Re: [RFC V4 PATCH] trace: writeback: replace cgroup path to cgroup ino

From: Shi, Yang
Date: Sun Mar 06 2016 - 22:32:41 EST


Hi Steven,

Any comment on this one? I'm supposed it will be taken by your tracing tree?

Thanks,
Yang


On 3/4/2016 4:52 AM, Tejun Heo wrote:
On Thu, Mar 03, 2016 at 01:08:57AM -0800, Yang Shi wrote:
commit 5634cc2aa9aebc77bc862992e7805469dcf83dac ("writeback: update writeback
tracepoints to report cgroup") made writeback tracepoints print out cgroup
path when CGROUP_WRITEBACK is enabled, but it may trigger the below bug on -rt
kernel since kernfs_path and kernfs_path_len are called by tracepoints, which
acquire spin lock that is sleepable on -rt kernel.

Acked-by: Tejun Heo <tj@xxxxxxxxxx>

Thanks.