On 1/25/24 16:19, zhaoyang.huang wrote: > From: Zhaoyang Huang <zhaoyang.huang@xxxxxxxxxx> > > Currently, request's ioprio are set via task's schedule priority(when no > blkcg configured), which has high priority tasks possess the privilege on > both of CPU and IO scheduling. > This commit works as a hint of original policy by promoting the request ioprio > based on the page/folio's activity. The original idea comes from LRU_GEN > which provides more precised folio activity than before. This commit try > to adjust the request's ioprio when certain part of its folios are hot, > which indicate that this request carry important contents and need be > scheduled ealier. > > This commit is verified on a v6.6 6GB RAM android14 system via 4 test cases > by changing the bio_add_page/folio API in ext4 and f2fs. And as mentioned already by Chrisoph and Jens, why don't you just simply set bio->bi_ioprio to the value you want before calling submit_bio() in these file systems ? Why all the hacking of the priority code for that ? That is not justified at all. Furthermore, the activity things reduces the ioprio hint bits to the bare minimum 3 bits necessary for command duration limits. Not great. But if you simply set the prio class based on your activity algorithm, you do not need to change all that. Note: Your patch is full of whitespace changes. -- Damien Le Moal Western Digital Research
