On 2021/5/27 9:01 AM, Bart Van Assche wrote: > Hi Jens, > > A feature that is missing from the Linux kernel for storage devices that > support I/O priorities is to set the I/O priority in requests involving page > cache writeback. Since the identity of the process that triggers page cache > writeback is not known in the writeback code, the priority set by ioprio_set() > is ignored. However, an I/O cgroup is associated with writeback requests > by certain filesystems. Hence this patch series that implements the following > changes for the mq-deadline scheduler: Hi Bart How about implement this feature based on the rq-qos framework ? Maybe it is better to make mq-deadline a pure io-scheduler. Best regards Jianchao > * Make the I/O priority configurable per I/O cgroup. > * Change the I/O priority of requests to the lower of (request I/O priority, > cgroup I/O priority). > * Introduce one queue per I/O priority in the mq-deadline scheduler. > > Please consider this patch series for kernel v5.14. > > Thanks, > > Bart. > > Bart Van Assche (9): > block/mq-deadline: Add several comments > block/mq-deadline: Add two lockdep_assert_held() statements > block/mq-deadline: Remove two local variables > block/mq-deadline: Rename dd_init_queue() and dd_exit_queue() > block/mq-deadline: Improve compile-time argument checking > block/mq-deadline: Reduce the read expiry time for non-rotational > media > block/mq-deadline: Reserve 25% of tags for synchronous requests > block/mq-deadline: Add I/O priority support > block/mq-deadline: Add cgroup support > > block/Kconfig.iosched | 6 + > block/Makefile | 1 + > block/mq-deadline-cgroup.c | 206 +++++++++++++++ > block/mq-deadline-cgroup.h | 73 ++++++ > block/mq-deadline.c | 524 +++++++++++++++++++++++++++++-------- > 5 files changed, 695 insertions(+), 115 deletions(-) > create mode 100644 block/mq-deadline-cgroup.c > create mode 100644 block/mq-deadline-cgroup.h >
