On 4/13/21 9:52 PM, Oscar Salvador wrote: > On Tue, Apr 13, 2021 at 03:48:53PM -0700, Mike Kravetz wrote: >> The label free_new is: >> >> free_new: >> spin_unlock_irq(&hugetlb_lock); >> __free_pages(new_page, huge_page_order(h)); >> >> return ret; >> >> So, we are locking and immediately unlocking without any code in >> between. Usually, I don't like like multiple labels before return. >> However, perhaps we should add another to avoid this unnecessary >> cycle. On the other hand, this is an uncommon race condition so the >> simple code may be acceptable. > > I guess we could have something like: > > free_new: > spin_unlock_irq(&hugetlb_lock); > free_new_nolock: > __free_pages(new_page, huge_page_order(h)); > > return ret; > > And let the retry go to there without locking. But as you said, the > racecondition is rare enough, so I am not sure if this buys us much. > But I can certainly add it if you feel strong about it. No strong feelings. I am fine with it as is. -- Mike Kravetz
