On 4/24/25 17:21, Ming Lei wrote:
elevator change is one well-define behavior: - tear down current elevator if it exists - setup new elevator It is supposed to cover any case for changing elevator by single internal API, typically the following cases: - setup default elevator in add_disk() - switch to none in del_disk() - reset elevator in blk_mq_update_nr_hw_queues() - switch elevator in sysfs `store` elevator attribute This patch uses elevator_change() to cover all above cases: - every elevator switch is serialized with each other: add_disk/del_disk/ store elevator is serialized already, blk_mq_update_nr_hw_queues() uses srcu for syncing with the other three cases - for both add_disk()/del_disk(), queue freeze works at atomic mode or has been froze, so the freeze in elevator_change() won't add extra delay - `struct elev_change_ctx` instance holds any info for changing elevator Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx> --- block/blk-sysfs.c | 18 +++----- block/blk.h | 5 +- block/elevator.c | 114 +++++++++++++++++++++++++--------------------- block/genhd.c | 28 ++---------- 4 files changed, 75 insertions(+), 90 deletions(-)
Reviewed-by: Hannes Reinecke <hare@xxxxxxx> Cheers, Hannes -- Dr. Hannes Reinecke Kernel Storage Architect hare@xxxxxxx +49 911 74053 688 SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich
