From ef67fcb41de6d3d5bbb16aaa66d4c706c4cacf54 Mon Sep 17 00:00:00 2001 From: Dylan Yudaken Date: Mon, 7 Nov 2022 04:33:49 -0800 Subject: [PATCH] io_uring: do not always force run task_work in io_uring_register Running task work when not needed can unnecessarily delay operations. Specifically IORING_SETUP_DEFER_TASKRUN tries to avoid running task work until the user requests it. Therefore do not run it in io_uring_register any more. The one catch is that io_rsrc_ref_quiesce expects it to have run in order to process all outstanding references, and so reorder it's loop to do this. Signed-off-by: Dylan Yudaken Link: https://lore.kernel.org/r/20221107123349.4106213-1-dylany@meta.com Signed-off-by: Jens Axboe --- io_uring/io_uring.c | 2 -- io_uring/rsrc.c | 7 ++++++- 2 files changed, 6 insertions(+), 3 deletions(-) diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index bdb7e15f1c485..cf68d16255a0e 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -4056,8 +4056,6 @@ SYSCALL_DEFINE4(io_uring_register, unsigned int, fd, unsigned int, opcode, ctx = f.file->private_data; - io_run_task_work_ctx(ctx); - mutex_lock(&ctx->uring_lock); ret = __io_uring_register(ctx, opcode, arg, nr_args); mutex_unlock(&ctx->uring_lock); diff --git a/io_uring/rsrc.c b/io_uring/rsrc.c index 55d4ab96fb925..187f1c83e7798 100644 --- a/io_uring/rsrc.c +++ b/io_uring/rsrc.c @@ -321,6 +321,11 @@ __cold static int io_rsrc_ref_quiesce(struct io_rsrc_data *data, if (atomic_dec_and_test(&data->refs)) break; mutex_unlock(&ctx->uring_lock); + + ret = io_run_task_work_sig(ctx); + if (ret < 0) + goto reinit; + flush_delayed_work(&ctx->rsrc_put_work); ret = wait_for_completion_interruptible(&data->done); if (!ret) { @@ -336,12 +341,12 @@ __cold static int io_rsrc_ref_quiesce(struct io_rsrc_data *data, } } +reinit: atomic_inc(&data->refs); /* wait for all works potentially completing data->done */ flush_delayed_work(&ctx->rsrc_put_work); reinit_completion(&data->done); - ret = io_run_task_work_sig(ctx); mutex_lock(&ctx->uring_lock); } while (ret >= 0); data->quiesce = false; -- 2.30.2