linux-toradex.git/include/linux/hugetlb.h, branch v4.9.14

mm: remove unnecessary condition in remove_inode_hugepages

2016-10-08T01:46:29+00:00

When the huge page is added to the page cahce (huge_add_to_page_cache),
the page private flag will be cleared.  since this code
(remove_inode_hugepages) will only be called for pages in the page
cahce, PagePrivate(page) will always be false.

The patch remove the code without any functional change.

Link: http://lkml.kernel.org/r/1475113323-29368-1-git-send-email-zhongjiang@huawei.com
Signed-off-by: zhong jiang 
Reviewed-by: Naoya Horiguchi 
Reviewed-by: Mike Kravetz 
Tested-by: Mike Kravetz 
Acked-by: Michal Hocko 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/hugetlb: check for reserved hugepages during memory offline

2016-10-08T01:46:29+00:00

In dissolve_free_huge_pages(), free hugepages will be dissolved without
making sure that there are enough of them left to satisfy hugepage
reservations.

Fix this by adding a return value to dissolve_free_huge_pages() and
checking h->free_huge_pages vs.  h->resv_huge_pages.  Note that this may
lead to the situation where dissolve_free_huge_page() returns an error
and all free hugepages that were dissolved before that error are lost,
while the memory block still cannot be set offline.

Fixes: c8721bbb ("mm: memory-hotplug: enable memory hotplug to handle hugepage")
Link: http://lkml.kernel.org/r/20160926172811.94033-3-gerald.schaefer@de.ibm.com
Signed-off-by: Gerald Schaefer 
Acked-by: Michal Hocko 
Acked-by: Naoya Horiguchi 
Cc: "Kirill A . Shutemov" 
Cc: Vlastimil Babka 
Cc: Mike Kravetz 
Cc: "Aneesh Kumar K . V" 
Cc: Martin Schwidefsky 
Cc: Heiko Carstens 
Cc: Rui Teng 
Cc: Dave Hansen 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

include/linux/hugetlb.h: use bool instead of int for hugepage_migration_supported()

2016-05-21T00:58:30+00:00

It is used as a pure bool function within kernel source wide.

Signed-off-by: Chen Gang 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

include/linux/hugetlb*.h: clean up code

2016-05-21T00:58:30+00:00

Macro HUGETLBFS_SB is clear enough, so one statement is clearer than 3
lines statements.

Remove redundant return statements for non-return functions, which can
save lines, at least.

Signed-off-by: Chen Gang 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/hugetlb: introduce hugetlb_bad_size()

2016-05-20T02:12:14+00:00

When any unsupported hugepage size is specified, 'hugepagesz=' and
'hugepages=' should be ignored during command line parsing until any
supported hugepage size is found.  But currently incorrect number of
hugepages are allocated when unsupported size is specified as it fails
to ignore the 'hugepages=' command.

Test case:

Note that this is specific to x86 architecture.

Boot the kernel with command line option 'hugepagesz=256M hugepages=X'.
After boot, dmesg output shows that X number of hugepages of the size 2M
is pre-allocated instead of 0.

So, to handle such command line options, introduce new routine
hugetlb_bad_size.  The routine hugetlb_bad_size sets the global variable
parsed_valid_hugepagesz.  We are using parsed_valid_hugepagesz to save
the state when unsupported hugepagesize is found so that we can ignore
the 'hugepages=' parameters after that and then reset the variable when
supported hugepage size is found.

The routine hugetlb_bad_size can be called while setting 'hugepagesz='
parameter in an architecture specific code.

Signed-off-by: Vaishali Thakkar 
Reviewed-by: Mike Kravetz 
Reviewed-by: Naoya Horiguchi 
Acked-by: Michal Hocko 
Cc: Hillf Danton 
Cc: Yaowei Bai 
Cc: Dominik Dingel 
Cc: Kirill A. Shutemov 
Cc: Paul Gortmaker 
Cc: Dave Hansen 
Cc: Benjamin Herrenschmidt 
Cc: James Hogan 
Cc: Ingo Molnar 
Cc: Thomas Gleixner 
Cc: "H. Peter Anvin" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

hugetlb: fix compile error on tile

2016-01-16T01:56:32+00:00

Inlude asm/pgtable.h to get the definition for pud_t to fix:

  include/linux/hugetlb.h:203:29: error: unknown type name 'pud_t'

Signed-off-by: Dan Williams 
Cc: Liviu Dudau 
Cc: Sudeep Holla 
Cc: Lorenzo Pieralisi 
Cc: David Howells 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

include/linux/hugetlb.h: is_file_hugepages() can be boolean

2016-01-15T00:00:49+00:00

Make is_file_hugepages() return bool to improve readability due to this
particular function only using either one or zero as its return value.

This patch also removed the if condition to make is_file_hugepages
return directly.

No functional change.

Signed-off-by: Yaowei Bai 
Acked-by: Michal Hocko 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

arm64: hugetlb: add support for PTE contiguous bit

2015-12-21T17:26:00+00:00

The arm64 MMU supports a Contiguous bit which is a hint that the TTE
is one of a set of contiguous entries which can be cached in a single
TLB entry.  Supporting this bit adds new intermediate huge page sizes.

The set of huge page sizes available depends on the base page size.
Without using contiguous pages the huge page sizes are as follows.

 4KB:   2MB  1GB
64KB: 512MB

With a 4KB granule, the contiguous bit groups together sets of 16 pages
and with a 64KB granule it groups sets of 32 pages.  This enables two new
huge page sizes in each case, so that the full set of available sizes
is as follows.

 4KB:  64KB   2MB  32MB  1GB
64KB:   2MB 512MB  16GB

If a 16KB granule is used then the contiguous bit groups 128 pages
at the PTE level and 32 pages at the PMD level.

If the base page size is set to 64KB then 2MB pages are enabled by
default.  It is possible in the future to make 2MB the default huge
page size for both 4KB and 64KB granules.

Reviewed-by: Chris Metcalf 
Reviewed-by: Steve Capper 
Signed-off-by: David Woods 
Signed-off-by: Will Deacon

mm: hugetlb: proc: add HugetlbPages field to /proc/PID/status

2015-11-06T03:34:48+00:00

Currently there's no easy way to get per-process usage of hugetlb pages,
which is inconvenient because userspace applications which use hugetlb
typically want to control their processes on the basis of how much memory
(including hugetlb) they use.  So this patch simply provides easy access
to the info via /proc/PID/status.

Signed-off-by: Naoya Horiguchi 
Acked-by: Joern Engel 
Acked-by: David Rientjes 
Acked-by: Michal Hocko 
Cc: Mike Kravetz 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

hugetlbfs: add hugetlbfs_fallocate()

2015-09-08T22:35:28+00:00

This is based on the shmem version, but it has diverged quite a bit.  We
have no swap to worry about, nor the new file sealing.  Add
synchronication via the fault mutex table to coordinate page faults,
fallocate allocation and fallocate hole punch.

What this allows us to do is move physical memory in and out of a
hugetlbfs file without having it mapped.  This also gives us the ability
to support MADV_REMOVE since it is currently implemented using
fallocate().  MADV_REMOVE lets madvise() remove pages from the middle of
a hugetlbfs file, which wasn't possible before.

hugetlbfs fallocate only operates on whole huge pages.

Based on code by Dave Hansen.

Signed-off-by: Mike Kravetz 
Reviewed-by: Naoya Horiguchi 
Acked-by: Hillf Danton 
Cc: Dave Hansen 
Cc: David Rientjes 
Cc: Hugh Dickins 
Cc: Davidlohr Bueso 
Cc: Aneesh Kumar 
Cc: Christoph Hellwig 
Cc: Michal Hocko 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds