On 08/27/2015 07:14 AM, Jakub Jelinek wrote:
On Thu, Aug 27, 2015 at 07:01:48AM -0700, Aldy Hernandez wrote:
commit 45fdbc84123fefde6bf99aaf87099317aaa38f24
Author: Aldy Hernandez <al...@redhat.com>
Date: Wed Aug 26 07:28:39 2015 -0700
* libgomp.h (enum gomp_task_kind): Comment fields.
(struct gomp_task): Comment some fields.
* task.c (GOMP_task): Add comments.
(gomp_task_run_pre): Same.
diff --git a/libgomp/libgomp.h b/libgomp/libgomp.h
index 3d705ef..34f064c 100644
--- a/libgomp/libgomp.h
+++ b/libgomp/libgomp.h
@@ -263,9 +263,13 @@ extern char *goacc_device_type;
enum gomp_task_kind
{
+ /* Thread not directly created by user. For instance, when creating
+ a team of threads or an ICV. */
That is misleading, especially with the (possibly) upcoming thread task.
"implicit task" is an OpenMP tasking term:
Ah, fixed.
"A task generated by an implicit parallel region or generated when a parallel
construct is encountered during execution."
but there is really no reason to explain what it is, so you should just say
in the comment
/* Implicit task. */
GOMP_TASK_IMPLICIT,
GOMP_TASK_IFFALSE,
This is for if (0) tasks. The right OpenMP tasking term is "undeferred
task", perhaps we should just replace GOMP_TASK_IFFALSE with
GOMP_TASK_UNDEFERRED everywhere.
Done.
+ /* Task created by GOMP_task and waiting to be run. */
GOMP_TASK_WAITING,
+ /* Task currently scheduled and about to execute. */
Well, not just about to execute, that kind is used even for the task that is
already executing.
Fixed.
Otherwise LGTM.
Committed.
commit 862e81ee2d71f33eb09041061d3b1db1671495f8
Author: Aldy Hernandez <al...@redhat.com>
Date: Wed Aug 26 07:28:39 2015 -0700
* libgomp.h (enum gomp_task_kind): Comment fields.
(struct gomp_task): Comment some fields.
* task.c (GOMP_task): Add comments.
Rename GOMP_TASK_IFFALSE to GOMP_TASK_UNDEFERRED.
(gomp_task_run_pre): Add comments.
(GOMP_taskgroup_start): Rename GOMP_TASK_IFFALSE to
GOMP_TASK_UNDEFERRED.
* taskloop.c (GOMP_taskloop): Same.
diff --git a/libgomp/libgomp.h b/libgomp/libgomp.h
index 3d705ef..f855813 100644
--- a/libgomp/libgomp.h
+++ b/libgomp/libgomp.h
@@ -263,9 +263,13 @@ extern char *goacc_device_type;
enum gomp_task_kind
{
+ /* Implicit task. */
GOMP_TASK_IMPLICIT,
- GOMP_TASK_IFFALSE,
+ /* Undeferred task. */
+ GOMP_TASK_UNDEFERRED,
+ /* Task created by GOMP_task and waiting to be run. */
GOMP_TASK_WAITING,
+ /* Task currently executing or scheduled and about to execute. */
GOMP_TASK_TIED
};
@@ -313,8 +317,11 @@ struct gomp_task
struct gomp_task *prev_child;
struct gomp_task *next_queue;
struct gomp_task *prev_queue;
+ /* Next task in the current taskgroup. */
struct gomp_task *next_taskgroup;
+ /* Previous task in the current taskgroup. */
struct gomp_task *prev_taskgroup;
+ /* Taskgroup this task belongs in. */
struct gomp_taskgroup *taskgroup;
struct gomp_dependers_vec *dependers;
struct htab *depend_hash;
diff --git a/libgomp/task.c b/libgomp/task.c
index 009a9f8..aa7ae4d 100644
--- a/libgomp/task.c
+++ b/libgomp/task.c
@@ -165,7 +165,7 @@ GOMP_task (void (*fn) (void *), void *data, void (*cpyfn)
(void *, void *),
gomp_task_maybe_wait_for_dependencies (depend);
gomp_init_task (&task, thr->task, gomp_icv (false));
- task.kind = GOMP_TASK_IFFALSE;
+ task.kind = GOMP_TASK_UNDEFERRED;
task.final_task = (thr->task && thr->task->final_task)
|| (flags & GOMP_TASK_FLAG_FINAL);
if (thr->task)
@@ -218,7 +218,7 @@ GOMP_task (void (*fn) (void *), void *data, void (*cpyfn)
(void *, void *),
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->kind = GOMP_TASK_UNDEFERRED;
task->in_tied_task = parent->in_tied_task;
task->taskgroup = taskgroup;
thr->task = task;
@@ -388,6 +388,7 @@ GOMP_task (void (*fn) (void *), void *data, void (*cpyfn)
(void *, void *),
parent->children = task;
if (taskgroup)
{
+ /* If applicable, place task into its taskgroup. */
if (taskgroup->children)
{
task->next_taskgroup = taskgroup->children;
@@ -451,7 +452,14 @@ gomp_task_run_pre (struct gomp_task *child_task, struct
gomp_task *parent,
{
if (parent)
{
- /* Remove child_task from parent. */
+ /* Adjust children such that it will point to a next child,
+ while the current one is scheduled to be executed. This way,
+ GOMP_taskwait (and others) can schedule a next task while
+ waiting.
+
+ Do not remove it entirely from the circular list, as it is
+ still a child, though not one we should consider first (say
+ by GOMP_taskwait). */
if (parent->children == child_task)
parent->children = child_task->next_child;
@@ -465,10 +473,14 @@ gomp_task_run_pre (struct gomp_task *child_task, struct
gomp_task *parent,
parent->taskwait->last_parent_depends_on = NULL;
}
}
- /* Remove child_task from taskgroup. */
+
+ /* Adjust taskgroup to point to the next taskgroup. See note above
+ regarding adjustment of children as to why the child_task is not
+ removed entirely from the circular list. */
if (taskgroup && taskgroup->children == child_task)
taskgroup->children = child_task->next_taskgroup;
+ /* Remove child_task from the task_queue. */
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)
@@ -479,6 +491,7 @@ gomp_task_run_pre (struct gomp_task *child_task, struct
gomp_task *parent,
team->task_queue = 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)
@@ -1137,7 +1150,7 @@ GOMP_taskgroup_start (void)
struct gomp_taskgroup *taskgroup;
/* If team is NULL, all tasks are executed as
- GOMP_TASK_IFFALSE tasks and thus all children tasks of
+ 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)
diff --git a/libgomp/taskloop.c b/libgomp/taskloop.c
index 1a2b85d..f57a5a1 100644
--- a/libgomp/taskloop.c
+++ b/libgomp/taskloop.c
@@ -175,7 +175,7 @@ GOMP_taskloop (void (*fn) (void *), void *data, void
(*cpyfn) (void *, void *),
for (i = 0; i < num_tasks; i++)
{
gomp_init_task (&task[i], parent, gomp_icv (false));
- task[i].kind = GOMP_TASK_IFFALSE;
+ task[i].kind = GOMP_TASK_UNDEFERRED;
task[i].final_task = (thr->task && thr->task->final_task)
|| (flags & GOMP_TASK_FLAG_FINAL);
if (thr->task)
@@ -213,7 +213,7 @@ GOMP_taskloop (void (*fn) (void *), void *data, void
(*cpyfn) (void *, void *),
struct gomp_task task;
gomp_init_task (&task, thr->task, gomp_icv (false));
- task.kind = GOMP_TASK_IFFALSE;
+ task.kind = GOMP_TASK_UNDEFERRED;
task.final_task = (thr->task && thr->task->final_task)
|| (flags & GOMP_TASK_FLAG_FINAL);
if (thr->task)
@@ -254,7 +254,7 @@ GOMP_taskloop (void (*fn) (void *), void *data, void
(*cpyfn) (void *, void *),
arg = (char *) (((uintptr_t) (task + 1) + arg_align - 1)
& ~(uintptr_t) (arg_align - 1));
gomp_init_task (task, parent, gomp_icv (false));
- task->kind = GOMP_TASK_IFFALSE;
+ task->kind = GOMP_TASK_UNDEFERRED;
task->in_tied_task = parent->in_tied_task;
task->taskgroup = taskgroup;
thr->task = task;
