The function padata_reorder will use a timer when it cannot progress while completed jobs are outstanding (pd->reorder_objects > 0). This is suboptimal as if we do end up using the timer then it would have introduced a gratuitous delay of one second. In fact we can easily distinguish between whether completed jobs are outstanding and whether we can make progress. All we have to do is look at the next pqueue list. This patch does that by replacing pd->processed with pd->cpu so that the next pqueue is more accessible. A work queue is used instead of the original try_again to avoid hogging the CPU. Note that we don't bother removing the work queue in padata_flush_queues because the whole premise is broken. You cannot flush async crypto requests so it makes no sense to even try. A subsequent patch will fix it by replacing it with a ref counting scheme.
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| @@ -12,7 +12,6 @@ · 11 unmodified lines | |||
| 12 | #include <linux/workqueue.h> | 12 | #include <linux/workqueue.h> |
| 13 | #include <linux/spinlock.h> | 13 | #include <linux/spinlock.h> |
| 14 | #include <linux/list.h> | 14 | #include <linux/list.h> |
| 15 | #include <linux/timer.h> | ||
| 16 | #include <linux/notifier.h> | 15 | #include <linux/notifier.h> |
| 17 | #include <linux/kobject.h> | 16 | #include <linux/kobject.h> |
| 18 | 17 | ||
| @@ -73,18 +72,14 @@ struct padata_serial_queue { · 54 unmodified lines | |||
| 73 | * @serial: List to wait for serialization after reordering. | 72 | * @serial: List to wait for serialization after reordering. |
| 74 | * @pwork: work struct for parallelization. | 73 | * @pwork: work struct for parallelization. |
| 75 | * @swork: work struct for serialization. | 74 | * @swork: work struct for serialization. |
| 76 | * @pd: Backpointer to the internal control structure. | ||
| 77 | * @work: work struct for parallelization. | 75 | * @work: work struct for parallelization. |
| 78 | * @reorder_work: work struct for reordering. | ||
| 79 | * @num_obj: Number of objects that are processed by this cpu. | 76 | * @num_obj: Number of objects that are processed by this cpu. |
| 80 | * @cpu_index: Index of the cpu. | 77 | * @cpu_index: Index of the cpu. |
| 81 | */ | 78 | */ |
| 82 | struct padata_parallel_queue { | 79 | struct padata_parallel_queue { |
| 83 | struct padata_list parallel; | 80 | struct padata_list parallel; |
| 84 | struct padata_list reorder; | 81 | struct padata_list reorder; |
| 85 | struct parallel_data *pd; | ||
| 86 | struct work_struct work; | 82 | struct work_struct work; |
| 87 | struct work_struct reorder_work; | ||
| 88 | atomic_t num_obj; | 83 | atomic_t num_obj; |
| 89 | int cpu_index; | 84 | int cpu_index; |
| 90 | }; | 85 | }; |
| @@ -110,10 +105,10 @@ struct padata_cpumask { · 19 unmodified lines | |||
| 110 | * @reorder_objects: Number of objects waiting in the reorder queues. | 105 | * @reorder_objects: Number of objects waiting in the reorder queues. |
| 111 | * @refcnt: Number of objects holding a reference on this parallel_data. | 106 | * @refcnt: Number of objects holding a reference on this parallel_data. |
| 112 | * @max_seq_nr: Maximal used sequence number. | 107 | * @max_seq_nr: Maximal used sequence number. |
| 108 | * @cpu: Next CPU to be processed. | ||
| 113 | * @cpumask: The cpumasks in use for parallel and serial workers. | 109 | * @cpumask: The cpumasks in use for parallel and serial workers. |
| 110 | * @reorder_work: work struct for reordering. | ||
| 114 | * @lock: Reorder lock. | 111 | * @lock: Reorder lock. |
| 115 | * @processed: Number of already processed objects. | ||
| 116 | * @timer: Reorder timer. | ||
| 117 | */ | 112 | */ |
| 118 | struct parallel_data { | 113 | struct parallel_data { |
| 119 | struct padata_instance *pinst; | 114 | struct padata_instance *pinst; |
| @@ -122,10 +117,10 @@ struct parallel_data { · 2 unmodified lines | |||
| 122 | atomic_t reorder_objects; | 117 | atomic_t reorder_objects; |
| 123 | atomic_t refcnt; | 118 | atomic_t refcnt; |
| 124 | atomic_t seq_nr; | 119 | atomic_t seq_nr; |
| 120 | int cpu; | ||
| 125 | struct padata_cpumask cpumask; | 121 | struct padata_cpumask cpumask; |
| 122 | struct work_struct reorder_work; | ||
| 126 | spinlock_t lock ____cacheline_aligned; | 123 | spinlock_t lock ____cacheline_aligned; |
| 127 | unsigned int processed; | ||
| 128 | struct timer_list timer; | ||
| 129 | }; | 124 | }; |
| 130 | 125 | ||
| 131 | /** | 126 | /** |