lei.chen/myxce
1
0
Fork 1
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

feat(scheduler-core): implement scheduler-side admin request handler (task 9.4)

Browse source 
Implements the scheduler's first request-reply opcode (OPCode_schedAdmin).
sched_handle_admin_request() (handler.c) decodes SchedAdminRequest and
dispatches by action: recordStatus answers synchronously (pure read);
recordStart/recordStop are deferred onto the existing pend_updates queue
(XCE_SCHED_OP_ADMIN_RECORD) since sched_record_start()'s snapshot call
requires the session_active==0 precondition only guaranteed on the driver
thread, not the async request-handling thread. driver.c's
xce_sched_driver_translate_pending_events() performs the deferred action
and sends the reply via a new xcecli_reply_schedadmin() (client.c/client.h),
correlated by seq copied before the original request is freed.

Adversarial review found a genuine cross-thread race: sched_record_status()
read driver-owned recording state (including a pointer the driver thread
frees) from the vtask thread with no lock -- the codebase's first such
race, missed by ASan (doesn't detect races). Fixed with a dedicated
record_lock scoped strictly to in-memory field access, never spanning file
I/O; sched_record_status() now strdup()s under the lock instead of
returning a borrowed live pointer. Verified with a real two-thread
lock-contention test (independently confirmed non-vacuous by removing the
lock and observing the test fail) plus a deterministic use-after-free
reproduction.

26/26 scheduler suite, clang-format clean.
This commit is contained in:
Rongsong Shen 2026-08-05 14:11:43 +00:00
parent 7494542a60
commit e819a50600
Signed by: rshen
SSH key fingerprint: SHA256:8Vf2pZ3h6rJa7EhGK+WaAQ9Mta/apZvteW6g9U/WKKk
19 changed files with 1761 additions and 115 deletions
Download patch file Download diff file Expand all files Collapse all files

34
src/lib/client.c
View file

@ -969,6 +969,40 @@ int xcecli_reply_fetchfile(xcecli_ctx_t c, xce_request_t* request,
return xce_reply(&(ctx->ep), &(ctx->ctx.myinfo), &reply);
}
/*
* xcecli_reply_schedadmin - see client.h's declaration comment for the full
* contract (scheduler-core spec, task 9.4, Req 5 AC 10). Builds the
* RequestReply envelope directly (no init_reply_by_req(): unlike
* xcecli_reply_fetchfile() above, the caller may not have a live
* xce_request_t any more -- recordStart/recordStop replies are sent from
* the driver thread, after the original request has already been freed).
* `reply.status` is always 0: a successfully-built SchedAdminReply is
* always a valid RPC response, whether its own `.ok` field is true or
* false (business-level success/failure lives inside the SchedAdminReply
* payload itself, per its own `ok`/`error` fields -- same convention
* handle_config_request() (controller/config_repl.c) uses for
* ReplConfigReply's "up to date" case).
*/
int xcecli_reply_schedadmin(xcecli_ctx_t c, uint64_t seq,
sched_admin_reply_t* areply)
{
api_ctx_t* ctx = (api_ctx_t*)c;
xce_reply_t reply;
if ((ctx == NULL) || (areply == NULL)) {
return -EINVAL;
}
memset(&reply, 0, sizeof(reply));
reply.seq = seq;
reply.opcode = OPCode_schedAdmin;
reply.status = 0;
reply.data_which = RequestReply_data_schedadminreplymsg;
reply.data.schedadminreplymsg = areply;
return xce_reply(&(ctx->ep), &(ctx->ctx.myinfo), &reply);
}
int xcecli_fetchfile(xcecli_ctx_t c, xce_fetchfile_t* msg,
xce_fetchfile_reply_t** reply)
{