在 2019/11/12 下午10:38, Matthew Wilcox 写道: > On Tue, Nov 12, 2019 at 10:06:26PM +0800, Alex Shi wrote: >> Intel 0day report there are performance regression on this patchset. >> The detailed info points to rcu_read_lock + PROVE_LOCKING which causes >> queued_spin_lock_slowpath waiting too long time to get lock. >> Remove rcu_read_lock is safe here since we had a spinlock hold. > Argh. You have not sent these patches in a properly reviewable form! > I wasted all that time reviewing the earlier patch in this series only to > find out that you changed it here. FIX THE PATCH, don't send a fix-patch > on top of it! > Hi Matthew, Very sorry for your time! The main reasons I use a separate patch since a, Intel 0day asking me to credit their are founding, and I don't know how to give a clearly/elegant explanation for a non-exist regression in a fixed patch. b, this regression is kindly pretty tricky. Maybe it's better saying thanks in version change log of cover-letter? Anyway, Thanks a lot for your review! Alex
