io_uring: move iopoll ctx fields around

Move poll_multi_queue and iopoll_list to the submission cache line, it
doesn't make much sense to keep them separately, and is better place
for it in general.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/5b03cf7e6652e350e6e70a917eec72ba9f33b97b.1692916914.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/include/linux/io_uring_types.h b/include/linux/io_uring_types.h
index 01bdbc2..13d19b9 100644 (file)
--- a/include/linux/io_uring_types.h
+++ b/include/linux/io_uring_types.h
@@ -256,6 +256,15 @@ struct io_ring_ctx {
                struct io_hash_table    cancel_table_locked;
                struct io_alloc_cache   apoll_cache;
                struct io_alloc_cache   netmsg_cache;
+
+               /*
+                * ->iopoll_list is protected by the ctx->uring_lock for
+                * io_uring instances that don't use IORING_SETUP_SQPOLL.
+                * For SQPOLL, only the single threaded io_sq_thread() will
+                * manipulate the list, hence no extra locking is needed there.
+                */
+               struct io_wq_work_list  iopoll_list;
+               bool                    poll_multi_queue;
        } ____cacheline_aligned_in_smp;
 
        struct {
@@ -284,20 +293,6 @@ struct io_ring_ctx {
                struct wait_queue_head  cq_wait;
        } ____cacheline_aligned_in_smp;
 
-       struct {
-               spinlock_t              completion_lock;
-
-               bool                    poll_multi_queue;
-
-               /*
-                * ->iopoll_list is protected by the ctx->uring_lock for
-                * io_uring instances that don't use IORING_SETUP_SQPOLL.
-                * For SQPOLL, only the single threaded io_sq_thread() will
-                * manipulate the list, hence no extra locking is needed there.
-                */
-               struct io_wq_work_list  iopoll_list;
-       } ____cacheline_aligned_in_smp;
-
        /* timeouts */
        struct {
                spinlock_t              timeout_lock;
@@ -308,6 +303,8 @@ struct io_ring_ctx {
 
        struct io_uring_cqe     completion_cqes[16];
 
+       spinlock_t              completion_lock;
+
        /* IRQ completion list, under ->completion_lock */
        struct io_wq_work_list  locked_free_list;
        unsigned int            locked_free_nr;