On Sun, Sep 19, 2021 at 10:41:46AM -0400, Hamza Mahfooz wrote: > Commit 833f4154ed56 ("aio: fold lookup_kiocb() into its sole caller") > suggests that, the fact that active_reqs is a linked-list means aio_kiocb > lookups in io_cancel() are inefficient. So, to get faster lookups (on > average) while maintaining similar insertion and deletion characteristics, > turn active_reqs into a hashtable. You're doing this wrong. If you want faster cancellations, stash an index into iocb->aio_key to index into an array with all requests rather than using a hash table. -ben -- "Thought is the essence of where you are now."