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From: Xiao Wang <xiao.w.wang@intel.com>
To: tiwei.bie@intel.com, maxime.coquelin@redhat.com
Cc: alejandro.lucero@netronome.com, dev@dpdk.org,
	zhihong.wang@intel.com, xiaolong.ye@intel.com,
	Xiao Wang <xiao.w.wang@intel.com>
Subject: [dpdk-dev] [PATCH v4 09/10] net/ifc: support SW assisted VDPA live migration
Date: Sat, 15 Dec 2018 05:16:11 +0800	[thread overview]
Message-ID: <20181214211612.167681-10-xiao.w.wang@intel.com> (raw)
In-Reply-To: <20181214211612.167681-1-xiao.w.wang@intel.com>

In SW assisted live migration mode, driver will stop the device and
setup a mediate virtio ring to relay the communication between the
virtio driver and the VDPA device.

This data path intervention will allow SW to help on guest dirty page
logging for live migration.

This SW fallback is event driven relay thread, so when the network
throughput is low, this SW fallback will take little CPU resource, but
when the throughput goes up, the relay thread's CPU usage will goes up
accordinly.

User needs to take all the factors including CPU usage, guest perf
degradation, etc. into consideration when selecting the live migration
support mode.

Signed-off-by: Xiao Wang <xiao.w.wang@intel.com>
---
 drivers/net/ifc/base/ifcvf.h |   1 +
 drivers/net/ifc/ifcvf_vdpa.c | 346 ++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 344 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ifc/base/ifcvf.h b/drivers/net/ifc/base/ifcvf.h
index c15c69107..e8a30d2c6 100644
--- a/drivers/net/ifc/base/ifcvf.h
+++ b/drivers/net/ifc/base/ifcvf.h
@@ -50,6 +50,7 @@
 #define IFCVF_LM_ENABLE_VF		0x1
 #define IFCVF_LM_ENABLE_PF		0x3
 #define IFCVF_LOG_BASE			0x100000000000
+#define IFCVF_MEDIATE_VRING		0x200000000000
 
 #define IFCVF_32_BIT_MASK		0xffffffff
 
diff --git a/drivers/net/ifc/ifcvf_vdpa.c b/drivers/net/ifc/ifcvf_vdpa.c
index f181c5a6e..61757d0b4 100644
--- a/drivers/net/ifc/ifcvf_vdpa.c
+++ b/drivers/net/ifc/ifcvf_vdpa.c
@@ -63,6 +63,9 @@ struct ifcvf_internal {
 	rte_atomic32_t running;
 	rte_spinlock_t lock;
 	bool sw_lm;
+	bool sw_fallback_running;
+	/* mediated vring for sw fallback */
+	struct vring m_vring[IFCVF_MAX_QUEUES * 2];
 };
 
 struct internal_list {
@@ -308,6 +311,9 @@ vdpa_ifcvf_stop(struct ifcvf_internal *internal)
 		rte_vhost_set_vring_base(vid, i, hw->vring[i].last_avail_idx,
 				hw->vring[i].last_used_idx);
 
+	if (internal->sw_lm)
+		return;
+
 	rte_vhost_get_negotiated_features(vid, &features);
 	if (RTE_VHOST_NEED_LOG(features)) {
 		ifcvf_disable_logging(hw);
@@ -539,6 +545,318 @@ update_datapath(struct ifcvf_internal *internal)
 	return ret;
 }
 
+static int
+m_ifcvf_start(struct ifcvf_internal *internal)
+{
+	struct ifcvf_hw *hw = &internal->hw;
+	uint32_t i, nr_vring;
+	int vid, ret;
+	struct rte_vhost_vring vq;
+	void *vring_buf;
+	uint64_t m_vring_iova = IFCVF_MEDIATE_VRING;
+	uint64_t size;
+	uint64_t gpa;
+
+	vid = internal->vid;
+	nr_vring = rte_vhost_get_vring_num(vid);
+	rte_vhost_get_negotiated_features(vid, &hw->req_features);
+
+	for (i = 0; i < nr_vring; i++) {
+		rte_vhost_get_vhost_vring(vid, i, &vq);
+
+		size = RTE_ALIGN_CEIL(vring_size(vq.size, PAGE_SIZE),
+				PAGE_SIZE);
+		vring_buf = rte_zmalloc("ifcvf", size, PAGE_SIZE);
+		vring_init(&internal->m_vring[i], vq.size, vring_buf,
+				PAGE_SIZE);
+
+		ret = rte_vfio_container_dma_map(internal->vfio_container_fd,
+			(uint64_t)(uintptr_t)vring_buf, m_vring_iova, size);
+		if (ret < 0) {
+			DRV_LOG(ERR, "mediate vring DMA map failed.");
+			goto error;
+		}
+
+		gpa = hva_to_gpa(vid, (uint64_t)(uintptr_t)vq.desc);
+		if (gpa == 0) {
+			DRV_LOG(ERR, "Fail to get GPA for descriptor ring.");
+			return -1;
+		}
+		hw->vring[i].desc = gpa;
+
+		hw->vring[i].avail = m_vring_iova +
+			(char *)internal->m_vring[i].avail -
+			(char *)internal->m_vring[i].desc;
+
+		hw->vring[i].used = m_vring_iova +
+			(char *)internal->m_vring[i].used -
+			(char *)internal->m_vring[i].desc;
+
+		hw->vring[i].size = vq.size;
+
+		rte_vhost_get_vring_base(vid, i, &hw->vring[i].last_avail_idx,
+				&hw->vring[i].last_used_idx);
+
+		m_vring_iova += size;
+	}
+	hw->nr_vring = nr_vring;
+
+	return ifcvf_start_hw(&internal->hw);
+
+error:
+	for (i = 0; i < nr_vring; i++)
+		if (internal->m_vring[i].desc)
+			rte_free(internal->m_vring[i].desc);
+
+	return -1;
+}
+
+static int
+m_ifcvf_stop(struct ifcvf_internal *internal)
+{
+	int vid;
+	uint32_t i;
+	struct rte_vhost_vring vq;
+	struct ifcvf_hw *hw = &internal->hw;
+	uint64_t m_vring_iova = IFCVF_MEDIATE_VRING;
+	uint64_t size, len;
+
+	vid = internal->vid;
+	ifcvf_stop_hw(hw);
+
+	for (i = 0; i < hw->nr_vring; i++) {
+		rte_vhost_get_vhost_vring(vid, i, &vq);
+		len = IFCVF_USED_RING_LEN(vq.size);
+		rte_vhost_log_used_vring(vid, i, 0, len);
+
+		size = RTE_ALIGN_CEIL(vring_size(vq.size, PAGE_SIZE),
+				PAGE_SIZE);
+		rte_vfio_container_dma_unmap(internal->vfio_container_fd,
+			(uint64_t)(uintptr_t)internal->m_vring[i].desc,
+			m_vring_iova, size);
+
+		rte_vhost_set_vring_base(vid, i, hw->vring[i].last_avail_idx,
+				hw->vring[i].last_used_idx);
+		rte_free(internal->m_vring[i].desc);
+		m_vring_iova += size;
+	}
+
+	return 0;
+}
+
+static int
+m_enable_vfio_intr(struct ifcvf_internal *internal)
+{
+	uint32_t nr_vring;
+	struct rte_intr_handle *intr_handle = &internal->pdev->intr_handle;
+	int ret;
+
+	nr_vring = rte_vhost_get_vring_num(internal->vid);
+
+	ret = rte_intr_efd_enable(intr_handle, nr_vring);
+	if (ret)
+		return -1;
+
+	ret = rte_intr_enable(intr_handle);
+	if (ret)
+		return -1;
+
+	return 0;
+}
+
+static void
+m_disable_vfio_intr(struct ifcvf_internal *internal)
+{
+	struct rte_intr_handle *intr_handle = &internal->pdev->intr_handle;
+
+	rte_intr_efd_disable(intr_handle);
+	rte_intr_disable(intr_handle);
+}
+
+static void
+update_avail_ring(struct ifcvf_internal *internal, uint16_t qid)
+{
+	rte_vdpa_relay_vring_avail(internal->vid, qid, &internal->m_vring[qid]);
+	ifcvf_notify_queue(&internal->hw, qid);
+}
+
+static void
+update_used_ring(struct ifcvf_internal *internal, uint16_t qid)
+{
+	rte_vdpa_relay_vring_used(internal->vid, qid, &internal->m_vring[qid]);
+	rte_vhost_vring_call(internal->vid, qid);
+}
+
+static void *
+vring_relay(void *arg)
+{
+	int i, vid, epfd, fd, nfds;
+	struct ifcvf_internal *internal = (struct ifcvf_internal *)arg;
+	struct rte_vhost_vring vring;
+	struct rte_intr_handle *intr_handle;
+	uint16_t qid, q_num;
+	struct epoll_event events[IFCVF_MAX_QUEUES * 4];
+	struct epoll_event ev;
+	int nbytes;
+	uint64_t buf;
+
+	vid = internal->vid;
+	q_num = rte_vhost_get_vring_num(vid);
+	/* prepare the mediate vring */
+	for (qid = 0; qid < q_num; qid++) {
+		rte_vhost_get_vring_base(vid, qid,
+				&internal->m_vring[qid].avail->idx,
+				&internal->m_vring[qid].used->idx);
+		rte_vdpa_relay_vring_avail(vid, qid, &internal->m_vring[qid]);
+	}
+
+	/* add notify fd and interrupt fd to epoll */
+	epfd = epoll_create(IFCVF_MAX_QUEUES * 2);
+	if (epfd < 0) {
+		DRV_LOG(ERR, "failed to create epoll instance.");
+		return NULL;
+	}
+	internal->epfd = epfd;
+
+	for (qid = 0; qid < q_num; qid++) {
+		ev.events = EPOLLIN | EPOLLPRI;
+		rte_vhost_get_vhost_vring(vid, qid, &vring);
+		ev.data.u64 = qid << 1 | (uint64_t)vring.kickfd << 32;
+		if (epoll_ctl(epfd, EPOLL_CTL_ADD, vring.kickfd, &ev) < 0) {
+			DRV_LOG(ERR, "epoll add error: %s", strerror(errno));
+			return NULL;
+		}
+	}
+
+	intr_handle = &internal->pdev->intr_handle;
+	for (qid = 0; qid < q_num; qid++) {
+		ev.events = EPOLLIN | EPOLLPRI;
+		ev.data.u64 = 1 | qid << 1 |
+			(uint64_t)intr_handle->efds[qid] << 32;
+		if (epoll_ctl(epfd, EPOLL_CTL_ADD, intr_handle->efds[qid], &ev)
+				< 0) {
+			DRV_LOG(ERR, "epoll add error: %s", strerror(errno));
+			return NULL;
+		}
+	}
+
+	/* start relay with a first kick */
+	for (qid = 0; qid < q_num; qid++)
+		ifcvf_notify_queue(&internal->hw, qid);
+
+	/* listen to the events and react accordingly */
+	for (;;) {
+		nfds = epoll_wait(epfd, events, q_num * 2, -1);
+		if (nfds < 0) {
+			if (errno == EINTR)
+				continue;
+			DRV_LOG(ERR, "epoll_wait return fail\n");
+			return NULL;
+		}
+
+		for (i = 0; i < nfds; i++) {
+			fd = (uint32_t)(events[i].data.u64 >> 32);
+			do {
+				nbytes = read(fd, &buf, 8);
+				if (nbytes < 0) {
+					if (errno == EINTR ||
+					    errno == EWOULDBLOCK ||
+					    errno == EAGAIN)
+						continue;
+					DRV_LOG(INFO, "Error reading "
+						"kickfd: %s",
+						strerror(errno));
+				}
+				break;
+			} while (1);
+
+			qid = events[i].data.u32 >> 1;
+
+			if (events[i].data.u32 & 1)
+				update_used_ring(internal, qid);
+			else
+				update_avail_ring(internal, qid);
+		}
+	}
+
+	return NULL;
+}
+
+static int
+setup_vring_relay(struct ifcvf_internal *internal)
+{
+	int ret;
+
+	ret = pthread_create(&internal->tid, NULL, vring_relay,
+			(void *)internal);
+	if (ret) {
+		DRV_LOG(ERR, "failed to create ring relay pthread.");
+		return -1;
+	}
+	return 0;
+}
+
+static int
+unset_vring_relay(struct ifcvf_internal *internal)
+{
+	void *status;
+
+	if (internal->tid) {
+		pthread_cancel(internal->tid);
+		pthread_join(internal->tid, &status);
+	}
+	internal->tid = 0;
+
+	if (internal->epfd >= 0)
+		close(internal->epfd);
+	internal->epfd = -1;
+
+	return 0;
+}
+
+static int
+ifcvf_sw_fallback_switchover(struct ifcvf_internal *internal)
+{
+	int ret;
+
+	/* stop the direct IO data path */
+	unset_notify_relay(internal);
+	vdpa_ifcvf_stop(internal);
+	vdpa_disable_vfio_intr(internal);
+
+	ret = rte_vhost_host_notifier_ctrl(internal->vid, false);
+	if (ret && ret != -ENOTSUP)
+		goto error;
+
+	/* set up interrupt for interrupt relay */
+	ret = m_enable_vfio_intr(internal);
+	if (ret)
+		goto unmap;
+
+	/* config the VF */
+	ret = m_ifcvf_start(internal);
+	if (ret)
+		goto unset_intr;
+
+	/* set up vring relay thread */
+	ret = setup_vring_relay(internal);
+	if (ret)
+		goto stop_vf;
+
+	internal->sw_fallback_running = true;
+
+	return 0;
+
+stop_vf:
+	m_ifcvf_stop(internal);
+unset_intr:
+	m_disable_vfio_intr(internal);
+unmap:
+	ifcvf_dma_map(internal, 0);
+error:
+	return -1;
+}
+
 static int
 ifcvf_dev_config(int vid)
 {
@@ -579,8 +897,25 @@ ifcvf_dev_close(int vid)
 	}
 
 	internal = list->internal;
-	rte_atomic32_set(&internal->dev_attached, 0);
-	update_datapath(internal);
+
+	if (internal->sw_fallback_running) {
+		/* unset ring relay */
+		unset_vring_relay(internal);
+
+		/* reset VF */
+		m_ifcvf_stop(internal);
+
+		/* remove interrupt setting */
+		m_disable_vfio_intr(internal);
+
+		/* unset DMA map for guest memory */
+		ifcvf_dma_map(internal, 0);
+
+		internal->sw_fallback_running = false;
+	} else {
+		rte_atomic32_set(&internal->dev_attached, 0);
+		update_datapath(internal);
+	}
 
 	return 0;
 }
@@ -604,7 +939,12 @@ ifcvf_set_features(int vid)
 	internal = list->internal;
 	rte_vhost_get_negotiated_features(vid, &features);
 
-	if (RTE_VHOST_NEED_LOG(features)) {
+	if (!RTE_VHOST_NEED_LOG(features))
+		return 0;
+
+	if (internal->sw_lm) {
+		ifcvf_sw_fallback_switchover(internal);
+	} else {
 		rte_vhost_get_log_base(vid, &log_base, &log_size);
 		rte_vfio_container_dma_map(internal->vfio_container_fd,
 				log_base, IFCVF_LOG_BASE, log_size);
-- 
2.15.1

  parent reply	other threads:[~2018-12-14 21:26 UTC|newest]

Thread overview: 86+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-11-28  9:45 [dpdk-dev] [PATCH 0/9] " Xiao Wang
2018-11-28  9:45 ` [dpdk-dev] [PATCH 1/9] vhost: provide helper for host notifier ctrl Xiao Wang
2018-11-28  9:46 ` [dpdk-dev] [PATCH 2/9] vhost: provide helpers for virtio ring relay Xiao Wang
2018-12-04  6:22   ` Tiwei Bie
2018-12-12  6:51     ` Wang, Xiao W
2018-12-13  1:10   ` [dpdk-dev] [PATCH v2 0/9] support SW assisted VDPA live migration Xiao Wang
2018-12-13  1:10     ` [dpdk-dev] [PATCH v2 1/9] vhost: provide helper for host notifier ctrl Xiao Wang
2018-12-13  1:10     ` [dpdk-dev] [PATCH v2 2/9] vhost: provide helpers for virtio ring relay Xiao Wang
2018-12-13 10:09       ` [dpdk-dev] [PATCH v3 0/9] support SW assisted VDPA live migration Xiao Wang
2018-12-13 10:09         ` [dpdk-dev] [PATCH v3 1/9] vhost: provide helper for host notifier ctrl Xiao Wang
2018-12-14 13:33           ` Maxime Coquelin
2018-12-14 19:05             ` Wang, Xiao W
2018-12-14 21:16           ` [dpdk-dev] [PATCH v4 00/10] support SW assisted VDPA live migration Xiao Wang
2018-12-14 21:16             ` [dpdk-dev] [PATCH v4 01/10] vhost: remove unused internal API Xiao Wang
2018-12-16  8:58               ` Maxime Coquelin
2018-12-14 21:16             ` [dpdk-dev] [PATCH v4 02/10] vhost: provide helper for host notifier ctrl Xiao Wang
2018-12-16  9:00               ` Maxime Coquelin
2018-12-14 21:16             ` [dpdk-dev] [PATCH v4 03/10] vhost: provide helpers for virtio ring relay Xiao Wang
2018-12-16  9:10               ` Maxime Coquelin
2018-12-17  8:51                 ` Wang, Xiao W
2018-12-17 11:02                   ` Maxime Coquelin
2018-12-17 14:41                     ` Wang, Xiao W
2018-12-17 19:00                       ` Maxime Coquelin
2018-12-18  8:27                         ` Wang, Xiao W
2018-12-18  8:44                           ` Thomas Monjalon
2018-12-18  8:01               ` [dpdk-dev] [PATCH v5 00/10] support SW assisted VDPA live migration Xiao Wang
2018-12-18  8:01                 ` [dpdk-dev] [PATCH v5 01/10] vhost: remove unused internal API Xiao Wang
2018-12-18  8:01                 ` [dpdk-dev] [PATCH v5 02/10] vhost: provide helper for host notifier ctrl Xiao Wang
2018-12-18 15:37                   ` Ferruh Yigit
2018-12-18  8:02                 ` [dpdk-dev] [PATCH v5 03/10] vhost: provide helpers for virtio ring relay Xiao Wang
2018-12-18  8:02                 ` [dpdk-dev] [PATCH v5 04/10] net/ifc: dump debug message for error Xiao Wang
2018-12-18  8:02                 ` [dpdk-dev] [PATCH v5 05/10] net/ifc: store only registered device instance Xiao Wang
2018-12-18  8:02                 ` [dpdk-dev] [PATCH v5 06/10] net/ifc: detect if VDPA mode is specified Xiao Wang
2018-12-18  8:02                 ` [dpdk-dev] [PATCH v5 07/10] net/ifc: add devarg for LM mode Xiao Wang
2018-12-18 11:23                   ` Maxime Coquelin
2018-12-18  8:02                 ` [dpdk-dev] [PATCH v5 08/10] net/ifc: use lib API for used ring logging Xiao Wang
2018-12-18  8:02                 ` [dpdk-dev] [PATCH v5 09/10] net/ifc: support SW assisted VDPA live migration Xiao Wang
2018-12-18 11:33                   ` Maxime Coquelin
2018-12-18  8:02                 ` [dpdk-dev] [PATCH v5 10/10] doc: update ifc NIC document Xiao Wang
2018-12-18 11:35                   ` Maxime Coquelin
2018-12-14 21:16             ` [dpdk-dev] [PATCH v4 04/10] net/ifc: dump debug message for error Xiao Wang
2018-12-16  9:11               ` Maxime Coquelin
2018-12-14 21:16             ` [dpdk-dev] [PATCH v4 05/10] net/ifc: store only registered device instance Xiao Wang
2018-12-16  9:12               ` Maxime Coquelin
2018-12-14 21:16             ` [dpdk-dev] [PATCH v4 06/10] net/ifc: detect if VDPA mode is specified Xiao Wang
2018-12-16  9:17               ` Maxime Coquelin
2018-12-17  8:54                 ` Wang, Xiao W
2018-12-14 21:16             ` [dpdk-dev] [PATCH v4 07/10] net/ifc: add devarg for LM mode Xiao Wang
2018-12-16  9:21               ` Maxime Coquelin
2018-12-17  9:00                 ` Wang, Xiao W
2018-12-14 21:16             ` [dpdk-dev] [PATCH v4 08/10] net/ifc: use lib API for used ring logging Xiao Wang
2018-12-16  9:24               ` Maxime Coquelin
2018-12-14 21:16             ` Xiao Wang [this message]
2018-12-16  9:35               ` [dpdk-dev] [PATCH v4 09/10] net/ifc: support SW assisted VDPA live migration Maxime Coquelin
2018-12-17  9:12                 ` Wang, Xiao W
2018-12-17 11:08                   ` Maxime Coquelin
2018-12-14 21:16             ` [dpdk-dev] [PATCH v4 10/10] doc: update ifc NIC document Xiao Wang
2018-12-16  9:36               ` Maxime Coquelin
2018-12-17  9:15                 ` Wang, Xiao W
2018-12-18 14:01             ` [dpdk-dev] [PATCH v4 00/10] support SW assisted VDPA live migration Maxime Coquelin
2018-12-13 10:09         ` [dpdk-dev] [PATCH v3 2/9] vhost: provide helpers for virtio ring relay Xiao Wang
2018-12-13 10:09         ` [dpdk-dev] [PATCH v3 3/9] net/ifc: dump debug message for error Xiao Wang
2018-12-13 10:09         ` [dpdk-dev] [PATCH v3 4/9] net/ifc: store only registered device instance Xiao Wang
2018-12-13 10:09         ` [dpdk-dev] [PATCH v3 5/9] net/ifc: detect if VDPA mode is specified Xiao Wang
2018-12-13 10:09         ` [dpdk-dev] [PATCH v3 6/9] net/ifc: add devarg for LM mode Xiao Wang
2018-12-13 10:09         ` [dpdk-dev] [PATCH v3 7/9] net/ifc: use lib API for used ring logging Xiao Wang
2018-12-13 10:09         ` [dpdk-dev] [PATCH v3 8/9] net/ifc: support SW assisted VDPA live migration Xiao Wang
2018-12-13 10:09         ` [dpdk-dev] [PATCH v3 9/9] doc: update ifc NIC document Xiao Wang
2018-12-13  1:10     ` [dpdk-dev] [PATCH v2 3/9] net/ifc: dump debug message for error Xiao Wang
2018-12-13  1:10     ` [dpdk-dev] [PATCH v2 4/9] net/ifc: store only registered device instance Xiao Wang
2018-12-13  1:10     ` [dpdk-dev] [PATCH v2 5/9] net/ifc: detect if VDPA mode is specified Xiao Wang
2018-12-13  1:10     ` [dpdk-dev] [PATCH v2 6/9] net/ifc: add devarg for LM mode Xiao Wang
2018-12-13  1:10     ` [dpdk-dev] [PATCH v2 7/9] net/ifc: use lib API for used ring logging Xiao Wang
2018-12-13  1:10     ` [dpdk-dev] [PATCH v2 8/9] net/ifc: support SW assisted VDPA live migration Xiao Wang
2018-12-13  1:10     ` [dpdk-dev] [PATCH v2 9/9] doc: update ifc NIC document Xiao Wang
2018-11-28  9:46 ` [dpdk-dev] [PATCH 3/9] net/ifc: dump debug message for error Xiao Wang
2018-11-28  9:46 ` [dpdk-dev] [PATCH 4/9] net/ifc: store only registered device instance Xiao Wang
2018-11-28  9:46 ` [dpdk-dev] [PATCH 5/9] net/ifc: detect if VDPA mode is specified Xiao Wang
2018-11-28  9:46 ` [dpdk-dev] [PATCH 6/9] net/ifc: add devarg for LM mode Xiao Wang
2018-12-04  6:31   ` Tiwei Bie
2018-12-12  6:53     ` Wang, Xiao W
2018-12-12 10:15   ` Alejandro Lucero
2018-12-12 10:23     ` Wang, Xiao W
2018-11-28  9:46 ` [dpdk-dev] [PATCH 7/9] net/ifc: use lib API for used ring logging Xiao Wang
2018-11-28  9:46 ` [dpdk-dev] [PATCH 8/9] net/ifc: support SW assisted VDPA live migration Xiao Wang
2018-11-28  9:46 ` [dpdk-dev] [PATCH 9/9] doc: update ifc NIC document Xiao Wang

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