diff options
Diffstat (limited to 'rts/Schedule.c')
| -rw-r--r-- | rts/Schedule.c | 38 |
1 files changed, 31 insertions, 7 deletions
diff --git a/rts/Schedule.c b/rts/Schedule.c index 552c2c9ca6..ed4d4b089e 100644 --- a/rts/Schedule.c +++ b/rts/Schedule.c @@ -2016,9 +2016,22 @@ workerStart(Task *task) // schedule() runs without a lock. cap = schedule(cap,task); - // On exit from schedule(), we have a Capability. - releaseCapability(cap); + // On exit from schedule(), we have a Capability, but possibly not + // the same one we started with. + + // During shutdown, the requirement is that after all the + // Capabilities are shut down, all workers that are shutting down + // have finished workerTaskStop(). This is why we hold on to + // cap->lock until we've finished workerTaskStop() below. + // + // There may be workers still involved in foreign calls; those + // will just block in waitForReturnCapability() because the + // Capability has been shut down. + // + ACQUIRE_LOCK(&cap->lock); + releaseCapability_(cap,rtsFalse); workerTaskStop(task); + RELEASE_LOCK(&cap->lock); } #endif @@ -2121,7 +2134,6 @@ exitScheduler( shutdownCapability(&capabilities[i], task, wait_foreign); } boundTaskExiting(task); - stopTaskManager(); } #endif } @@ -2129,11 +2141,23 @@ exitScheduler( void freeScheduler( void ) { - freeCapabilities(); - freeTaskManager(); - if (n_capabilities != 1) { - stgFree(capabilities); + nat still_running; + + ACQUIRE_LOCK(&sched_mutex); + still_running = freeTaskManager(); + // We can only free the Capabilities if there are no Tasks still + // running. We might have a Task about to return from a foreign + // call into waitForReturnCapability(), for example (actually, + // this should be the *only* thing that a still-running Task can + // do at this point, and it will block waiting for the + // Capability). + if (still_running == 0) { + freeCapabilities(); + if (n_capabilities != 1) { + stgFree(capabilities); + } } + RELEASE_LOCK(&sched_mutex); #if defined(THREADED_RTS) closeMutex(&sched_mutex); #endif |