From 89448c47b8452b67c146dc6cad6f737e004c5caf Mon Sep 17 00:00:00 2001 From: Pavel Begunkov Date: Thu, 17 Dec 2020 00:24:39 +0000 Subject: io_uring: limit {io|sq}poll submit locking scope We don't need to take uring_lock for SQPOLL|IOPOLL to do io_cqring_overflow_flush() when cq_overflow_list is empty, remove it from the hot path. Signed-off-by: Pavel Begunkov Signed-off-by: Jens Axboe --- fs/io_uring.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) (limited to 'fs/io_uring.c') diff --git a/fs/io_uring.c b/fs/io_uring.c index 5c9aa8b5e077..8cf6f22afc5e 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -9154,10 +9154,13 @@ SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit, */ ret = 0; if (ctx->flags & IORING_SETUP_SQPOLL) { - io_ring_submit_lock(ctx, (ctx->flags & IORING_SETUP_IOPOLL)); - if (!list_empty_careful(&ctx->cq_overflow_list)) + if (!list_empty_careful(&ctx->cq_overflow_list)) { + bool needs_lock = ctx->flags & IORING_SETUP_IOPOLL; + + io_ring_submit_lock(ctx, needs_lock); io_cqring_overflow_flush(ctx, false, NULL, NULL); - io_ring_submit_unlock(ctx, (ctx->flags & IORING_SETUP_IOPOLL)); + io_ring_submit_unlock(ctx, needs_lock); + } if (flags & IORING_ENTER_SQ_WAKEUP) wake_up(&ctx->sq_data->wait); if (flags & IORING_ENTER_SQ_WAIT) -- cgit v1.2.3