Three-layer regression guard (test_sim_isolation.c) proving sim.h/sim.c/
sim_loop.c hold no controller-facing client/cluster-config/capnp-socket
state: source-text scan, struct-body field scan, and nm(1) link-time
undefined-symbol audit of a new isolated sched_sim_isolation_lib target.
Add sim_loop.c implementing sched_sim_driver_run(): decode .replay
messages in file order, jump the virtual clock to each ReplayEvent's
exact timestamp as it's queued, and run a real push-events/go/drain/
end-session cycle on each ReplaySession boundary (AC 14, AC 18).
Task 11.1 left no picker registered against the isolated core and no
thread backing its cbufs, which deadlocks the decision drain the moment
a real event loop exists. Add plugin_register_core() (registers a
picker against a bare xce_sched_core_t*, no xce_scheduler_t* required)
and extract builtin_fcfs_new_plugin() from register_builtin_fcfs() as a
behavior-preserving factory, plus a picker-driving thread for the sim
driver. Since real resource allocation is unreachable without a live
xce_scheduler_t* (scheduler-allocation spec's job), the sim picker
thread conservatively PENDs every candidate rather than dispatching.
28/28 scheduler suite, 32/32 whole-project tests green.
Add sim.h/sim.c implementing AC 13 steps 1-4: open+validate ReplayHeader,
locate the most recent SnapshotEntry at/before --sim-start-ts, load it via
xce_sched_core_load_snapshot(), and set the virtual clock anchors. Wire
all seven simulation CLI flags into main.c's task-5.2 mode-selection
branch. Event loop itself (step 5) deferred to task 11.2. Fixes two real
bugs found during TDD: a SnapshotEntry_get_ts() use-after-free and a
pend_updates NULL-deref in xce_sched_core_fini() for bare-core callers.
27/27 scheduler suite green, full project build clean.
Adds recording-state fields directly to xce_scheduler_t (no new
xce_sched_driver_t type, per task 9.1's precedent). sched_record_start()/
sched_record_stop() implement AC 10: validate via task 9.1's path
validator, open with a TOCTOU-hardened sequence (O_NOFOLLOW, no O_TRUNC,
fstat()+st_nlink==1 check before ftruncate()), snapshot the core, write
ReplayHeader+SnapshotEntry on start, ReplayEvent{endSession} on stop.
driver.c gains boolean-gated recording hooks in
xce_sched_driver_translate_pending_events() (per-event-batch ReplayEvent
writes, new recording_events.c) and xce_sched_driver_run_normal_mode_round()
(per-session ReplaySession writes, new recording_session.c) -- zero I/O/
allocation when inactive.
Two real bugs found and fixed during implementation: bug-1498 (O_TRUNC
would have truncated a hard-linked victim file before the TOCTOU check
could reject it) and bug-1499 (a transient edit dropped
xce_core_signal_go(), causing a 3-way thread deadlock).
test_record_lifecycle.c decodes the full start->events->session->stop
cycle with the real capnp decoders and asserts the exact message
sequence; TOCTOU regression tests use real symlink(2)/link(2) syscalls.
25/25 scheduler suite, clang-format clean.
Adds --record-dir CLI flag and sched_validate_record_filename() with
canonical-path containment (realpath()-based, not textual-prefix) plus
separator/".." rejection before any filesystem access.
Adversarial review found and this task fixed two CWE-59 inode-aliasing
bypasses: a direct hard link inside record_dir aliasing an outside file,
and a compound variant where a symlink pointed at an in-directory file
itself hard-linked outside record_dir. Both closed via st_nlink checks
on the direct entry and the fully-resolved symlink target respectively,
each verified with a live RED->GREEN reproduction. TOCTOU residual risk
documented and deferred to task 9.2 (O_NOFOLLOW + fstat() re-check).
18/18 recording subtests, 24/24 scheduler suite, clang-format clean.
Adds xce_sched_core_save_snapshot()/xce_sched_core_load_snapshot(),
split across snapshot.c/snapshot_wire.c/snapshot_load.c (800-line cap)
along real save/load/shared-helper boundaries. Serializes the full
core state (config, jobs, queues, workers, resources, resvals, users,
projects, prng_seed, internal_state) into/out of sched_snapshot_data_t
(task 7.3's committed C mirror of the capnp SnapshotData struct) as
plain in-memory structures -- no wire encoding here, that's a later
task. After load, rebuilds the picker's private state by re-invoking
its state-change hooks (queue updates, then job pushes) against the
restored core state, matching xce_core_push_events()'s own hook-firing
order; picker-private state itself is never stored in the snapshot.
Adds a new prng_seed field to xce_sched_core_t -- requirements.md/
design.md both presuppose it but no prior task added it. Seeded to 0,
no PRNG consumer wired yet (deliberately out of scope).
Cross-core behavioral-equivalence proven directly: two independent
cores, each with its own registered picker, save on one and load into
a freshly-initialized other, both driven through an identical real
session, decision sequences asserted identical in order.
Found and fixed two real bugs along the way: a missing prng_seed
restore in this task's own new code, and a genuine guard bug in
already-committed core.c (sched_get_user()/sched_get_project()
treating key_find()'s expected -ENOENT as fatal, silently breaking
get-or-create for any new name) that also affects the live production
path (make_sched_job(), JOBS_PUSH) -- a narrowly-scoped two-line fix,
independently traced to the primitive level and confirmed correct by
review.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019dw5WnN3DXStaEaPYfACU1
Adds driver.h/driver.c: xce_sched_driver_translate_pending_events()
drains core->pend_updates via the existing dataq-swap pattern (same
mechanism sched_update() uses), translates all 10 xce_sched_update_
request_t op types into the matching xce_core_event_t, and pushes the
batch through xce_core_push_events(). Scoped to xce_sched_core_t*
alone -- pend_updates already lives on core since task 4.1, and this
task is translation-only (no decision publishing, no mode-selection,
no recording -- all later work). handler.c (the enqueue side) is
untouched. First task in Group 5 (Core: Normal-Mode Driver).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019dw5WnN3DXStaEaPYfACU1
Adds xce_core_now() (new core_clock.c, kept separate from core.c so
test_core_isolation.c's wall-clock scan still enforces zero direct
clock_gettime()/time() calls elsewhere in the core): the two-anchor
plus speed formula (virtual_clock_base + (elapsed * speed_num) /
speed_den), covering all four modes (normal, discrete/real-time/fast-
slow simulation) via four new atomic fields on xce_sched_core_t,
defaulted to normal-mode (1/1 speed) in xce_sched_core_init().
requirements.md's literal tlog_reg_format_func(fn, core_ptr) call
shape doesn't exist in the real vendored tlog library (registration
takes only the callback; userptr is per-call-site, not bindable at
registration) -- resolved with a module-level active-core pointer read
by a new core-scoped format function, not wired into mylog_init()/
main.c yet. xce_core_go()/xce_core_end_session() (task 4.4) now stamp
session_start/compute session_duration_ns via xce_core_now(), with
their existing session-active/reentrancy behavior untouched.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019dw5WnN3DXStaEaPYfACU1
Adds xce_core_go()/xce_core_end_session() (new core_session.c):
xce_core_go() is non-blocking, performs begin-session state reset
(select-eval-ctx, resval resets), signals the picker thread via wbuf,
and returns -EINVAL on a reentrant call while a session is already
active (proven a true no-op, not just an early return). Draining
core->decisions and invoking the driver's on_decision callback is the
driver's own responsibility between core_go() and core_end_session()
(confirmed driver-owned, not core-owned, per the Driver <-> Core
protocol). xce_core_set_decision_cb() registers the callback + driver
context as a separate setter, keeping xce_sched_core_init()'s live
sched_init() call site untouched. Adds XCE_DECISION_PREEMPT to
decision.h (jobid/victims[]/reason) alongside the existing DISPATCH/
PEND types. Additive only — sched_go/sched_begin_session/
sched_end_session/sched_allocator/main.c remain untouched.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019dw5WnN3DXStaEaPYfACU1
Defines xce_core_event_type_t/xce_core_event_t (9 event kinds: config,
job, worker, resource, resval full/delta, job state change, job update,
queue update, job rusage) in core.h. Implements xce_core_push_events()
in a new core_events.c (split out of core.c to stay under the 800-line
cap): rejects -EBUSY mid-session, otherwise applies each event's core-
state mutation and fires the corresponding picker hook synchronously,
exactly once per event, before returning. CONFIG_PUSH decomposes the
pushed config's embedded queues/resources/resvals via shared helpers
(also reused by QUEUE_UPDATE's upsert path), mirroring the existing
sched_init_config()/sched_init_resources()/sched_init_sharedInst()/
sched_init_queues(). Narrows sched_resolve_job_picker() to take
xce_sched_core_t* (pure type change, zero behavior change). Purely
additive — not wired into the live scheduling path yet (task 5.x).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019dw5WnN3DXStaEaPYfACU1
Splits xce_scheduler_t along the controller-I/O seam: xce_sched_core_t
(new core.h/core.c) now holds all scheduling state (jobs/queues/workers/
users/projects/resource managers/plugins/three-thread-cbuf pipeline),
while xce_scheduler_t shrinks to {core; apictx; cluster_cfg}. Proven via
an nm-based link-time isolation test (zero netio/xcecli/idgen/delaymgr
symbols reachable from core.c) plus a reproducible wall-clock-call guard.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019dw5WnN3DXStaEaPYfACU1
Registers builtin_fcfs at scheduler startup and makes it the default
job_pick_plugin, replacing the hardcoded "xce_sched_fcfs" literal in
sched_job_picker() with a fail-loud lookup through sched_resolve_job_picker().
The picker thread now branches legacy job_elect_fn plugins (delegated
unchanged, preserving their self-contained wbuf-driven loop) from native
xce_job_picker_iface_t pickers (driven by a new per-session loop), and the
allocator now calls on_dispatch/on_pend for every picker as Req 1 AC 4
requires. Closes task 2.3's flagged picker/allocator concurrency race with a
mutex on fcfs_plugin_data_t, and adds cancel points to next_job().
- Fix issue to xce_get() api cause client side crash
- add parse resreq section
- add rusage parser
- parse resreq with basic support alternative & compound, still miss select
