diff mbox series

net/vhost: add flag to control wait queuing

Message ID 20220601142541.605301-1-yuanx.wang@intel.com (mailing list archive)
State Superseded, archived
Delegated to: Maxime Coquelin
Headers
Series net/vhost: add flag to control wait queuing |

Checks

Context Check Description
ci/checkpatch success coding style OK
ci/iol-mellanox-Performance success Performance Testing PASS
ci/iol-x86_64-unit-testing success Testing PASS
ci/iol-x86_64-compile-testing success Testing PASS
ci/Intel-compilation success Compilation OK
ci/github-robot: build fail github build: failed
ci/intel-Testing success Testing PASS
ci/iol-intel-Functional success Functional Testing PASS
ci/iol-intel-Performance success Performance Testing PASS
ci/iol-aarch64-unit-testing success Testing PASS
ci/iol-aarch64-compile-testing success Testing PASS
ci/iol-abi-testing success Testing PASS

Commit Message

Wang, YuanX June 1, 2022, 2:25 p.m. UTC 
  update_queuing_status prevents PMD queue operations from affecting
the data plane by waiting for rx/tx_pkt_burst to stops accessing the
vhost device.
In fact, it is only necessary to wait when destroy/stop the device,
new/start device and vring_state_changed cases do not need.

Since vring is locked when vring state changes, unconditional
waiting may also cause deadlocks.

To avoid deadlocks and unnecessary waiting, this patch adds a flag to
control whether waiting is required.

Fixes: 9dc6bb0682 (net/vhost: fix access to freed memory)
Fixes: 1ce3c7fe14 (net/vhost: emulate device start/stop behavior)
Cc: stable@dpdk.org

Signed-off-by: Yuan Wang <yuanx.wang@intel.com>
---
 drivers/net/vhost/rte_eth_vhost.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

Comments

Ling, WeiX June 2, 2022, 8:32 a.m. UTC | #1 
> -----Original Message-----
> From: Yuan Wang <yuanx.wang@intel.com>
> Sent: Wednesday, June 1, 2022 10:26 PM
> To: maxime.coquelin@redhat.com; Xia, Chenbo <chenbo.xia@intel.com>;
> dev@dpdk.org
> Cc: Hu, Jiayu <jiayu.hu@intel.com>; He, Xingguang
> <xingguang.he@intel.com>; Wang, YuanX <yuanx.wang@intel.com>;
> stable@dpdk.org
> Subject: [PATCH] net/vhost: add flag to control wait queuing
> 
> update_queuing_status prevents PMD queue operations from affecting the
> data plane by waiting for rx/tx_pkt_burst to stops accessing the vhost device.
> In fact, it is only necessary to wait when destroy/stop the device, new/start
> device and vring_state_changed cases do not need.
> 
> Since vring is locked when vring state changes, unconditional waiting may
> also cause deadlocks.
> 
> To avoid deadlocks and unnecessary waiting, this patch adds a flag to control
> whether waiting is required.
> 
> Fixes: 9dc6bb0682 (net/vhost: fix access to freed memory)
> Fixes: 1ce3c7fe14 (net/vhost: emulate device start/stop behavior)
> Cc: stable@dpdk.org
> 
> Signed-off-by: Yuan Wang <yuanx.wang@intel.com>
> ---

Tested-by: Wei Ling <weix.ling@intel.com>
diff mbox series

Patch

diff --git a/drivers/net/vhost/rte_eth_vhost.c b/drivers/net/vhost/rte_eth_vhost.c
index a248a65df4..a280e788fb 100644
--- a/drivers/net/vhost/rte_eth_vhost.c
+++ b/drivers/net/vhost/rte_eth_vhost.c
@@ -716,7 +716,7 @@  eth_vhost_install_intr(struct rte_eth_dev *dev)
 }
 
 static void
-update_queuing_status(struct rte_eth_dev *dev)
+update_queuing_status(struct rte_eth_dev *dev, bool wait_queuing)
 {
 	struct pmd_internal *internal = dev->data->dev_private;
 	struct vhost_queue *vq;
@@ -742,7 +742,7 @@  update_queuing_status(struct rte_eth_dev *dev)
 			rte_atomic32_set(&vq->allow_queuing, 1);
 		else
 			rte_atomic32_set(&vq->allow_queuing, 0);
-		while (rte_atomic32_read(&vq->while_queuing))
+		while (wait_queuing && rte_atomic32_read(&vq->while_queuing))
 			rte_pause();
 	}
 
@@ -754,7 +754,7 @@  update_queuing_status(struct rte_eth_dev *dev)
 			rte_atomic32_set(&vq->allow_queuing, 1);
 		else
 			rte_atomic32_set(&vq->allow_queuing, 0);
-		while (rte_atomic32_read(&vq->while_queuing))
+		while (wait_queuing && rte_atomic32_read(&vq->while_queuing))
 			rte_pause();
 	}
 }
@@ -836,7 +836,7 @@  new_device(int vid)
 	eth_dev->data->dev_link.link_status = RTE_ETH_LINK_UP;
 
 	rte_atomic32_set(&internal->dev_attached, 1);
-	update_queuing_status(eth_dev);
+	update_queuing_status(eth_dev, false);
 
 	VHOST_LOG(INFO, "Vhost device %d created\n", vid);
 
@@ -866,7 +866,7 @@  destroy_device(int vid)
 	internal = eth_dev->data->dev_private;
 
 	rte_atomic32_set(&internal->dev_attached, 0);
-	update_queuing_status(eth_dev);
+	update_queuing_status(eth_dev, true);
 
 	eth_dev->data->dev_link.link_status = RTE_ETH_LINK_DOWN;
 
@@ -976,7 +976,7 @@  vring_state_changed(int vid, uint16_t vring, int enable)
 	state->max_vring = RTE_MAX(vring, state->max_vring);
 	rte_spinlock_unlock(&state->lock);
 
-	update_queuing_status(eth_dev);
+	update_queuing_status(eth_dev, false);
 
 	VHOST_LOG(INFO, "vring%u is %s\n",
 			vring, enable ? "enabled" : "disabled");
@@ -1163,7 +1163,7 @@  eth_dev_start(struct rte_eth_dev *eth_dev)
 	}
 
 	rte_atomic32_set(&internal->started, 1);
-	update_queuing_status(eth_dev);
+	update_queuing_status(eth_dev, false);
 
 	return 0;
 }
@@ -1175,7 +1175,7 @@  eth_dev_stop(struct rte_eth_dev *dev)
 
 	dev->data->dev_started = 0;
 	rte_atomic32_set(&internal->started, 0);
-	update_queuing_status(dev);
+	update_queuing_status(dev, true);
 
 	return 0;
 }