On Tue, 20 Feb 2024 03:29:04 +0000 bugzi...@dpdk.org wrote: > https://bugs.dpdk.org/show_bug.cgi?id=1381 > > Bug ID: 1381 > Summary: TAP device can not support 17 queues > Product: DPDK > Version: 23.11 > Hardware: All > OS: All > Status: UNCONFIRMED > Severity: normal > Priority: Normal > Component: ethdev > Assignee: dev@dpdk.org > Reporter: step...@networkplumber.org > Target Milestone: --- > > If you try: > # dpdk-testpmd --log-level=pmd.net.tap:debug -l 1-2 --vdev=net_tap0 -- -i > --rxq=8 --txq=8 > > It will fail because: > EAL: Detected CPU lcores: 8 > EAL: Detected NUMA nodes: 1 > EAL: Detected static linkage of DPDK > EAL: Multi-process socket /var/run/dpdk/rte/mp_socket > EAL: Selected IOVA mode 'VA' > rte_pmd_tap_probe(): Initializing pmd_tap for net_tap0 > eth_dev_tap_create(): TAP device on numa 0 > tun_alloc(): /dev/net/tun Features 00007173 > tun_alloc(): Multi-queue support for 16 queues > tun_alloc(): Device name is 'dtap0' > tun_alloc(): Using rt-signal 35 > eth_dev_tap_create(): allocated dtap0 > Interactive-mode selected > testpmd: create a new mbuf pool <mb_pool_0>: n=155456, size=2176, socket=0 > testpmd: preferred mempool ops selected: ring_mp_mc > > Warning! port-topology=paired and odd forward ports number, the last port will > pair with itself. > > Configuring Port 0 (socket 0) > tap_dev_configure(): net_tap0: dtap0: TX configured queues number: 8 > tap_dev_configure(): net_tap0: dtap0: RX configured queues number: 8 > tun_alloc(): /dev/net/tun Features 00007173 > tun_alloc(): Multi-queue support for 16 queues > tun_alloc(): Device name is 'dtap0' > tap_setup_queue(): dtap0: add tx queue for qid 0 fd 26 > tap_tx_queue_setup(): TX TUNTAP device name dtap0, qid 0 on fd 26 csum off > tun_alloc(): /dev/net/tun Features 00007173 > tun_alloc(): Multi-queue support for 16 queues > tun_alloc(): Device name is 'dtap0' > tap_setup_queue(): dtap0: add tx queue for qid 1 fd 212 > tap_tx_queue_setup(): TX TUNTAP device name dtap0, qid 1 on fd 212 csum off > tun_alloc(): /dev/net/tun Features 00007173 > tun_alloc(): Multi-queue support for 16 queues > tun_alloc(): Device name is 'dtap0' > tap_setup_queue(): dtap0: add tx queue for qid 2 fd 213 > tap_tx_queue_setup(): TX TUNTAP device name dtap0, qid 2 on fd 213 csum off > tun_alloc(): /dev/net/tun Features 00007173 > tun_alloc(): Multi-queue support for 16 queues > tun_alloc(): Device name is 'dtap0' > tap_setup_queue(): dtap0: add tx queue for qid 3 fd 214 > tap_tx_queue_setup(): TX TUNTAP device name dtap0, qid 3 on fd 214 csum off > tun_alloc(): /dev/net/tun Features 00007173 > tun_alloc(): Multi-queue support for 16 queues > tun_alloc(): Device name is 'dtap0' > tap_setup_queue(): dtap0: add tx queue for qid 4 fd 215 > tap_tx_queue_setup(): TX TUNTAP device name dtap0, qid 4 on fd 215 csum off > tun_alloc(): /dev/net/tun Features 00007173 > tun_alloc(): Multi-queue support for 16 queues > tun_alloc(): Device name is 'dtap0' > tap_setup_queue(): dtap0: add tx queue for qid 5 fd 216 > tap_tx_queue_setup(): TX TUNTAP device name dtap0, qid 5 on fd 216 csum off > tun_alloc(): /dev/net/tun Features 00007173 > tun_alloc(): Multi-queue support for 16 queues > tun_alloc(): Device name is 'dtap0' > tap_setup_queue(): dtap0: add tx queue for qid 6 fd 217 > tap_tx_queue_setup(): TX TUNTAP device name dtap0, qid 6 on fd 217 csum off > tun_alloc(): /dev/net/tun Features 00007173 > tun_alloc(): Multi-queue support for 16 queues > tun_alloc(): Device name is 'dtap0' > tap_setup_queue(): dtap0: add tx queue for qid 7 fd 218 > tap_tx_queue_setup(): TX TUNTAP device name dtap0, qid 7 on fd 218 csum off > tap_setup_queue(): dtap0: dup fd 26 for rx queue qid 0 (219) > tap_rx_queue_setup(): RX TUNTAP device name dtap0, qid 0 on fd 219 > tap_setup_queue(): dtap0: dup fd 212 for rx queue qid 1 (220) > tap_rx_queue_setup(): RX TUNTAP device name dtap0, qid 1 on fd 220 > tap_setup_queue(): dtap0: dup fd 213 for rx queue qid 2 (221) > tap_rx_queue_setup(): RX TUNTAP device name dtap0, qid 2 on fd 221 > tap_setup_queue(): dtap0: dup fd 214 for rx queue qid 3 (222) > tap_rx_queue_setup(): RX TUNTAP device name dtap0, qid 3 on fd 222 > tap_setup_queue(): dtap0: dup fd 215 for rx queue qid 4 (223) > tap_rx_queue_setup(): RX TUNTAP device name dtap0, qid 4 on fd 223 > tap_setup_queue(): dtap0: dup fd 216 for rx queue qid 5 (224) > tap_rx_queue_setup(): RX TUNTAP device name dtap0, qid 5 on fd 224 > tap_setup_queue(): dtap0: dup fd 217 for rx queue qid 6 (225) > tap_rx_queue_setup(): RX TUNTAP device name dtap0, qid 6 on fd 225 > tap_setup_queue(): dtap0: dup fd 218 for rx queue qid 7 (226) > tap_rx_queue_setup(): RX TUNTAP device name dtap0, qid 7 on fd 226 > EAL: Cannot send more than 8 FDs > tap_mp_req_on_rxtx(): Failed to send start req to secondary 7 > > This is a regression caused by: > commit c36ce7099c2187926cd62cff7ebd479823554929 > Author: Kumara Parameshwaran <kumaraparames...@gmail.com> > Date: Mon Jan 31 20:02:34 2022 +0530 > > net/tap: fix to populate FDs in secondary process > > When a tap device is hotplugged to primary process which in turn > adds the device to all secondary process, the secondary process > does a tap_mp_attach_queues, but the fds are not populated in > the primary during the probe they are populated during the queue_setup, > added a fix to sync the queues during rte_eth_dev_start > > Fixes: 4852aa8f6e21 ("drivers/net: enable hotplug on secondary process") > Cc: sta...@dpdk.org > > Signed-off-by: Kumara Parameshwaran <kparamesh...@vmware.com> > Reviewed-by: Ferruh Yigit <ferruh.yi...@intel.com> >
The number of file descriptors allowed in rte_mp_msg should be much larger. The Linux kernel has an upper limit SCM_MAX_FD which is 253 (see net/scm.h) But fixing this will break ABI because rte_mp_msg structure was exposed in rte_eal.h. It should have been internal! Alternatively, since fds[] is the last field in rte_mp_msg, and num_fds is also there, fds[] could have been a flexible array, rather than hard coded.
