The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 4a0fef62788b69df09267c8e3f3f11d4bb9d50e7 Mon Sep 17 00:00:00 2001 From: Pavel Begunkov asml.silence@gmail.com Date: Mon, 20 Jun 2022 15:27:35 +0100 Subject: [PATCH] io_uring: optimize io_uring_task layout
task_work bits of io_uring_task are split into two cache lines causing extra cache bouncing, place them into a separate cache line. Also move the most used submission path fields closer together, so there are hot.
Cc: stable@vger.kernel.org # 5.15+ Signed-off-by: Pavel Begunkov asml.silence@gmail.com Signed-off-by: Jens Axboe axboe@kernel.dk
diff --git a/io_uring/tctx.h b/io_uring/tctx.h index dde82ce4d8e2..dead0ed00429 100644 --- a/io_uring/tctx.h +++ b/io_uring/tctx.h @@ -7,22 +7,24 @@
struct io_uring_task { /* submission side */ - int cached_refs; - struct xarray xa; - struct wait_queue_head wait; - const struct io_ring_ctx *last; - struct io_wq *io_wq; - struct percpu_counter inflight; - atomic_t inflight_tracked; - atomic_t in_idle; - - spinlock_t task_lock; - struct io_wq_work_list task_list; - struct io_wq_work_list prio_task_list; - struct callback_head task_work; - bool task_running; - - struct file *registered_rings[IO_RINGFD_REG_MAX]; + int cached_refs; + const struct io_ring_ctx *last; + struct io_wq *io_wq; + struct file *registered_rings[IO_RINGFD_REG_MAX]; + + struct xarray xa; + struct wait_queue_head wait; + atomic_t in_idle; + atomic_t inflight_tracked; + struct percpu_counter inflight; + + struct { /* task_work */ + spinlock_t task_lock; + bool task_running; + struct io_wq_work_list task_list; + struct io_wq_work_list prio_task_list; + struct callback_head task_work; + } ____cacheline_aligned_in_smp; };
struct io_tctx_node {