From e995d5123ed433e37a8d63ac528737c912592e3d Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Sat, 7 Dec 2019 21:06:46 -0700 Subject: io-wq: briefly spin for new work after finishing work To avoid going to sleep only to get woken shortly thereafter, spin briefly for new work upon completion of work. Signed-off-by: Jens Axboe --- fs/io-wq.h | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'fs/io-wq.h') diff --git a/fs/io-wq.h b/fs/io-wq.h index 7c333a28e2a7..fb993b2bd0ef 100644 --- a/fs/io-wq.h +++ b/fs/io-wq.h @@ -35,7 +35,8 @@ static inline void wq_list_add_tail(struct io_wq_work_node *node, struct io_wq_work_list *list) { if (!list->first) { - list->first = list->last = node; + list->last = node; + WRITE_ONCE(list->first, node); } else { list->last->next = node; list->last = node; @@ -47,7 +48,7 @@ static inline void wq_node_del(struct io_wq_work_list *list, struct io_wq_work_node *prev) { if (node == list->first) - list->first = node->next; + WRITE_ONCE(list->first, node->next); if (node == list->last) list->last = prev; if (prev) @@ -58,7 +59,7 @@ static inline void wq_node_del(struct io_wq_work_list *list, #define wq_list_for_each(pos, prv, head) \ for (pos = (head)->first, prv = NULL; pos; prv = pos, pos = (pos)->next) -#define wq_list_empty(list) ((list)->first == NULL) +#define wq_list_empty(list) (READ_ONCE((list)->first) == NULL) #define INIT_WQ_LIST(list) do { \ (list)->first = NULL; \ (list)->last = NULL; \ -- cgit v1.2.3