[PATCH] net/failsafe: fix interrupt handle leak

[Ferruh Yigit]

On 8/29/2022 11:23 AM, David Marchand wrote:

> 
> On Fri, Apr 29, 2022 at 3:56 PM Ferruh Yigit <ferruh.yigit at xilinx.com> wrote:
>>
>> On 3/24/2022 3:09 PM, David Marchand wrote:
>>> A intr_handle is being allocated as a hack to get a (proxy) eventfd from
>>> the Linux interrupt implementation.
>>> But this handle is never freed.
>>>
>>> Remove this convoluted hack and create an eventfd in Linux case.
>>>
>>> Fixes: d61138d4f0e2 ("drivers: remove direct access to interrupt handle")
>>> Cc: stable at dpdk.org
>>>
>>> Signed-off-by: David Marchand <david.marchand at redhat.com>
>>> ---
>>>    drivers/net/failsafe/failsafe_ops.c | 32 ++++++++++-------------------
>>>    1 file changed, 11 insertions(+), 21 deletions(-)
>>>
>>> diff --git a/drivers/net/failsafe/failsafe_ops.c b/drivers/net/failsafe/failsafe_ops.c
>>> index 55e21d635c..2c23d0e70a 100644
>>> --- a/drivers/net/failsafe/failsafe_ops.c
>>> +++ b/drivers/net/failsafe/failsafe_ops.c
>>> @@ -6,6 +6,9 @@
>>>    #include <stdbool.h>
>>>    #include <stdint.h>
>>>    #include <unistd.h>
>>> +#ifdef RTE_EXEC_ENV_LINUX
>>> +#include <sys/eventfd.h>
>>> +#endif
>>>
>>>    #include <rte_debug.h>
>>>    #include <rte_atomic.h>
>>> @@ -387,28 +390,11 @@ fs_rx_queue_setup(struct rte_eth_dev *dev,
>>>                const struct rte_eth_rxconf *rx_conf,
>>>                struct rte_mempool *mb_pool)
>>>    {
>>> -     /*
>>> -      * FIXME: Add a proper interface in rte_eal_interrupts for
>>> -      * allocating eventfd as an interrupt vector.
>>> -      * For the time being, fake as if we are using MSIX interrupts,
>>> -      * this will cause rte_intr_efd_enable to allocate an eventfd for us.
>>> -      */
>>> -     struct rte_intr_handle *intr_handle;
>>>        struct sub_device *sdev;
>>>        struct rxq *rxq;
>>>        uint8_t i;
>>>        int ret;
>>>
>>> -     intr_handle = rte_intr_instance_alloc(RTE_INTR_INSTANCE_F_PRIVATE);
>>> -     if (intr_handle == NULL)
>>> -             return -ENOMEM;
>>> -
>>> -     if (rte_intr_type_set(intr_handle, RTE_INTR_HANDLE_VFIO_MSIX))
>>> -             return -rte_errno;
>>> -
>>> -     if (rte_intr_efds_index_set(intr_handle, 0, -1))
>>> -             return -rte_errno;
>>> -
>>>        fs_lock(dev, 0);
>>>        if (rx_conf->rx_deferred_start) {
>>>                FOREACH_SUBDEV_STATE(sdev, i, dev, DEV_PROBED) {
>>> @@ -442,12 +428,16 @@ fs_rx_queue_setup(struct rte_eth_dev *dev,
>>>        rxq->info.nb_desc = nb_rx_desc;
>>>        rxq->priv = PRIV(dev);
>>>        rxq->sdev = PRIV(dev)->subs;
>>> -     ret = rte_intr_efd_enable(intr_handle, 1);
>>> -     if (ret < 0) {
>>> +#ifdef RTE_EXEC_ENV_LINUX
>>> +     rxq->event_fd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
>>> +     if (rxq->event_fd < 0) {
>>> +             ERROR("Failed to create an eventfd: %s", strerror(errno));
>>>                fs_unlock(dev, 0);
>>> -             return ret;
>>> +             return -errno;
>>>        }
>>> -     rxq->event_fd = rte_intr_efds_index_get(intr_handle, 0);
>>> +#else
>>> +     rxq->event_fd = -1;
>>> +#endif
>>
>> How this impacts the BSD? I don't know if driver used on BSD but
>> technically it looks supported.
>>
>> @Gaetan, any objection to the change?
> 
> There was no feedback for months, can we get this merged?
> Thanks.
> 

There is no comment from maintainer, but patch is out for a while, so 
agree to proceed:

Acked-by: Ferruh Yigit <ferruh.yigit at xilinx.com>

Applied to dpdk-next-net/main, thanks.