On 15/04/2021 14:59, Jens Axboe wrote: > On 4/15/21 6:40 AM, Pavel Begunkov wrote: >> Not submitting when have requests in overflow backlog looks artificial, >> and limits users for no clear purpose, especially since requests with >> resources are now not locked into it but it consists for a small memory >> area. Remove the restriction. >> >> Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx> >> --- >> >> Mainly for discussion. It breaks several tests, and so in theory >> userspace, but can't think this restriction not being just a >> nuisance to the userspace. IMHO much more convenient to allow it, >> userspace can take care of it itself if needed, but for those >> who don't care and use rings in parallel (e.g. different threads >> for submission and completion), it will be hell of a synchronisation. > > I think we can kill it, with the main change enabling that being the > cgroup memory accounting. This was kind of a safe guard to avoid having Yeah, and not keeping requests, its resources and linking requests. > silly cases just go way overboard, but I do agree that this is really > up to the application to manage. And it may have an easier time doing > so without -EBUSY on overflow being set on submit. Btw, apparently that's the main reason for getting -EBUSY in mshot test, just another lackmustest that it's not convenient. -- Pavel Begunkov
