On Mon, Oct 28, 2019 at 11:28 AM Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx> wrote: > > This implements fcntl() for getting amount of resident memory in cache. > Kernel already maintains counter for each inode, this patch just exposes > it into userspace. Returned size is in kilobytes like values in procfs. This doesn't actually explain why anybody would want it, and what the usage scenario is. Linus