* [Qemu-devel] [PATCH v3 1/7] virtio-scsi-dataplane: Code to run virtio-scsi on iothread
2014-09-23 7:49 [Qemu-devel] [PATCH v3 0/7] virtio-scsi: Dataplane on single iothread Fam Zheng
@ 2014-09-23 7:49 ` Fam Zheng
2014-09-23 7:49 ` [Qemu-devel] [PATCH v3 2/7] virtio-scsi: Hook up with dataplane Fam Zheng
` (6 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: Fam Zheng @ 2014-09-23 7:49 UTC (permalink / raw)
To: qemu-devel; +Cc: kwolf, pbonzini, stefanha
This implements the core part of dataplane feature of virtio-scsi.
A few fields are added in VirtIOSCSICommon to maintain the dataplane
status. These fields are managed by a new source file:
virtio-scsi-dataplane.c.
Most code in this file will run on an iothread, unless otherwise
commented as in a global mutex context, such as those functions to
start, stop and setting the iothread property.
Upon start, we set up guest/host event notifiers, in a same way as
virtio-blk does. The handlers then pop request from vring and call into
virtio-scsi.c functions to process it. So we need to make sure make all
those called functions work with iothread, too.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
hw/scsi/Makefile.objs | 2 +-
hw/scsi/virtio-scsi-dataplane.c | 222 ++++++++++++++++++++++++++++++++++++++++
include/hw/virtio/virtio-scsi.h | 25 ++++-
3 files changed, 245 insertions(+), 4 deletions(-)
create mode 100644 hw/scsi/virtio-scsi-dataplane.c
diff --git a/hw/scsi/Makefile.objs b/hw/scsi/Makefile.objs
index 121ddc5..40c79d3 100644
--- a/hw/scsi/Makefile.objs
+++ b/hw/scsi/Makefile.objs
@@ -8,6 +8,6 @@ common-obj-$(CONFIG_ESP_PCI) += esp-pci.o
obj-$(CONFIG_PSERIES) += spapr_vscsi.o
ifeq ($(CONFIG_VIRTIO),y)
-obj-y += virtio-scsi.o
+obj-y += virtio-scsi.o virtio-scsi-dataplane.o
obj-$(CONFIG_VHOST_SCSI) += vhost-scsi.o
endif
diff --git a/hw/scsi/virtio-scsi-dataplane.c b/hw/scsi/virtio-scsi-dataplane.c
new file mode 100644
index 0000000..acbf622
--- /dev/null
+++ b/hw/scsi/virtio-scsi-dataplane.c
@@ -0,0 +1,222 @@
+/*
+ * Virtio SCSI dataplane
+ *
+ * Copyright Red Hat, Inc. 2014
+ *
+ * Authors:
+ * Fam Zheng <famz@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#include "hw/virtio/virtio-scsi.h"
+#include "qemu/error-report.h"
+#include <hw/scsi/scsi.h>
+#include <block/scsi.h>
+#include <hw/virtio/virtio-bus.h>
+#include "hw/virtio/virtio-access.h"
+#include "stdio.h"
+
+/* Context: QEMU global mutex held */
+void virtio_scsi_set_iothread(VirtIOSCSI *s, IOThread *iothread)
+{
+ BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(s)));
+ VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
+ VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s);
+
+ assert(!s->ctx);
+ s->ctx = iothread_get_aio_context(vs->conf.iothread);
+
+ /* Don't try if transport does not support notifiers. */
+ if (!k->set_guest_notifiers || !k->set_host_notifier) {
+ fprintf(stderr, "virtio-scsi: Failed to set iothread "
+ "(transport does not support notifiers)");
+ exit(1);
+ }
+}
+
+static VirtIOSCSIVring *virtio_scsi_vring_init(VirtIOSCSI *s,
+ VirtQueue *vq,
+ EventNotifierHandler *handler,
+ int n)
+{
+ BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(s)));
+ VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
+ VirtIOSCSIVring *r = g_slice_new(VirtIOSCSIVring);
+
+ /* Set up virtqueue notify */
+ if (k->set_host_notifier(qbus->parent, n, true) != 0) {
+ fprintf(stderr, "virtio-scsi: Failed to set host notifier\n");
+ exit(1);
+ }
+ r->host_notifier = *virtio_queue_get_host_notifier(vq);
+ r->guest_notifier = *virtio_queue_get_guest_notifier(vq);
+ aio_set_event_notifier(s->ctx, &r->host_notifier, handler);
+
+ r->parent = s;
+
+ if (!vring_setup(&r->vring, VIRTIO_DEVICE(s), n)) {
+ fprintf(stderr, "virtio-scsi: VRing setup failed\n");
+ exit(1);
+ }
+ return r;
+}
+
+VirtIOSCSIReq *virtio_scsi_pop_req_vring(VirtIOSCSI *s,
+ VirtIOSCSIVring *vring)
+{
+ VirtIOSCSIReq *req = virtio_scsi_init_req(s, NULL);
+ int r;
+
+ req->vring = vring;
+ r = vring_pop((VirtIODevice *)s, &vring->vring, &req->elem);
+ if (r < 0) {
+ virtio_scsi_free_req(req);
+ req = NULL;
+ }
+ return req;
+}
+
+void virtio_scsi_vring_push_notify(VirtIOSCSIReq *req)
+{
+ vring_push(&req->vring->vring, &req->elem,
+ req->qsgl.size + req->resp_iov.size);
+ event_notifier_set(&req->vring->guest_notifier);
+}
+
+static void virtio_scsi_iothread_handle_ctrl(EventNotifier *notifier)
+{
+ VirtIOSCSIVring *vring = container_of(notifier,
+ VirtIOSCSIVring, host_notifier);
+ VirtIOSCSI *s = VIRTIO_SCSI(vring->parent);
+ VirtIOSCSIReq *req;
+
+ event_notifier_test_and_clear(notifier);
+ while ((req = virtio_scsi_pop_req_vring(s, vring))) {
+ virtio_scsi_handle_ctrl_req(s, req);
+ }
+}
+
+static void virtio_scsi_iothread_handle_event(EventNotifier *notifier)
+{
+ VirtIOSCSIVring *vring = container_of(notifier,
+ VirtIOSCSIVring, host_notifier);
+ VirtIOSCSI *s = vring->parent;
+ VirtIODevice *vdev = VIRTIO_DEVICE(s);
+
+ event_notifier_test_and_clear(notifier);
+
+ if (!(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) {
+ return;
+ }
+
+ if (s->events_dropped) {
+ virtio_scsi_push_event(s, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
+ }
+}
+
+static void virtio_scsi_iothread_handle_cmd(EventNotifier *notifier)
+{
+ VirtIOSCSIVring *vring = container_of(notifier,
+ VirtIOSCSIVring, host_notifier);
+ VirtIOSCSI *s = (VirtIOSCSI *)vring->parent;
+ VirtIOSCSIReq *req;
+
+ event_notifier_test_and_clear(notifier);
+ while ((req = virtio_scsi_pop_req_vring(s, vring))) {
+ virtio_scsi_handle_cmd_req(s, req);
+ }
+}
+
+/* Context: QEMU global mutex held */
+void virtio_scsi_dataplane_start(VirtIOSCSI *s)
+{
+ int i;
+ int rc;
+ BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(s)));
+ VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
+ VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s);
+
+ if (s->dataplane_started ||
+ s->dataplane_starting ||
+ s->ctx != iothread_get_aio_context(vs->conf.iothread)) {
+ return;
+ }
+
+ s->dataplane_starting = true;
+
+ /* Set up guest notifier (irq) */
+ rc = k->set_guest_notifiers(qbus->parent, vs->conf.num_queues + 2, true);
+ if (rc != 0) {
+ fprintf(stderr, "virtio-scsi: Failed to set guest notifiers, "
+ "ensure -enable-kvm is set\n");
+ exit(1);
+ }
+
+ aio_context_acquire(s->ctx);
+ s->ctrl_vring = virtio_scsi_vring_init(s, vs->ctrl_vq,
+ virtio_scsi_iothread_handle_ctrl,
+ 0);
+ s->event_vring = virtio_scsi_vring_init(s, vs->event_vq,
+ virtio_scsi_iothread_handle_event,
+ 1);
+ s->cmd_vrings = g_malloc0(sizeof(VirtIOSCSIVring) * vs->conf.num_queues);
+ for (i = 0; i < vs->conf.num_queues; i++) {
+ s->cmd_vrings[i] =
+ virtio_scsi_vring_init(s, vs->cmd_vqs[i],
+ virtio_scsi_iothread_handle_cmd,
+ i + 2);
+ }
+
+ aio_context_release(s->ctx);
+ s->dataplane_starting = false;
+ s->dataplane_started = true;
+}
+
+/* Context: QEMU global mutex held */
+void virtio_scsi_dataplane_stop(VirtIOSCSI *s)
+{
+ BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(s)));
+ VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
+ VirtIODevice *vdev = VIRTIO_DEVICE(s);
+ VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s);
+ int i;
+
+ if (!s->dataplane_started || s->dataplane_stopping) {
+ return;
+ }
+ s->dataplane_stopping = true;
+ assert(s->ctx == iothread_get_aio_context(vs->conf.iothread));
+
+ aio_context_acquire(s->ctx);
+
+ aio_set_event_notifier(s->ctx, &s->ctrl_vring->host_notifier, NULL);
+ aio_set_event_notifier(s->ctx, &s->event_vring->host_notifier, NULL);
+ for (i = 0; i < vs->conf.num_queues; i++) {
+ aio_set_event_notifier(s->ctx, &s->cmd_vrings[i]->host_notifier, NULL);
+ }
+
+ bdrv_drain_all(); /* ensure there are no in-flight requests */
+
+ aio_context_release(s->ctx);
+
+ /* Sync vring state back to virtqueue so that non-dataplane request
+ * processing can continue when we disable the host notifier below.
+ */
+ vring_teardown(&s->ctrl_vring->vring, vdev, 0);
+ vring_teardown(&s->event_vring->vring, vdev, 1);
+ for (i = 0; i < vs->conf.num_queues; i++) {
+ vring_teardown(&s->cmd_vrings[i]->vring, vdev, 2 + i);
+ }
+
+ for (i = 0; i < vs->conf.num_queues + 2; i++) {
+ k->set_host_notifier(qbus->parent, i, false);
+ }
+
+ /* Clean up guest notifier (irq) */
+ k->set_guest_notifiers(qbus->parent, vs->conf.num_queues + 2, false);
+ s->dataplane_stopping = false;
+ s->dataplane_started = false;
+}
diff --git a/include/hw/virtio/virtio-scsi.h b/include/hw/virtio/virtio-scsi.h
index 1ed93ab..8e1968f 100644
--- a/include/hw/virtio/virtio-scsi.h
+++ b/include/hw/virtio/virtio-scsi.h
@@ -156,10 +156,10 @@ struct VirtIOSCSIConf {
IOThread *iothread;
};
-struct VirtIOSCSICommon;
+struct VirtIOSCSI;
typedef struct {
- struct VirtIOSCSICommon *parent;
+ struct VirtIOSCSI *parent;
Vring vring;
EventNotifier host_notifier;
EventNotifier guest_notifier;
@@ -176,12 +176,24 @@ typedef struct VirtIOSCSICommon {
VirtQueue **cmd_vqs;
} VirtIOSCSICommon;
-typedef struct {
+typedef struct VirtIOSCSI {
VirtIOSCSICommon parent_obj;
SCSIBus bus;
int resetting;
bool events_dropped;
+
+ /* Fields for dataplane below */
+ AioContext *ctx; /* one iothread per virtio-scsi-pci for now */
+
+ /* Vring is used instead of vq in dataplane code, because of the underlying
+ * memory layer thread safety */
+ VirtIOSCSIVring *ctrl_vring;
+ VirtIOSCSIVring *event_vring;
+ VirtIOSCSIVring **cmd_vrings;
+ bool dataplane_started;
+ bool dataplane_starting;
+ bool dataplane_stopping;
} VirtIOSCSI;
typedef struct VirtIOSCSIReq {
@@ -248,4 +260,11 @@ void virtio_scsi_free_req(VirtIOSCSIReq *req);
void virtio_scsi_push_event(VirtIOSCSI *s, SCSIDevice *dev,
uint32_t event, uint32_t reason);
+void virtio_scsi_set_iothread(VirtIOSCSI *s, IOThread *iothread);
+void virtio_scsi_dataplane_start(VirtIOSCSI *s);
+void virtio_scsi_dataplane_stop(VirtIOSCSI *s);
+void virtio_scsi_vring_push_notify(VirtIOSCSIReq *req);
+VirtIOSCSIReq *virtio_scsi_pop_req_vring(VirtIOSCSI *s,
+ VirtIOSCSIVring *vring);
+
#endif /* _QEMU_VIRTIO_SCSI_H */
--
1.9.3
^ permalink raw reply related [flat|nested] 9+ messages in thread* [Qemu-devel] [PATCH v3 2/7] virtio-scsi: Hook up with dataplane
2014-09-23 7:49 [Qemu-devel] [PATCH v3 0/7] virtio-scsi: Dataplane on single iothread Fam Zheng
2014-09-23 7:49 ` [Qemu-devel] [PATCH v3 1/7] virtio-scsi-dataplane: Code to run virtio-scsi on iothread Fam Zheng
@ 2014-09-23 7:49 ` Fam Zheng
2014-09-23 7:49 ` [Qemu-devel] [PATCH v3 3/7] virtio-scsi: Add migration state notifier for dataplane code Fam Zheng
` (5 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: Fam Zheng @ 2014-09-23 7:49 UTC (permalink / raw)
To: qemu-devel; +Cc: kwolf, pbonzini, stefanha
This enables the virtio-scsi-dataplane code by setting the iothread
in virtio-scsi device, and makes any function that is called by
back from dataplane to cooperate with the caller: they need to be
vring/iothread aware when handling the requests and using scsi devices
on the bus.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
hw/scsi/virtio-scsi.c | 52 +++++++++++++++++++++++++++++++++++++++++++++++----
1 file changed, 48 insertions(+), 4 deletions(-)
diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c
index 91ead26..dc705f0 100644
--- a/hw/scsi/virtio-scsi.c
+++ b/hw/scsi/virtio-scsi.c
@@ -69,13 +69,19 @@ static void virtio_scsi_complete_req(VirtIOSCSIReq *req)
VirtIODevice *vdev = VIRTIO_DEVICE(s);
qemu_iovec_from_buf(&req->resp_iov, 0, &req->resp, req->resp_size);
- virtqueue_push(vq, &req->elem, req->qsgl.size + req->resp_iov.size);
+ if (req->vring) {
+ assert(req->vq == NULL);
+ virtio_scsi_vring_push_notify(req);
+ } else {
+ virtqueue_push(vq, &req->elem, req->qsgl.size + req->resp_iov.size);
+ virtio_notify(vdev, vq);
+ }
+
if (req->sreq) {
req->sreq->hba_private = NULL;
scsi_req_unref(req->sreq);
}
virtio_scsi_free_req(req);
- virtio_notify(vdev, vq);
}
static void virtio_scsi_bad_req(void)
@@ -208,6 +214,11 @@ static void virtio_scsi_do_tmf(VirtIOSCSI *s, VirtIOSCSIReq *req)
BusChild *kid;
int target;
+ if (s->dataplane_started && bdrv_get_aio_context(d->conf.bs) != s->ctx) {
+ aio_context_acquire(s->ctx);
+ bdrv_set_aio_context(d->conf.bs, s->ctx);
+ aio_context_release(s->ctx);
+ }
/* Here VIRTIO_SCSI_S_OK means "FUNCTION COMPLETE". */
req->resp.tmf.response = VIRTIO_SCSI_S_OK;
@@ -346,6 +357,10 @@ static void virtio_scsi_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
VirtIOSCSI *s = (VirtIOSCSI *)vdev;
VirtIOSCSIReq *req;
+ if (s->ctx) {
+ virtio_scsi_dataplane_start(s);
+ return;
+ }
while ((req = virtio_scsi_pop_req(s, vq))) {
virtio_scsi_handle_ctrl_req(s, req);
}
@@ -457,6 +472,11 @@ void virtio_scsi_handle_cmd_req(VirtIOSCSI *s, VirtIOSCSIReq *req)
virtio_scsi_complete_cmd_req(req);
return;
}
+ if (s->dataplane_started && bdrv_get_aio_context(d->conf.bs) != s->ctx) {
+ aio_context_acquire(s->ctx);
+ bdrv_set_aio_context(d->conf.bs, s->ctx);
+ aio_context_release(s->ctx);
+ }
req->sreq = scsi_req_new(d, req->req.cmd.tag,
virtio_scsi_get_lun(req->req.cmd.lun),
req->req.cdb, req);
@@ -481,6 +501,10 @@ static void virtio_scsi_handle_cmd(VirtIODevice *vdev, VirtQueue *vq)
VirtIOSCSI *s = (VirtIOSCSI *)vdev;
VirtIOSCSIReq *req;
+ if (s->ctx) {
+ virtio_scsi_dataplane_start(s);
+ return;
+ }
while ((req = virtio_scsi_pop_req(s, vq))) {
virtio_scsi_handle_cmd_req(s, req);
}
@@ -531,6 +555,9 @@ static void virtio_scsi_reset(VirtIODevice *vdev)
VirtIOSCSI *s = VIRTIO_SCSI(vdev);
VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(vdev);
+ if (s->ctx) {
+ virtio_scsi_dataplane_stop(s);
+ }
s->resetting++;
qbus_reset_all(&s->bus.qbus);
s->resetting--;
@@ -573,10 +600,19 @@ void virtio_scsi_push_event(VirtIOSCSI *s, SCSIDevice *dev,
return;
}
- req = virtio_scsi_pop_req(s, vs->event_vq);
+ if (s->dataplane_started) {
+ assert(s->ctx);
+ aio_context_acquire(s->ctx);
+ }
+
+ if (s->dataplane_started) {
+ req = virtio_scsi_pop_req_vring(s, s->event_vring);
+ } else {
+ req = virtio_scsi_pop_req(s, vs->event_vq);
+ }
if (!req) {
s->events_dropped = true;
- return;
+ goto out;
}
if (s->events_dropped) {
@@ -605,12 +641,20 @@ void virtio_scsi_push_event(VirtIOSCSI *s, SCSIDevice *dev,
evt->lun[3] = dev->lun & 0xFF;
}
virtio_scsi_complete_req(req);
+out:
+ if (s->dataplane_started) {
+ aio_context_release(s->ctx);
+ }
}
static void virtio_scsi_handle_event(VirtIODevice *vdev, VirtQueue *vq)
{
VirtIOSCSI *s = VIRTIO_SCSI(vdev);
+ if (s->ctx) {
+ virtio_scsi_dataplane_start(s);
+ return;
+ }
if (s->events_dropped) {
virtio_scsi_push_event(s, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
}
--
1.9.3
^ permalink raw reply related [flat|nested] 9+ messages in thread* [Qemu-devel] [PATCH v3 3/7] virtio-scsi: Add migration state notifier for dataplane code
2014-09-23 7:49 [Qemu-devel] [PATCH v3 0/7] virtio-scsi: Dataplane on single iothread Fam Zheng
2014-09-23 7:49 ` [Qemu-devel] [PATCH v3 1/7] virtio-scsi-dataplane: Code to run virtio-scsi on iothread Fam Zheng
2014-09-23 7:49 ` [Qemu-devel] [PATCH v3 2/7] virtio-scsi: Hook up with dataplane Fam Zheng
@ 2014-09-23 7:49 ` Fam Zheng
2014-09-23 7:49 ` [Qemu-devel] [PATCH v3 4/7] virtio-scsi: Two stages processing of cmd request Fam Zheng
` (4 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: Fam Zheng @ 2014-09-23 7:49 UTC (permalink / raw)
To: qemu-devel; +Cc: kwolf, pbonzini, stefanha
Similar to virtio-blk-dataplane, we stop the iothread while migration
starts and restart it when migration finishes.
Signed-off-by: Fam Zheng <famz@redhat.com>
---
hw/scsi/virtio-scsi.c | 35 ++++++++++++++++++++++++++++++++---
include/hw/virtio/virtio-scsi.h | 2 ++
2 files changed, 34 insertions(+), 3 deletions(-)
diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c
index dc705f0..57efe65 100644
--- a/hw/scsi/virtio-scsi.c
+++ b/hw/scsi/virtio-scsi.c
@@ -20,6 +20,7 @@
#include <block/scsi.h>
#include <hw/virtio/virtio-bus.h>
#include "hw/virtio/virtio-access.h"
+#include "migration/migration.h"
static inline int virtio_scsi_get_lun(uint8_t *lun)
{
@@ -357,7 +358,7 @@ static void virtio_scsi_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
VirtIOSCSI *s = (VirtIOSCSI *)vdev;
VirtIOSCSIReq *req;
- if (s->ctx) {
+ if (s->ctx && !s->dataplane_disabled) {
virtio_scsi_dataplane_start(s);
return;
}
@@ -501,7 +502,7 @@ static void virtio_scsi_handle_cmd(VirtIODevice *vdev, VirtQueue *vq)
VirtIOSCSI *s = (VirtIOSCSI *)vdev;
VirtIOSCSIReq *req;
- if (s->ctx) {
+ if (s->ctx && !s->dataplane_disabled) {
virtio_scsi_dataplane_start(s);
return;
}
@@ -651,7 +652,7 @@ static void virtio_scsi_handle_event(VirtIODevice *vdev, VirtQueue *vq)
{
VirtIOSCSI *s = VIRTIO_SCSI(vdev);
- if (s->ctx) {
+ if (s->ctx && !s->dataplane_disabled) {
virtio_scsi_dataplane_start(s);
return;
}
@@ -742,6 +743,31 @@ void virtio_scsi_common_realize(DeviceState *dev, Error **errp,
}
}
+/* Disable dataplane thread during live migration since it does not
+ * update the dirty memory bitmap yet.
+ */
+static void virtio_scsi_migration_state_changed(Notifier *notifier, void *data)
+{
+ VirtIOSCSI *s = container_of(notifier, VirtIOSCSI,
+ migration_state_notifier);
+ MigrationState *mig = data;
+
+ if (migration_in_setup(mig)) {
+ if (!s->dataplane_started) {
+ return;
+ }
+ virtio_scsi_dataplane_stop(s);
+ s->dataplane_disabled = true;
+ } else if (migration_has_finished(mig) ||
+ migration_has_failed(mig)) {
+ if (s->dataplane_started) {
+ return;
+ }
+ bdrv_drain_all(); /* complete in-flight non-dataplane requests */
+ s->dataplane_disabled = false;
+ }
+}
+
static void virtio_scsi_device_realize(DeviceState *dev, Error **errp)
{
VirtIODevice *vdev = VIRTIO_DEVICE(dev);
@@ -770,6 +796,8 @@ static void virtio_scsi_device_realize(DeviceState *dev, Error **errp)
register_savevm(dev, "virtio-scsi", virtio_scsi_id++, 1,
virtio_scsi_save, virtio_scsi_load, s);
+ s->migration_state_notifier.notify = virtio_scsi_migration_state_changed;
+ add_migration_state_change_notifier(&s->migration_state_notifier);
}
static void virtio_scsi_instance_init(Object *obj)
@@ -796,6 +824,7 @@ static void virtio_scsi_device_unrealize(DeviceState *dev, Error **errp)
VirtIOSCSI *s = VIRTIO_SCSI(dev);
unregister_savevm(dev, "virtio-scsi", s);
+ remove_migration_state_change_notifier(&s->migration_state_notifier);
virtio_scsi_common_unrealize(dev, errp);
}
diff --git a/include/hw/virtio/virtio-scsi.h b/include/hw/virtio/virtio-scsi.h
index 8e1968f..1a6a919 100644
--- a/include/hw/virtio/virtio-scsi.h
+++ b/include/hw/virtio/virtio-scsi.h
@@ -194,6 +194,8 @@ typedef struct VirtIOSCSI {
bool dataplane_started;
bool dataplane_starting;
bool dataplane_stopping;
+ bool dataplane_disabled;
+ Notifier migration_state_notifier;
} VirtIOSCSI;
typedef struct VirtIOSCSIReq {
--
1.9.3
^ permalink raw reply related [flat|nested] 9+ messages in thread* [Qemu-devel] [PATCH v3 4/7] virtio-scsi: Two stages processing of cmd request
2014-09-23 7:49 [Qemu-devel] [PATCH v3 0/7] virtio-scsi: Dataplane on single iothread Fam Zheng
` (2 preceding siblings ...)
2014-09-23 7:49 ` [Qemu-devel] [PATCH v3 3/7] virtio-scsi: Add migration state notifier for dataplane code Fam Zheng
@ 2014-09-23 7:49 ` Fam Zheng
2014-09-23 7:49 ` [Qemu-devel] [PATCH v3 5/7] virtio-scsi: Batched prepare for cmd reqs Fam Zheng
` (3 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: Fam Zheng @ 2014-09-23 7:49 UTC (permalink / raw)
To: qemu-devel; +Cc: kwolf, pbonzini, stefanha
Mechanical change, in preparation for bdrv_io_plug/bdrv_io_unplug.
Signed-off-by: Fam Zheng <famz@redhat.com>
---
hw/scsi/virtio-scsi-dataplane.c | 4 +++-
hw/scsi/virtio-scsi.c | 20 ++++++++++++--------
include/hw/virtio/virtio-scsi.h | 3 ++-
3 files changed, 17 insertions(+), 10 deletions(-)
diff --git a/hw/scsi/virtio-scsi-dataplane.c b/hw/scsi/virtio-scsi-dataplane.c
index acbf622..11f5705 100644
--- a/hw/scsi/virtio-scsi-dataplane.c
+++ b/hw/scsi/virtio-scsi-dataplane.c
@@ -126,7 +126,9 @@ static void virtio_scsi_iothread_handle_cmd(EventNotifier *notifier)
event_notifier_test_and_clear(notifier);
while ((req = virtio_scsi_pop_req_vring(s, vring))) {
- virtio_scsi_handle_cmd_req(s, req);
+ if (virtio_scsi_handle_cmd_req_prepare(s, req)) {
+ virtio_scsi_handle_cmd_req_submit(s, req);
+ }
}
}
diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c
index 57efe65..6cf070f 100644
--- a/hw/scsi/virtio-scsi.c
+++ b/hw/scsi/virtio-scsi.c
@@ -449,10 +449,9 @@ static void virtio_scsi_fail_cmd_req(VirtIOSCSIReq *req)
virtio_scsi_complete_cmd_req(req);
}
-void virtio_scsi_handle_cmd_req(VirtIOSCSI *s, VirtIOSCSIReq *req)
+bool virtio_scsi_handle_cmd_req_prepare(VirtIOSCSI *s, VirtIOSCSIReq *req)
{
VirtIOSCSICommon *vs = &s->parent_obj;
- int n;
SCSIDevice *d;
int rc;
@@ -464,14 +463,14 @@ void virtio_scsi_handle_cmd_req(VirtIOSCSI *s, VirtIOSCSIReq *req)
} else {
virtio_scsi_bad_req();
}
- return;
+ return false;
}
d = virtio_scsi_device_find(s, req->req.cmd.lun);
if (!d) {
req->resp.cmd.response = VIRTIO_SCSI_S_BAD_TARGET;
virtio_scsi_complete_cmd_req(req);
- return;
+ return false;
}
if (s->dataplane_started && bdrv_get_aio_context(d->conf.bs) != s->ctx) {
aio_context_acquire(s->ctx);
@@ -487,11 +486,14 @@ void virtio_scsi_handle_cmd_req(VirtIOSCSI *s, VirtIOSCSIReq *req)
req->sreq->cmd.xfer > req->qsgl.size)) {
req->resp.cmd.response = VIRTIO_SCSI_S_OVERRUN;
virtio_scsi_complete_cmd_req(req);
- return;
+ return false;
}
+ return true;
+}
- n = scsi_req_enqueue(req->sreq);
- if (n) {
+void virtio_scsi_handle_cmd_req_submit(VirtIOSCSI *s, VirtIOSCSIReq *req)
+{
+ if (scsi_req_enqueue(req->sreq)) {
scsi_req_continue(req->sreq);
}
}
@@ -507,7 +509,9 @@ static void virtio_scsi_handle_cmd(VirtIODevice *vdev, VirtQueue *vq)
return;
}
while ((req = virtio_scsi_pop_req(s, vq))) {
- virtio_scsi_handle_cmd_req(s, req);
+ if (virtio_scsi_handle_cmd_req_prepare(s, req)) {
+ virtio_scsi_handle_cmd_req_submit(s, req);
+ }
}
}
diff --git a/include/hw/virtio/virtio-scsi.h b/include/hw/virtio/virtio-scsi.h
index 1a6a919..1cc759a 100644
--- a/include/hw/virtio/virtio-scsi.h
+++ b/include/hw/virtio/virtio-scsi.h
@@ -256,7 +256,8 @@ void virtio_scsi_common_realize(DeviceState *dev, Error **errp,
void virtio_scsi_common_unrealize(DeviceState *dev, Error **errp);
void virtio_scsi_handle_ctrl_req(VirtIOSCSI *s, VirtIOSCSIReq *req);
-void virtio_scsi_handle_cmd_req(VirtIOSCSI *s, VirtIOSCSIReq *req);
+bool virtio_scsi_handle_cmd_req_prepare(VirtIOSCSI *s, VirtIOSCSIReq *req);
+void virtio_scsi_handle_cmd_req_submit(VirtIOSCSI *s, VirtIOSCSIReq *req);
VirtIOSCSIReq *virtio_scsi_init_req(VirtIOSCSI *s, VirtQueue *vq);
void virtio_scsi_free_req(VirtIOSCSIReq *req);
void virtio_scsi_push_event(VirtIOSCSI *s, SCSIDevice *dev,
--
1.9.3
^ permalink raw reply related [flat|nested] 9+ messages in thread* [Qemu-devel] [PATCH v3 5/7] virtio-scsi: Batched prepare for cmd reqs
2014-09-23 7:49 [Qemu-devel] [PATCH v3 0/7] virtio-scsi: Dataplane on single iothread Fam Zheng
` (3 preceding siblings ...)
2014-09-23 7:49 ` [Qemu-devel] [PATCH v3 4/7] virtio-scsi: Two stages processing of cmd request Fam Zheng
@ 2014-09-23 7:49 ` Fam Zheng
2014-09-23 7:49 ` [Qemu-devel] [PATCH v3 6/7] virtio-scsi: Call bdrv_io_plug/bdrv_io_unplug in cmd request handling Fam Zheng
` (2 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: Fam Zheng @ 2014-09-23 7:49 UTC (permalink / raw)
To: qemu-devel; +Cc: kwolf, pbonzini, stefanha
Queue the popped requests while calling
virtio_scsi_handle_cmd_req_prepare(), then submit them after all
prepared.
Signed-off-by: Fam Zheng <famz@redhat.com>
---
hw/scsi/virtio-scsi-dataplane.c | 9 +++++++--
hw/scsi/virtio-scsi.c | 9 +++++++--
include/hw/virtio/virtio-scsi.h | 3 +++
3 files changed, 17 insertions(+), 4 deletions(-)
diff --git a/hw/scsi/virtio-scsi-dataplane.c b/hw/scsi/virtio-scsi-dataplane.c
index 11f5705..b778e05 100644
--- a/hw/scsi/virtio-scsi-dataplane.c
+++ b/hw/scsi/virtio-scsi-dataplane.c
@@ -122,14 +122,19 @@ static void virtio_scsi_iothread_handle_cmd(EventNotifier *notifier)
VirtIOSCSIVring *vring = container_of(notifier,
VirtIOSCSIVring, host_notifier);
VirtIOSCSI *s = (VirtIOSCSI *)vring->parent;
- VirtIOSCSIReq *req;
+ VirtIOSCSIReq *req, *next;
+ QTAILQ_HEAD(, VirtIOSCSIReq) reqs = QTAILQ_HEAD_INITIALIZER(reqs);
event_notifier_test_and_clear(notifier);
while ((req = virtio_scsi_pop_req_vring(s, vring))) {
if (virtio_scsi_handle_cmd_req_prepare(s, req)) {
- virtio_scsi_handle_cmd_req_submit(s, req);
+ QTAILQ_INSERT_TAIL(&reqs, req, next);
}
}
+
+ QTAILQ_FOREACH_SAFE(req, &reqs, next, next) {
+ virtio_scsi_handle_cmd_req_submit(s, req);
+ }
}
/* Context: QEMU global mutex held */
diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c
index 6cf070f..395178e 100644
--- a/hw/scsi/virtio-scsi.c
+++ b/hw/scsi/virtio-scsi.c
@@ -502,7 +502,8 @@ static void virtio_scsi_handle_cmd(VirtIODevice *vdev, VirtQueue *vq)
{
/* use non-QOM casts in the data path */
VirtIOSCSI *s = (VirtIOSCSI *)vdev;
- VirtIOSCSIReq *req;
+ VirtIOSCSIReq *req, *next;
+ QTAILQ_HEAD(, VirtIOSCSIReq) reqs = QTAILQ_HEAD_INITIALIZER(reqs);
if (s->ctx && !s->dataplane_disabled) {
virtio_scsi_dataplane_start(s);
@@ -510,9 +511,13 @@ static void virtio_scsi_handle_cmd(VirtIODevice *vdev, VirtQueue *vq)
}
while ((req = virtio_scsi_pop_req(s, vq))) {
if (virtio_scsi_handle_cmd_req_prepare(s, req)) {
- virtio_scsi_handle_cmd_req_submit(s, req);
+ QTAILQ_INSERT_TAIL(&reqs, req, next);
}
}
+
+ QTAILQ_FOREACH_SAFE(req, &reqs, next, next) {
+ virtio_scsi_handle_cmd_req_submit(s, req);
+ }
}
static void virtio_scsi_get_config(VirtIODevice *vdev,
diff --git a/include/hw/virtio/virtio-scsi.h b/include/hw/virtio/virtio-scsi.h
index 1cc759a..6134c0b 100644
--- a/include/hw/virtio/virtio-scsi.h
+++ b/include/hw/virtio/virtio-scsi.h
@@ -213,6 +213,9 @@ typedef struct VirtIOSCSIReq {
VirtQueueElement elem;
/* Set by dataplane code. */
VirtIOSCSIVring *vring;
+ /* Used by two stages request submitting */
+ QTAILQ_ENTRY(VirtIOSCSIReq) next;
+
SCSIRequest *sreq;
size_t resp_size;
enum SCSIXferMode mode;
--
1.9.3
^ permalink raw reply related [flat|nested] 9+ messages in thread* [Qemu-devel] [PATCH v3 6/7] virtio-scsi: Call bdrv_io_plug/bdrv_io_unplug in cmd request handling
2014-09-23 7:49 [Qemu-devel] [PATCH v3 0/7] virtio-scsi: Dataplane on single iothread Fam Zheng
` (4 preceding siblings ...)
2014-09-23 7:49 ` [Qemu-devel] [PATCH v3 5/7] virtio-scsi: Batched prepare for cmd reqs Fam Zheng
@ 2014-09-23 7:49 ` Fam Zheng
2014-09-23 7:49 ` [Qemu-devel] [PATCH v3 7/7] virtio-scsi: Process ".iothread" property Fam Zheng
2014-09-23 10:33 ` [Qemu-devel] [PATCH v3 0/7] virtio-scsi: Dataplane on single iothread Paolo Bonzini
7 siblings, 0 replies; 9+ messages in thread
From: Fam Zheng @ 2014-09-23 7:49 UTC (permalink / raw)
To: qemu-devel; +Cc: kwolf, pbonzini, stefanha
Signed-off-by: Fam Zheng <famz@redhat.com>
---
hw/scsi/virtio-scsi.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c
index 395178e..09a39cb 100644
--- a/hw/scsi/virtio-scsi.c
+++ b/hw/scsi/virtio-scsi.c
@@ -488,6 +488,8 @@ bool virtio_scsi_handle_cmd_req_prepare(VirtIOSCSI *s, VirtIOSCSIReq *req)
virtio_scsi_complete_cmd_req(req);
return false;
}
+ scsi_req_ref(req->sreq);
+ bdrv_io_plug(d->conf.bs);
return true;
}
@@ -496,6 +498,8 @@ void virtio_scsi_handle_cmd_req_submit(VirtIOSCSI *s, VirtIOSCSIReq *req)
if (scsi_req_enqueue(req->sreq)) {
scsi_req_continue(req->sreq);
}
+ bdrv_io_unplug(req->sreq->dev->conf.bs);
+ scsi_req_unref(req->sreq);
}
static void virtio_scsi_handle_cmd(VirtIODevice *vdev, VirtQueue *vq)
--
1.9.3
^ permalink raw reply related [flat|nested] 9+ messages in thread* [Qemu-devel] [PATCH v3 7/7] virtio-scsi: Process ".iothread" property
2014-09-23 7:49 [Qemu-devel] [PATCH v3 0/7] virtio-scsi: Dataplane on single iothread Fam Zheng
` (5 preceding siblings ...)
2014-09-23 7:49 ` [Qemu-devel] [PATCH v3 6/7] virtio-scsi: Call bdrv_io_plug/bdrv_io_unplug in cmd request handling Fam Zheng
@ 2014-09-23 7:49 ` Fam Zheng
2014-09-23 10:33 ` [Qemu-devel] [PATCH v3 0/7] virtio-scsi: Dataplane on single iothread Paolo Bonzini
7 siblings, 0 replies; 9+ messages in thread
From: Fam Zheng @ 2014-09-23 7:49 UTC (permalink / raw)
To: qemu-devel; +Cc: kwolf, pbonzini, stefanha
We are ready, now let's effectively enable dataplane.
Signed-off-by: Fam Zheng <famz@redhat.com>
---
hw/scsi/virtio-scsi.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c
index 09a39cb..fa36e23 100644
--- a/hw/scsi/virtio-scsi.c
+++ b/hw/scsi/virtio-scsi.c
@@ -754,6 +754,10 @@ void virtio_scsi_common_realize(DeviceState *dev, Error **errp,
s->cmd_vqs[i] = virtio_add_queue(vdev, VIRTIO_SCSI_VQ_SIZE,
cmd);
}
+
+ if (s->conf.iothread) {
+ virtio_scsi_set_iothread(VIRTIO_SCSI(s), s->conf.iothread);
+ }
}
/* Disable dataplane thread during live migration since it does not
--
1.9.3
^ permalink raw reply related [flat|nested] 9+ messages in thread* Re: [Qemu-devel] [PATCH v3 0/7] virtio-scsi: Dataplane on single iothread
2014-09-23 7:49 [Qemu-devel] [PATCH v3 0/7] virtio-scsi: Dataplane on single iothread Fam Zheng
` (6 preceding siblings ...)
2014-09-23 7:49 ` [Qemu-devel] [PATCH v3 7/7] virtio-scsi: Process ".iothread" property Fam Zheng
@ 2014-09-23 10:33 ` Paolo Bonzini
7 siblings, 0 replies; 9+ messages in thread
From: Paolo Bonzini @ 2014-09-23 10:33 UTC (permalink / raw)
To: Fam Zheng, qemu-devel; +Cc: kwolf, stefanha
Il 23/09/2014 09:49, Fam Zheng ha scritto:
> The second half of previous series while rebasing on Paolo's scsi-next branch.
>
> Changes include:
>
> - Move dataplane fields from VirtIOSCSICommon to VirtIOSCSI.
> - Assert s->ctx in virtio_scsi_set_iothread.
> - No virtio_scsi_aio_acquire, just acquire/release in virtio_scsi_push_event.
> - Add migration state notifier.
> - Add bdrv_io_plug / bdrv_io_unplug.
>
> Thanks,
> Fam
>
> Fam Zheng (7):
> virtio-scsi-dataplane: Code to run virtio-scsi on iothread
> virtio-scsi: Hook up with dataplane
> virtio-scsi: Add migration state notifier for dataplane code
> virtio-scsi: Two stages processing of cmd request
> virtio-scsi: Batched prepare for cmd reqs
> virtio-scsi: Call bdrv_io_plug/bdrv_io_unplug in cmd request handling
> virtio-scsi: Process ".iothread" property
>
> hw/scsi/Makefile.objs | 2 +-
> hw/scsi/virtio-scsi-dataplane.c | 229 ++++++++++++++++++++++++++++++++++++++++
> hw/scsi/virtio-scsi.c | 116 +++++++++++++++++---
> include/hw/virtio/virtio-scsi.h | 33 +++++-
> 4 files changed, 362 insertions(+), 18 deletions(-)
> create mode 100644 hw/scsi/virtio-scsi-dataplane.c
>
Thanks, applied to scsi-next.
Paolo
^ permalink raw reply [flat|nested] 9+ messages in thread