diff options
Diffstat (limited to 'kernel/padata.c')
-rw-r--r-- | kernel/padata.c | 88 |
1 files changed, 34 insertions, 54 deletions
diff --git a/kernel/padata.c b/kernel/padata.c index 6939111b3cbe..e82f066d63ac 100644 --- a/kernel/padata.c +++ b/kernel/padata.c @@ -66,15 +66,11 @@ static int padata_cpu_hash(struct parallel_data *pd) static void padata_parallel_worker(struct work_struct *parallel_work) { struct padata_parallel_queue *pqueue; - struct parallel_data *pd; - struct padata_instance *pinst; LIST_HEAD(local_list); local_bh_disable(); pqueue = container_of(parallel_work, struct padata_parallel_queue, work); - pd = pqueue->pd; - pinst = pd->pinst; spin_lock(&pqueue->parallel.lock); list_replace_init(&pqueue->parallel.list, &local_list); @@ -137,6 +133,7 @@ int padata_do_parallel(struct padata_instance *pinst, padata->cb_cpu = cb_cpu; target_cpu = padata_cpu_hash(pd); + padata->cpu = target_cpu; queue = per_cpu_ptr(pd->pqueue, target_cpu); spin_lock(&queue->parallel.lock); @@ -160,8 +157,6 @@ EXPORT_SYMBOL(padata_do_parallel); * A pointer to the control struct of the next object that needs * serialization, if present in one of the percpu reorder queues. * - * NULL, if all percpu reorder queues are empty. - * * -EINPROGRESS, if the next object that needs serialization will * be parallel processed by another cpu and is not yet present in * the cpu's reorder queue. @@ -171,25 +166,12 @@ EXPORT_SYMBOL(padata_do_parallel); */ static struct padata_priv *padata_get_next(struct parallel_data *pd) { - int cpu, num_cpus; - unsigned int next_nr, next_index; struct padata_parallel_queue *next_queue; struct padata_priv *padata; struct padata_list *reorder; + int cpu = pd->cpu; - num_cpus = cpumask_weight(pd->cpumask.pcpu); - - /* - * Calculate the percpu reorder queue and the sequence - * number of the next object. - */ - next_nr = pd->processed; - next_index = next_nr % num_cpus; - cpu = padata_index_to_cpu(pd, next_index); next_queue = per_cpu_ptr(pd->pqueue, cpu); - - padata = NULL; - reorder = &next_queue->reorder; spin_lock(&reorder->lock); @@ -200,7 +182,8 @@ static struct padata_priv *padata_get_next(struct parallel_data *pd) list_del_init(&padata->list); atomic_dec(&pd->reorder_objects); - pd->processed++; + pd->cpu = cpumask_next_wrap(cpu, pd->cpumask.pcpu, -1, + false); spin_unlock(&reorder->lock); goto out; @@ -223,6 +206,7 @@ static void padata_reorder(struct parallel_data *pd) struct padata_priv *padata; struct padata_serial_queue *squeue; struct padata_instance *pinst = pd->pinst; + struct padata_parallel_queue *next_queue; /* * We need to ensure that only one cpu can work on dequeueing of @@ -241,12 +225,11 @@ static void padata_reorder(struct parallel_data *pd) padata = padata_get_next(pd); /* - * All reorder queues are empty, or the next object that needs - * serialization is parallel processed by another cpu and is - * still on it's way to the cpu's reorder queue, nothing to - * do for now. + * If the next object that needs serialization is parallel + * processed by another cpu and is still on it's way to the + * cpu's reorder queue, nothing to do for now. */ - if (!padata || PTR_ERR(padata) == -EINPROGRESS) + if (PTR_ERR(padata) == -EINPROGRESS) break; /* @@ -255,7 +238,6 @@ static void padata_reorder(struct parallel_data *pd) * so exit immediately. */ if (PTR_ERR(padata) == -ENODATA) { - del_timer(&pd->timer); spin_unlock_bh(&pd->lock); return; } @@ -274,28 +256,27 @@ static void padata_reorder(struct parallel_data *pd) /* * The next object that needs serialization might have arrived to - * the reorder queues in the meantime, we will be called again - * from the timer function if no one else cares for it. + * the reorder queues in the meantime. * - * Ensure reorder_objects is read after pd->lock is dropped so we see - * an increment from another task in padata_do_serial. Pairs with + * Ensure reorder queue is read after pd->lock is dropped so we see + * new objects from another task in padata_do_serial. Pairs with * smp_mb__after_atomic in padata_do_serial. */ smp_mb(); - if (atomic_read(&pd->reorder_objects) - && !(pinst->flags & PADATA_RESET)) - mod_timer(&pd->timer, jiffies + HZ); - else - del_timer(&pd->timer); - return; + next_queue = per_cpu_ptr(pd->pqueue, pd->cpu); + if (!list_empty(&next_queue->reorder.list)) + queue_work(pinst->wq, &pd->reorder_work); } -static void padata_reorder_timer(unsigned long arg) +static void invoke_padata_reorder(struct work_struct *work) { - struct parallel_data *pd = (struct parallel_data *)arg; + struct parallel_data *pd; + local_bh_disable(); + pd = container_of(work, struct parallel_data, reorder_work); padata_reorder(pd); + local_bh_enable(); } static void padata_serial_worker(struct work_struct *serial_work) @@ -342,29 +323,22 @@ static void padata_serial_worker(struct work_struct *serial_work) */ void padata_do_serial(struct padata_priv *padata) { - int cpu; - struct padata_parallel_queue *pqueue; - struct parallel_data *pd; - - pd = padata->pd; - - cpu = get_cpu(); - pqueue = per_cpu_ptr(pd->pqueue, cpu); + struct parallel_data *pd = padata->pd; + struct padata_parallel_queue *pqueue = per_cpu_ptr(pd->pqueue, + padata->cpu); spin_lock(&pqueue->reorder.lock); - atomic_inc(&pd->reorder_objects); list_add_tail(&padata->list, &pqueue->reorder.list); + atomic_inc(&pd->reorder_objects); spin_unlock(&pqueue->reorder.lock); /* - * Ensure the atomic_inc of reorder_objects above is ordered correctly + * Ensure the addition to the reorder list is ordered correctly * with the trylock of pd->lock in padata_reorder. Pairs with smp_mb * in padata_reorder. */ smp_mb__after_atomic(); - put_cpu(); - padata_reorder(pd); } EXPORT_SYMBOL(padata_do_serial); @@ -413,9 +387,14 @@ static void padata_init_pqueues(struct parallel_data *pd) struct padata_parallel_queue *pqueue; cpu_index = 0; - for_each_cpu(cpu, pd->cpumask.pcpu) { + for_each_possible_cpu(cpu) { pqueue = per_cpu_ptr(pd->pqueue, cpu); - pqueue->pd = pd; + + if (!cpumask_test_cpu(cpu, pd->cpumask.pcpu)) { + pqueue->cpu_index = -1; + continue; + } + pqueue->cpu_index = cpu_index; cpu_index++; @@ -449,12 +428,13 @@ static struct parallel_data *padata_alloc_pd(struct padata_instance *pinst, padata_init_pqueues(pd); padata_init_squeues(pd); - setup_timer(&pd->timer, padata_reorder_timer, (unsigned long)pd); atomic_set(&pd->seq_nr, -1); atomic_set(&pd->reorder_objects, 0); atomic_set(&pd->refcnt, 1); pd->pinst = pinst; spin_lock_init(&pd->lock); + pd->cpu = cpumask_first(pd->cpumask.pcpu); + INIT_WORK(&pd->reorder_work, invoke_padata_reorder); return pd; |