===================================================================
@@ -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
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) {
@@ -363,14 +371,16 @@ static int userspace_flush(struct dm_dir
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;
/*
@@ -380,7 +390,16 @@ static int userspace_flush(struct dm_dir
* 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),
@@ -398,7 +417,11 @@ fail:
* 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);
}
@@ -428,7 +451,7 @@ static void userspace_mark_region(struct
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;
@@ -465,7 +488,7 @@ static void userspace_clear_region(struc
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;