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author | Xuan Zhuo <xuanzhuo@linux.alibaba.com> | 2020-06-23 13:34:06 +0200 |
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committer | Jens Axboe <axboe@kernel.dk> | 2020-06-23 19:54:30 +0200 |
commit | b772f07add1c0b22e02c0f1e96f647560679d3a9 (patch) | |
tree | f940038f6a1d4e1f26ed0ea0217a636af4da2b58 /fs/io_uring.c | |
parent | Linux 5.8-rc2 (diff) | |
download | linux-b772f07add1c0b22e02c0f1e96f647560679d3a9.tar.xz linux-b772f07add1c0b22e02c0f1e96f647560679d3a9.zip |
io_uring: fix io_sq_thread no schedule when busy
When the user consumes and generates sqe at a fast rate,
io_sqring_entries can always get sqe, and ret will not be equal to -EBUSY,
so that io_sq_thread will never call cond_resched or schedule, and then
we will get the following system error prompt:
rcu: INFO: rcu_sched self-detected stall on CPU
or
watchdog: BUG: soft lockup-CPU#23 stuck for 112s! [io_uring-sq:1863]
This patch checks whether need to call cond_resched() by checking
the need_resched() function every cycle.
Suggested-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'fs/io_uring.c')
-rw-r--r-- | fs/io_uring.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index a78201b96179..9de9db70b928 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -6011,7 +6011,7 @@ static int io_sq_thread(void *data) * If submit got -EBUSY, flag us as needing the application * to enter the kernel to reap and flush events. */ - if (!to_submit || ret == -EBUSY) { + if (!to_submit || ret == -EBUSY || need_resched()) { /* * Drop cur_mm before scheduling, we can't hold it for * long periods (or over schedule()). Do this before @@ -6027,7 +6027,7 @@ static int io_sq_thread(void *data) * more IO, we should wait for the application to * reap events and wake us up. */ - if (!list_empty(&ctx->poll_list) || + if (!list_empty(&ctx->poll_list) || need_resched() || (!time_after(jiffies, timeout) && ret != -EBUSY && !percpu_ref_is_dying(&ctx->refs))) { if (current->task_works) |