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authorLukas Larsson <[email protected]>2019-01-23 10:22:17 +0100
committerLukas Larsson <[email protected]>2019-01-23 10:22:17 +0100
commitaba6a2c2b5ae9dca21c5e14f5c25b175c6b67782 (patch)
treef8d2df95eed18df1a2402488fefd8aa10df9897f
parent3aba68193ab414cd807fe0757a6b6f8f20bd57ef (diff)
parenta53f58ff4fc68f069c395966a0b7375523c77b65 (diff)
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Merge branch 'lukas/erts/scheduler-pollset-fixes/OTP-15538' into maint
* lukas/erts/scheduler-pollset-fixes/OTP-15538: erts: Fix getting of poll events on linux >= 4.15.0 erts: Use reduction based polling for starved poll-set erts: Fix pollset test cases
-rw-r--r--erts/emulator/beam/erl_process.c86
-rw-r--r--erts/emulator/beam/erl_process.h2
-rw-r--r--erts/emulator/sys/common/erl_check_io.c4
-rw-r--r--erts/emulator/sys/common/erl_poll.c10
-rw-r--r--erts/emulator/test/driver_SUITE.erl19
-rw-r--r--erts/emulator/test/scheduler_SUITE.erl27
-rw-r--r--erts/emulator/test/z_SUITE.erl2
7 files changed, 71 insertions, 79 deletions
diff --git a/erts/emulator/beam/erl_process.c b/erts/emulator/beam/erl_process.c
index 19093ebfdd..dca502c939 100644
--- a/erts/emulator/beam/erl_process.c
+++ b/erts/emulator/beam/erl_process.c
@@ -340,6 +340,7 @@ 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;
@@ -3247,6 +3248,7 @@ 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);
}
@@ -3269,28 +3271,6 @@ 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
@@ -3448,6 +3428,7 @@ 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)) {
@@ -4711,15 +4692,6 @@ 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;
}
@@ -5239,19 +5211,6 @@ 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;
@@ -5261,8 +5220,6 @@ 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;
@@ -5272,7 +5229,7 @@ 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;
@@ -5923,6 +5880,7 @@ 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);
@@ -9277,7 +9235,7 @@ 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;
@@ -9351,6 +9309,10 @@ 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);
@@ -9567,7 +9529,33 @@ 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 0aa19e7bde..43937f216c 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)
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/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);
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.