[dpdk-dev] [PATCH v4 1/2] net/tap: change queue fd to be pointers to process private
Ferruh Yigit
ferruh.yigit at intel.com
Wed Oct 3 19:59:09 CEST 2018
On 10/2/2018 11:34 AM, Raslan Darawsheh wrote:
> change the fds for the queues to be pointers and add new process private
> structure and make the queue fds point to it.
>
> Signed-off-by: Raslan Darawsheh <rasland at mellanox.com>
> ---
> drivers/net/tap/rte_eth_tap.c | 63 ++++++++++++++++++++++++-------------------
> drivers/net/tap/rte_eth_tap.h | 9 +++++--
> drivers/net/tap/tap_intr.c | 4 +--
> 3 files changed, 44 insertions(+), 32 deletions(-)
>
> diff --git a/drivers/net/tap/rte_eth_tap.c b/drivers/net/tap/rte_eth_tap.c
> index ad5ae98..8cc4552 100644
> --- a/drivers/net/tap/rte_eth_tap.c
> +++ b/drivers/net/tap/rte_eth_tap.c
> @@ -64,6 +64,7 @@
>
> static struct rte_vdev_driver pmd_tap_drv;
> static struct rte_vdev_driver pmd_tun_drv;
> +static struct pmd_process_private *process_private;
This is the handlers for eth_dev queues, this should be _per eth_dev_, you can't
have a single global variable for this, we will see the problems below.
<...>
> @@ -1633,6 +1634,10 @@ eth_dev_tap_create(struct rte_vdev_device *vdev, char *tap_name,
> goto error_exit_nodev;
> }
>
> + process_private = (struct pmd_process_private *)
> + rte_zmalloc_socket(tap_name, sizeof(struct pmd_process_private),
> + RTE_CACHE_LINE_SIZE, dev->device->numa_node);
For each tap device, you overwrite the "process_private",
- So it has the address of last created tap device, we will come back this one
- and problem is how to free this back if an eth_dev removed? We lost references
except last one.
> +
> pmd = dev->data->dev_private;
> pmd->dev = dev;
> snprintf(pmd->name, sizeof(pmd->name), "%s", tap_name);
> @@ -1669,8 +1674,10 @@ eth_dev_tap_create(struct rte_vdev_device *vdev, char *tap_name,
> /* Presetup the fds to -1 as being not valid */
> pmd->ka_fd = -1;
> for (i = 0; i < RTE_PMD_TAP_MAX_QUEUES; i++) {
> - pmd->rxq[i].fd = -1;
> - pmd->txq[i].fd = -1;
> + process_private->rxq_fds[i] = -1;
> + process_private->txq_fds[i] = -1;
> + pmd->rxq[i].fd = &process_private->rxq_fds[i];
> + pmd->txq[i].fd = &process_private->txq_fds[i];
for eth_dev, dev->data->dev_private->rxq[i].fd points to a memory address,
and remember "dev->data->dev_private" is shared between primary and secondary,
when secondary updates its rxq[i].fd to point its memory block, won't it corrupt
the primary???
I think redirection is not helping here, I am not sure to the this within the
shared memory, you need a not shared area.
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