Hi Linus, On 2023/1/29 下午3:33, Linus Torvalds wrote:
On Sat, Jan 28, 2023 at 10:05 PM Hongchen Zhang <zhanghongchen@xxxxxxxxxxx> wrote:Use spinlock in pipe_{read,write} cost too much time,IMO pipe->{head,tail} can be protected by __pipe_{lock,unlock}. On the other hand, we can use __pipe_{lock,unlock} to protect the pipe->{head,tail} in pipe_resize_ring and post_one_notification.No, we really can't. post_one_notification() is called under the RCU lock held, *and* with a spinlock held. It simply cannot do a sleeping lock like __pipe_lock(). So that patch is simply fundamentally buggy, I'm afraid. Linus
Thanks for your review,Let me find out if there is any way to solve the problem you said. Best Regards Hongchen Zhang
