Add missing docs about reservation accounting for hugetlb in cgroup v2. Signed-off-by: Odin Ugedal <odin@xxxxxxx> --- RFC: This is linking from cgroup-v1 docs, and that is probably not optimal. The information about the difference between reservation accounting and page fault accounting is pretty hard to make short. I think we have four ways to do it, but I don't know what is most optimal: - Link from cgroup-v2 to cgroup-v1 (this patch) - Have a separate description for both v1 and v2 - Move description from cgroup-v1 to cgroup-v2, and link from v1 to v2. - Move info from cgroup-v1 to admin-guide/mm/hugetlbpage or vm/hugetlbfs_reserv, and link from cgroup to them. admin-guide/cgroup-v1/hugetlb need some formatting anyhow also, will fix that in the same patchset as this. Together with describing <hugepagesize> in cgroup-v2. Documentation/admin-guide/cgroup-v2.rst | 23 +++++++++++++++++++++-- 1 file changed, 21 insertions(+), 2 deletions(-) diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst index 64c62b979f2f..0a29cd46b1ab 100644 --- a/Documentation/admin-guide/cgroup-v2.rst +++ b/Documentation/admin-guide/cgroup-v2.rst @@ -2143,12 +2143,31 @@ RDMA Interface Files HugeTLB ------- -The HugeTLB controller allows to limit the HugeTLB usage per control group and -enforces the controller limit during page fault. +The "HugeTLB" controller regulates usage of huge pages. The controller +supports two forms of accounting: page fault accounting and reservation +accounting. See +:ref:`Documentation/admin-guide/cgroup-v1/hugetlb.rst <cgroup-v1-hugetlb>` +for more details. + HugeTLB Interface Files ~~~~~~~~~~~~~~~~~~~~~~~ + hugetlb.<hugepagesize>.rsvd.current + Show current reservations and no-reserve faults for "hugepagesize" + hugetlb. It exists for all the cgroup except root. + + hugetlb.<hugepagesize>.rsvd.max + Set/show the hard limit of reservations and no-reserve faults for + "hugepagesize" hugetlb. The default value is "max". + It exists for all the cgroup except root. + + hugetlb.<hugepagesize>.rsvd.events + A read-only flat-keyed file which exists on non-root cgroups. + + max + The number of allocation failure due to HugeTLB reservation limit + hugetlb.<hugepagesize>.current Show current usage for "hugepagesize" hugetlb. It exists for all the cgroup except root. -- 2.31.1
