sched/cache: Keep nr_pref_llc_running in the runnable domain, to fix LLC mis-scheduling buggrafted

alb_break_llc() decides whether to break LLC preference during active
load balance. It does so by testing that every runnable fair task on the
source rq prefers its LLC:

	env->src_rq->nr_pref_llc_running == env->src_rq->cfs.h_nr_runnable

But the two counters cover different sets. nr_pref_llc_running is updated
in account_llc_enqueue()/account_llc_dequeue(), next to cfs_rq->nr_queued,
so it follows queued tasks. h_nr_runnable is updated in set_delayed()/
clear_delayed() and drops delay-dequeued tasks.

So under DELAY_DEQUEUE, a preferring task that goes to sleep stays counted
in nr_pref_llc_running while h_nr_runnable falls. The equality then breaks,
alb_break_llc() returns false, and active balance is free to pull a task
off its preferred LLC. Active balance only moves runnable tasks, and this
is the only LLC check it consults: once the stopper runs, LBF_ACTIVE_LB
skips the per-task test in can_migrate_task(). The runnable set is the one
we want.

Fix it on the counter side. A task should be counted in
nr_pref_llc_running exactly while it is both queued on its preferred LLC
(pref_llc_queued) and runnable (!sched_delayed). Define that membership
once in task_pref_llc_runnable(), and adjust the counter only through
pref_llc_running_inc()/pref_llc_running_dec() from the four sites that
change either input: account_llc_enqueue(), account_llc_dequeue(),
set_delayed() and clear_delayed(). Gating every update on the same
predicate keeps the delay, wake and dequeue paths from double-counting
or underflowing; see the comments at those sites for the ordering.

nr_llc_running and sd->llc_counts are not touched and stay on queued
semantics.

Fixes: 714059f79ff0 ("sched/cache: Handle moving single tasks to/from their preferred LLC")
Closes: https://lore.kernel.org/lkml/20260827135000.735138-1-zhanxusheng@xiaomi.com/
Reported-by: Zhan Xusheng <zhanxusheng@xiaomi.com>
Suggested-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Kayra Cizmeci <kayracizmeci@gmail.com>
Cc: <stable@kernel.org> # v7.2.x
Link: https://patch.msgid.link/06af61afedac32e6477f57feb4d658f6c411c3af.1790035273.git.tim.c.chen@linux.intel.com

1 files changed, 202 insertions, 0 deletions

diff --git a/sound/firewire/Kconfig b/sound/firewire/Kconfig
new file mode 100644
index 000000000..5973c25c2
--- /dev/null
+++ b/sound/firewire/Kconfig
@@ -0,0 +1,202 @@
+# SPDX-License-Identifier: GPL-2.0-only
+menuconfig SND_FIREWIRE
+	bool "FireWire sound devices"
+	depends on FIREWIRE
+	default y
+	help
+	  Support for IEEE-1394/FireWire/iLink sound devices.
+
+if SND_FIREWIRE && FIREWIRE
+
+config SND_FIREWIRE_LIB
+	tristate
+	select SND_PCM
+	select SND_RAWMIDI
+
+config SND_DICE
+	tristate "DICE-based DACs support"
+	select SND_HWDEP
+	select SND_FIREWIRE_LIB
+	help
+	  Say Y here to include support for devices based on the DICE chip family
+	  (DICE-II/TCD2210(Mini)/TCD2220(Jr.)) which TC Applied Technologies (TCAT) produced.
+	   * Allen and Heath Zed R16
+	   * Alesis iO 14/26 FireWire, MasterControl, MultiMix 8/12/16 FireWire
+	   * Avid Mbox 3 Pro
+	   * FlexRadio Systems FLEX-3000, FLEX-5000
+	   * Focusrite Liquid Saffire 56
+	   * Focusrite Saffire Pro 14, Pro 24, Pro 24 DSP, Pro 26, Pro 40(TCD2220)
+	   * Harman Music Group Lexicon I-ONIX FW810S
+	   * Loud Technologies Mackie Onyx Blackbird, Onyx 820i/1220i/1620i/1640i (latter models)
+	   * M-Audio ProFire 610/2626
+	   * Mytek Stereo192-DSD DAC
+	   * Midas Klark Teknik VeniceF series
+	   * PreSonus FireStudio, FireStudio Mobile, FireStudio Project, FireStudio Tube
+	   * PreSonus StudioLive 16.4.2, 16.0.2, 24.4.2, 32.4.2
+	   * Solid State Logic Duende Classic, Duende Mini
+	   * TC Electronic Studio Konnekt 48, Konnekt 24D, Konnekt Live, Impact Twin
+	   * TC Electronic Digital Konnekt x32, Desktop Konnekt 6
+	   * Weiss Engineering ADC2, Vesta, Minerva, AFI1, DAC1, INT202, DAC202
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called snd-dice.
+
+config SND_OXFW
+	tristate "Oxford Semiconductor FW970/971 chipset support"
+	select SND_FIREWIRE_LIB
+	select SND_HWDEP
+	help
+	  Say Y here to include support for FireWire devices based on
+	  Oxford Semiconductor FW970/971 chipset.
+	   * Griffin Firewave
+	   * LaCie Firewire Speakers
+	   * Behringer F-Control Audio 202
+	   * Mackie(Loud) Onyx-i series (former models)
+	   * Mackie(Loud) Onyx 1640i (former model)
+	   * Mackie(Loud) Onyx Satellite
+	   * Mackie(Loud) Tapco Link.Firewire
+	   * Mackie(Loud) d.2 pro/d.4 pro (built-in FireWire card with OXFW971 ASIC)
+	   * Mackie(Loud) U.420/U.420d
+	   * TASCAM FireOne
+	   * Stanton Controllers & Systems 1 Deck/Mixer
+	   * APOGEE duet FireWire
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called snd-oxfw.
+
+config SND_ISIGHT
+	tristate "Apple iSight microphone"
+	select SND_FIREWIRE_LIB
+	help
+	  Say Y here to include support for the front and rear microphones
+	  of the Apple iSight web camera.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called snd-isight.
+
+config SND_FIREWORKS
+	tristate "Echo Fireworks board module support"
+	select SND_FIREWIRE_LIB
+	select SND_HWDEP
+	help
+	  Say Y here to include support for FireWire devices based
+	  on Echo Digital Audio Fireworks board:
+	   * Mackie Onyx 400F/1200F
+	   * Echo AudioFire12/8(until 2009 July)
+	   * Echo AudioFire2/4/Pre8/8(since 2009 July)
+	   * Echo Fireworks 8/HDMI
+	   * Gibson Robot Interface Pack/GoldTop
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called snd-fireworks.
+
+config SND_BEBOB
+	tristate "BridgeCo DM1000/DM1100/DM1500 with BeBoB firmware"
+	select SND_FIREWIRE_LIB
+	select SND_HWDEP
+	help
+	 Say Y here to include support for FireWire devices based
+	 on BridgeCo DM1000/DM1100/DM1500 with BeBoB firmware:
+	  * Edirol FA-66/FA-101
+	  * PreSonus FIREBOX/FIREPOD/FP10/Inspire1394
+	  * BridgeCo RDAudio1/Audio5
+	  * Mackie Onyx 1220/1620/1640 (FireWire I/O Card)
+	  * Mackie d.2 (optional FireWire card with DM1000 ASIC)
+	  * Stanton FinalScratch 2 (ScratchAmp)
+	  * Tascam IF-FW/DM
+	  * Behringer XENIX UFX 1204/1604
+	  * Behringer Digital Mixer X32 series (X-UF Card)
+	  * Behringer FCA610/1616
+	  * Apogee Rosetta 200/400 (X-FireWire card)
+	  * Apogee DA/AD/DD-16X (X-FireWire card)
+	  * Apogee Ensemble
+	  * ESI QuataFire 610
+	  * AcousticReality eARMasterOne
+	  * CME MatrixKFW
+	  * Phonic Helix Board 12 MkII/18 MkII/24 MkII
+	  * Phonic Helix Board 12 Universal/18 Universal/24 Universal
+	  * Lynx Aurora 8/16 (LT-FW)
+	  * ICON FireXon
+	  * PrismSound Orpheus/ADA-8XR
+	  * TerraTec PHASE 24 FW/PHASE X24 FW/PHASE 88 Rack FW
+	  * TerraTec EWS MIC2/EWS MIC8
+	  * TerraTec Aureon 7.1 FireWire
+	  * Yamaha GO44/GO46
+	  * Focusrite Saffire/Saffire LE/SaffirePro10 IO/SaffirePro26 IO
+	  * M-Audio FireWire410/AudioPhile/Solo
+	  * M-Audio Ozonic/NRV10/ProfireLightBridge
+	  * M-Audio FireWire 1814/ProjectMix IO
+	  * Digidesign Mbox 2 Pro
+	  * ToneWeal FW66
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called snd-bebob.
+
+config SND_FIREWIRE_DIGI00X
+	tristate "Digidesign Digi 002/003 family support"
+	select SND_FIREWIRE_LIB
+	select SND_HWDEP
+	help
+	 Say Y here to include support for Digidesign Digi 002/003 family.
+	  * Digi 002 Console
+	  * Digi 002 Rack
+	  * Digi 003 Console
+	  * Digi 003 Rack
+	  * Digi 003 Rack+
+
+	 To compile this driver as a module, choose M here: the module
+	 will be called snd-firewire-digi00x.
+
+config SND_FIREWIRE_TASCAM
+	tristate "TASCAM FireWire series support"
+	select SND_FIREWIRE_LIB
+	select SND_HWDEP
+	help
+	 Say Y here to include support for TASCAM.
+	  * FW-1884
+	  * FW-1082
+	  * FW-1804
+
+	 To compile this driver as a module, choose M here: the module
+	 will be called snd-firewire-tascam.
+
+config SND_FIREWIRE_MOTU
+	tristate "Mark of the unicorn FireWire series support"
+	select SND_FIREWIRE_LIB
+	select SND_HWDEP
+	help
+	 Say Y here to enable support for FireWire devices which MOTU produced:
+	  * 828
+	  * 896
+	  * 828mk2
+	  * 896hd
+	  * Traveler
+	  * Ultralite
+	  * 8pre
+	  * 828mk3 (FireWire only)
+	  * 828mk3 (Hybrid)
+	  * 896mk3 (FireWire only)
+	  * 896mk3 (Hybrid)
+	  * Ultralite mk3 (FireWire only)
+	  * Ultralite mk3 (Hybrid)
+	  * Traveler mk3
+	  * Audio Express
+	  * Track 16
+	  * 4pre
+
+	 To compile this driver as a module, choose M here: the module
+	 will be called snd-firewire-motu.
+
+config SND_FIREFACE
+	tristate "RME Fireface series support"
+	select SND_FIREWIRE_LIB
+	select SND_HWDEP
+	help
+	 Say Y here to include support for RME fireface series.
+	  * Fireface 400
+	  * Fireface 800
+	  * Fireface UFX
+	  * Fireface UCX
+	  * Fireface 802
+
+endif # SND_FIREWIRE