From mboxrd@z Thu Jan 1 00:00:00 1970 From: Zach Brown Subject: Re: [PATCH 2/5] aio: kiocb_cancel() Date: Wed, 10 Oct 2012 14:20:51 -0700 Message-ID: <20121010212051.GD6371@lenny.home.zabbo.net> References: <1349764760-21093-1-git-send-email-koverstreet@google.com> <1349764760-21093-2-git-send-email-koverstreet@google.com> <20121009182625.GM26187@lenny.home.zabbo.net> <20121009213700.GF29494@google.com> <20121010110356.GA11468@thunk.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20121010110356.GA11468-AKGzg7BKzIDYtjvyW6yDsg@public.gmane.org> Sender: linux-bcache-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Theodore Ts'o , Kent Overstreet , linux-bcache-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, dm-devel-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org List-Id: linux-bcache@vger.kernel.org > And maybe the current way of doing things isn't the best way. But it > would be nice if we didn't completely give up on the functionality of > aio_cancel. I sympathize, but the reality is that the current infrastructure is very bad and no one is using it. It's not like we're getting rid of the syscall. I'll be behaving exactly as it does today: returning the error code that indicates that cancellation failed because it lost the race with completion. Every caller has to cope with that to use cancel safely. So if someone eventually implements iocb cancel safely we'll be able to plumb it back under the aio syscalls. But until that day I see no reason to carry around buggy infrastructure that is only slowing down the fast path. - z