Jens Axboe
9054650fac
In doing high IOPS testing, blk-mq is generally pretty well optimized. There are a few things that stuck out as using more CPU than what is really warranted, and one thing is the round_jiffies_up() that we do twice for each request. That accounts for about 0.8% of the CPU in my testing. We can make this cheaper by avoiding an integer division, by just adding a rough HZ mask that we can AND with instead. The timeouts are only on a second granularity already, we don't have to be that accurate here and this patch barely changes that. All we care about is nice grouping. Signed-off-by: Jens Axboe <axboe@kernel.dk>
Linux kernel
============
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