[dpdk-stable] [dpdk-dev] [PATCH v3 2/5] net/tap: fix mbuf and mem leak during queue release

[wangyunjian]

> -----Original Message-----
> From: Ferruh Yigit [mailto:ferruh.yigit at intel.com]
> Sent: Tuesday, April 7, 2020 8:55 PM
> To: wangyunjian <wangyunjian at huawei.com>; dev at dpdk.org
> Cc: keith.wiles at intel.com; Lilijun (Jerry) <jerry.lilijun at huawei.com>; xudingke
> <xudingke at huawei.com>; stable at dpdk.org
> Subject: Re: [dpdk-stable] [dpdk-dev] [PATCH v3 2/5] net/tap: fix mbuf and mem
> leak during queue release
> 
> On 4/7/2020 5:22 AM, wangyunjian wrote:
> > From: Yunjian Wang <wangyunjian at huawei.com>
> >
> > For the tap PMD, we should release mbufs and iovecs from the Rx queue
> > when close or remove device.
> >
> > Fixes: 0781f5762cfe ("net/tap: support segmented mbufs")
> > CC: stable at dpdk.org
> >
> > Signed-off-by: Yunjian Wang <wangyunjian at huawei.com>
> > ---
> >  drivers/net/tap/rte_eth_tap.c | 12 ++++++++++++
> >  1 file changed, 12 insertions(+)
> >
> > diff --git a/drivers/net/tap/rte_eth_tap.c
> > b/drivers/net/tap/rte_eth_tap.c index 4c4b6b0b2..a9ba0ca68 100644
> > --- a/drivers/net/tap/rte_eth_tap.c
> > +++ b/drivers/net/tap/rte_eth_tap.c
> > @@ -1022,6 +1022,7 @@ tap_dev_close(struct rte_eth_dev *dev)
> >  	int i;
> >  	struct pmd_internals *internals = dev->data->dev_private;
> >  	struct pmd_process_private *process_private = dev->process_private;
> > +	struct rx_queue *rxq;
> >
> >  	tap_link_set_down(dev);
> >  	tap_flow_flush(dev, NULL);
> > @@ -1029,8 +1030,13 @@ tap_dev_close(struct rte_eth_dev *dev)
> >
> >  	for (i = 0; i < RTE_PMD_TAP_MAX_QUEUES; i++) {
> >  		if (process_private->rxq_fds[i] != -1) {
> > +			rxq = &internals->rxq[i];
> >  			close(process_private->rxq_fds[i]);
> >  			process_private->rxq_fds[i] = -1;
> > +			rte_pktmbuf_free(rxq->pool);
> > +			rte_free(rxq->iovecs);
> > +			rxq->pool = NULL;
> > +			rxq->iovecs = NULL;
> >  		}
> >  		if (process_private->txq_fds[i] != -1) {
> >  			close(process_private->txq_fds[i]);
> > @@ -2399,6 +2405,7 @@ rte_pmd_tap_remove(struct rte_vdev_device
> *dev)
> >  	struct rte_eth_dev *eth_dev = NULL;
> >  	struct pmd_internals *internals;
> >  	struct pmd_process_private *process_private;
> > +	struct rx_queue *rxq;
> >  	int i;
> >
> >  	/* find the ethdev entry */
> > @@ -2425,8 +2432,13 @@ rte_pmd_tap_remove(struct rte_vdev_device
> *dev)
> >  	}
> >  	for (i = 0; i < RTE_PMD_TAP_MAX_QUEUES; i++) {
> >  		if (process_private->rxq_fds[i] != -1) {
> > +			rxq = &internals->rxq[i];
> >  			close(process_private->rxq_fds[i]);
> >  			process_private->rxq_fds[i] = -1;
> > +			rte_pktmbuf_free(rxq->pool);
> > +			rte_free(rxq->iovecs);
> > +			rxq->pool = NULL;
> > +			rxq->iovecs = NULL;
> >  		}
> >  		if (process_private->txq_fds[i] != -1) {
> >  			close(process_private->txq_fds[i]);
> >
> 
> Thanks for the fix, but instead of duplicating this for 'close()' & 'remove()', can
> 'remove()' call the 'close()'?
> They should be doing almost same thing but I can see there is difference
> between two, which may mean something is missed, unifying them fixes those
> missed parts too.
> Just a reminder that there can be tree valid path and should work fine:
> 1- user 'close()' the PMD
> 2- user directly 'remove()' the PMD
> 3- user first 'close()', later 'remove()' the PMD
> 
> Thanks,
> Ferruh

OK, I got your point, will do this in v4.

Thanks
Yunjian