主线补丁回合：block: don't merge across cgroup boundaries if blkcg is enabled

【环境信息】
硬件信息：不涉及
软件信息：OLK-5.10
【问题描述】
主线补丁回合：

blk-iocost and iolatency are cgroup aware rq-qos policies but they didn't
    disable merges across different cgroups. This obviously can lead to
    accounting and control errors but more importantly to priority inversions -
    e.g. an IO which belongs to a higher priority cgroup or IO class may end up
    getting throttled incorrectly because it gets merged to an IO issued from a
    low priority cgroup.

Fix it by adding blk_cgroup_mergeable() which is called from merge paths and
    rejects cross-cgroup and cross-issue_as_root merges.

不在同一个cgroup控制节点下的io进行合并会导致控制效果变差。补丁使得这样的io不合并。

【补丁信息】
    mainline inclusion
    from mainline-v5.18-rc1
    commit 6b2b04590b51aa4cf395fcd185ce439cab5961dc
    category: bugfix
    Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/fs?h=v6.0-rc5&id=6b2b04590b51aa4cf395fcd185ce439cab5961dc

【KABI变更】
    该补丁由于include新的头文件以及在头文件新增函数会导致kabi变更，将新函数以及它会调用的函数bio_issue_as_root_blkg()移到blk-mq.h中。iocost也会调用这个函数，所以在blk-iocost.c中include blk-mq.h

GVP openEuler/kernel

Content Risk Flag

Comments (1)

GVPopenEuler/kernel

Content Risk Flag