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-rw-r--r--include/linux/padata.h6
-rw-r--r--kernel/padata.c71
2 files changed, 22 insertions, 55 deletions
diff --git a/include/linux/padata.h b/include/linux/padata.h
index e4c17f9b7c9..8844b851191 100644
--- a/include/linux/padata.h
+++ b/include/linux/padata.h
@@ -67,7 +67,6 @@ struct padata_list {
* @pwork: work struct for parallelization.
* @swork: work struct for serialization.
* @pd: Backpointer to the internal control structure.
- * @num_obj: Number of objects that are processed by this cpu.
* @cpu_index: Index of the cpu.
*/
struct padata_queue {
@@ -77,7 +76,6 @@ struct padata_queue {
struct work_struct pwork;
struct work_struct swork;
struct parallel_data *pd;
- atomic_t num_obj;
int cpu_index;
};
@@ -93,6 +91,7 @@ struct padata_queue {
* @max_seq_nr: Maximal used sequence number.
* @cpumask: cpumask in use.
* @lock: Reorder lock.
+ * @processed: Number of already processed objects.
* @timer: Reorder timer.
*/
struct parallel_data {
@@ -103,7 +102,8 @@ struct parallel_data {
atomic_t refcnt;
unsigned int max_seq_nr;
cpumask_var_t cpumask;
- spinlock_t lock;
+ spinlock_t lock ____cacheline_aligned;
+ unsigned int processed;
struct timer_list timer;
};
diff --git a/kernel/padata.c b/kernel/padata.c
index ae8defcf062..450d67d394b 100644
--- a/kernel/padata.c
+++ b/kernel/padata.c
@@ -170,79 +170,47 @@ EXPORT_SYMBOL(padata_do_parallel);
*/
static struct padata_priv *padata_get_next(struct parallel_data *pd)
{
- int cpu, num_cpus, empty, calc_seq_nr;
- int seq_nr, next_nr, overrun, next_overrun;
+ int cpu, num_cpus;
+ int next_nr, next_index;
struct padata_queue *queue, *next_queue;
struct padata_priv *padata;
struct padata_list *reorder;
- empty = 0;
- next_nr = -1;
- next_overrun = 0;
- next_queue = NULL;
-
num_cpus = cpumask_weight(pd->cpumask);
- for_each_cpu(cpu, pd->cpumask) {
- queue = per_cpu_ptr(pd->queue, cpu);
- reorder = &queue->reorder;
-
- /*
- * Calculate the seq_nr of the object that should be
- * next in this reorder queue.
- */
- overrun = 0;
- calc_seq_nr = (atomic_read(&queue->num_obj) * num_cpus)
- + queue->cpu_index;
-
- if (unlikely(calc_seq_nr > pd->max_seq_nr)) {
- calc_seq_nr = calc_seq_nr - pd->max_seq_nr - 1;
- overrun = 1;
- }
-
- if (!list_empty(&reorder->list)) {
- padata = list_entry(reorder->list.next,
- struct padata_priv, list);
-
- seq_nr = padata->seq_nr;
- BUG_ON(calc_seq_nr != seq_nr);
- } else {
- seq_nr = calc_seq_nr;
- empty++;
- }
-
- if (next_nr < 0 || seq_nr < next_nr
- || (next_overrun && !overrun)) {
- next_nr = seq_nr;
- next_overrun = overrun;
- next_queue = queue;
- }
+ /*
+ * 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->queue, cpu);
+
+ if (unlikely(next_nr > pd->max_seq_nr)) {
+ next_nr = next_nr - pd->max_seq_nr - 1;
+ next_index = next_nr % num_cpus;
+ cpu = padata_index_to_cpu(pd, next_index);
+ next_queue = per_cpu_ptr(pd->queue, cpu);
+ pd->processed = 0;
}
padata = NULL;
- if (empty == num_cpus)
- goto out;
-
reorder = &next_queue->reorder;
if (!list_empty(&reorder->list)) {
padata = list_entry(reorder->list.next,
struct padata_priv, list);
- if (unlikely(next_overrun)) {
- for_each_cpu(cpu, pd->cpumask) {
- queue = per_cpu_ptr(pd->queue, cpu);
- atomic_set(&queue->num_obj, 0);
- }
- }
+ BUG_ON(next_nr != padata->seq_nr);
spin_lock(&reorder->lock);
list_del_init(&padata->list);
atomic_dec(&pd->reorder_objects);
spin_unlock(&reorder->lock);
- atomic_inc(&next_queue->num_obj);
+ pd->processed++;
goto out;
}
@@ -430,7 +398,6 @@ static struct parallel_data *padata_alloc_pd(struct padata_instance *pinst,
INIT_WORK(&queue->pwork, padata_parallel_worker);
INIT_WORK(&queue->swork, padata_serial_worker);
- atomic_set(&queue->num_obj, 0);
}
num_cpus = cpumask_weight(pd->cpumask);