On Thu, Aug 20, 2020 at 11:42 PM Jens Axboe <axboe@xxxxxxxxx> wrote: > > On 8/20/20 8:24 PM, Glauber Costa wrote: > > On Thu, Aug 20, 2020 at 9:57 PM Jens Axboe <axboe@xxxxxxxxx> wrote: > >> > >> On 8/20/20 6:46 PM, Glauber Costa wrote: > >>> I have just noticed that the commit in $subject broke the behavior I > >>> introduced in > >>> bf3aeb3dbbd7f41369ebcceb887cc081ffff7b75 > >>> > >>> In this commit, I have explained why and when it does make sense to > >>> enter the ring if there are no sqes to submit. > >>> > >>> I guess one could argue that in that case one could call the system > >>> call directly, but it is nice that the application didn't have to > >>> worry about that, had to take no conditionals, and could just rely on > >>> io_uring_submit as an entry point. > >>> > >>> Since the author is the first to say in the patch that the patch may > >>> not be needed, my opinion is that not only it is not needed but in > >>> fact broke applications that relied on previous behavior on the poll > >>> ring. > >>> > >>> Can we please revert? > >> > >> Yeah let's just revert it for now. Any chance you can turn this into > >> a test case for liburing? Would help us not break this in the future. > > > > would be my pleasure. > > > > Biggest issue is that poll mode really only works with ext4 and xfs as > > far as I know. That may mean it won't get as much coverage, but maybe > > that's not relevant. > > And raw nvme too, of course. But I'd say coverage is pretty decent with > those two, in reality that's most likely what people would use for > polling anyway. So not too concerned about that, and it'll hit multiple > items in my test suite. > > I reverted the change manually, it didn't revert cleanly. Please test > current -git, thanks! > Just tested (through a new unit test) and it works, thanks. I wrote a unit test that works on HEAD but not on HEAD^. However you will have to excuse my lack of manners, but in my new work account I can't have app passwords for GSuite so I am unable to git-send-email it without talking to a host of corporate IT people... I'll have to send a ... urgh... PR > -- > Jens Axboe >
