70e59a7528
Previously we had a situation where shmem mTHP controls and stats were not exposed for some supported sizes and were exposed for some unsupported sizes. So let's clean that up. Anon mTHP can support all large orders [2, PMD_ORDER]. But shmem can support all large orders [1, MAX_PAGECACHE_ORDER]. However, per-size shmem controls and stats were previously being exposed for all the anon mTHP orders, meaning order-1 was not present, and for arm64 64K base pages, orders 12 and 13 were exposed but were not supported internally. Tidy this all up by defining ctrl and stats attribute groups for anon and file separately. Anon ctrl and stats groups are populated for all orders in THP_ORDERS_ALL_ANON and file ctrl and stats groups are populated for all orders in THP_ORDERS_ALL_FILE_DEFAULT. Additionally, create "any" ctrl and stats attribute groups which are populated for all orders in (THP_ORDERS_ALL_ANON | THP_ORDERS_ALL_FILE_DEFAULT). swpout stats use this since they apply to anon and shmem. The side-effect of all this is that different hugepage-*kB directories contain different sets of controls and stats, depending on which memory types support that size. This approach is preferred over the alternative, which is to populate dummy controls and stats for memory types that do not support a given size. [ryan.roberts@arm.com: file pages and shmem can also be split] Link: https://lkml.kernel.org/r/f7ced14c-8bc5-405f-bee7-94f63980f525@arm.comLink: https://lkml.kernel.org/r/20240808111849.651867-3-ryan.roberts@arm.com Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Tested-by: Barry Song <baohua@kernel.org> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: David Hildenbrand <david@redhat.com> Cc: Gavin Shan <gshan@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Lance Yang <ioworker0@gmail.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.