From 215c39026023dbfb4026b670c318371252be909f Mon Sep 17 00:00:00 2001 From: Pavel Begunkov Date: Thu, 1 Apr 2021 15:43:48 +0100 Subject: [PATCH] io_uring: remove useless is_dying check on quiesce rsrc_data refs should always be valid for potential submitters, io_rsrc_ref_quiesce() restores it before unlocking, so percpu_ref_is_dying() check in io_sqe_files_unregister() does nothing and misleading. Concurrent quiesce is prevented with struct io_rsrc_data::quiesce. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/bf97055e1748ee3a382e66daf384a469eb90b931.1617287883.git.asml.silence@gmail.com Signed-off-by: Jens Axboe --- fs/io_uring.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 59e666151754a..373fe2b9e1f28 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -7135,6 +7135,7 @@ static int io_rsrc_ref_quiesce(struct io_rsrc_data *data, struct io_ring_ctx *ct { int ret; + /* As we may drop ->uring_lock, other task may have started quiesce */ if (data->quiesce) return -ENXIO; @@ -7197,12 +7198,7 @@ static int io_sqe_files_unregister(struct io_ring_ctx *ctx) unsigned nr_tables, i; int ret; - /* - * percpu_ref_is_dying() is to stop parallel files unregister - * Since we possibly drop uring lock later in this function to - * run task work. - */ - if (!data || percpu_ref_is_dying(&data->refs)) + if (!data) return -ENXIO; ret = io_rsrc_ref_quiesce(data, ctx); if (ret) -- 2.30.2