going through all the callers we can see it is called from a MemoryRegionOps callback, which always run in the main loop. - realize: iothread is not even created yet. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> --- hw/block/virtio-blk.c | 2 ++ hw/virtio/virtio-bus.c | 5 +++++ hw/virtio/virtio-pci.c | 2 ++ hw/virtio/virtio.c | 8 ++++++++ 4 files changed, 17 insertions(+)