[PATCH 01/12] io_uring: keep SQ pointers in a single cacheline

Pavel Begunkov
2021-06-14T22:38:11Z

sq_array and sq_sqes are always used together, however they are in
different cachelines, where the borderline is right before
cq_overflow_list is rather rarely touched. Move the fields together so
it loads only one cacheline.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
fs/io_uring.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index d665c9419ad3..f3c827cd8ff8 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -364,6 +364,7 @@ struct io_ring_ctx {
* array.
*/
u32 *sq_array;
+ struct io_uring_sqe *sq_sqes;
unsigned cached_sq_head;
unsigned sq_entries;
unsigned sq_thread_idle;
@@ -373,8 +374,6 @@ struct io_ring_ctx {
struct list_head defer_list;
struct list_head timeout_list;
struct list_head cq_overflow_list;
-
- struct io_uring_sqe *sq_sqes;
} ____cacheline_aligned_in_smp;

struct {
--
2.31.1