mm/hugetlb: add folio support to hugetlb specific flag macros

Patch series "begin converting hugetlb code to folios", v4.

This patch series starts the conversion of the hugetlb code to operate on
struct folios rather than struct pages.  This removes the ambiguitiy of
whether functions are operating on head pages, tail pages of compound
pages, or base pages.  

This series passes the linux test project hugetlb test cases.

Patch 1 adds hugeltb specific page macros that can operate on folios.

Patch 2 adds the private field of the first tail page to struct page.  For
32-bit, _private_1 alinging with page[1].private was confirmed by using
pahole.

Patch 3 introduces hugetlb subpool helper functions which operate on
struct folios. These patches were tested using the hugepage-mmap.c
selftest along with the migratepages command.

Patch 4 converts hugetlb_delete_from_page_cache() to use folios.

Patch 5 adds a folio_hstate() function to get hstate information from a
folio and adds a user of folio_hstate().

Bpftrace was used to track time spent in the free_huge_pages function
during the ltp test cases as it is a caller of the hugetlb subpool
functions. From the histogram, the performance is similar before and
after the patch series. 

Time spent in 'free_huge_page'

6.0.0-rc2.master.20220823
@nsecs:
[256, 512)         14770 |@@@@@@@@@@@@@@@@@@@@@@@@@@@
			 |@@@@@@@@@@@@@@@@@@@@@@@@@			      |
[512, 1K)            155 |                                                    |
[1K, 2K)             169 |                                                    |
[2K, 4K)              50 |                                                    |
[4K, 8K)              14 |                                                    |
[8K, 16K)              3 |                                                    |
[16K, 32K)             3 |                                                    |


6.0.0-rc2.master.20220823 + patch series
@nsecs:
[256, 512)         13678 |@@@@@@@@@@@@@@@@@@@@@@@@@@@			      |
			 |@@@@@@@@@@@@@@@@@@@@@@@@@			      |
[512, 1K)            142 |                                                    |
[1K, 2K)             199 |                                                    |
[2K, 4K)              44 |                                                    |
[4K, 8K)              13 |                                                    |
[8K, 16K)              4 |                                                    |
[16K, 32K)             1 |                                                    |


This patch (of 5):

Allow the macros which test, set, and clear hugetlb specific page flags to
take a hugetlb folio as an input.  The macrros are generated as
folio_{test, set, clear}_hugetlb_{restore_reserve, migratable, temporary,
freed, vmemmap_optimized, raw_hwp_unreliable}.

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Sidhartha Kumar <[email protected]>
Reviewed-by: Mike Kravetz <[email protected]>
Reviewed-by: Muchun Song <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Colin Cross <[email protected]>
Cc: David Howells <[email protected]>
Cc: "Eric W . Biederman" <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: kernel test robot <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Peter Xu <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: William Kucharski <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

0 files changed, 0 insertions, 0 deletions