MINOR: tasks: do not maintain the rqueue_size counter anymore

This one is exclusively used as a boolean nowadays and is non-zero only
when the thread-local run queue is not empty. Better check the root tree's
pointer and avoid updating this counter all the time.
This commit is contained in:
Willy Tarreau 2021-02-24 16:13:03 +01:00
parent 9c7b8085f4
commit 2c41d77ebc
3 changed files with 5 additions and 12 deletions

View File

@ -78,10 +78,9 @@ struct task_per_thread {
struct list tasklets[TL_CLASSES]; /* tasklets (and/or tasks) to run, by class */
unsigned int rqueue_ticks; /* Insertion counter for the run queue */
int task_list_size; /* Number of tasks among the tasklets */
int rqueue_size; /* Number of elements in the per-thread run queue */
int current_queue; /* points to current tasklet list being run, -1 if none */
struct task *current; /* current task (not tasklet) */
unsigned int rq_total; /* total size of the run queue, prio_tree + tasklets */
struct task *current; /* current task (not tasklet) */
uint8_t tl_class_mask; /* bit mask of non-empty tasklets classes */
__attribute__((aligned(64))) char end[0];
};

View File

@ -179,7 +179,7 @@ static inline int task_in_wq(struct task *t)
static inline int thread_has_tasks(void)
{
return (!!(global_tasks_mask & tid_bit) |
(sched->rqueue_size > 0) |
!eb_is_empty(&sched->rqueue) |
!!sched->tl_class_mask |
!MT_LIST_ISEMPTY(&sched->shared_tasklet_list));
}
@ -325,7 +325,6 @@ static inline struct task *__task_unlink_rq(struct task *t)
else
#endif
{
sched->rqueue_size--;
_HA_ATOMIC_SUB(&sched->rq_total, 1);
}
eb32sc_delete(&t->rq);

View File

@ -150,13 +150,8 @@ void __task_wakeup(struct task *t, struct eb_root *root)
if (root == &rqueue) {
_HA_ATOMIC_OR(&t->state, TASK_GLOBAL);
HA_SPIN_UNLOCK(TASK_RQ_LOCK, &rq_lock);
} else
#endif
{
int nb = ((void *)root - (void *)&task_per_thread[0].rqueue) / sizeof(task_per_thread[0]);
task_per_thread[nb].rqueue_size++;
}
#ifdef USE_THREAD
/* If all threads that are supposed to handle this task are sleeping,
* wake one.
*/
@ -428,7 +423,7 @@ unsigned int run_tasks_from_lists(unsigned int budgets[])
if (unlikely(queue > TL_NORMAL &&
budget_mask & (1 << TL_NORMAL) &&
((sched->rqueue_size > 0) ||
(!eb_is_empty(&sched->rqueue) ||
(global_tasks_mask & tid_bit)))) {
/* a task was woken up by a bulk tasklet or another thread */
break;
@ -609,7 +604,7 @@ void process_runnable_tasks()
/* normal tasklets list gets a default weight of ~37% */
if ((tt->tl_class_mask & (1 << TL_NORMAL)) ||
(sched->rqueue_size > 0) || (global_tasks_mask & tid_bit))
!eb_is_empty(&sched->rqueue) || (global_tasks_mask & tid_bit))
max[TL_NORMAL] = default_weights[TL_NORMAL];
/* bulk tasklets list gets a default weight of ~13% */