padata: Add some code comments

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 53 insertions, 0 deletions

diff --git a/include/linux/padata.h b/include/linux/padata.h
index 64836a63bd17..8d8406246eef 100644
--- a/include/linux/padata.h
+++ b/include/linux/padata.h
@@ -26,6 +26,17 @@
 #include <linux/list.h>
 #include <linux/timer.h>
 
+/**
+ * struct padata_priv -  Embedded to the users data structure.
+ *
+ * @list: List entry, to attach to the padata lists.
+ * @pd: Pointer to the internal control structure.
+ * @cb_cpu: Callback cpu for serializatioon.
+ * @seq_nr: Sequence number of the parallelized data object.
+ * @info: Used to pass information from the parallel to the serial function.
+ * @parallel: Parallel execution function.
+ * @serial: Serial complete function.
+ */
 struct padata_priv {
         struct list_head        list;
         struct parallel_data    *pd;
@@ -36,11 +47,29 @@ struct padata_priv {
         void                    (*serial)(struct padata_priv *padata);
 };
 
+/**
+ * struct padata_list
+ *
+ * @list: List head.
+ * @lock: List lock.
+ */
 struct padata_list {
         struct list_head        list;
         spinlock_t              lock;
 };
 
+/**
+ * struct padata_queue - The percpu padata queues.
+ *
+ * @parallel: List to wait for parallelization.
+ * @reorder: List to wait for reordering after parallel processing.
+ * @serial: List to wait for serialization after reordering.
+ * @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 {
         struct padata_list      parallel;
         struct padata_list      reorder;
@@ -52,6 +81,20 @@ struct padata_queue {
         int                     cpu_index;
 };
 
+/**
+ * struct parallel_data - Internal control structure, covers everything
+ * that depends on the cpumask in use.
+ *
+ * @pinst: padata instance.
+ * @queue: percpu padata queues.
+ * @seq_nr: The sequence number that will be attached to the next object.
+ * @reorder_objects: Number of objects waiting in the reorder queues.
+ * @refcnt: Number of objects holding a reference on this parallel_data.
+ * @max_seq_nr:  Maximal used sequence number.
+ * @cpumask: cpumask in use.
+ * @lock: Reorder lock.
+ * @timer: Reorder timer.
+ */
 struct parallel_data {
         struct padata_instance  *pinst;
         struct padata_queue     *queue;
@@ -64,6 +107,16 @@ struct parallel_data {
         struct timer_list       timer;
 };
 
+/**
+ * struct padata_instance - The overall control structure.
+ *
+ * @cpu_notifier: cpu hotplug notifier.
+ * @wq: The workqueue in use.
+ * @pd: The internal control structure.
+ * @cpumask: User supplied cpumask.
+ * @lock: padata instance lock.
+ * @flags: padata flags.
+ */
 struct padata_instance {
         struct notifier_block   cpu_notifier;
         struct workqueue_struct *wq;