With fewer than six virtual cores a thread pinned to a core at or above the count runs on core (c mod count), and GetCurrentProcessorNumber told it that virtual core's number. The game keys per-core data by the number without locks, so with four cores a thread pinned to core 5 used core 1's data in turn with core 1's own threads, and the game died within seconds of the first frame in play. The Steam Deck profile sets four cores, so this was every start under that profile (issue #445). The call now answers with one of the thread's own cores that fold onto the virtual core it holds, its ideal core first; with all six cores the answer is as before.
The kernel probe gets a test with two threads pinned to each of the six cores: with 6, 4, 3 and 1 virtual cores no thread sees another core's number and no two see the same at once.
Co-Authored-By: Claude Fable 5.2 <noreply@anthropic.com>
Found by profiling a play session and reading the kernel and the command recording:
- nvn_api_cmd.c: a released recording copy had its pins uncounted (a walk over every op) and was freed while copy_lock was held exclusively; the main-loop thread waited for that lock 2.8% of its time. The copies are now chained under the lock and freed after it. The walks over a recording's records test a mask of the five op kinds that name pins before calling op_pins.
- kernel.c: SleepThread(0) took the kernel lock and computed the caller's inherited priority, a scan over every blocked thread, also when no thread waited for a core, which is nearly always. It now yields at once then. A wait without a timeout no longer reads the clock.
- nvn_api_obj.c sleep_until: the wait for a paced frame's slot slept coarsely and left the last 1 to 2 ms to a yield loop; the high-resolution wait now takes all but its own margin.
- input.c: the keyboard scan (a system call per key) is reused for reads within a millisecond.
- nvn_api_core.c: the read-lock observer's commit-point address is 1.2.1's and is now only compared there.
- kernel_probe.c: the probe expected three virtual cores and wait type 3 to be refused; the kernel has six cores and implements the 64-bit wait. It now checks both as they are, counts a core number past the cores as a clash without unbalancing core 0, and --probe-kernel passes again.
Co-Authored-By: Claude Fable 5.2 <noreply@anthropic.com>
(cherry picked from commit a3dbd63878d7d6de096ceb4c25988192b4bce738)
Each file that contains copied code names its copyright holder and license and points at THIRD_PARTY_NOTICES.md; zlib code keeps its full notice and the mark that it was altered. Comments and probe text only.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Comments say what the code does and why, docs/maxwell.md keeps the Maxwell facts, and fetch_refs.sh clones only the checkout the build reads. Code is unchanged.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
