This series lets a dpaa2 worker sleep on a queue's data-availability
notification instead of busy-polling, exposed through the generic
rte_eth_dev_rx_intr_* API (NAPI-style: poll while frames keep coming,
arm the interrupt and sleep when the queue runs dry).
Why it is not a trivial .rx_queue_intr_enable
----------------------------------------------
A worker wakes on its software portal's DQRI, which fires when the
portal's DQRR holds frames. The default dpaa2 Rx burst pulls frames
from the FQ with a volatile dequeue and cannot be interrupt-driven; to
wake on the DQRI the FQ must instead be pushed to the portal's DQRR.
The natural dpni_set_queue with a notification destination would have to
target the worker's portal, but that portal is only known once a worker
affines, after dev_start, and that MC command holds the global MC lock
long enough to wedge the firmware while traffic runs. So the bind cannot
be done late, against the polling lcore.
Design
------
Each Rx FQ is bound to its own DPCON channel, statically, at dev_start
while the dpni is still disabled (no knowledge of the polling lcore). A
worker later subscribes its own ethrx portal to the channel and arms the
DQRI in rx_queue_intr_enable, a one-shot per-portal op, never the wedging
set_queue. One portal serves every queue a worker owns, so the DQRR
burst demuxes frames to their FQ by fqd_ctx; foreign frames are parked in
the target queue's stash, so the application polls all its queues after a
wakeup, the same scheduling contract as plain DPDK polling. A queue can
be re-homed to another lcore at runtime with no set_queue and no port
stop.
This reuses the event PMD's pushed/DQRR model but with one DPCON per FQ
and static affinity (no QBMan scheduling), so the DPCON allocator is
moved from the event driver to the fslmc bus and shared.
Patches 1 and 2 move the DPCON allocator to the fslmc bus and make the
portal DQRI epoll optional; patch 3 adds the interrupt support proper and
patch 4 tunes the DQRI coalescing holdoff. Patch 5 (rx_queue_count NULL on
the primary process) is a real fix the path depends on and uncovered,
tagged for stable and backportable on its own. Patch 6 (drop the software
VLAN strip) is an independent net/dpaa2 change the interrupt path does not
require.
The path also depends on two fixes sent separately: an eal change so the
shared portal eventfd does not fail with -EEXIST (already applied to main)
and the ethdev fix for fast-path ops left NULL after port stop (see
Depends-on below).
Tested on LX2160A (lx2160acex7).
Depends-on: series-38450 ("ethdev: fix fast-path ops on a stopped port")
v2:
- Dropped the RSS RETA patch, an independent net/dpaa2 change the
interrupt path does not require; it will be sent as its own series.
- Dropped the ethdev fast-path ops fix; it is now a standalone series
(Depends-on above).
- Dropped the eal/interrupts -EEXIST fix, applied to main by David Marchand.
- Declared qbman_swp_interrupt_set_inhibit and qbman_swp_dqrr_size
__rte_internal (David Marchand).
- Minor formatting cleanup in the Rx interrupt setup.
Maxime Leroy (6):
bus/fslmc: move DPCON management from event driver to bus
bus/fslmc/dpio: make the portal DQRI epoll optional
net/dpaa2: support Rx queue interrupts
bus/fslmc/dpio: tune DQRI interrupt coalescing holdoff
net/dpaa2: fix Rx queue count for primary process
net/dpaa2: drop the fake software VLAN strip offload
doc/guides/nics/dpaa2.rst | 10 +
doc/guides/nics/features/dpaa2.ini | 1 +
doc/guides/rel_notes/release_26_07.rst | 7 +
drivers/bus/fslmc/meson.build | 1 +
.../fslmc/portal}/dpaa2_hw_dpcon.c | 16 +-
drivers/bus/fslmc/portal/dpaa2_hw_dpio.c | 113 ++++--
drivers/bus/fslmc/portal/dpaa2_hw_dpio.h | 12 +
drivers/bus/fslmc/portal/dpaa2_hw_pvt.h | 35 +-
.../fslmc/qbman/include/fsl_qbman_portal.h | 11 +
drivers/bus/fslmc/qbman/qbman_portal.c | 7 +
drivers/event/dpaa2/dpaa2_eventdev.h | 5 +-
drivers/event/dpaa2/meson.build | 1 -
drivers/net/dpaa2/dpaa2_ethdev.c | 349 +++++++++++++++++-
drivers/net/dpaa2/dpaa2_ethdev.h | 10 +
drivers/net/dpaa2/dpaa2_rxtx.c | 123 +++++-
15 files changed, 647 insertions(+), 54 deletions(-)
rename drivers/{event/dpaa2 => bus/fslmc/portal}/dpaa2_hw_dpcon.c (90%)
--
2.43.0
