From 703fd1c0f177219e3a84e6c095c31dc566514d81 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Fri, 16 Sep 2016 13:59:14 -0600 Subject: blk-mq: account higher order dispatch We currently account a '0' dispatch, and anything above that still falls below the range set by BLK_MQ_MAX_DISPATCH_ORDER. If we dispatch more, we don't account it. Change the last bucket to be inclusive of anything above the range we track, and have the sysfs file reflect that by including a '+' in the output: $ cat /sys/block/nvme0n1/mq/0/dispatched 0 1006 1 20229 2 1 4 0 8 0 16 0 32+ 0 Signed-off-by: Jens Axboe Reviewed-by: Omar Sandoval --- block/blk-mq.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) (limited to 'block/blk-mq.c') diff --git a/block/blk-mq.c b/block/blk-mq.c index 7ddc796..0cb9362 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -789,6 +789,14 @@ static void flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list) } } +static inline unsigned int queued_to_index(unsigned int queued) +{ + if (!queued) + return 0; + + return min(BLK_MQ_MAX_DISPATCH_ORDER - 1, ilog2(queued) + 1); +} + /* * Run this hardware queue, pulling any software queues mapped to it in. * Note that this function currently has various problems around ordering @@ -877,10 +885,7 @@ static void __blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx) dptr = &driver_list; } - if (!queued) - hctx->dispatched[0]++; - else if (queued < (1 << (BLK_MQ_MAX_DISPATCH_ORDER - 1))) - hctx->dispatched[ilog2(queued) + 1]++; + hctx->dispatched[queued_to_index(queued)]++; /* * Any items that need requeuing? Stuff them into hctx->dispatch, -- cgit v1.1