tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge branch 'for-2.6.38/rc2-holder' into for-2.6.38/core
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-4
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Documentation/cgroups/blkio-controller.txt
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Documentation/cgroups/blkio-controller.txt
···
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Limits for writes can be put using blkio.write_bps_device file.
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Hierarchical Cgroups
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====================
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- Currently none of the IO control policy supports hierarhical groups. But
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cgroup interface does allow creation of hierarhical cgroups and internally
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IO policies treat them as flat hierarchy.
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So this patch will allow creation of cgroup hierarhcy but at the backend
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everything will be treated as flat. So if somebody created a hierarchy like
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as follows.
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root
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/ \
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test1 test2
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|
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test3
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CFQ and throttling will practically treat all groups at same level.
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pivot
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/ | \ \
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root test1 test2 test3
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Down the line we can implement hierarchical accounting/control support
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and also introduce a new cgroup file "use_hierarchy" which will control
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whether cgroup hierarchy is viewed as flat or hierarchical by the policy..
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This is how memory controller also has implemented the things.
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Various user visible config options
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===================================
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CONFIG_BLK_CGROUP
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block/blk-cgroup.c
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block/blk-cgroup.c
···
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goto done;
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}
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-
/* Currently we do not support hierarchy deeper than two level (0,1) */
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-
if (parent != cgroup->top_cgroup)
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-
return ERR_PTR(-EPERM);
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-
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blkcg = kzalloc(sizeof(*blkcg), GFP_KERNEL);
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if (!blkcg)
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return ERR_PTR(-ENOMEM);