softbkl: replace hardware k0lock with software ticket lock (SOFT_BKL)#77
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Erich Plondke (eplondke) wants to merge 1 commit into
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softbkl: replace hardware k0lock with software ticket lock (SOFT_BKL)#77Erich Plondke (eplondke) wants to merge 1 commit into
Erich Plondke (eplondke) wants to merge 1 commit into
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Introduce SOFT_BKL compile-time flag that redirects all BKL lock/unlock
sites from the hardware k0lock instruction to an in-memory ticket spinlock.
- BKL_LOCK/BKL_UNLOCK macros in hw.h dispatch to H2K_spinlock_{lock,unlock}
when SOFT_BKL is set, k0lock/k0unlock otherwise
- ASM_BKL_LOCK/ASM_BKL_UNLOCK macros in asm_std.h wrap the LL/SC ticket lock
for .S files; K0LOCK/K0UNLOCK (bypass poison) otherwise
- Makefile poisons bare k0lock/k0unlock in .S files to enforce macro use
- H2K_spinlock_t bkl field added to H2K_kg_t under SOFT_BKL
- All 20 .S files converted from bare k0lock/k0unlock to ASM_BKL_LOCK/UNLOCK
- ticket lock: 32-bit packed (upper 16 = next, lower 16 = now_serving),
strictly fair FIFO, removes dccleana from acquire path
- h2_init() sets H2K_gp (r28) so INC_KERNEL tests work without per-test change
- boot.ref.S adds call 1f to establish r31 before first ASM_BKL_LOCK
make testall SOFT_BKL=1: 1224 passed, 0 failed
Signed-off-by: Erich Plondke <erich@qti.qualcomm.com>
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July 13, 2026 18:20
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Introduce SOFT_BKL compile-time flag that redirects all BKL lock/unlock sites from the hardware k0lock instruction to an in-memory ticket spinlock.
make testall SOFT_BKL=1: 1224 passed, 0 failed