From: Tao Cui <[email protected]> Add the bpf_cost_model field to struct ioc and the dispatch hook in calc_vtime_cost(): when a BPF model is registered and the device has opted in (bpf_cost_model set), call the model's calc_cost instead of the builtin formula. If no model is registered anymore the builtin formula is used as fallback.
The user interface to set bpf_cost_model follows. Signed-off-by: Tao Cui <[email protected]> --- block/blk-iocost.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/block/blk-iocost.c b/block/blk-iocost.c index c24daa9d72ee9..bdb4bab86a116 100644 --- a/block/blk-iocost.c +++ b/block/blk-iocost.c @@ -177,6 +177,7 @@ #include <linux/timer.h> #include <linux/time64.h> #include <linux/parser.h> +#include <linux/blk-iocost.h> #include <linux/sched/signal.h> #include <asm/local.h> #include <asm/local64.h> @@ -445,6 +446,7 @@ struct ioc { int autop_idx; bool user_qos_params:1; bool user_cost_model:1; + bool bpf_cost_model; }; struct iocg_pcpu_stat { @@ -2578,6 +2580,23 @@ static u64 calc_vtime_cost(struct bio *bio, struct ioc_gq *iocg, bool is_merge) { u64 cost; +#ifdef CONFIG_BLK_CGROUP_IOCOST_BPF + struct ioc *ioc = iocg->ioc; + + if (READ_ONCE(ioc->bpf_cost_model)) { + u64 bpf_cost; + + if (iocost_bpf_calc_cost(bio_op(bio), + bio->bi_iter.bi_size, + bio->bi_iter.bi_sector, + iocg->cursor, + iocg_to_blkg(iocg)->blkcg->css.id, + is_merge ? IOCOST_COST_F_MERGE : 0, + &bpf_cost)) + return bpf_cost; + } +#endif + calc_vtime_cost_builtin(bio, iocg, is_merge, &cost); return cost; } -- 2.43.0
