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Diffstat (limited to 'erts/emulator/beam/erl_process.c')
-rw-r--r--erts/emulator/beam/erl_process.c228
1 files changed, 118 insertions, 110 deletions
diff --git a/erts/emulator/beam/erl_process.c b/erts/emulator/beam/erl_process.c
index b0db2da243..dad4006beb 100644
--- a/erts/emulator/beam/erl_process.c
+++ b/erts/emulator/beam/erl_process.c
@@ -7156,129 +7156,72 @@ erts_schedule_process(Process *p, erts_aint32_t state, ErtsProcLocks locks)
schedule_process(p, state, locks);
}
-static int
-schedule_process_sys_task(Process *p, erts_aint32_t prio, ErtsProcSysTask *st,
- erts_aint32_t *fail_state_p)
-{
- int res;
- int locked;
- ErtsProcSysTaskQs *stqs, *free_stqs;
- erts_aint32_t fail_state, state, a, n, enq_prio;
+/* Enqueues the given sys task on the process and schedules it. The task may be
+ * NULL if only scheduling is desired. */
+static ERTS_INLINE erts_aint32_t
+active_sys_enqueue(Process *p, ErtsProcSysTask *sys_task,
+ erts_aint32_t task_prio, erts_aint32_t enable_flags,
+ erts_aint32_t state, erts_aint32_t *fail_state_p)
+{
+ int runnable_procs = erts_system_profile_flags.runnable_procs;
+ erts_aint32_t n, a, enq_prio, fail_state;
+ int already_scheduled;
+ int status_locked;
int enqueue; /* < 0 -> use proxy */
- unsigned int prof_runnable_procs;
+ enable_flags |= ERTS_PSFLG_ACTIVE_SYS;
fail_state = *fail_state_p;
-
- res = 1; /* prepare for success */
- st->next = st->prev = st; /* Prep for empty prio queue */
- state = erts_smp_atomic32_read_nob(&p->state);
- prof_runnable_procs = erts_system_profile_flags.runnable_procs;
- locked = 0;
- free_stqs = NULL;
- if (state & ERTS_PSFLG_ACTIVE_SYS)
- stqs = NULL;
- else {
- alloc_qs:
- stqs = proc_sys_task_queues_alloc();
- stqs->qmask = 1 << prio;
- stqs->ncount = 0;
- stqs->q[PRIORITY_MAX] = NULL;
- stqs->q[PRIORITY_HIGH] = NULL;
- stqs->q[PRIORITY_NORMAL] = NULL;
- stqs->q[PRIORITY_LOW] = NULL;
- stqs->q[prio] = st;
- }
-
- if (!locked) {
- locked = 1;
- erts_smp_proc_lock(p, ERTS_PROC_LOCK_STATUS);
-
- state = erts_smp_atomic32_read_nob(&p->state);
- if (state & fail_state) {
- *fail_state_p = (state & fail_state);
- free_stqs = stqs;
- res = 0;
- goto cleanup;
- }
- }
-
- if (!p->sys_task_qs) {
- if (stqs)
- p->sys_task_qs = stqs;
- else
- goto alloc_qs;
- }
- else {
- free_stqs = stqs;
- stqs = p->sys_task_qs;
- if (!stqs->q[prio]) {
- stqs->q[prio] = st;
- stqs->qmask |= 1 << prio;
- }
- else {
- st->next = stqs->q[prio];
- st->prev = stqs->q[prio]->prev;
- st->next->prev = st;
- st->prev->next = st;
- ASSERT(stqs->qmask & (1 << prio));
- }
- }
-
- if (ERTS_PSFLGS_GET_ACT_PRIO(state) > prio) {
- erts_aint32_t n, a, e;
- /* Need to elevate actual prio */
-
- a = state;
- do {
- if (ERTS_PSFLGS_GET_ACT_PRIO(a) <= prio) {
- n = a;
- break;
- }
- n = e = a;
- n &= ~ERTS_PSFLGS_ACT_PRIO_MASK;
- n |= (prio << ERTS_PSFLGS_ACT_PRIO_OFFSET);
- a = erts_smp_atomic32_cmpxchg_nob(&p->state, n, e);
- } while (a != e);
- state = n;
- }
-
-
- a = state;
+ already_scheduled = 0;
+ status_locked = 0;
enq_prio = -1;
+ a = state;
- /* Status lock prevents out of order "runnable proc" trace msgs */
- ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_STATUS & erts_proc_lc_my_proc_locks(p));
+ ERTS_SMP_LC_ASSERT(!(ERTS_PROC_LOCK_STATUS & erts_proc_lc_my_proc_locks(p)));
+ ASSERT(fail_state & (ERTS_PSFLG_EXITING | ERTS_PSFLG_FREE));
+ ASSERT(!(fail_state & enable_flags));
+ ASSERT(!(state & ERTS_PSFLG_PROXY));
- if (!prof_runnable_procs) {
- erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
- locked = 0;
+ /* When runnable_procs is enabled, we need to take the status lock to
+ * prevent trace messages from being sent in the wrong order. The lock must
+ * be held over the call to add2runq.
+ *
+ * Otherwise, we only need to take it when we're enqueuing a task and can
+ * safely release it before add2runq. */
+ if (sys_task || runnable_procs) {
+ erts_smp_proc_lock(p, ERTS_PROC_LOCK_STATUS);
+ status_locked = 1;
}
- ASSERT(!(state & ERTS_PSFLG_PROXY));
-
while (1) {
erts_aint32_t e;
n = e = a;
- if (a & ERTS_PSFLG_FREE)
- goto cleanup; /* We don't want to schedule free processes... */
+ if (a & fail_state) {
+ *fail_state_p = a & fail_state;
+ goto cleanup;
+ }
enqueue = ERTS_ENQUEUE_NOT;
- n |= ERTS_PSFLG_ACTIVE_SYS;
+ n |= enable_flags;
+
if (!(a & (ERTS_PSFLG_RUNNING
| ERTS_PSFLG_RUNNING_SYS
| ERTS_PSFLG_DIRTY_RUNNING
- | ERTS_PSFLG_DIRTY_RUNNING_SYS)))
+ | ERTS_PSFLG_DIRTY_RUNNING_SYS))) {
enqueue = check_enqueue_in_prio_queue(p, &enq_prio, &n, a);
+ }
+
a = erts_smp_atomic32_cmpxchg_mb(&p->state, n, e);
- if (a == e)
+ if (a == e) {
break;
- if (a == n && enqueue == ERTS_ENQUEUE_NOT)
- goto cleanup;
+ }
+ else if (a == n && enqueue == ERTS_ENQUEUE_NOT) {
+ already_scheduled = 1;
+ break;
+ }
}
- if (prof_runnable_procs) {
-
+ if (!already_scheduled && runnable_procs) {
if (!(a & (ERTS_PSFLG_ACTIVE_SYS
| ERTS_PSFLG_RUNNING
| ERTS_PSFLG_RUNNING_SYS
@@ -7288,24 +7231,89 @@ schedule_process_sys_task(Process *p, erts_aint32_t prio, ErtsProcSysTask *st,
/* We activated a prevously inactive process */
profile_runnable_proc(p, am_active);
}
+ }
- erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
- locked = 0;
+ if (sys_task) {
+ ErtsProcSysTaskQs *stqs = p->sys_task_qs;
+
+ if (!stqs) {
+ sys_task->next = sys_task->prev = sys_task;
+
+ stqs = proc_sys_task_queues_alloc();
+
+ stqs->qmask = 1 << task_prio;
+ stqs->ncount = 0;
+ stqs->q[PRIORITY_MAX] = NULL;
+ stqs->q[PRIORITY_HIGH] = NULL;
+ stqs->q[PRIORITY_NORMAL] = NULL;
+ stqs->q[PRIORITY_LOW] = NULL;
+ stqs->q[task_prio] = sys_task;
+
+ p->sys_task_qs = stqs;
+ }
+ else {
+ if (!stqs->q[task_prio]) {
+ sys_task->next = sys_task->prev = sys_task;
+
+ stqs->q[task_prio] = sys_task;
+ stqs->qmask |= 1 << task_prio;
+ }
+ else {
+ sys_task->next = stqs->q[task_prio];
+ sys_task->prev = stqs->q[task_prio]->prev;
+ sys_task->next->prev = sys_task;
+ sys_task->prev->next = sys_task;
+ ASSERT(stqs->qmask & (1 << task_prio));
+ }
+ }
+ }
+
+ if (status_locked && !runnable_procs) {
+ erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
+ status_locked = 0;
}
- add2runq(enqueue, enq_prio, p, n, NULL);
+ if (!already_scheduled) {
+ add2runq(enqueue, enq_prio, p, n, NULL);
+ }
cleanup:
+ if (status_locked) {
+ erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
+ }
- if (locked)
- erts_smp_proc_unlock(p, ERTS_PROC_LOCK_STATUS);
+ return n;
+}
+
+static int
+schedule_process_sys_task(Process *p, erts_aint32_t prio, ErtsProcSysTask *st,
+ erts_aint32_t *fail_state_p)
+{
+ erts_aint32_t fail_state, state;
- if (free_stqs)
- proc_sys_task_queues_free(free_stqs);
+ /* Elevate priority if needed. */
+ state = erts_smp_atomic32_read_nob(&p->state);
+ if (ERTS_PSFLGS_GET_ACT_PRIO(state) > prio) {
+ erts_aint32_t n, a, e;
- ERTS_SMP_LC_ASSERT(!(ERTS_PROC_LOCK_STATUS & erts_proc_lc_my_proc_locks(p)));
+ a = state;
+ do {
+ if (ERTS_PSFLGS_GET_ACT_PRIO(a) <= prio) {
+ n = a;
+ break;
+ }
+ n = e = a;
+ n &= ~ERTS_PSFLGS_ACT_PRIO_MASK;
+ n |= (prio << ERTS_PSFLGS_ACT_PRIO_OFFSET);
+ a = erts_smp_atomic32_cmpxchg_nob(&p->state, n, e);
+ } while (a != e);
- return res;
+ state = n;
+ }
+
+ fail_state = *fail_state_p;
+
+ return !(active_sys_enqueue(p, st, prio, 0, state, fail_state_p) & fail_state);
}
static ERTS_INLINE int
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-11 06:22:27 +0000