---

yaml
---
r: 230669
b: refs/heads/master
c: 909cc4f
h: refs/heads/master
i:
  230667: 8383e89
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 8d35d3e37eed884ba15229a146df846f399909b4
+refs/heads/master: 909cc4fb48dd9870f6ebe4bd32cfbe37c102df62

trunk/drivers/md/dm-log-userspace-base.c

@@ -37,8 +37,15 @@ struct log_c {
 	 */
 	uint64_t in_sync_hint;
 
+	/*
+	 * Mark and clear requests are held until a flush is issued
+	 * so that we can group, and thereby limit, the amount of
+	 * network traffic between kernel and userspace.  The 'flush_lock'
+	 * is used to protect these lists.
+	 */
 	spinlock_t flush_lock;
-	struct list_head flush_list;  /* only for clear and mark requests */
+	struct list_head mark_list;
+	struct list_head clear_list;
 };
 
 static mempool_t *flush_entry_pool;
@@ -169,7 +176,8 @@ static int userspace_ctr(struct dm_dirty_log *log, struct dm_target *ti,
 
 	strncpy(lc->uuid, argv[0], DM_UUID_LEN);
 	spin_lock_init(&lc->flush_lock);
-	INIT_LIST_HEAD(&lc->flush_list);
+	INIT_LIST_HEAD(&lc->mark_list);
+	INIT_LIST_HEAD(&lc->clear_list);
 
 	str_size = build_constructor_string(ti, argc - 1, argv + 1, &ctr_str);
 	if (str_size < 0) {
@@ -362,14 +370,16 @@ static int userspace_flush(struct dm_dirty_log *log)
 	int r = 0;
 	unsigned long flags;
 	struct log_c *lc = log->context;
-	LIST_HEAD(flush_list);
+	LIST_HEAD(mark_list);
+	LIST_HEAD(clear_list);
 	struct flush_entry *fe, *tmp_fe;
 
 	spin_lock_irqsave(&lc->flush_lock, flags);
-	list_splice_init(&lc->flush_list, &flush_list);
+	list_splice_init(&lc->mark_list, &mark_list);
+	list_splice_init(&lc->clear_list, &clear_list);
 	spin_unlock_irqrestore(&lc->flush_lock, flags);
 
-	if (list_empty(&flush_list))
+	if (list_empty(&mark_list) && list_empty(&clear_list))
 		return 0;
 
 	/*
@@ -379,7 +389,16 @@ static int userspace_flush(struct dm_dirty_log *log)
 	 * do it one by one.
 	 */
 
-	list_for_each_entry(fe, &flush_list, list) {
+	list_for_each_entry(fe, &mark_list, list) {
+		r = userspace_do_request(lc, lc->uuid, fe->type,
+					 (char *)&fe->region,
+					 sizeof(fe->region),
+					 NULL, NULL);
+		if (r)
+			goto fail;
+	}
+
+	list_for_each_entry(fe, &clear_list, list) {
 		r = userspace_do_request(lc, lc->uuid, fe->type,
 					 (char *)&fe->region,
 					 sizeof(fe->region),
@@ -397,7 +416,11 @@ static int userspace_flush(struct dm_dirty_log *log)
 	 * Calling code will receive an error and will know that
 	 * the log facility has failed.
 	 */
-	list_for_each_entry_safe(fe, tmp_fe, &flush_list, list) {
+	list_for_each_entry_safe(fe, tmp_fe, &mark_list, list) {
+		list_del(&fe->list);
+		mempool_free(fe, flush_entry_pool);
+	}
+	list_for_each_entry_safe(fe, tmp_fe, &clear_list, list) {
 		list_del(&fe->list);
 		mempool_free(fe, flush_entry_pool);
 	}
@@ -427,7 +450,7 @@ static void userspace_mark_region(struct dm_dirty_log *log, region_t region)
 	spin_lock_irqsave(&lc->flush_lock, flags);
 	fe->type = DM_ULOG_MARK_REGION;
 	fe->region = region;
-	list_add(&fe->list, &lc->flush_list);
+	list_add(&fe->list, &lc->mark_list);
 	spin_unlock_irqrestore(&lc->flush_lock, flags);
 
 	return;
@@ -464,7 +487,7 @@ static void userspace_clear_region(struct dm_dirty_log *log, region_t region)
 	spin_lock_irqsave(&lc->flush_lock, flags);
 	fe->type = DM_ULOG_CLEAR_REGION;
 	fe->region = region;
-	list_add(&fe->list, &lc->flush_list);
+	list_add(&fe->list, &lc->clear_list);
 	spin_unlock_irqrestore(&lc->flush_lock, flags);
 
 	return;