On Mon, Apr 4, 2022 at 10:08 AM Shakeel Butt <shakeelb@xxxxxxxxxx> wrote: > > On Fri, Apr 1, 2022 at 1:14 PM Wei Xu <weixugc@xxxxxxxxxx> wrote: > > > [...] > > > > -EAGAIN sounds good, too. Given that the userspace requests to > > reclaim a specified number of bytes, I think it is generally better to > > tell the userspace whether the request has been successfully > > fulfilled. Ideally, it would be even better to return how many bytes > > that have been reclaimed, though that is not easy to do through the > > cgroup interface. > > What would be the challenge on returning the number of bytes reclaimed > through cgroup interface? write() syscall is used to write the command into memory.reclaim, which should return either the number of command bytes written or -1 (errno is set to indicate the actual error). I think we should not return the number of bytes reclaimed through write(). A new sys_reclaim() is better in this regard because we can define its return value, though it would need a cgroup argument, which is not commonly defined for syscalls.
