Commit Graph

2 Commits

Author SHA1 Message Date
MechaCat02
27d3608174 fix(kernel): KRNBUG-D08 — wall-clock v-sync under --parallel
The synthetic v-sync ticker used a per-instruction proxy
(VSYNC_INSTR_PERIOD = 150 k) tuned for ~10 MIPS lockstep
throughput → 60 Hz. Audit M11 observed this drifts under
`--parallel`: with 6 worker threads sharing the kernel mutex,
the dispatcher executes more PPC instructions per tick
callback, so the accumulator never crosses 150 k. Result:
~629 v-syncs/100M lockstep → ~2 v-syncs/100M --parallel.

Hybrid solution preserves lockstep determinism (which the
goldens depend on) while fixing --parallel:

* `tick_vsync_instr(instr_count)` — legacy instruction-count
  ticker, used by lockstep. Bit-stable across runs.

* `tick_vsync_wallclock()` — new Instant-based ticker. Fires
  `floor(elapsed / VSYNC_PERIOD)` v-syncs since the anchor
  and advances the anchor by that many full periods (no
  lazy backlog). Capped at INTERRUPT_QUEUE_CAP per call so a
  forward-jumping clock can't overflow the FIFO.

* `KernelState.parallel_active` flag set at startup from
  `--parallel` / `XENIA_PARALLEL=1`. Read by `coord_pre_round`
  in main.rs to choose between the two tickers.

Verification:

* cargo test --workspace --release: 561 passing (+3 new
  wall-clock tests vs prior 558 baseline).
* lockstep -n 100M --stable-digest: BIT-IDENTICAL to
  pre-Phase-3 baseline. interrupts_delivered preserved at
  ~630 (was ~629 pre-fix).
* --parallel --reservations-table -n 30M: interrupts_delivered
  rose from ~2 to 17. (FIFO INTERRUPT_QUEUE_CAP=4 still caps
  burst delivery; that's a separate bottleneck — addressed
  by raising cap when --parallel queue depth becomes the
  next blocker.)

Trade-off: --parallel runs are non-deterministic at the
v-sync rate by design (per audit M05 PPCBUG-703 already).
Lockstep stays bit-identical, so the `sylpheed_n*m.json`
goldens are untouched.

Audit IDs: KRNBUG-D08 (closed).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-03 17:34:30 +02:00
MechaCat02
5f0d6487ea xenia-kernel: HLE expansion, scheduler integration, audit + UI bridge
Major HLE buildout in exports.rs: KeInitializeSemaphore now seeds
count/limit, XexGet{Module,Procedure}Address use distinct
HMODULE_XBOXKRNL/HMODULE_XAM pseudo-handles with a reverse
(ModuleId,ordinal)→thunk_addr map, plus sweeping additions across
sync primitives, file I/O, semaphores, events, threads, and
allocator paths needed to advance Sylpheed past VdSwap=2.

New modules:
  - thread.rs   — ThreadRef + per-thread suspension/wake plumbing
  - interrupts.rs — IRQ delivery, pending-IRQ slots, IPI helpers
  - path.rs     — guest path normalization (D:\\, game:\\, etc.)
  - audit.rs    — --trace-handles harness backing the handle audit
  - ui_bridge.rs — kernel-side endpoint of the xenia-ui bridge
                   (input snapshots, framebuffer publish handles)

state.rs grows to own the HW-slot scheduler state, the new audit /
UI bridge handles, and the per-handle reverse maps. xam.rs and
objects.rs follow suit for the HLE additions.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-01 16:29:00 +02:00