-/* Copyright (C) 2007, 2008, 2009, 2011 Free Software Foundation, Inc.
+/* Copyright (C) 2007-2017 Free Software Foundation, Inc.
Contributed by Richard Henderson <rth@redhat.com>.
- This file is part of the GNU OpenMP Library (libgomp).
+ This file is part of the GNU Offloading and Multi Processing Library
+ (libgomp).
Libgomp is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by
#include "libgomp.h"
#include <stdlib.h>
#include <string.h>
+#include "gomp-constants.h"
+typedef struct gomp_task_depend_entry *hash_entry_type;
+
+static inline void *
+htab_alloc (size_t size)
+{
+ return gomp_malloc (size);
+}
+
+static inline void
+htab_free (void *ptr)
+{
+ free (ptr);
+}
+
+#include "hashtab.h"
+
+static inline hashval_t
+htab_hash (hash_entry_type element)
+{
+ return hash_pointer (element->addr);
+}
+
+static inline bool
+htab_eq (hash_entry_type x, hash_entry_type y)
+{
+ return x->addr == y->addr;
+}
/* Create a new task data structure. */
gomp_init_task (struct gomp_task *task, struct gomp_task *parent_task,
struct gomp_task_icv *prev_icv)
{
+ /* It would seem that using memset here would be a win, but it turns
+ out that partially filling gomp_task allows us to keep the
+ overhead of task creation low. In the nqueens-1.c test, for a
+ sufficiently large N, we drop the overhead from 5-6% to 1%.
+
+ Note, the nqueens-1.c test in serial mode is a good test to
+ benchmark the overhead of creating tasks as there are millions of
+ tiny tasks created that all run undeferred. */
task->parent = parent_task;
task->icv = *prev_icv;
task->kind = GOMP_TASK_IMPLICIT;
- task->in_taskwait = false;
+ task->taskwait = NULL;
task->in_tied_task = false;
task->final_task = false;
- task->children = NULL;
- gomp_sem_init (&task->taskwait_sem, 0);
+ task->copy_ctors_done = false;
+ task->parent_depends_on = false;
+ priority_queue_init (&task->children_queue);
+ task->taskgroup = NULL;
+ task->dependers = NULL;
+ task->depend_hash = NULL;
+ task->depend_count = 0;
}
/* Clean up a task, after completing it. */
thr->task = task->parent;
}
+/* Clear the parent field of every task in LIST. */
+
static inline void
-gomp_clear_parent (struct gomp_task *children)
+gomp_clear_parent_in_list (struct priority_list *list)
{
- struct gomp_task *task = children;
-
- if (task)
+ struct priority_node *p = list->tasks;
+ if (p)
do
{
- task->parent = NULL;
- task = task->next_child;
+ priority_node_to_task (PQ_CHILDREN, p)->parent = NULL;
+ p = p->next;
}
- while (task != children);
+ while (p != list->tasks);
+}
+
+/* Splay tree version of gomp_clear_parent_in_list.
+
+ Clear the parent field of every task in NODE within SP, and free
+ the node when done. */
+
+static void
+gomp_clear_parent_in_tree (prio_splay_tree sp, prio_splay_tree_node node)
+{
+ if (!node)
+ return;
+ prio_splay_tree_node left = node->left, right = node->right;
+ gomp_clear_parent_in_list (&node->key.l);
+#if _LIBGOMP_CHECKING_
+ memset (node, 0xaf, sizeof (*node));
+#endif
+ /* No need to remove the node from the tree. We're nuking
+ everything, so just free the nodes and our caller can clear the
+ entire splay tree. */
+ free (node);
+ gomp_clear_parent_in_tree (sp, left);
+ gomp_clear_parent_in_tree (sp, right);
+}
+
+/* Clear the parent field of every task in Q and remove every task
+ from Q. */
+
+static inline void
+gomp_clear_parent (struct priority_queue *q)
+{
+ if (priority_queue_multi_p (q))
+ {
+ gomp_clear_parent_in_tree (&q->t, q->t.root);
+ /* All the nodes have been cleared in gomp_clear_parent_in_tree.
+ No need to remove anything. We can just nuke everything. */
+ q->t.root = NULL;
+ }
+ else
+ gomp_clear_parent_in_list (&q->l);
+}
+
+/* Helper function for GOMP_task and gomp_create_target_task.
+
+ For a TASK with in/out dependencies, fill in the various dependency
+ queues. PARENT is the parent of said task. DEPEND is as in
+ GOMP_task. */
+
+static void
+gomp_task_handle_depend (struct gomp_task *task, struct gomp_task *parent,
+ void **depend)
+{
+ size_t ndepend = (uintptr_t) depend[0];
+ size_t nout = (uintptr_t) depend[1];
+ size_t i;
+ hash_entry_type ent;
+
+ task->depend_count = ndepend;
+ task->num_dependees = 0;
+ if (parent->depend_hash == NULL)
+ parent->depend_hash = htab_create (2 * ndepend > 12 ? 2 * ndepend : 12);
+ for (i = 0; i < ndepend; i++)
+ {
+ task->depend[i].addr = depend[2 + i];
+ task->depend[i].next = NULL;
+ task->depend[i].prev = NULL;
+ task->depend[i].task = task;
+ task->depend[i].is_in = i >= nout;
+ task->depend[i].redundant = false;
+ task->depend[i].redundant_out = false;
+
+ hash_entry_type *slot = htab_find_slot (&parent->depend_hash,
+ &task->depend[i], INSERT);
+ hash_entry_type out = NULL, last = NULL;
+ if (*slot)
+ {
+ /* If multiple depends on the same task are the same, all but the
+ first one are redundant. As inout/out come first, if any of them
+ is inout/out, it will win, which is the right semantics. */
+ if ((*slot)->task == task)
+ {
+ task->depend[i].redundant = true;
+ continue;
+ }
+ for (ent = *slot; ent; ent = ent->next)
+ {
+ if (ent->redundant_out)
+ break;
+
+ last = ent;
+
+ /* depend(in:...) doesn't depend on earlier depend(in:...). */
+ if (i >= nout && ent->is_in)
+ continue;
+
+ if (!ent->is_in)
+ out = ent;
+
+ struct gomp_task *tsk = ent->task;
+ if (tsk->dependers == NULL)
+ {
+ tsk->dependers
+ = gomp_malloc (sizeof (struct gomp_dependers_vec)
+ + 6 * sizeof (struct gomp_task *));
+ tsk->dependers->n_elem = 1;
+ tsk->dependers->allocated = 6;
+ tsk->dependers->elem[0] = task;
+ task->num_dependees++;
+ continue;
+ }
+ /* We already have some other dependency on tsk from earlier
+ depend clause. */
+ else if (tsk->dependers->n_elem
+ && (tsk->dependers->elem[tsk->dependers->n_elem - 1]
+ == task))
+ continue;
+ else if (tsk->dependers->n_elem == tsk->dependers->allocated)
+ {
+ tsk->dependers->allocated
+ = tsk->dependers->allocated * 2 + 2;
+ tsk->dependers
+ = gomp_realloc (tsk->dependers,
+ sizeof (struct gomp_dependers_vec)
+ + (tsk->dependers->allocated
+ * sizeof (struct gomp_task *)));
+ }
+ tsk->dependers->elem[tsk->dependers->n_elem++] = task;
+ task->num_dependees++;
+ }
+ task->depend[i].next = *slot;
+ (*slot)->prev = &task->depend[i];
+ }
+ *slot = &task->depend[i];
+
+ /* There is no need to store more than one depend({,in}out:) task per
+ address in the hash table chain for the purpose of creation of
+ deferred tasks, because each out depends on all earlier outs, thus it
+ is enough to record just the last depend({,in}out:). For depend(in:),
+ we need to keep all of the previous ones not terminated yet, because
+ a later depend({,in}out:) might need to depend on all of them. So, if
+ the new task's clause is depend({,in}out:), we know there is at most
+ one other depend({,in}out:) clause in the list (out). For
+ non-deferred tasks we want to see all outs, so they are moved to the
+ end of the chain, after first redundant_out entry all following
+ entries should be redundant_out. */
+ if (!task->depend[i].is_in && out)
+ {
+ if (out != last)
+ {
+ out->next->prev = out->prev;
+ out->prev->next = out->next;
+ out->next = last->next;
+ out->prev = last;
+ last->next = out;
+ if (out->next)
+ out->next->prev = out;
+ }
+ out->redundant_out = true;
+ }
+ }
}
/* Called when encountering an explicit task directive. If IF_CLAUSE is
false, then we must not delay in executing the task. If UNTIED is true,
- then the task may be executed by any member of the team. */
+ then the task may be executed by any member of the team.
+
+ DEPEND is an array containing:
+ depend[0]: number of depend elements.
+ depend[1]: number of depend elements of type "out".
+ depend[2..N+1]: address of [1..N]th depend element. */
void
GOMP_task (void (*fn) (void *), void *data, void (*cpyfn) (void *, void *),
- long arg_size, long arg_align, bool if_clause, unsigned flags)
+ long arg_size, long arg_align, bool if_clause, unsigned flags,
+ void **depend, int priority)
{
struct gomp_thread *thr = gomp_thread ();
struct gomp_team *team = thr->ts.team;
might be running on different thread than FN. */
if (cpyfn)
if_clause = false;
- if (flags & 1)
- flags &= ~1;
+ flags &= ~GOMP_TASK_FLAG_UNTIED;
#endif
+ /* If parallel or taskgroup has been cancelled, don't start new tasks. */
+ if (team
+ && (gomp_team_barrier_cancelled (&team->barrier)
+ || (thr->task->taskgroup && thr->task->taskgroup->cancelled)))
+ return;
+
+ if ((flags & GOMP_TASK_FLAG_PRIORITY) == 0)
+ priority = 0;
+ else if (priority > gomp_max_task_priority_var)
+ priority = gomp_max_task_priority_var;
+
if (!if_clause || team == NULL
|| (thr->task && thr->task->final_task)
|| team->task_count > 64 * team->nthreads)
{
struct gomp_task task;
+ /* If there are depend clauses and earlier deferred sibling tasks
+ with depend clauses, check if there isn't a dependency. If there
+ is, we need to wait for them. There is no need to handle
+ depend clauses for non-deferred tasks other than this, because
+ the parent task is suspended until the child task finishes and thus
+ it can't start further child tasks. */
+ if ((flags & GOMP_TASK_FLAG_DEPEND)
+ && thr->task && thr->task->depend_hash)
+ gomp_task_maybe_wait_for_dependencies (depend);
+
gomp_init_task (&task, thr->task, gomp_icv (false));
- task.kind = GOMP_TASK_IFFALSE;
- task.final_task = (thr->task && thr->task->final_task) || (flags & 2);
+ task.kind = GOMP_TASK_UNDEFERRED;
+ task.final_task = (thr->task && thr->task->final_task)
+ || (flags & GOMP_TASK_FLAG_FINAL);
+ task.priority = priority;
if (thr->task)
- task.in_tied_task = thr->task->in_tied_task;
+ {
+ task.in_tied_task = thr->task->in_tied_task;
+ task.taskgroup = thr->task->taskgroup;
+ }
thr->task = &task;
if (__builtin_expect (cpyfn != NULL, 0))
{
}
else
fn (data);
- if (task.children)
+ /* Access to "children" is normally done inside a task_lock
+ mutex region, but the only way this particular task.children
+ can be set is if this thread's task work function (fn)
+ creates children. So since the setter is *this* thread, we
+ need no barriers here when testing for non-NULL. We can have
+ task.children set by the current thread then changed by a
+ child thread, but seeing a stale non-NULL value is not a
+ problem. Once past the task_lock acquisition, this thread
+ will see the real value of task.children. */
+ if (!priority_queue_empty_p (&task.children_queue, MEMMODEL_RELAXED))
{
gomp_mutex_lock (&team->task_lock);
- gomp_clear_parent (task.children);
+ gomp_clear_parent (&task.children_queue);
gomp_mutex_unlock (&team->task_lock);
}
gomp_end_task ();
{
struct gomp_task *task;
struct gomp_task *parent = thr->task;
+ struct gomp_taskgroup *taskgroup = parent->taskgroup;
char *arg;
bool do_wake;
+ size_t depend_size = 0;
- task = gomp_malloc (sizeof (*task) + arg_size + arg_align - 1);
- arg = (char *) (((uintptr_t) (task + 1) + arg_align - 1)
+ if (flags & GOMP_TASK_FLAG_DEPEND)
+ depend_size = ((uintptr_t) depend[0]
+ * sizeof (struct gomp_task_depend_entry));
+ task = gomp_malloc (sizeof (*task) + depend_size
+ + arg_size + arg_align - 1);
+ arg = (char *) (((uintptr_t) (task + 1) + depend_size + arg_align - 1)
& ~(uintptr_t) (arg_align - 1));
gomp_init_task (task, parent, gomp_icv (false));
- task->kind = GOMP_TASK_IFFALSE;
+ task->priority = priority;
+ task->kind = GOMP_TASK_UNDEFERRED;
task->in_tied_task = parent->in_tied_task;
+ task->taskgroup = taskgroup;
thr->task = task;
if (cpyfn)
- cpyfn (arg, data);
+ {
+ cpyfn (arg, data);
+ task->copy_ctors_done = true;
+ }
else
memcpy (arg, data, arg_size);
thr->task = parent;
task->kind = GOMP_TASK_WAITING;
task->fn = fn;
task->fn_data = arg;
- task->in_tied_task = true;
- task->final_task = (flags & 2) >> 1;
+ task->final_task = (flags & GOMP_TASK_FLAG_FINAL) >> 1;
gomp_mutex_lock (&team->task_lock);
- if (parent->children)
- {
- task->next_child = parent->children;
- task->prev_child = parent->children->prev_child;
- task->next_child->prev_child = task;
- task->prev_child->next_child = task;
- }
- else
- {
- task->next_child = task;
- task->prev_child = task;
- }
- parent->children = task;
- if (team->task_queue)
+ /* If parallel or taskgroup has been cancelled, don't start new
+ tasks. */
+ if (__builtin_expect ((gomp_team_barrier_cancelled (&team->barrier)
+ || (taskgroup && taskgroup->cancelled))
+ && !task->copy_ctors_done, 0))
{
- task->next_queue = team->task_queue;
- task->prev_queue = team->task_queue->prev_queue;
- task->next_queue->prev_queue = task;
- task->prev_queue->next_queue = task;
+ gomp_mutex_unlock (&team->task_lock);
+ gomp_finish_task (task);
+ free (task);
+ return;
}
- else
+ if (taskgroup)
+ taskgroup->num_children++;
+ if (depend_size)
{
- task->next_queue = task;
- task->prev_queue = task;
- team->task_queue = task;
+ gomp_task_handle_depend (task, parent, depend);
+ if (task->num_dependees)
+ {
+ /* Tasks that depend on other tasks are not put into the
+ various waiting queues, so we are done for now. Said
+ tasks are instead put into the queues via
+ gomp_task_run_post_handle_dependers() after their
+ dependencies have been satisfied. After which, they
+ can be picked up by the various scheduling
+ points. */
+ gomp_mutex_unlock (&team->task_lock);
+ return;
+ }
}
+
+ priority_queue_insert (PQ_CHILDREN, &parent->children_queue,
+ task, priority,
+ PRIORITY_INSERT_BEGIN,
+ /*adjust_parent_depends_on=*/false,
+ task->parent_depends_on);
+ if (taskgroup)
+ priority_queue_insert (PQ_TASKGROUP, &taskgroup->taskgroup_queue,
+ task, priority,
+ PRIORITY_INSERT_BEGIN,
+ /*adjust_parent_depends_on=*/false,
+ task->parent_depends_on);
+
+ priority_queue_insert (PQ_TEAM, &team->task_queue,
+ task, priority,
+ PRIORITY_INSERT_END,
+ /*adjust_parent_depends_on=*/false,
+ task->parent_depends_on);
+
++team->task_count;
+ ++team->task_queued_count;
gomp_team_barrier_set_task_pending (&team->barrier);
do_wake = team->task_running_count + !parent->in_tied_task
< team->nthreads;
}
}
+ialias (GOMP_taskgroup_start)
+ialias (GOMP_taskgroup_end)
+
+#define TYPE long
+#define UTYPE unsigned long
+#define TYPE_is_long 1
+#include "taskloop.c"
+#undef TYPE
+#undef UTYPE
+#undef TYPE_is_long
+
+#define TYPE unsigned long long
+#define UTYPE TYPE
+#define GOMP_taskloop GOMP_taskloop_ull
+#include "taskloop.c"
+#undef TYPE
+#undef UTYPE
+#undef GOMP_taskloop
+
+static void inline
+priority_queue_move_task_first (enum priority_queue_type type,
+ struct priority_queue *head,
+ struct gomp_task *task)
+{
+#if _LIBGOMP_CHECKING_
+ if (!priority_queue_task_in_queue_p (type, head, task))
+ gomp_fatal ("Attempt to move first missing task %p", task);
+#endif
+ struct priority_list *list;
+ if (priority_queue_multi_p (head))
+ {
+ list = priority_queue_lookup_priority (head, task->priority);
+#if _LIBGOMP_CHECKING_
+ if (!list)
+ gomp_fatal ("Unable to find priority %d", task->priority);
+#endif
+ }
+ else
+ list = &head->l;
+ priority_list_remove (list, task_to_priority_node (type, task), 0);
+ priority_list_insert (type, list, task, task->priority,
+ PRIORITY_INSERT_BEGIN, type == PQ_CHILDREN,
+ task->parent_depends_on);
+}
+
+/* Actual body of GOMP_PLUGIN_target_task_completion that is executed
+ with team->task_lock held, or is executed in the thread that called
+ gomp_target_task_fn if GOMP_PLUGIN_target_task_completion has been
+ run before it acquires team->task_lock. */
+
+static void
+gomp_target_task_completion (struct gomp_team *team, struct gomp_task *task)
+{
+ struct gomp_task *parent = task->parent;
+ if (parent)
+ priority_queue_move_task_first (PQ_CHILDREN, &parent->children_queue,
+ task);
+
+ struct gomp_taskgroup *taskgroup = task->taskgroup;
+ if (taskgroup)
+ priority_queue_move_task_first (PQ_TASKGROUP, &taskgroup->taskgroup_queue,
+ task);
+
+ priority_queue_insert (PQ_TEAM, &team->task_queue, task, task->priority,
+ PRIORITY_INSERT_BEGIN, false,
+ task->parent_depends_on);
+ task->kind = GOMP_TASK_WAITING;
+ if (parent && parent->taskwait)
+ {
+ if (parent->taskwait->in_taskwait)
+ {
+ /* One more task has had its dependencies met.
+ Inform any waiters. */
+ parent->taskwait->in_taskwait = false;
+ gomp_sem_post (&parent->taskwait->taskwait_sem);
+ }
+ else if (parent->taskwait->in_depend_wait)
+ {
+ /* One more task has had its dependencies met.
+ Inform any waiters. */
+ parent->taskwait->in_depend_wait = false;
+ gomp_sem_post (&parent->taskwait->taskwait_sem);
+ }
+ }
+ if (taskgroup && taskgroup->in_taskgroup_wait)
+ {
+ /* One more task has had its dependencies met.
+ Inform any waiters. */
+ taskgroup->in_taskgroup_wait = false;
+ gomp_sem_post (&taskgroup->taskgroup_sem);
+ }
+
+ ++team->task_queued_count;
+ gomp_team_barrier_set_task_pending (&team->barrier);
+ /* I'm afraid this can't be done after releasing team->task_lock,
+ as gomp_target_task_completion is run from unrelated thread and
+ therefore in between gomp_mutex_unlock and gomp_team_barrier_wake
+ the team could be gone already. */
+ if (team->nthreads > team->task_running_count)
+ gomp_team_barrier_wake (&team->barrier, 1);
+}
+
+/* Signal that a target task TTASK has completed the asynchronously
+ running phase and should be requeued as a task to handle the
+ variable unmapping. */
+
+void
+GOMP_PLUGIN_target_task_completion (void *data)
+{
+ struct gomp_target_task *ttask = (struct gomp_target_task *) data;
+ struct gomp_task *task = ttask->task;
+ struct gomp_team *team = ttask->team;
+
+ gomp_mutex_lock (&team->task_lock);
+ if (ttask->state == GOMP_TARGET_TASK_READY_TO_RUN)
+ {
+ ttask->state = GOMP_TARGET_TASK_FINISHED;
+ gomp_mutex_unlock (&team->task_lock);
+ return;
+ }
+ ttask->state = GOMP_TARGET_TASK_FINISHED;
+ gomp_target_task_completion (team, task);
+ gomp_mutex_unlock (&team->task_lock);
+}
+
+static void gomp_task_run_post_handle_depend_hash (struct gomp_task *);
+
+/* Called for nowait target tasks. */
+
+bool
+gomp_create_target_task (struct gomp_device_descr *devicep,
+ void (*fn) (void *), size_t mapnum, void **hostaddrs,
+ size_t *sizes, unsigned short *kinds,
+ unsigned int flags, void **depend, void **args,
+ enum gomp_target_task_state state)
+{
+ struct gomp_thread *thr = gomp_thread ();
+ struct gomp_team *team = thr->ts.team;
+
+ /* If parallel or taskgroup has been cancelled, don't start new tasks. */
+ if (team
+ && (gomp_team_barrier_cancelled (&team->barrier)
+ || (thr->task->taskgroup && thr->task->taskgroup->cancelled)))
+ return true;
+
+ struct gomp_target_task *ttask;
+ struct gomp_task *task;
+ struct gomp_task *parent = thr->task;
+ struct gomp_taskgroup *taskgroup = parent->taskgroup;
+ bool do_wake;
+ size_t depend_size = 0;
+ uintptr_t depend_cnt = 0;
+ size_t tgt_align = 0, tgt_size = 0;
+
+ if (depend != NULL)
+ {
+ depend_cnt = (uintptr_t) depend[0];
+ depend_size = depend_cnt * sizeof (struct gomp_task_depend_entry);
+ }
+ if (fn)
+ {
+ /* GOMP_MAP_FIRSTPRIVATE need to be copied first, as they are
+ firstprivate on the target task. */
+ size_t i;
+ for (i = 0; i < mapnum; i++)
+ if ((kinds[i] & 0xff) == GOMP_MAP_FIRSTPRIVATE)
+ {
+ size_t align = (size_t) 1 << (kinds[i] >> 8);
+ if (tgt_align < align)
+ tgt_align = align;
+ tgt_size = (tgt_size + align - 1) & ~(align - 1);
+ tgt_size += sizes[i];
+ }
+ if (tgt_align)
+ tgt_size += tgt_align - 1;
+ else
+ tgt_size = 0;
+ }
+
+ task = gomp_malloc (sizeof (*task) + depend_size
+ + sizeof (*ttask)
+ + mapnum * (sizeof (void *) + sizeof (size_t)
+ + sizeof (unsigned short))
+ + tgt_size);
+ gomp_init_task (task, parent, gomp_icv (false));
+ task->priority = 0;
+ task->kind = GOMP_TASK_WAITING;
+ task->in_tied_task = parent->in_tied_task;
+ task->taskgroup = taskgroup;
+ ttask = (struct gomp_target_task *) &task->depend[depend_cnt];
+ ttask->devicep = devicep;
+ ttask->fn = fn;
+ ttask->mapnum = mapnum;
+ ttask->args = args;
+ memcpy (ttask->hostaddrs, hostaddrs, mapnum * sizeof (void *));
+ ttask->sizes = (size_t *) &ttask->hostaddrs[mapnum];
+ memcpy (ttask->sizes, sizes, mapnum * sizeof (size_t));
+ ttask->kinds = (unsigned short *) &ttask->sizes[mapnum];
+ memcpy (ttask->kinds, kinds, mapnum * sizeof (unsigned short));
+ if (tgt_align)
+ {
+ char *tgt = (char *) &ttask->kinds[mapnum];
+ size_t i;
+ uintptr_t al = (uintptr_t) tgt & (tgt_align - 1);
+ if (al)
+ tgt += tgt_align - al;
+ tgt_size = 0;
+ for (i = 0; i < mapnum; i++)
+ if ((kinds[i] & 0xff) == GOMP_MAP_FIRSTPRIVATE)
+ {
+ size_t align = (size_t) 1 << (kinds[i] >> 8);
+ tgt_size = (tgt_size + align - 1) & ~(align - 1);
+ memcpy (tgt + tgt_size, hostaddrs[i], sizes[i]);
+ ttask->hostaddrs[i] = tgt + tgt_size;
+ tgt_size = tgt_size + sizes[i];
+ }
+ }
+ ttask->flags = flags;
+ ttask->state = state;
+ ttask->task = task;
+ ttask->team = team;
+ task->fn = NULL;
+ task->fn_data = ttask;
+ task->final_task = 0;
+ gomp_mutex_lock (&team->task_lock);
+ /* If parallel or taskgroup has been cancelled, don't start new tasks. */
+ if (__builtin_expect (gomp_team_barrier_cancelled (&team->barrier)
+ || (taskgroup && taskgroup->cancelled), 0))
+ {
+ gomp_mutex_unlock (&team->task_lock);
+ gomp_finish_task (task);
+ free (task);
+ return true;
+ }
+ if (depend_size)
+ {
+ gomp_task_handle_depend (task, parent, depend);
+ if (task->num_dependees)
+ {
+ if (taskgroup)
+ taskgroup->num_children++;
+ gomp_mutex_unlock (&team->task_lock);
+ return true;
+ }
+ }
+ if (state == GOMP_TARGET_TASK_DATA)
+ {
+ gomp_task_run_post_handle_depend_hash (task);
+ gomp_mutex_unlock (&team->task_lock);
+ gomp_finish_task (task);
+ free (task);
+ return false;
+ }
+ if (taskgroup)
+ taskgroup->num_children++;
+ /* For async offloading, if we don't need to wait for dependencies,
+ run the gomp_target_task_fn right away, essentially schedule the
+ mapping part of the task in the current thread. */
+ if (devicep != NULL
+ && (devicep->capabilities & GOMP_OFFLOAD_CAP_OPENMP_400))
+ {
+ priority_queue_insert (PQ_CHILDREN, &parent->children_queue, task, 0,
+ PRIORITY_INSERT_END,
+ /*adjust_parent_depends_on=*/false,
+ task->parent_depends_on);
+ if (taskgroup)
+ priority_queue_insert (PQ_TASKGROUP, &taskgroup->taskgroup_queue,
+ task, 0, PRIORITY_INSERT_END,
+ /*adjust_parent_depends_on=*/false,
+ task->parent_depends_on);
+ task->pnode[PQ_TEAM].next = NULL;
+ task->pnode[PQ_TEAM].prev = NULL;
+ task->kind = GOMP_TASK_TIED;
+ ++team->task_count;
+ gomp_mutex_unlock (&team->task_lock);
+
+ thr->task = task;
+ gomp_target_task_fn (task->fn_data);
+ thr->task = parent;
+
+ gomp_mutex_lock (&team->task_lock);
+ task->kind = GOMP_TASK_ASYNC_RUNNING;
+ /* If GOMP_PLUGIN_target_task_completion has run already
+ in between gomp_target_task_fn and the mutex lock,
+ perform the requeuing here. */
+ if (ttask->state == GOMP_TARGET_TASK_FINISHED)
+ gomp_target_task_completion (team, task);
+ else
+ ttask->state = GOMP_TARGET_TASK_RUNNING;
+ gomp_mutex_unlock (&team->task_lock);
+ return true;
+ }
+ priority_queue_insert (PQ_CHILDREN, &parent->children_queue, task, 0,
+ PRIORITY_INSERT_BEGIN,
+ /*adjust_parent_depends_on=*/false,
+ task->parent_depends_on);
+ if (taskgroup)
+ priority_queue_insert (PQ_TASKGROUP, &taskgroup->taskgroup_queue, task, 0,
+ PRIORITY_INSERT_BEGIN,
+ /*adjust_parent_depends_on=*/false,
+ task->parent_depends_on);
+ priority_queue_insert (PQ_TEAM, &team->task_queue, task, 0,
+ PRIORITY_INSERT_END,
+ /*adjust_parent_depends_on=*/false,
+ task->parent_depends_on);
+ ++team->task_count;
+ ++team->task_queued_count;
+ gomp_team_barrier_set_task_pending (&team->barrier);
+ do_wake = team->task_running_count + !parent->in_tied_task
+ < team->nthreads;
+ gomp_mutex_unlock (&team->task_lock);
+ if (do_wake)
+ gomp_team_barrier_wake (&team->barrier, 1);
+ return true;
+}
+
+/* Given a parent_depends_on task in LIST, move it to the front of its
+ priority so it is run as soon as possible.
+
+ Care is taken to update the list's LAST_PARENT_DEPENDS_ON field.
+
+ We rearrange the queue such that all parent_depends_on tasks are
+ first, and last_parent_depends_on points to the last such task we
+ rearranged. For example, given the following tasks in a queue
+ where PD[123] are the parent_depends_on tasks:
+
+ task->children
+ |
+ V
+ C1 -> C2 -> C3 -> PD1 -> PD2 -> PD3 -> C4
+
+ We rearrange such that:
+
+ task->children
+ | +--- last_parent_depends_on
+ | |
+ V V
+ PD1 -> PD2 -> PD3 -> C1 -> C2 -> C3 -> C4. */
+
+static void inline
+priority_list_upgrade_task (struct priority_list *list,
+ struct priority_node *node)
+{
+ struct priority_node *last_parent_depends_on
+ = list->last_parent_depends_on;
+ if (last_parent_depends_on)
+ {
+ node->prev->next = node->next;
+ node->next->prev = node->prev;
+ node->prev = last_parent_depends_on;
+ node->next = last_parent_depends_on->next;
+ node->prev->next = node;
+ node->next->prev = node;
+ }
+ else if (node != list->tasks)
+ {
+ node->prev->next = node->next;
+ node->next->prev = node->prev;
+ node->prev = list->tasks->prev;
+ node->next = list->tasks;
+ list->tasks = node;
+ node->prev->next = node;
+ node->next->prev = node;
+ }
+ list->last_parent_depends_on = node;
+}
+
+/* Given a parent_depends_on TASK in its parent's children_queue, move
+ it to the front of its priority so it is run as soon as possible.
+
+ PARENT is passed as an optimization.
+
+ (This function could be defined in priority_queue.c, but we want it
+ inlined, and putting it in priority_queue.h is not an option, given
+ that gomp_task has not been properly defined at that point). */
+
+static void inline
+priority_queue_upgrade_task (struct gomp_task *task,
+ struct gomp_task *parent)
+{
+ struct priority_queue *head = &parent->children_queue;
+ struct priority_node *node = &task->pnode[PQ_CHILDREN];
+#if _LIBGOMP_CHECKING_
+ if (!task->parent_depends_on)
+ gomp_fatal ("priority_queue_upgrade_task: task must be a "
+ "parent_depends_on task");
+ if (!priority_queue_task_in_queue_p (PQ_CHILDREN, head, task))
+ gomp_fatal ("priority_queue_upgrade_task: cannot find task=%p", task);
+#endif
+ if (priority_queue_multi_p (head))
+ {
+ struct priority_list *list
+ = priority_queue_lookup_priority (head, task->priority);
+ priority_list_upgrade_task (list, node);
+ }
+ else
+ priority_list_upgrade_task (&head->l, node);
+}
+
+/* Given a CHILD_TASK in LIST that is about to be executed, move it out of
+ the way in LIST so that other tasks can be considered for
+ execution. LIST contains tasks of type TYPE.
+
+ Care is taken to update the queue's LAST_PARENT_DEPENDS_ON field
+ if applicable. */
+
+static void inline
+priority_list_downgrade_task (enum priority_queue_type type,
+ struct priority_list *list,
+ struct gomp_task *child_task)
+{
+ struct priority_node *node = task_to_priority_node (type, child_task);
+ if (list->tasks == node)
+ list->tasks = node->next;
+ else if (node->next != list->tasks)
+ {
+ /* The task in NODE is about to become TIED and TIED tasks
+ cannot come before WAITING tasks. If we're about to
+ leave the queue in such an indeterminate state, rewire
+ things appropriately. However, a TIED task at the end is
+ perfectly fine. */
+ struct gomp_task *next_task = priority_node_to_task (type, node->next);
+ if (next_task->kind == GOMP_TASK_WAITING)
+ {
+ /* Remove from list. */
+ node->prev->next = node->next;
+ node->next->prev = node->prev;
+ /* Rewire at the end. */
+ node->next = list->tasks;
+ node->prev = list->tasks->prev;
+ list->tasks->prev->next = node;
+ list->tasks->prev = node;
+ }
+ }
+
+ /* If the current task is the last_parent_depends_on for its
+ priority, adjust last_parent_depends_on appropriately. */
+ if (__builtin_expect (child_task->parent_depends_on, 0)
+ && list->last_parent_depends_on == node)
+ {
+ struct gomp_task *prev_child = priority_node_to_task (type, node->prev);
+ if (node->prev != node
+ && prev_child->kind == GOMP_TASK_WAITING
+ && prev_child->parent_depends_on)
+ list->last_parent_depends_on = node->prev;
+ else
+ {
+ /* There are no more parent_depends_on entries waiting
+ to run, clear the list. */
+ list->last_parent_depends_on = NULL;
+ }
+ }
+}
+
+/* Given a TASK in HEAD that is about to be executed, move it out of
+ the way so that other tasks can be considered for execution. HEAD
+ contains tasks of type TYPE.
+
+ Care is taken to update the queue's LAST_PARENT_DEPENDS_ON field
+ if applicable.
+
+ (This function could be defined in priority_queue.c, but we want it
+ inlined, and putting it in priority_queue.h is not an option, given
+ that gomp_task has not been properly defined at that point). */
+
+static void inline
+priority_queue_downgrade_task (enum priority_queue_type type,
+ struct priority_queue *head,
+ struct gomp_task *task)
+{
+#if _LIBGOMP_CHECKING_
+ if (!priority_queue_task_in_queue_p (type, head, task))
+ gomp_fatal ("Attempt to downgrade missing task %p", task);
+#endif
+ if (priority_queue_multi_p (head))
+ {
+ struct priority_list *list
+ = priority_queue_lookup_priority (head, task->priority);
+ priority_list_downgrade_task (type, list, task);
+ }
+ else
+ priority_list_downgrade_task (type, &head->l, task);
+}
+
+/* Setup CHILD_TASK to execute. This is done by setting the task to
+ TIED, and updating all relevant queues so that CHILD_TASK is no
+ longer chosen for scheduling. Also, remove CHILD_TASK from the
+ overall team task queue entirely.
+
+ Return TRUE if task or its containing taskgroup has been
+ cancelled. */
+
+static inline bool
+gomp_task_run_pre (struct gomp_task *child_task, struct gomp_task *parent,
+ struct gomp_team *team)
+{
+#if _LIBGOMP_CHECKING_
+ if (child_task->parent)
+ priority_queue_verify (PQ_CHILDREN,
+ &child_task->parent->children_queue, true);
+ if (child_task->taskgroup)
+ priority_queue_verify (PQ_TASKGROUP,
+ &child_task->taskgroup->taskgroup_queue, false);
+ priority_queue_verify (PQ_TEAM, &team->task_queue, false);
+#endif
+
+ /* Task is about to go tied, move it out of the way. */
+ if (parent)
+ priority_queue_downgrade_task (PQ_CHILDREN, &parent->children_queue,
+ child_task);
+
+ /* Task is about to go tied, move it out of the way. */
+ struct gomp_taskgroup *taskgroup = child_task->taskgroup;
+ if (taskgroup)
+ priority_queue_downgrade_task (PQ_TASKGROUP, &taskgroup->taskgroup_queue,
+ child_task);
+
+ priority_queue_remove (PQ_TEAM, &team->task_queue, child_task,
+ MEMMODEL_RELAXED);
+ child_task->pnode[PQ_TEAM].next = NULL;
+ child_task->pnode[PQ_TEAM].prev = NULL;
+ child_task->kind = GOMP_TASK_TIED;
+
+ if (--team->task_queued_count == 0)
+ gomp_team_barrier_clear_task_pending (&team->barrier);
+ if ((gomp_team_barrier_cancelled (&team->barrier)
+ || (taskgroup && taskgroup->cancelled))
+ && !child_task->copy_ctors_done)
+ return true;
+ return false;
+}
+
+static void
+gomp_task_run_post_handle_depend_hash (struct gomp_task *child_task)
+{
+ struct gomp_task *parent = child_task->parent;
+ size_t i;
+
+ for (i = 0; i < child_task->depend_count; i++)
+ if (!child_task->depend[i].redundant)
+ {
+ if (child_task->depend[i].next)
+ child_task->depend[i].next->prev = child_task->depend[i].prev;
+ if (child_task->depend[i].prev)
+ child_task->depend[i].prev->next = child_task->depend[i].next;
+ else
+ {
+ hash_entry_type *slot
+ = htab_find_slot (&parent->depend_hash, &child_task->depend[i],
+ NO_INSERT);
+ if (*slot != &child_task->depend[i])
+ abort ();
+ if (child_task->depend[i].next)
+ *slot = child_task->depend[i].next;
+ else
+ htab_clear_slot (parent->depend_hash, slot);
+ }
+ }
+}
+
+/* After a CHILD_TASK has been run, adjust the dependency queue for
+ each task that depends on CHILD_TASK, to record the fact that there
+ is one less dependency to worry about. If a task that depended on
+ CHILD_TASK now has no dependencies, place it in the various queues
+ so it gets scheduled to run.
+
+ TEAM is the team to which CHILD_TASK belongs to. */
+
+static size_t
+gomp_task_run_post_handle_dependers (struct gomp_task *child_task,
+ struct gomp_team *team)
+{
+ struct gomp_task *parent = child_task->parent;
+ size_t i, count = child_task->dependers->n_elem, ret = 0;
+ for (i = 0; i < count; i++)
+ {
+ struct gomp_task *task = child_task->dependers->elem[i];
+
+ /* CHILD_TASK satisfies a dependency for TASK. Keep track of
+ TASK's remaining dependencies. Once TASK has no other
+ depenencies, put it into the various queues so it will get
+ scheduled for execution. */
+ if (--task->num_dependees != 0)
+ continue;
+
+ struct gomp_taskgroup *taskgroup = task->taskgroup;
+ if (parent)
+ {
+ priority_queue_insert (PQ_CHILDREN, &parent->children_queue,
+ task, task->priority,
+ PRIORITY_INSERT_BEGIN,
+ /*adjust_parent_depends_on=*/true,
+ task->parent_depends_on);
+ if (parent->taskwait)
+ {
+ if (parent->taskwait->in_taskwait)
+ {
+ /* One more task has had its dependencies met.
+ Inform any waiters. */
+ parent->taskwait->in_taskwait = false;
+ gomp_sem_post (&parent->taskwait->taskwait_sem);
+ }
+ else if (parent->taskwait->in_depend_wait)
+ {
+ /* One more task has had its dependencies met.
+ Inform any waiters. */
+ parent->taskwait->in_depend_wait = false;
+ gomp_sem_post (&parent->taskwait->taskwait_sem);
+ }
+ }
+ }
+ if (taskgroup)
+ {
+ priority_queue_insert (PQ_TASKGROUP, &taskgroup->taskgroup_queue,
+ task, task->priority,
+ PRIORITY_INSERT_BEGIN,
+ /*adjust_parent_depends_on=*/false,
+ task->parent_depends_on);
+ if (taskgroup->in_taskgroup_wait)
+ {
+ /* One more task has had its dependencies met.
+ Inform any waiters. */
+ taskgroup->in_taskgroup_wait = false;
+ gomp_sem_post (&taskgroup->taskgroup_sem);
+ }
+ }
+ priority_queue_insert (PQ_TEAM, &team->task_queue,
+ task, task->priority,
+ PRIORITY_INSERT_END,
+ /*adjust_parent_depends_on=*/false,
+ task->parent_depends_on);
+ ++team->task_count;
+ ++team->task_queued_count;
+ ++ret;
+ }
+ free (child_task->dependers);
+ child_task->dependers = NULL;
+ if (ret > 1)
+ gomp_team_barrier_set_task_pending (&team->barrier);
+ return ret;
+}
+
+static inline size_t
+gomp_task_run_post_handle_depend (struct gomp_task *child_task,
+ struct gomp_team *team)
+{
+ if (child_task->depend_count == 0)
+ return 0;
+
+ /* If parent is gone already, the hash table is freed and nothing
+ will use the hash table anymore, no need to remove anything from it. */
+ if (child_task->parent != NULL)
+ gomp_task_run_post_handle_depend_hash (child_task);
+
+ if (child_task->dependers == NULL)
+ return 0;
+
+ return gomp_task_run_post_handle_dependers (child_task, team);
+}
+
+/* Remove CHILD_TASK from its parent. */
+
+static inline void
+gomp_task_run_post_remove_parent (struct gomp_task *child_task)
+{
+ struct gomp_task *parent = child_task->parent;
+ if (parent == NULL)
+ return;
+
+ /* If this was the last task the parent was depending on,
+ synchronize with gomp_task_maybe_wait_for_dependencies so it can
+ clean up and return. */
+ if (__builtin_expect (child_task->parent_depends_on, 0)
+ && --parent->taskwait->n_depend == 0
+ && parent->taskwait->in_depend_wait)
+ {
+ parent->taskwait->in_depend_wait = false;
+ gomp_sem_post (&parent->taskwait->taskwait_sem);
+ }
+
+ if (priority_queue_remove (PQ_CHILDREN, &parent->children_queue,
+ child_task, MEMMODEL_RELEASE)
+ && parent->taskwait && parent->taskwait->in_taskwait)
+ {
+ parent->taskwait->in_taskwait = false;
+ gomp_sem_post (&parent->taskwait->taskwait_sem);
+ }
+ child_task->pnode[PQ_CHILDREN].next = NULL;
+ child_task->pnode[PQ_CHILDREN].prev = NULL;
+}
+
+/* Remove CHILD_TASK from its taskgroup. */
+
+static inline void
+gomp_task_run_post_remove_taskgroup (struct gomp_task *child_task)
+{
+ struct gomp_taskgroup *taskgroup = child_task->taskgroup;
+ if (taskgroup == NULL)
+ return;
+ bool empty = priority_queue_remove (PQ_TASKGROUP,
+ &taskgroup->taskgroup_queue,
+ child_task, MEMMODEL_RELAXED);
+ child_task->pnode[PQ_TASKGROUP].next = NULL;
+ child_task->pnode[PQ_TASKGROUP].prev = NULL;
+ if (taskgroup->num_children > 1)
+ --taskgroup->num_children;
+ else
+ {
+ /* We access taskgroup->num_children in GOMP_taskgroup_end
+ outside of the task lock mutex region, so
+ need a release barrier here to ensure memory
+ written by child_task->fn above is flushed
+ before the NULL is written. */
+ __atomic_store_n (&taskgroup->num_children, 0, MEMMODEL_RELEASE);
+ }
+ if (empty && taskgroup->in_taskgroup_wait)
+ {
+ taskgroup->in_taskgroup_wait = false;
+ gomp_sem_post (&taskgroup->taskgroup_sem);
+ }
+}
+
void
gomp_barrier_handle_tasks (gomp_barrier_state_t state)
{
struct gomp_task *task = thr->task;
struct gomp_task *child_task = NULL;
struct gomp_task *to_free = NULL;
+ int do_wake = 0;
gomp_mutex_lock (&team->task_lock);
if (gomp_barrier_last_thread (state))
while (1)
{
- if (team->task_queue != NULL)
+ bool cancelled = false;
+ if (!priority_queue_empty_p (&team->task_queue, MEMMODEL_RELAXED))
{
- struct gomp_task *parent;
-
- child_task = team->task_queue;
- parent = child_task->parent;
- if (parent && parent->children == child_task)
- parent->children = child_task->next_child;
- child_task->prev_queue->next_queue = child_task->next_queue;
- child_task->next_queue->prev_queue = child_task->prev_queue;
- if (child_task->next_queue != child_task)
- team->task_queue = child_task->next_queue;
- else
- team->task_queue = NULL;
- child_task->kind = GOMP_TASK_TIED;
+ bool ignored;
+ child_task
+ = priority_queue_next_task (PQ_TEAM, &team->task_queue,
+ PQ_IGNORED, NULL,
+ &ignored);
+ cancelled = gomp_task_run_pre (child_task, child_task->parent,
+ team);
+ if (__builtin_expect (cancelled, 0))
+ {
+ if (to_free)
+ {
+ gomp_finish_task (to_free);
+ free (to_free);
+ to_free = NULL;
+ }
+ goto finish_cancelled;
+ }
team->task_running_count++;
- if (team->task_count == team->task_running_count)
- gomp_team_barrier_clear_task_pending (&team->barrier);
+ child_task->in_tied_task = true;
}
gomp_mutex_unlock (&team->task_lock);
+ if (do_wake)
+ {
+ gomp_team_barrier_wake (&team->barrier, do_wake);
+ do_wake = 0;
+ }
if (to_free)
{
gomp_finish_task (to_free);
if (child_task)
{
thr->task = child_task;
- child_task->fn (child_task->fn_data);
+ if (__builtin_expect (child_task->fn == NULL, 0))
+ {
+ if (gomp_target_task_fn (child_task->fn_data))
+ {
+ thr->task = task;
+ gomp_mutex_lock (&team->task_lock);
+ child_task->kind = GOMP_TASK_ASYNC_RUNNING;
+ team->task_running_count--;
+ struct gomp_target_task *ttask
+ = (struct gomp_target_task *) child_task->fn_data;
+ /* If GOMP_PLUGIN_target_task_completion has run already
+ in between gomp_target_task_fn and the mutex lock,
+ perform the requeuing here. */
+ if (ttask->state == GOMP_TARGET_TASK_FINISHED)
+ gomp_target_task_completion (team, child_task);
+ else
+ ttask->state = GOMP_TARGET_TASK_RUNNING;
+ child_task = NULL;
+ continue;
+ }
+ }
+ else
+ child_task->fn (child_task->fn_data);
thr->task = task;
}
else
gomp_mutex_lock (&team->task_lock);
if (child_task)
{
- struct gomp_task *parent = child_task->parent;
- if (parent)
- {
- child_task->prev_child->next_child = child_task->next_child;
- child_task->next_child->prev_child = child_task->prev_child;
- if (parent->children == child_task)
- {
- if (child_task->next_child != child_task)
- parent->children = child_task->next_child;
- else
- {
- parent->children = NULL;
- if (parent->in_taskwait)
- gomp_sem_post (&parent->taskwait_sem);
- }
- }
- }
- gomp_clear_parent (child_task->children);
+ finish_cancelled:;
+ size_t new_tasks
+ = gomp_task_run_post_handle_depend (child_task, team);
+ gomp_task_run_post_remove_parent (child_task);
+ gomp_clear_parent (&child_task->children_queue);
+ gomp_task_run_post_remove_taskgroup (child_task);
to_free = child_task;
child_task = NULL;
- team->task_running_count--;
+ if (!cancelled)
+ team->task_running_count--;
+ if (new_tasks > 1)
+ {
+ do_wake = team->nthreads - team->task_running_count;
+ if (do_wake > new_tasks)
+ do_wake = new_tasks;
+ }
if (--team->task_count == 0
&& gomp_team_barrier_waiting_for_tasks (&team->barrier))
{
gomp_team_barrier_done (&team->barrier, state);
gomp_mutex_unlock (&team->task_lock);
gomp_team_barrier_wake (&team->barrier, 0);
+ gomp_mutex_lock (&team->task_lock);
}
}
}
}
-/* Called when encountering a taskwait directive. */
+/* Called when encountering a taskwait directive.
+
+ Wait for all children of the current task. */
void
GOMP_taskwait (void)
struct gomp_task *task = thr->task;
struct gomp_task *child_task = NULL;
struct gomp_task *to_free = NULL;
+ struct gomp_taskwait taskwait;
+ int do_wake = 0;
- if (task == NULL || task->children == NULL)
+ /* The acquire barrier on load of task->children here synchronizes
+ with the write of a NULL in gomp_task_run_post_remove_parent. It is
+ not necessary that we synchronize with other non-NULL writes at
+ this point, but we must ensure that all writes to memory by a
+ child thread task work function are seen before we exit from
+ GOMP_taskwait. */
+ if (task == NULL
+ || priority_queue_empty_p (&task->children_queue, MEMMODEL_ACQUIRE))
return;
+
+ memset (&taskwait, 0, sizeof (taskwait));
+ bool child_q = false;
gomp_mutex_lock (&team->task_lock);
while (1)
{
- if (task->children == NULL)
+ bool cancelled = false;
+ if (priority_queue_empty_p (&task->children_queue, MEMMODEL_RELAXED))
{
+ bool destroy_taskwait = task->taskwait != NULL;
+ task->taskwait = NULL;
gomp_mutex_unlock (&team->task_lock);
if (to_free)
{
gomp_finish_task (to_free);
free (to_free);
}
+ if (destroy_taskwait)
+ gomp_sem_destroy (&taskwait.taskwait_sem);
return;
}
- if (task->children->kind == GOMP_TASK_WAITING)
+ struct gomp_task *next_task
+ = priority_queue_next_task (PQ_CHILDREN, &task->children_queue,
+ PQ_TEAM, &team->task_queue, &child_q);
+ if (next_task->kind == GOMP_TASK_WAITING)
{
- child_task = task->children;
- task->children = child_task->next_child;
- child_task->prev_queue->next_queue = child_task->next_queue;
- child_task->next_queue->prev_queue = child_task->prev_queue;
- if (team->task_queue == child_task)
+ child_task = next_task;
+ cancelled
+ = gomp_task_run_pre (child_task, task, team);
+ if (__builtin_expect (cancelled, 0))
{
- if (child_task->next_queue != child_task)
- team->task_queue = child_task->next_queue;
- else
- team->task_queue = NULL;
+ if (to_free)
+ {
+ gomp_finish_task (to_free);
+ free (to_free);
+ to_free = NULL;
+ }
+ goto finish_cancelled;
}
- child_task->kind = GOMP_TASK_TIED;
- team->task_running_count++;
- if (team->task_count == team->task_running_count)
- gomp_team_barrier_clear_task_pending (&team->barrier);
}
else
- /* All tasks we are waiting for are already running
- in other threads. Wait for them. */
- task->in_taskwait = true;
+ {
+ /* All tasks we are waiting for are either running in other
+ threads, or they are tasks that have not had their
+ dependencies met (so they're not even in the queue). Wait
+ for them. */
+ if (task->taskwait == NULL)
+ {
+ taskwait.in_depend_wait = false;
+ gomp_sem_init (&taskwait.taskwait_sem, 0);
+ task->taskwait = &taskwait;
+ }
+ taskwait.in_taskwait = true;
+ }
gomp_mutex_unlock (&team->task_lock);
+ if (do_wake)
+ {
+ gomp_team_barrier_wake (&team->barrier, do_wake);
+ do_wake = 0;
+ }
if (to_free)
{
gomp_finish_task (to_free);
if (child_task)
{
thr->task = child_task;
- child_task->fn (child_task->fn_data);
+ if (__builtin_expect (child_task->fn == NULL, 0))
+ {
+ if (gomp_target_task_fn (child_task->fn_data))
+ {
+ thr->task = task;
+ gomp_mutex_lock (&team->task_lock);
+ child_task->kind = GOMP_TASK_ASYNC_RUNNING;
+ struct gomp_target_task *ttask
+ = (struct gomp_target_task *) child_task->fn_data;
+ /* If GOMP_PLUGIN_target_task_completion has run already
+ in between gomp_target_task_fn and the mutex lock,
+ perform the requeuing here. */
+ if (ttask->state == GOMP_TARGET_TASK_FINISHED)
+ gomp_target_task_completion (team, child_task);
+ else
+ ttask->state = GOMP_TARGET_TASK_RUNNING;
+ child_task = NULL;
+ continue;
+ }
+ }
+ else
+ child_task->fn (child_task->fn_data);
thr->task = task;
}
else
+ gomp_sem_wait (&taskwait.taskwait_sem);
+ gomp_mutex_lock (&team->task_lock);
+ if (child_task)
+ {
+ finish_cancelled:;
+ size_t new_tasks
+ = gomp_task_run_post_handle_depend (child_task, team);
+
+ if (child_q)
+ {
+ priority_queue_remove (PQ_CHILDREN, &task->children_queue,
+ child_task, MEMMODEL_RELAXED);
+ child_task->pnode[PQ_CHILDREN].next = NULL;
+ child_task->pnode[PQ_CHILDREN].prev = NULL;
+ }
+
+ gomp_clear_parent (&child_task->children_queue);
+
+ gomp_task_run_post_remove_taskgroup (child_task);
+
+ to_free = child_task;
+ child_task = NULL;
+ team->task_count--;
+ if (new_tasks > 1)
+ {
+ do_wake = team->nthreads - team->task_running_count
+ - !task->in_tied_task;
+ if (do_wake > new_tasks)
+ do_wake = new_tasks;
+ }
+ }
+ }
+}
+
+/* An undeferred task is about to run. Wait for all tasks that this
+ undeferred task depends on.
+
+ This is done by first putting all known ready dependencies
+ (dependencies that have their own dependencies met) at the top of
+ the scheduling queues. Then we iterate through these imminently
+ ready tasks (and possibly other high priority tasks), and run them.
+ If we run out of ready dependencies to execute, we either wait for
+ the reamining dependencies to finish, or wait for them to get
+ scheduled so we can run them.
+
+ DEPEND is as in GOMP_task. */
+
+void
+gomp_task_maybe_wait_for_dependencies (void **depend)
+{
+ struct gomp_thread *thr = gomp_thread ();
+ struct gomp_task *task = thr->task;
+ struct gomp_team *team = thr->ts.team;
+ struct gomp_task_depend_entry elem, *ent = NULL;
+ struct gomp_taskwait taskwait;
+ size_t ndepend = (uintptr_t) depend[0];
+ size_t nout = (uintptr_t) depend[1];
+ size_t i;
+ size_t num_awaited = 0;
+ struct gomp_task *child_task = NULL;
+ struct gomp_task *to_free = NULL;
+ int do_wake = 0;
+
+ gomp_mutex_lock (&team->task_lock);
+ for (i = 0; i < ndepend; i++)
+ {
+ elem.addr = depend[i + 2];
+ ent = htab_find (task->depend_hash, &elem);
+ for (; ent; ent = ent->next)
+ if (i >= nout && ent->is_in)
+ continue;
+ else
+ {
+ struct gomp_task *tsk = ent->task;
+ if (!tsk->parent_depends_on)
+ {
+ tsk->parent_depends_on = true;
+ ++num_awaited;
+ /* If depenency TSK itself has no dependencies and is
+ ready to run, move it up front so that we run it as
+ soon as possible. */
+ if (tsk->num_dependees == 0 && tsk->kind == GOMP_TASK_WAITING)
+ priority_queue_upgrade_task (tsk, task);
+ }
+ }
+ }
+ if (num_awaited == 0)
+ {
+ gomp_mutex_unlock (&team->task_lock);
+ return;
+ }
+
+ memset (&taskwait, 0, sizeof (taskwait));
+ taskwait.n_depend = num_awaited;
+ gomp_sem_init (&taskwait.taskwait_sem, 0);
+ task->taskwait = &taskwait;
+
+ while (1)
+ {
+ bool cancelled = false;
+ if (taskwait.n_depend == 0)
{
- gomp_sem_wait (&task->taskwait_sem);
- task->in_taskwait = false;
+ task->taskwait = NULL;
+ gomp_mutex_unlock (&team->task_lock);
+ if (to_free)
+ {
+ gomp_finish_task (to_free);
+ free (to_free);
+ }
+ gomp_sem_destroy (&taskwait.taskwait_sem);
return;
}
- gomp_mutex_lock (&team->task_lock);
+
+ /* Theoretically when we have multiple priorities, we should
+ chose between the highest priority item in
+ task->children_queue and team->task_queue here, so we should
+ use priority_queue_next_task(). However, since we are
+ running an undeferred task, perhaps that makes all tasks it
+ depends on undeferred, thus a priority of INF? This would
+ make it unnecessary to take anything into account here,
+ but the dependencies.
+
+ On the other hand, if we want to use priority_queue_next_task(),
+ care should be taken to only use priority_queue_remove()
+ below if the task was actually removed from the children
+ queue. */
+ bool ignored;
+ struct gomp_task *next_task
+ = priority_queue_next_task (PQ_CHILDREN, &task->children_queue,
+ PQ_IGNORED, NULL, &ignored);
+
+ if (next_task->kind == GOMP_TASK_WAITING)
+ {
+ child_task = next_task;
+ cancelled
+ = gomp_task_run_pre (child_task, task, team);
+ if (__builtin_expect (cancelled, 0))
+ {
+ if (to_free)
+ {
+ gomp_finish_task (to_free);
+ free (to_free);
+ to_free = NULL;
+ }
+ goto finish_cancelled;
+ }
+ }
+ else
+ /* All tasks we are waiting for are either running in other
+ threads, or they are tasks that have not had their
+ dependencies met (so they're not even in the queue). Wait
+ for them. */
+ taskwait.in_depend_wait = true;
+ gomp_mutex_unlock (&team->task_lock);
+ if (do_wake)
+ {
+ gomp_team_barrier_wake (&team->barrier, do_wake);
+ do_wake = 0;
+ }
+ if (to_free)
+ {
+ gomp_finish_task (to_free);
+ free (to_free);
+ to_free = NULL;
+ }
if (child_task)
{
- child_task->prev_child->next_child = child_task->next_child;
- child_task->next_child->prev_child = child_task->prev_child;
- if (task->children == child_task)
+ thr->task = child_task;
+ if (__builtin_expect (child_task->fn == NULL, 0))
{
- if (child_task->next_child != child_task)
- task->children = child_task->next_child;
- else
- task->children = NULL;
+ if (gomp_target_task_fn (child_task->fn_data))
+ {
+ thr->task = task;
+ gomp_mutex_lock (&team->task_lock);
+ child_task->kind = GOMP_TASK_ASYNC_RUNNING;
+ struct gomp_target_task *ttask
+ = (struct gomp_target_task *) child_task->fn_data;
+ /* If GOMP_PLUGIN_target_task_completion has run already
+ in between gomp_target_task_fn and the mutex lock,
+ perform the requeuing here. */
+ if (ttask->state == GOMP_TARGET_TASK_FINISHED)
+ gomp_target_task_completion (team, child_task);
+ else
+ ttask->state = GOMP_TARGET_TASK_RUNNING;
+ child_task = NULL;
+ continue;
+ }
}
- gomp_clear_parent (child_task->children);
+ else
+ child_task->fn (child_task->fn_data);
+ thr->task = task;
+ }
+ else
+ gomp_sem_wait (&taskwait.taskwait_sem);
+ gomp_mutex_lock (&team->task_lock);
+ if (child_task)
+ {
+ finish_cancelled:;
+ size_t new_tasks
+ = gomp_task_run_post_handle_depend (child_task, team);
+ if (child_task->parent_depends_on)
+ --taskwait.n_depend;
+
+ priority_queue_remove (PQ_CHILDREN, &task->children_queue,
+ child_task, MEMMODEL_RELAXED);
+ child_task->pnode[PQ_CHILDREN].next = NULL;
+ child_task->pnode[PQ_CHILDREN].prev = NULL;
+
+ gomp_clear_parent (&child_task->children_queue);
+ gomp_task_run_post_remove_taskgroup (child_task);
to_free = child_task;
child_task = NULL;
team->task_count--;
- team->task_running_count--;
+ if (new_tasks > 1)
+ {
+ do_wake = team->nthreads - team->task_running_count
+ - !task->in_tied_task;
+ if (do_wake > new_tasks)
+ do_wake = new_tasks;
+ }
}
}
}
/* Nothing at the moment. */
}
+void
+GOMP_taskgroup_start (void)
+{
+ struct gomp_thread *thr = gomp_thread ();
+ struct gomp_team *team = thr->ts.team;
+ struct gomp_task *task = thr->task;
+ struct gomp_taskgroup *taskgroup;
+
+ /* If team is NULL, all tasks are executed as
+ GOMP_TASK_UNDEFERRED tasks and thus all children tasks of
+ taskgroup and their descendant tasks will be finished
+ by the time GOMP_taskgroup_end is called. */
+ if (team == NULL)
+ return;
+ taskgroup = gomp_malloc (sizeof (struct gomp_taskgroup));
+ taskgroup->prev = task->taskgroup;
+ priority_queue_init (&taskgroup->taskgroup_queue);
+ taskgroup->in_taskgroup_wait = false;
+ taskgroup->cancelled = false;
+ taskgroup->num_children = 0;
+ gomp_sem_init (&taskgroup->taskgroup_sem, 0);
+ task->taskgroup = taskgroup;
+}
+
+void
+GOMP_taskgroup_end (void)
+{
+ struct gomp_thread *thr = gomp_thread ();
+ struct gomp_team *team = thr->ts.team;
+ struct gomp_task *task = thr->task;
+ struct gomp_taskgroup *taskgroup;
+ struct gomp_task *child_task = NULL;
+ struct gomp_task *to_free = NULL;
+ int do_wake = 0;
+
+ if (team == NULL)
+ return;
+ taskgroup = task->taskgroup;
+ if (__builtin_expect (taskgroup == NULL, 0)
+ && thr->ts.level == 0)
+ {
+ /* This can happen if GOMP_taskgroup_start is called when
+ thr->ts.team == NULL, but inside of the taskgroup there
+ is #pragma omp target nowait that creates an implicit
+ team with a single thread. In this case, we want to wait
+ for all outstanding tasks in this team. */
+ gomp_team_barrier_wait (&team->barrier);
+ return;
+ }
+
+ /* The acquire barrier on load of taskgroup->num_children here
+ synchronizes with the write of 0 in gomp_task_run_post_remove_taskgroup.
+ It is not necessary that we synchronize with other non-0 writes at
+ this point, but we must ensure that all writes to memory by a
+ child thread task work function are seen before we exit from
+ GOMP_taskgroup_end. */
+ if (__atomic_load_n (&taskgroup->num_children, MEMMODEL_ACQUIRE) == 0)
+ goto finish;
+
+ bool unused;
+ gomp_mutex_lock (&team->task_lock);
+ while (1)
+ {
+ bool cancelled = false;
+ if (priority_queue_empty_p (&taskgroup->taskgroup_queue,
+ MEMMODEL_RELAXED))
+ {
+ if (taskgroup->num_children)
+ {
+ if (priority_queue_empty_p (&task->children_queue,
+ MEMMODEL_RELAXED))
+ goto do_wait;
+ child_task
+ = priority_queue_next_task (PQ_CHILDREN, &task->children_queue,
+ PQ_TEAM, &team->task_queue,
+ &unused);
+ }
+ else
+ {
+ gomp_mutex_unlock (&team->task_lock);
+ if (to_free)
+ {
+ gomp_finish_task (to_free);
+ free (to_free);
+ }
+ goto finish;
+ }
+ }
+ else
+ child_task
+ = priority_queue_next_task (PQ_TASKGROUP, &taskgroup->taskgroup_queue,
+ PQ_TEAM, &team->task_queue, &unused);
+ if (child_task->kind == GOMP_TASK_WAITING)
+ {
+ cancelled
+ = gomp_task_run_pre (child_task, child_task->parent, team);
+ if (__builtin_expect (cancelled, 0))
+ {
+ if (to_free)
+ {
+ gomp_finish_task (to_free);
+ free (to_free);
+ to_free = NULL;
+ }
+ goto finish_cancelled;
+ }
+ }
+ else
+ {
+ child_task = NULL;
+ do_wait:
+ /* All tasks we are waiting for are either running in other
+ threads, or they are tasks that have not had their
+ dependencies met (so they're not even in the queue). Wait
+ for them. */
+ taskgroup->in_taskgroup_wait = true;
+ }
+ gomp_mutex_unlock (&team->task_lock);
+ if (do_wake)
+ {
+ gomp_team_barrier_wake (&team->barrier, do_wake);
+ do_wake = 0;
+ }
+ if (to_free)
+ {
+ gomp_finish_task (to_free);
+ free (to_free);
+ to_free = NULL;
+ }
+ if (child_task)
+ {
+ thr->task = child_task;
+ if (__builtin_expect (child_task->fn == NULL, 0))
+ {
+ if (gomp_target_task_fn (child_task->fn_data))
+ {
+ thr->task = task;
+ gomp_mutex_lock (&team->task_lock);
+ child_task->kind = GOMP_TASK_ASYNC_RUNNING;
+ struct gomp_target_task *ttask
+ = (struct gomp_target_task *) child_task->fn_data;
+ /* If GOMP_PLUGIN_target_task_completion has run already
+ in between gomp_target_task_fn and the mutex lock,
+ perform the requeuing here. */
+ if (ttask->state == GOMP_TARGET_TASK_FINISHED)
+ gomp_target_task_completion (team, child_task);
+ else
+ ttask->state = GOMP_TARGET_TASK_RUNNING;
+ child_task = NULL;
+ continue;
+ }
+ }
+ else
+ child_task->fn (child_task->fn_data);
+ thr->task = task;
+ }
+ else
+ gomp_sem_wait (&taskgroup->taskgroup_sem);
+ gomp_mutex_lock (&team->task_lock);
+ if (child_task)
+ {
+ finish_cancelled:;
+ size_t new_tasks
+ = gomp_task_run_post_handle_depend (child_task, team);
+ gomp_task_run_post_remove_parent (child_task);
+ gomp_clear_parent (&child_task->children_queue);
+ gomp_task_run_post_remove_taskgroup (child_task);
+ to_free = child_task;
+ child_task = NULL;
+ team->task_count--;
+ if (new_tasks > 1)
+ {
+ do_wake = team->nthreads - team->task_running_count
+ - !task->in_tied_task;
+ if (do_wake > new_tasks)
+ do_wake = new_tasks;
+ }
+ }
+ }
+
+ finish:
+ task->taskgroup = taskgroup->prev;
+ gomp_sem_destroy (&taskgroup->taskgroup_sem);
+ free (taskgroup);
+}
+
int
omp_in_final (void)
{