The donecbs's ->len field is used to store the total count of the segmented
callback list's length. This ->len field is then added to the destination segcb
list.
However, this presents a problem for per-segment length counting which is added
in a future patch. This future patch sets the rcl->len field as we move
segments of callbacks between source and destination lists, thus becoming
incompatible with the donecb's ->len field.
This commit therefore avoids depending on the ->len field in this way. IMHO,
this is also less error-prone and is more accurate - the donecb's ->len field
should be the length of the done segment and not just used as a temporarily
variable.
Signed-off-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx>
---
kernel/rcu/rcu_segcblist.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/kernel/rcu/rcu_segcblist.c b/kernel/rcu/rcu_segcblist.c
index 2d2a6b6b9dfb..b70d4154433c 100644
--- a/kernel/rcu/rcu_segcblist.c
+++ b/kernel/rcu/rcu_segcblist.c
@@ -513,14 +513,18 @@ void rcu_segcblist_merge(struct rcu_segcblist *dst_rsclp,
{
struct rcu_cblist donecbs;
struct rcu_cblist pendcbs;
+ long src_len;
rcu_cblist_init(&donecbs);
rcu_cblist_init(&pendcbs);
- rcu_segcblist_extract_count(src_rsclp, &donecbs);
+
+ src_len = rcu_segcblist_xchg_len(src_rsclp, 0);
rcu_segcblist_extract_done_cbs(src_rsclp, &donecbs);
rcu_segcblist_extract_pend_cbs(src_rsclp, &pendcbs);
- rcu_segcblist_insert_count(dst_rsclp, &donecbs);
+
+ rcu_segcblist_add_len(dst_rsclp, src_len);
rcu_segcblist_insert_done_cbs(dst_rsclp, &donecbs);
rcu_segcblist_insert_pend_cbs(dst_rsclp, &pendcbs);
+
rcu_segcblist_init(src_rsclp);
}
--
2.28.0.297.g1956fa8f8d-goog
