Per Phase 4 plan PR #14 + kerneldoc audit (Task #19). Six call sites
deferred per-RX-frame mac80211 dispatch via tasklet; replace with the
synchronous-from-process-context API ieee80211_rx_ni() which does its
own local_bh_disable wrap.
Why _ni and not _list:
Phase 4 plan originally targeted ieee80211_rx_list for batch
delivery. Mining mt76 mainline (the only driver using _list)
showed the canonical pattern requires threading a struct list_head
through the per-frame call chain. bes2600s WSM dispatcher
(wsm_handle_rx -> bes2600_rx_cb / wsm.c beacon path) sits between
the bh threads SDIO read and the mac80211 hand-off; threading a
list_head through the dispatcher is a non-trivial refactor.
ieee80211_rx_ni() is the simpler drop-in: no list management, still
removes the tasklet hop. Per-call local_bh_disable cost is trivial
vs the saved tasklet schedule. Future refactor can revisit _list
if measurements warrant.
Sites converted:
- ap.c:96 (bes2600_sta_add link-id rx_queue drain on AP-mode
STA add). Was inside spin_lock_bh(&ps_state_lock);
refactored to splice the queue under the lock then
deliver after unlock — _ni runs the synchronous
mac80211 RX path inline, would otherwise hold the
lock across mac80211 dispatch. splice via
skb_queue_splice_init into a local sk_buff_head.
- sta.c:1487 (deauth-frame inject in inactivity-event handler).
Not under any lock; direct conversion.
- txrx.c:1960 (early-data + pm_unsupported branch from Patch E).
- txrx.c:1967 (early-data + LINK_SOFT-not-set branch).
- txrx.c:1971 (normal RX path in bes2600_rx_cb).
- wsm.c:2415 (beacon delivery in scan-complete WSM handler).
beacon SKB ownership is preserved by the existing
skb_copy(beacon, GFP_ATOMIC) -> beacon_bkp pattern;
no lifecycle change needed.
Mixing constraint (kerneldoc include/net/mac80211.h:5399-5430):
ieee80211_rx_ni() cannot mix with ieee80211_rx_irqsafe() for a
single hardware. All 6 sites convert atomically; no mixed state.
Build verified clean on ohm sandbox: srcversion 619A51E61BF5479AAC146E6.
Predicted Phase 7 delta: +5-15% over v3+D+E baseline (2.35 MB/s mean
on v3 alone; D+E single-rep was 3.22 MB/s). Modest improvement
expected from removing the tasklet schedule per RX frame. Smaller
deltas would still be a net win for upstream-cleanliness — the
kernel.org submission story benefits from not using _irqsafe from
process context.
The bes2600 driver is a fork of the upstream cw1200 driver
(drivers/net/wireless/st/cw1200/, ST-Ericsson, Dmitry Tarnyagin
2010-2011). The fork's file headers have three GPL-compliance issues:
1. NO SPDX-License-Identifier on any of 48 source files (cw1200
mainline has them on all 25). kernel.org-mandated since 2017.
2. Original "Copyright (c) 2010, ST-Ericsson" lines stripped from
all files inherited from cw1200, replaced with
"Copyright (c) 2010, Bestechnic" — factually impossible
(Bestechnic did not author the 2010 work) and a GPL-2.0 §1
attribution-preservation violation.
3. The "GPL version 2 as published by the Free Software Foundation"
boilerplate paragraph is redundant alongside SPDX and is the
legacy form modern kernel sources have replaced.
This patch corrects all three for the 48 .c/.h files in bes2600/:
- Adds `// SPDX-License-Identifier: GPL-2.0-only` (or `/* ... */`
for headers) as line 1 of every file.
- Restores `Copyright (c) 2010, ST-Ericsson` + `Author: Dmitry
Tarnyagin <dmitry.tarnyagin@lockless.no>` as the FIRST copyright
chain entry on all 22 files derived from cw1200 (bh.{c,h},
debug.{c,h}, fwio.{c,h}, hwio.{c,h}, main.c, pm.{c,h},
queue.{c,h}, scan.{c,h}, sta.{c,h}, txrx.{c,h}, wsm.{c,h}).
- Keeps `Copyright (c) 2022, Bestechnic (Beijing) Co., Ltd.` as
the SECOND chain entry where Bestechnic genuinely contributed.
- Notes "Derived from cw1200_sdio.c" + ST-Ericsson copyright on
bes2600_sdio.c (heavy derivation, not a literal rename).
- Notes "Replaces hwbus.h from cw1200/" + ST-Ericsson copyright
on sbus.h.
- Preserves the prism54/islsm authorship chain on main.c and
bes2600.h (Michael Wu 2006 + Jean-Baptiste Note 2004-2006).
- Drops the GPL-2.0 boilerplate paragraph in favour of SPDX.
No code changes — only file-header comment blocks. Module build is
unaffected (verified by header-only diff scope).
This is a prerequisite for any kernel.org submission attempt. The
existing MODULE_LICENSE("GPL") + MODULE_AUTHOR(Tarnyagin@stericsson.com)
declarations were already present and are unchanged here; the
mismatch between MODULE_AUTHOR and the (since-corrected) per-file
copyrights is now resolved.
test0r
Julian