net/mlx5: fix Rx interrupts management

This commit addresses various issues that may lead to undefined behavior
when configuring Rx interrupts.

While failure to create a Rx queue completion channel in rxq_ctrl_setup()
prevents that queue from being created, existing queues still have theirs.
Since the error handler disables dev_conf.intr_conf.rxq as well, subsequent
calls to rxq_ctrl_setup() create Rx queues without interrupts. This leads
to a scenario where not all Rx queues support interrupts; missing checks on
the presence of completion channels may crash the application.

Considering that the PMD is not supposed to disable user-provided
configuration parameters (dev_conf.intr_conf.rxq), and that these can
change for subsequent rxq_ctrl_setup() calls anyway, properly supporting a
mixed mode where not all Rx queues have interrupts enabled is a better
approach.

To do so with a minimum set of changes, priv_intr_efd_enable() and
priv_create_intr_vec() are first refactored as a single
priv_rx_intr_vec_enable() function (same for their "disable" counterparts).
Since they had to be used together, there was no point in keeping them
separate.

Remaining changes:

- Always clean up before reconfiguring interrupts to avoid memory leaks.
- Always clean up when closing the device.
- Use malloc()/free() instead of their rte_*() counterparts since there is
  no need to store the vector in huge pages-backed memory.
- Allow more Rx queues than the size of the event file descriptor array as
  long as Rx interrupts are not requested on all of them.
- Properly clean up interrupt handle when disabling Rx interrupts (nb_efd
  and intr_vec reset to 0).
- Check completion channel presence while toggling Rx interrupts on a given
  queue.

Fixes: 3c7d44af25 ("net/mlx5: support user space Rx interrupt event")
Cc: stable@dpdk.org

Signed-off-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>
This commit is contained in:
Adrien Mazarguil 2017-06-14 13:49:17 +02:00 committed by Ferruh Yigit
parent ad883aa293
commit e1016cb733
3 changed files with 78 additions and 99 deletions

View File

@ -980,10 +980,10 @@ rxq_ctrl_setup(struct rte_eth_dev *dev, struct rxq_ctrl *rxq_ctrl,
if (dev->data->dev_conf.intr_conf.rxq) {
tmpl.channel = ibv_create_comp_channel(priv->ctx);
if (tmpl.channel == NULL) {
dev->data->dev_conf.intr_conf.rxq = 0;
ret = ENOMEM;
ERROR("%p: Comp Channel creation failure: %s",
(void *)dev, strerror(ret));
ERROR("%p: Rx interrupt completion channel creation"
" failure: %s",
(void *)dev, strerror(ret));
goto error;
}
}
@ -1312,124 +1312,102 @@ mlx5_rx_burst_secondary_setup(void *dpdk_rxq, struct rte_mbuf **pkts,
}
/**
* Fill epoll fd list for rxq interrupts.
* Allocate queue vector and fill epoll fd list for Rx interrupts.
*
* @param priv
* Private structure.
* Pointer to private structure.
*
* @return
* 0 on success, negative on failure.
*/
int
priv_intr_efd_enable(struct priv *priv)
priv_rx_intr_vec_enable(struct priv *priv)
{
unsigned int i;
unsigned int rxqs_n = priv->rxqs_n;
unsigned int n = RTE_MIN(rxqs_n, (uint32_t)RTE_MAX_RXTX_INTR_VEC_ID);
unsigned int count = 0;
struct rte_intr_handle *intr_handle = priv->dev->intr_handle;
if (n == 0)
if (!priv->dev->data->dev_conf.intr_conf.rxq)
return 0;
if (n < rxqs_n) {
WARN("rxqs num is larger than EAL max interrupt vector "
"%u > %u unable to supprt rxq interrupts",
rxqs_n, (uint32_t)RTE_MAX_RXTX_INTR_VEC_ID);
return -EINVAL;
priv_rx_intr_vec_disable(priv);
intr_handle->intr_vec = malloc(sizeof(intr_handle->intr_vec[rxqs_n]));
if (intr_handle->intr_vec == NULL) {
ERROR("failed to allocate memory for interrupt vector,"
" Rx interrupts will not be supported");
return -ENOMEM;
}
intr_handle->type = RTE_INTR_HANDLE_EXT;
for (i = 0; i != n; ++i) {
struct rxq *rxq = (*priv->rxqs)[i];
struct rxq_ctrl *rxq_ctrl =
container_of(rxq, struct rxq_ctrl, rxq);
int fd = rxq_ctrl->channel->fd;
int fd;
int flags;
int rc;
/* Skip queues that cannot request interrupts. */
if (!rxq || !rxq_ctrl->channel) {
/* Use invalid intr_vec[] index to disable entry. */
intr_handle->intr_vec[i] =
RTE_INTR_VEC_RXTX_OFFSET +
RTE_MAX_RXTX_INTR_VEC_ID;
continue;
}
if (count >= RTE_MAX_RXTX_INTR_VEC_ID) {
ERROR("too many Rx queues for interrupt vector size"
" (%d), Rx interrupts cannot be enabled",
RTE_MAX_RXTX_INTR_VEC_ID);
priv_rx_intr_vec_disable(priv);
return -1;
}
fd = rxq_ctrl->channel->fd;
flags = fcntl(fd, F_GETFL);
rc = fcntl(fd, F_SETFL, flags | O_NONBLOCK);
if (rc < 0) {
WARN("failed to change rxq interrupt file "
"descriptor %d for queue index %d", fd, i);
ERROR("failed to make Rx interrupt file descriptor"
" %d non-blocking for queue index %d", fd, i);
priv_rx_intr_vec_disable(priv);
return -1;
}
intr_handle->efds[i] = fd;
intr_handle->intr_vec[i] = RTE_INTR_VEC_RXTX_OFFSET + count;
intr_handle->efds[count] = fd;
count++;
}
intr_handle->nb_efd = n;
if (!count)
priv_rx_intr_vec_disable(priv);
else
intr_handle->nb_efd = count;
return 0;
}
/**
* Clean epoll fd list for rxq interrupts.
* Clean up Rx interrupts handler.
*
* @param priv
* Private structure.
* Pointer to private structure.
*/
void
priv_intr_efd_disable(struct priv *priv)
priv_rx_intr_vec_disable(struct priv *priv)
{
struct rte_intr_handle *intr_handle = priv->dev->intr_handle;
rte_intr_free_epoll_fd(intr_handle);
}
/**
* Create and init interrupt vector array.
*
* @param priv
* Private structure.
*
* @return
* 0 on success, negative on failure.
*/
int
priv_create_intr_vec(struct priv *priv)
{
unsigned int rxqs_n = priv->rxqs_n;
unsigned int i;
struct rte_intr_handle *intr_handle = priv->dev->intr_handle;
if (rxqs_n == 0)
return 0;
intr_handle->intr_vec = (int *)
rte_malloc("intr_vec", rxqs_n * sizeof(int), 0);
if (intr_handle->intr_vec == NULL) {
WARN("Failed to allocate memory for intr_vec "
"rxq interrupt will not be supported");
return -ENOMEM;
}
for (i = 0; i != rxqs_n; ++i) {
/* 1:1 mapping between rxq and interrupt. */
intr_handle->intr_vec[i] = RTE_INTR_VEC_RXTX_OFFSET + i;
}
return 0;
}
/**
* Destroy init interrupt vector array.
*
* @param priv
* Private structure.
*
* @return
* 0 on success, negative on failure.
*/
void
priv_destroy_intr_vec(struct priv *priv)
{
struct rte_intr_handle *intr_handle = priv->dev->intr_handle;
rte_free(intr_handle->intr_vec);
free(intr_handle->intr_vec);
intr_handle->nb_efd = 0;
intr_handle->intr_vec = NULL;
}
#ifdef HAVE_UPDATE_CQ_CI
/**
* DPDK callback for rx queue interrupt enable.
* DPDK callback for Rx queue interrupt enable.
*
* @param dev
* Pointer to Ethernet device structure.
* @param rx_queue_id
* RX queue number.
* Rx queue number.
*
* @return
* 0 on success, negative on failure.
@ -1440,24 +1418,26 @@ mlx5_rx_intr_enable(struct rte_eth_dev *dev, uint16_t rx_queue_id)
struct priv *priv = mlx5_get_priv(dev);
struct rxq *rxq = (*priv->rxqs)[rx_queue_id];
struct rxq_ctrl *rxq_ctrl = container_of(rxq, struct rxq_ctrl, rxq);
struct ibv_cq *cq = rxq_ctrl->cq;
uint16_t ci = rxq->cq_ci;
int ret = 0;
int ret;
ibv_mlx5_exp_update_cq_ci(cq, ci);
ret = ibv_req_notify_cq(cq, 0);
if (!rxq || !rxq_ctrl->channel) {
ret = EINVAL;
} else {
ibv_mlx5_exp_update_cq_ci(rxq_ctrl->cq, rxq->cq_ci);
ret = ibv_req_notify_cq(rxq_ctrl->cq, 0);
}
if (ret)
WARN("unable to arm interrupt on rx queue %d", rx_queue_id);
return -ret;
}
/**
* DPDK callback for rx queue interrupt disable.
* DPDK callback for Rx queue interrupt disable.
*
* @param dev
* Pointer to Ethernet device structure.
* @param rx_queue_id
* RX queue number.
* Rx queue number.
*
* @return
* 0 on success, negative on failure.
@ -1468,20 +1448,23 @@ mlx5_rx_intr_disable(struct rte_eth_dev *dev, uint16_t rx_queue_id)
struct priv *priv = mlx5_get_priv(dev);
struct rxq *rxq = (*priv->rxqs)[rx_queue_id];
struct rxq_ctrl *rxq_ctrl = container_of(rxq, struct rxq_ctrl, rxq);
struct ibv_cq *cq = rxq_ctrl->cq;
struct ibv_cq *ev_cq;
void *ev_ctx;
int ret = 0;
int ret;
ret = ibv_get_cq_event(cq->channel, &ev_cq, &ev_ctx);
if (ret || ev_cq != cq)
ret = -1;
else
ibv_ack_cq_events(cq, 1);
if (!rxq || !rxq_ctrl->channel) {
ret = EINVAL;
} else {
ret = ibv_get_cq_event(rxq_ctrl->cq->channel, &ev_cq, &ev_ctx);
if (ret || ev_cq != rxq_ctrl->cq)
ret = EINVAL;
}
if (ret)
WARN("unable to disable interrupt on rx queue %d",
rx_queue_id);
return ret;
else
ibv_ack_cq_events(rxq_ctrl->cq, 1);
return -ret;
}
#endif /* HAVE_UPDATE_CQ_CI */

View File

@ -307,10 +307,8 @@ int mlx5_rx_queue_setup(struct rte_eth_dev *, uint16_t, uint16_t, unsigned int,
const struct rte_eth_rxconf *, struct rte_mempool *);
void mlx5_rx_queue_release(void *);
uint16_t mlx5_rx_burst_secondary_setup(void *, struct rte_mbuf **, uint16_t);
int priv_intr_efd_enable(struct priv *priv);
void priv_intr_efd_disable(struct priv *priv);
int priv_create_intr_vec(struct priv *priv);
void priv_destroy_intr_vec(struct priv *priv);
int priv_rx_intr_vec_enable(struct priv *priv);
void priv_rx_intr_vec_disable(struct priv *priv);
#ifdef HAVE_UPDATE_CQ_CI
int mlx5_rx_intr_enable(struct rte_eth_dev *dev, uint16_t rx_queue_id);
int mlx5_rx_intr_disable(struct rte_eth_dev *dev, uint16_t rx_queue_id);

View File

@ -94,12 +94,13 @@ mlx5_dev_start(struct rte_eth_dev *dev)
(void *)priv, strerror(err));
goto error;
}
priv_dev_interrupt_handler_install(priv, dev);
if (dev->data->dev_conf.intr_conf.rxq) {
err = priv_intr_efd_enable(priv);
if (!err)
err = priv_create_intr_vec(priv);
err = priv_rx_intr_vec_enable(priv);
if (err) {
ERROR("%p: RX interrupt vector creation failed",
(void *)priv);
goto error;
}
priv_dev_interrupt_handler_install(priv, dev);
priv_xstats_init(priv);
priv_unlock(priv);
return 0;
@ -140,11 +141,8 @@ mlx5_dev_stop(struct rte_eth_dev *dev)
priv_destroy_hash_rxqs(priv);
priv_fdir_disable(priv);
priv_flow_stop(priv);
priv_rx_intr_vec_disable(priv);
priv_dev_interrupt_handler_uninstall(priv, dev);
if (priv->dev->data->dev_conf.intr_conf.rxq) {
priv_destroy_intr_vec(priv);
priv_intr_efd_disable(priv);
}
priv->started = 0;
priv_unlock(priv);
}