From be39c49819ea2031f7d11647f34a3519198932e8 Mon Sep 17 00:00:00 2001 From: Lukas Larsson Date: Wed, 12 Dec 2018 09:40:22 +0100 Subject: erts: Fix pollset test cases --- erts/emulator/sys/common/erl_check_io.c | 4 ++-- erts/emulator/test/driver_SUITE.erl | 19 ++++++++++++------- erts/emulator/test/scheduler_SUITE.erl | 27 +++++++++++++-------------- erts/emulator/test/z_SUITE.erl | 2 +- 4 files changed, 28 insertions(+), 24 deletions(-) (limited to 'erts') diff --git a/erts/emulator/sys/common/erl_check_io.c b/erts/emulator/sys/common/erl_check_io.c index c681fa481f..ac9a070bce 100644 --- a/erts/emulator/sys/common/erl_check_io.c +++ b/erts/emulator/sys/common/erl_check_io.c @@ -2262,14 +2262,14 @@ erts_check_io_info(void *proc) #if ERTS_POLL_USE_FALLBACK erts_poll_info_flbk(get_fallback_pollset(), &piv[0]); - piv[0].poll_threads = 1; + piv[0].poll_threads = 0; piv[0].active_fds = 0; piv++; #endif #if ERTS_POLL_USE_SCHEDULER_POLLING erts_poll_info(get_scheduler_pollset(0), &piv[0]); - piv[0].poll_threads = 1; + piv[0].poll_threads = 0; piv[0].active_fds = 0; piv++; #endif diff --git a/erts/emulator/test/driver_SUITE.erl b/erts/emulator/test/driver_SUITE.erl index bd62708aa7..1d2ae4fb51 100644 --- a/erts/emulator/test/driver_SUITE.erl +++ b/erts/emulator/test/driver_SUITE.erl @@ -1069,14 +1069,19 @@ get_stable_check_io_info(N) -> get_check_io_total(ChkIo) -> ct:log("ChkIo = ~p~n",[ChkIo]), {Fallback, Rest} = get_fallback(ChkIo), + OnlyPollThreads = [PS || PS <- Rest, not is_scheduler_pollset(PS)], add_fallback_infos(Fallback, - lists:foldl(fun(Pollset, Acc) -> - lists:zipwith(fun(A, B) -> - add_pollset_infos(A,B) - end, - Pollset, Acc) - end, - hd(Rest), tl(Rest))). + lists:foldl( + fun(Pollset, Acc) -> + lists:zipwith(fun(A, B) -> + add_pollset_infos(A,B) + end, + Pollset, Acc) + end, + hd(OnlyPollThreads), tl(OnlyPollThreads))). + +is_scheduler_pollset(Pollset) -> + proplists:get_value(poll_threads, Pollset) == 0. add_pollset_infos({Tag, A}=TA , {Tag, B}=TB) -> case tag_type(Tag) of diff --git a/erts/emulator/test/scheduler_SUITE.erl b/erts/emulator/test/scheduler_SUITE.erl index 2e0dfa42f3..f61949c75b 100644 --- a/erts/emulator/test/scheduler_SUITE.erl +++ b/erts/emulator/test/scheduler_SUITE.erl @@ -1450,28 +1450,26 @@ poll_threads(Config) when is_list(Config) -> {Conc, PollType, KP} = get_ioconfig(Config), {Sched, SchedOnln, _} = get_sstate(Config, ""), + [1, 1] = get_ionum(Config,"+IOt 2 +IOp 2"), + [1, 1, 1, 1, 1] = get_ionum(Config,"+IOt 5 +IOp 5"), + [1, 1] = get_ionum(Config, "+S 2 +IOPt 100 +IOPp 100"), + if Conc -> - [1, 1, 1] = get_ionum(Config,"+IOt 2 +IOp 2"), - [1, 1, 1, 1, 1, 1] = get_ionum(Config,"+IOt 5 +IOp 5"), - [1, 1, 1] = get_ionum(Config, "+S 2 +IOPt 100 +IOPp 100"), - [5, 1] = get_ionum(Config,"+IOt 5 +IOp 1"), - [3, 2, 1] = get_ionum(Config,"+IOt 5 +IOp 2"), - [2, 2, 2, 2, 2, 1] = get_ionum(Config,"+IOt 10 +IOPp 50"), + [5] = get_ionum(Config,"+IOt 5 +IOp 1"), + [3, 2] = get_ionum(Config,"+IOt 5 +IOp 2"), + [2, 2, 2, 2, 2] = get_ionum(Config,"+IOt 10 +IOPp 50"), - [2, 1] = get_ionum(Config, "+S 2 +IOPt 100"), - [4, 1] = get_ionum(Config, "+S 4 +IOPt 100"), - [4, 1] = get_ionum(Config, "+S 4:2 +IOPt 100"), - [4, 4, 1] = get_ionum(Config, "+S 8 +IOPt 100 +IOPp 25"), + [2] = get_ionum(Config, "+S 2 +IOPt 100"), + [4] = get_ionum(Config, "+S 4 +IOPt 100"), + [4] = get_ionum(Config, "+S 4:2 +IOPt 100"), + [4, 4] = get_ionum(Config, "+S 8 +IOPt 100 +IOPp 25"), fail = get_ionum(Config, "+IOt 1 +IOp 2"), ok; not Conc -> - [1, 1] = get_ionum(Config,"+IOt 2 +IOp 2"), - [1, 1, 1, 1, 1] = get_ionum(Config,"+IOt 5 +IOp 5"), - [1, 1] = get_ionum(Config, "+S 2 +IOPt 100 +IOPp 100"), [1, 1, 1, 1, 1] = get_ionum(Config,"+IOt 5 +IOp 1"), [1, 1, 1, 1, 1] = get_ionum(Config,"+IOt 5 +IOp 2"), @@ -1515,7 +1513,8 @@ get_iostate(Config, Cmd)-> erlang:system_info(check_io) end]), IO = [IOState || IOState <- IOStates, - proplists:get_value(fallback, IOState) == false], + proplists:get_value(fallback, IOState) == false, + proplists:get_value(poll_threads, IOState) /= 0], stop_node(Node), IO; {error,timeout} -> diff --git a/erts/emulator/test/z_SUITE.erl b/erts/emulator/test/z_SUITE.erl index 1c52e1a934..6549108126 100644 --- a/erts/emulator/test/z_SUITE.erl +++ b/erts/emulator/test/z_SUITE.erl @@ -251,7 +251,7 @@ pollset_size(Config) when is_list(Config) -> end. check_io_debug(Config) when is_list(Config) -> - case lists:keysearch(name, 1, erlang:system_info(check_io)) of + case lists:keysearch(name, 1, hd(erlang:system_info(check_io))) of {value, {name, erts_poll}} -> check_io_debug_test(); _ -> {skipped, "Not implemented in this emulator"} end. -- cgit v1.2.3 From adec898daf9223484f5900f7d247cbaff6f4a11b Mon Sep 17 00:00:00 2001 From: Lukas Larsson Date: Mon, 7 Jan 2019 14:38:48 +0100 Subject: erts: Use reduction based polling for starved poll-set When the schedulers never go to sleep (and thus never polls) it may be that the fds in schedulers poll-sets are never polled. Before this commit, this was solved by starting a timer when an overload was detected. This had issues as overloads were not always detected in time. So this commit reverts to the pre OTP-21 behaviour so keep a global counter makes that the poll is called when it should. --- erts/emulator/beam/erl_process.c | 86 +++++++++++++++++----------------------- erts/emulator/beam/erl_process.h | 2 - 2 files changed, 37 insertions(+), 51 deletions(-) (limited to 'erts') diff --git a/erts/emulator/beam/erl_process.c b/erts/emulator/beam/erl_process.c index 2427d87f66..73c99f7fb0 100644 --- a/erts/emulator/beam/erl_process.c +++ b/erts/emulator/beam/erl_process.c @@ -344,6 +344,7 @@ erts_sched_stat_t erts_sched_stat; static erts_tsd_key_t ERTS_WRITE_UNLIKELY(sched_data_key); #if ERTS_POLL_USE_SCHEDULER_POLLING +static erts_atomic32_t function_calls; static erts_atomic32_t doing_sys_schedule; #endif static erts_atomic32_t no_empty_run_queues; @@ -3251,6 +3252,7 @@ poll_thread(void *arg) static ERTS_INLINE void clear_sys_scheduling(void) { + erts_atomic32_set_relb(&function_calls, 0); erts_atomic32_set_mb(&doing_sys_schedule, 0); } @@ -3273,28 +3275,6 @@ prepare_for_sys_schedule(void) return 0; } -static void -check_io_timer(void *null) -{ - ErtsSchedulerData *esdp = erts_get_scheduler_data(); - if (prepare_for_sys_schedule()) { - erts_check_io(esdp->ssi->psi, ERTS_POLL_NO_TIMEOUT); - clear_sys_scheduling(); - } - - /* The timer is cleared if this schedulers run-queue became empty - or if the CHECKIO flag was cleared. The CHECKIO flags is cleared - when a check_balance assigns another scheduler to be the poller in - the overload scenario. */ - if ((ERTS_RUNQ_FLGS_GET_NOB(esdp->run_queue) & (ERTS_RUNQ_FLG_OUT_OF_WORK|ERTS_RUNQ_FLG_CHECKIO)) - == ERTS_RUNQ_FLG_CHECKIO) { - erts_start_timer_callback(ERTS_POLL_SCHEDULER_POLLING_TIMEOUT, - check_io_timer, NULL); - } else { - ERTS_RUNQ_FLGS_UNSET(esdp->run_queue, ERTS_RUNQ_FLG_CHECKIO); - } -} - #else #define clear_sys_scheduling() #define prepare_for_sys_schedule() 0 @@ -3406,6 +3386,7 @@ scheduler_wait(int *fcalls, ErtsSchedulerData *esdp, ErtsRunQueue *rq) current_time = erts_get_monotonic_time(esdp); } } + *fcalls = 0; clear_sys_scheduling(); } else { if (!ERTS_SCHEDULER_IS_DIRTY(esdp)) { @@ -4661,15 +4642,6 @@ check_balance(ErtsRunQueue *c_rq) if (blnc_no_rqs == 1) { c_rq->check_balance_reds = INT_MAX; erts_atomic32_set_nob(&balance_info.checking_balance, 0); -#if ERTS_POLL_USE_SCHEDULER_POLLING - c_rq->check_balance_reds = ERTS_RUNQ_CALL_CHECK_BALANCE_REDS; - if ((ERTS_RUNQ_FLGS_GET_NOB(c_rq) & (ERTS_RUNQ_FLG_OUT_OF_WORK|ERTS_RUNQ_FLG_CHECKIO)) - == 0) { - ERTS_RUNQ_FLGS_SET(c_rq, ERTS_RUNQ_FLG_CHECKIO); - erts_start_timer_callback(ERTS_POLL_SCHEDULER_POLLING_TIMEOUT, check_io_timer, NULL); - } - ERTS_RUNQ_FLGS_UNSET(c_rq, ERTS_RUNQ_FLGS_MIGRATION_INFO); -#endif return; } @@ -5189,19 +5161,6 @@ erts_fprintf(stderr, "--------------------------------\n"); /* Publish new migration paths... */ erts_atomic_set_wb(&erts_migration_paths, (erts_aint_t) new_mpaths); -#if ERTS_POLL_USE_SCHEDULER_POLLING - if (full_scheds == current_active) { - ERTS_ASSERT(full_scheds <= current_active); - /* All active schedulers ran for full, we need to do active polling, - so we setup a timer that does active polling */ - if (!(ERTS_RUNQ_FLGS_GET_NOB(c_rq) & ERTS_RUNQ_FLG_CHECKIO)) { - /* Active polling is not running, start it */ - erts_start_timer_callback(ERTS_POLL_SCHEDULER_POLLING_TIMEOUT, check_io_timer, NULL); - } - run_queue_info[c_rq->ix].flags |= ERTS_RUNQ_FLG_CHECKIO; - } -#endif - /* Reset balance statistics in all online queues */ for (qix = 0; qix < blnc_no_rqs; qix++) { Uint32 flags = run_queue_info[qix].flags; @@ -5211,8 +5170,6 @@ erts_fprintf(stderr, "--------------------------------\n"); ASSERT(!(flags & ERTS_RUNQ_FLG_OUT_OF_WORK)); if (rq->waiting) flags |= ERTS_RUNQ_FLG_OUT_OF_WORK; - if (rq != c_rq) - flags &= ~ERTS_RUNQ_FLG_CHECKIO; rq->full_reds_history_sum = run_queue_info[qix].full_reds_history_sum; @@ -5222,7 +5179,7 @@ erts_fprintf(stderr, "--------------------------------\n"); ERTS_DBG_CHK_FULL_REDS_HISTORY(rq); rq->out_of_work_count = 0; - (void) ERTS_RUNQ_FLGS_READ_BSET(rq, ERTS_RUNQ_FLGS_MIGRATION_INFO|ERTS_RUNQ_FLG_CHECKIO, flags); + (void) ERTS_RUNQ_FLGS_READ_BSET(rq, ERTS_RUNQ_FLGS_MIGRATION_INFO, flags); rq->max_len = erts_atomic32_read_dirty(&rq->len); for (pix = 0; pix < ERTS_NO_PRIO_LEVELS; pix++) { ErtsRunQueueInfo *rqi; @@ -5873,6 +5830,7 @@ erts_init_scheduling(int no_schedulers, int no_schedulers_online, int no_poll_th erts_alloc_permanent_cache_aligned(ERTS_ALC_T_RUNQS, size_runqs); #if ERTS_POLL_USE_SCHEDULER_POLLING erts_atomic32_init_nob(&doing_sys_schedule, 0); + erts_atomic32_init_nob(&function_calls, 0); #endif erts_atomic32_init_nob(&no_empty_run_queues, 0); @@ -9217,7 +9175,7 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls) Process *proxy_p = NULL; ErtsRunQueue *rq; int context_reds; - int fcalls; + int fcalls = 0; int actual_reds; int reds; Uint32 flags; @@ -9291,6 +9249,10 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls) reds = ERTS_PROC_MIN_CONTEXT_SWITCH_REDS_COST; esdp->virtual_reds = 0; +#if ERTS_POLL_USE_SCHEDULER_POLLING + fcalls = (int) erts_atomic32_add_read_acqb(&function_calls, reds); +#endif + ASSERT(esdp && esdp == erts_get_scheduler_data()); rq = erts_get_runq_current(esdp); @@ -9507,7 +9469,33 @@ Process *erts_schedule(ErtsSchedulerData *esdp, Process *p, int calls) non_empty_runq(rq); goto check_activities_to_run; - } + } else if (is_normal_sched && + fcalls > (2 * context_reds) && + prepare_for_sys_schedule()) { + ErtsMonotonicTime current_time; + /* + * Schedule system-level activities. + */ + + ERTS_MSACC_PUSH_STATE_CACHED_M(); + + erts_runq_unlock(rq); + + ERTS_MSACC_SET_STATE_CACHED_M(ERTS_MSACC_STATE_CHECK_IO); + LTTNG2(scheduler_poll, esdp->no, 1); + + erts_check_io(esdp->ssi->psi, ERTS_POLL_NO_TIMEOUT); + ERTS_MSACC_POP_STATE_M(); + + current_time = erts_get_monotonic_time(esdp); + if (current_time >= erts_next_timeout_time(esdp->next_tmo_ref)) + erts_bump_timers(esdp->timer_wheel, current_time); + + erts_runq_lock(rq); + fcalls = 0; + clear_sys_scheduling(); + goto continue_check_activities_to_run; + } if (flags & ERTS_RUNQ_FLG_MISC_OP) exec_misc_ops(rq); diff --git a/erts/emulator/beam/erl_process.h b/erts/emulator/beam/erl_process.h index a1b029adbe..9a22858f2a 100644 --- a/erts/emulator/beam/erl_process.h +++ b/erts/emulator/beam/erl_process.h @@ -173,8 +173,6 @@ extern int erts_dio_sched_thread_suggested_stack_size; (((Uint32) 1) << (ERTS_RUNQ_FLG_BASE2 + 9)) #define ERTS_RUNQ_FLG_HALTING \ (((Uint32) 1) << (ERTS_RUNQ_FLG_BASE2 + 10)) -#define ERTS_RUNQ_FLG_CHECKIO \ - (((Uint32) 1) << (ERTS_RUNQ_FLG_BASE2 + 11)) #define ERTS_RUNQ_FLG_MAX (ERTS_RUNQ_FLG_BASE2 + 12) -- cgit v1.2.3 From a53f58ff4fc68f069c395966a0b7375523c77b65 Mon Sep 17 00:00:00 2001 From: Lukas Larsson Date: Mon, 21 Jan 2019 10:24:02 +0100 Subject: erts: Fix getting of poll events on linux >= 4.15.0 --- erts/emulator/sys/common/erl_poll.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) (limited to 'erts') diff --git a/erts/emulator/sys/common/erl_poll.c b/erts/emulator/sys/common/erl_poll.c index 51d50933ff..27ffba58bd 100644 --- a/erts/emulator/sys/common/erl_poll.c +++ b/erts/emulator/sys/common/erl_poll.c @@ -2326,6 +2326,7 @@ uint32_t epoll_events(int kp_fd, int fd) { /* For epoll we read the information about what is selected upon from the proc fs.*/ char fname[30]; + char s[256]; FILE *f; unsigned int pos, flags, mnt_id; int line = 0; @@ -2343,12 +2344,12 @@ uint32_t epoll_events(int kp_fd, int fd) } if (fscanf(f,"\nmnt_id:\t%x\n", &mnt_id)); line += 3; - while (!feof(f)) { + while (fgets(s, sizeof(s) / sizeof(*s), f)) { /* tfd: 10 events: 40000019 data: 180000000a */ int ev_fd; uint32_t events; uint64_t data; - if (fscanf(f,"tfd:%d events:%x data:%llx\n", &ev_fd, &events, + if (sscanf(s,"tfd:%d events:%x data:%llx", &ev_fd, &events, (unsigned long long*)&data) != 3) { fprintf(stderr,"failed to parse file %s on line %d, errno = %d\n", fname, line, @@ -2392,6 +2393,7 @@ ERTS_POLL_EXPORT(erts_poll_get_selected_events)(ErtsPollSet *ps, /* For epoll we read the information about what is selected upon from the proc fs.*/ char fname[30]; + char s[256]; FILE *f; unsigned int pos, flags, mnt_id; int line = 0; @@ -2410,12 +2412,12 @@ ERTS_POLL_EXPORT(erts_poll_get_selected_events)(ErtsPollSet *ps, } if (fscanf(f,"\nmnt_id:\t%x\n", &mnt_id)); line += 3; - while (!feof(f)) { + while (fgets(s, sizeof(s) / sizeof(*s), f)) { /* tfd: 10 events: 40000019 data: 180000000a */ int fd; uint32_t events; uint64_t data; - if (fscanf(f,"tfd:%d events:%x data:%llx\n", &fd, &events, + if (sscanf(s,"tfd:%d events:%x data:%llx", &fd, &events, (unsigned long long*)&data) != 3) { fprintf(stderr,"failed to parse file %s on line %d, errno = %d\n", fname, line, errno); -- cgit v1.2.3