On Tue, 23 Jul 2019 15:49:32 +0300 Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx> wrote: > Currently /sys/kernel/debug/bdi/$maj:$min/stats shows only root bdi wb. > With CONFIG_CGROUP_WRITEBACK=y there is one for each memory cgroup. > > This patch shows here state of each bdi_writeback in form: > > <global state> > > Id: 1 > Cgroup: / > <root wb state> > > Id: xxx > Cgroup: /path > <cgroup wb state> > > Id: yyy > Cgroup: /path2 > <cgroup wb state> Why is this considered useful? What are the use cases. ie, why should we add this to Linux? > mm/backing-dev.c | 106 +++++++++++++++++++++++++++++++++++++++++++++++------- > 1 file changed, 93 insertions(+), 13 deletions(-) No documentation because it's debugfs, right? I'm struggling to understand why this is a good thing :(. If it's there and people use it then we should document it for them. If it's there and people don't use it then we should delete the code.
