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| author | Rickard Green <[email protected]> | 2010-02-03 01:11:38 +0000 |
|---|---|---|
| committer | Erlang/OTP <[email protected]> | 2010-02-03 01:11:38 +0000 |
| commit | 768da5a5f6312496b9b8a09cca5ea1d6b89a2c1c (patch) | |
| tree | bb7f0b01f75f5f21dcb2f402e2d01b1665a21c2b /erts | |
| parent | 153e2047d734297df3c55b6fa8bda83fb33c72bd (diff) | |
| download | otp-768da5a5f6312496b9b8a09cca5ea1d6b89a2c1c.tar.gz otp-768da5a5f6312496b9b8a09cca5ea1d6b89a2c1c.tar.bz2 otp-768da5a5f6312496b9b8a09cca5ea1d6b89a2c1c.zip | |
OTP-8386 Immediately repeated multi-scheduling block/unblock cycles using
erlang:system_flag(multi_scheduling, block | unblock) could
deadlock the runtime system.
Diffstat (limited to 'erts')
| -rw-r--r-- | erts/emulator/beam/erl_process.c | 38 |
1 files changed, 29 insertions, 9 deletions
diff --git a/erts/emulator/beam/erl_process.c b/erts/emulator/beam/erl_process.c index b519b39d63..2789691c55 100644 --- a/erts/emulator/beam/erl_process.c +++ b/erts/emulator/beam/erl_process.c @@ -2765,7 +2765,7 @@ erts_block_multi_scheduling(Process *p, ErtsProcLocks plocks, int on, int all) p->flags |= F_HAVE_BLCKD_MSCHED; ASSERT(erts_smp_atomic_read(&schdlr_sspnd.active) == 1); ASSERT(p->scheduler_data->no == 1); - res = 1; + res = ERTS_SCHDLR_SSPND_DONE_MSCHED_BLOCKED; } else { p->flags |= F_HAVE_BLCKD_MSCHED; @@ -2896,12 +2896,16 @@ erts_block_multi_scheduling(Process *p, ErtsProcLocks plocks, int on, int all) #endif p->flags &= ~F_HAVE_BLCKD_MSCHED; erts_smp_atomic_set(&schdlr_sspnd.msb.ongoing, 0); - if (schdlr_sspnd.online == 1) - /* No schedulers to resume */; + if (schdlr_sspnd.online == 1) { + /* No schedulers to resume */ + ASSERT(erts_smp_atomic_read(&schdlr_sspnd.active) == 1); + schdlr_sspnd.changing = 0; + } else if (erts_common_run_queue) { for (ix = 1; ix < schdlr_sspnd.online; ix++) erts_smp_atomic_set(&ERTS_SCHEDULER_IX(ix)->suspended, 0); wake_all_schedulers(); + erts_smp_cnd_broadcast(&schdlr_sspnd.cnd); } else { int online = schdlr_sspnd.online; @@ -2933,8 +2937,8 @@ erts_block_multi_scheduling(Process *p, ErtsProcLocks plocks, int on, int all) erts_smp_runq_unlock(ERTS_RUNQ_IX(0)); erts_smp_mtx_unlock(&balance_info.update_mtx); erts_smp_mtx_lock(&schdlr_sspnd.mtx); + erts_smp_cnd_broadcast(&schdlr_sspnd.cnd); } - erts_smp_cnd_broadcast(&schdlr_sspnd.cnd); res = ERTS_SCHDLR_SSPND_DONE; } } @@ -8033,11 +8037,6 @@ erts_do_exit_process(Process* p, Eterm reason) if (p->bif_timers) erts_cancel_bif_timers(p, ERTS_PROC_LOCKS_ALL); -#ifdef ERTS_SMP - if (p->flags & F_HAVE_BLCKD_MSCHED) - erts_block_multi_scheduling(p, ERTS_PROC_LOCKS_ALL, 0, 1); -#endif - erts_smp_proc_unlock(p, ERTS_PROC_LOCKS_ALL_MINOR); #ifdef ERTS_SMP @@ -8082,6 +8081,27 @@ continue_exit_process(Process *p erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS); #endif +#ifdef ERTS_SMP + if (p->flags & F_HAVE_BLCKD_MSCHED) { + ErtsSchedSuspendResult ssr; + ssr = erts_block_multi_scheduling(p, ERTS_PROC_LOCK_MAIN, 0, 1); + switch (ssr) { + case ERTS_SCHDLR_SSPND_YIELD_RESTART: + goto yield; + case ERTS_SCHDLR_SSPND_DONE_MSCHED_BLOCKED: + case ERTS_SCHDLR_SSPND_YIELD_DONE_MSCHED_BLOCKED: + case ERTS_SCHDLR_SSPND_DONE: + case ERTS_SCHDLR_SSPND_YIELD_DONE: + p->flags &= ~F_HAVE_BLCKD_MSCHED; + break; + case ERTS_SCHDLR_SSPND_EINVAL: + default: + erl_exit(ERTS_ABORT_EXIT, "%s:%d: Internal error: %d\n", + __FILE__, __LINE__, (int) ssr); + } + } +#endif + if (p->flags & F_USING_DB) { if (erts_db_process_exiting(p, ERTS_PROC_LOCK_MAIN)) goto yield; |