When userfaultfd hugetlbfs support was originally added, it followed the
pattern of anon mappings and did not support any vmas marked VM_SHARED.
As such, support was only added for private mappings.
Remove this limitation and support shared mappings. The primary
functional change required is adding pages to the page cache. More subtle
changes are required for huge page reservation handling in error paths. A
lengthy comment in the code describes the reservation handling.
[mike.kravetz@oracle.com: update]
Link: http://lkml.kernel.org/r/c9c8cafe-baa7-05b4-34ea-1dfa5523a85f@oracle.com
Link: http://lkml.kernel.org/r/1487195210-12839-1-git-send-email-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add support for VM_FAULT_RETRY to follow_hugetlb_page() so that
get_user_pages_unlocked/locked and "nonblocking/FOLL_NOWAIT" features
will work on hugetlbfs.
This is required for fully functional userfaultfd non-present support on
hugetlbfs.
Link: http://lkml.kernel.org/r/20161216144821.5183-25-aarcange@redhat.com
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Michael Rapoport <RAPOPORT@il.ibm.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When processing a hugetlb fault for no page present, check the vma to
determine if faults are to be handled via userfaultfd. If so, drop the
hugetlb_fault_mutex and call handle_userfault().
Link: http://lkml.kernel.org/r/20161216144821.5183-21-aarcange@redhat.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Michael Rapoport <RAPOPORT@il.ibm.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The new routine copy_huge_page_from_user() uses kmap_atomic() to map
PAGE_SIZE pages. However, this prevents page faults in the subsequent
call to copy_from_user(). This is OK in the case where the routine is
copied with mmap_sema held. However, in another case we want to allow
page faults. So, add a new argument allow_pagefault to indicate if the
routine should allow page faults.
[dan.carpenter@oracle.com: unmap the correct pointer]
Link: http://lkml.kernel.org/r/20170113082608.GA3548@mwanda
[akpm@linux-foundation.org: kunmap() takes a page*, per Hugh]
Link: http://lkml.kernel.org/r/20161216144821.5183-20-aarcange@redhat.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Michael Rapoport <RAPOPORT@il.ibm.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
hugetlb_mcopy_atomic_pte is the low level routine that implements the
userfaultfd UFFDIO_COPY command. It is based on the existing
mcopy_atomic_pte routine with modifications for huge pages.
Link: http://lkml.kernel.org/r/20161216144821.5183-18-aarcange@redhat.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Michael Rapoport <RAPOPORT@il.ibm.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
return_unused_surplus_pages() decrements the global reservation count,
and frees any unused surplus pages that were backing the reservation.
Commit 7848a4bf51 ("mm/hugetlb.c: add cond_resched_lock() in
return_unused_surplus_pages()") added a call to cond_resched_lock in the
loop freeing the pages.
As a result, the hugetlb_lock could be dropped, and someone else could
use the pages that will be freed in subsequent iterations of the loop.
This could result in inconsistent global hugetlb page state, application
api failures (such as mmap) failures or application crashes.
When dropping the lock in return_unused_surplus_pages, make sure that
the global reservation count (resv_huge_pages) remains sufficiently
large to prevent someone else from claiming pages about to be freed.
Analyzed by Paul Cassella.
Fixes: 7848a4bf51 ("mm/hugetlb.c: add cond_resched_lock() in return_unused_surplus_pages()")
Link: http://lkml.kernel.org/r/1483991767-6879-1-git-send-email-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reported-by: Paul Cassella <cassella@cray.com>
Suggested-by: Michal Hocko <mhocko@kernel.org>
Cc: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: <stable@vger.kernel.org> [3.15+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With commit e77b0852b5 ("mm/mmu_gather: track page size with mmu
gather and force flush if page size change") we added the ability to
force a tlb flush when the page size change in a mmu_gather loop. We
did that by checking for a page size change every time we added a page
to mmu_gather for lazy flush/remove. We can improve that by moving the
page size change check early and not doing it every time we add a page.
This also helps us to do tlb flush when invalidating a range covering
dax mapping. Wrt dax mapping we don't have a backing struct page and
hence we don't call tlb_remove_page, which earlier forced the tlb flush
on page size change. Moving the page size change check earlier means we
will do the same even for dax mapping.
We also avoid doing this check on architecture other than powerpc.
In a later patch we will remove page size check from tlb_remove_page().
Link: http://lkml.kernel.org/r/20161026084839.27299-5-aneesh.kumar@linux.vnet.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This add tlb_remove_hugetlb_entry similar to tlb_remove_pmd_tlb_entry.
Link: http://lkml.kernel.org/r/20161026084839.27299-4-aneesh.kumar@linux.vnet.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We cannot use the pte value used in set_pte_at for pte_same comparison,
because archs like ppc64, filter/add new pte flag in set_pte_at.
Instead fetch the pte value inside hugetlb_cow. We are comparing pte
value to make sure the pte didn't change since we dropped the page table
lock. hugetlb_cow get called with page table lock held, and we can take
a copy of the pte value before we drop the page table lock.
With hugetlbfs, we optimize the MAP_PRIVATE write fault path with no
previous mapping (huge_pte_none entries), by forcing a cow in the fault
path. This avoid take an addition fault to covert a read-only mapping
to read/write. Here we were comparing a recently instantiated pte (via
set_pte_at) to the pte values from linux page table. As explained above
on ppc64 such pte_same check returned wrong result, resulting in us
taking an additional fault on ppc64.
Fixes: 6a119eae94 ("powerpc/mm: Add a _PAGE_PTE bit")
Link: http://lkml.kernel.org/r/20161018154245.18023-1-aneesh.kumar@linux.vnet.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Reported-by: Jan Stancek <jstancek@redhat.com>
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Scott Wood <scottwood@freescale.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Error paths in hugetlb_cow() and hugetlb_no_page() may free a newly
allocated huge page.
If a reservation was associated with the huge page, alloc_huge_page()
consumed the reservation while allocating. When the newly allocated
page is freed in free_huge_page(), it will increment the global
reservation count. However, the reservation entry in the reserve map
will remain.
This is not an issue for shared mappings as the entry in the reserve map
indicates a reservation exists. But, an entry in a private mapping
reserve map indicates the reservation was consumed and no longer exists.
This results in an inconsistency between the reserve map and the global
reservation count. This 'leaks' a reserved huge page.
Create a new routine restore_reserve_on_error() to restore the reserve
entry in these specific error paths. This routine makes use of a new
function vma_add_reservation() which will add a reserve entry for a
specific address/page.
In general, these error paths were rarely (if ever) taken on most
architectures. However, powerpc contained arch specific code that that
resulted in an extra fault and execution of these error paths on all
private mappings.
Fixes: 67961f9db8 ("mm/hugetlb: fix huge page reserve accounting for private mappings)
Link: http://lkml.kernel.org/r/1476933077-23091-2-git-send-email-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reported-by: Jan Stancek <jstancek@redhat.com>
Tested-by: Jan Stancek <jstancek@redhat.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Kirill A . Shutemov <kirill.shutemov@linux.intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 <zhongjiang@huawei.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Tested-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Avoid making ifdef get pretty unwieldy if many ARCHs support gigantic
page. No functional change with this patch.
Link: http://lkml.kernel.org/r/1475227569-63446-2-git-send-email-xieyisheng1@huawei.com
Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com>
Suggested-by: Michal Hocko <mhocko@suse.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For every pfn aligned to minimum_order, dissolve_free_huge_pages() will
call dissolve_free_huge_page() which takes the hugetlb spinlock, even if
the page is not huge at all or a hugepage that is in-use.
Improve this by doing the PageHuge() and page_count() checks already in
dissolve_free_huge_pages() before calling dissolve_free_huge_page(). In
dissolve_free_huge_page(), when holding the spinlock, those checks need
to be revalidated.
Link: http://lkml.kernel.org/r/20160926172811.94033-4-gerald.schaefer@de.ibm.com
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Rui Teng <rui.teng@linux.vnet.ibm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 <gerald.schaefer@de.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Rui Teng <rui.teng@linux.vnet.ibm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "mm/hugetlb: memory offline issues with hugepages", v4.
This addresses several issues with hugepages and memory offline. While
the first patch fixes a panic, and is therefore rather important, the
last patch is just a performance optimization.
The second patch fixes a theoretical issue with reserved hugepages,
while still leaving some ugly usability issue, see description.
This patch (of 3):
dissolve_free_huge_pages() will either run into the VM_BUG_ON() or a
list corruption and addressing exception when trying to set a memory
block offline that is part (but not the first part) of a "gigantic"
hugetlb page with a size > memory block size.
When no other smaller hugetlb page sizes are present, the VM_BUG_ON()
will trigger directly. In the other case we will run into an addressing
exception later, because dissolve_free_huge_page() will not work on the
head page of the compound hugetlb page which will result in a NULL
hstate from page_hstate().
To fix this, first remove the VM_BUG_ON() because it is wrong, and then
use the compound head page in dissolve_free_huge_page(). This means
that an unused pre-allocated gigantic page that has any part of itself
inside the memory block that is going offline will be dissolved
completely. Losing an unused gigantic hugepage is preferable to failing
the memory offline, for example in the situation where a (possibly
faulty) memory DIMM needs to go offline.
Fixes: c8721bbb ("mm: memory-hotplug: enable memory hotplug to handle hugepage")
Link: http://lkml.kernel.org/r/20160926172811.94033-2-gerald.schaefer@de.ibm.com
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Rui Teng <rui.teng@linux.vnet.ibm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When memory hotplug operates, free hugepages will be freed if the
movable node is offline. Therefore, /proc/sys/vm/nr_hugepages will be
incorrect.
Fix it by reducing max_huge_pages when the node is offlined.
n-horiguchi@ah.jp.nec.com said:
: dissolve_free_huge_page intends to break a hugepage into buddy, and the
: destination hugepage is supposed to be allocated from the pool of the
: destination node, so the system-wide pool size is reduced. So adding
: h->max_huge_pages-- makes sense to me.
Link: http://lkml.kernel.org/r/1470624546-902-1-git-send-email-zhongjiang@huawei.com
Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fixes:
- Fix early access to cpu_spec relocation from Benjamin Herrenschmidt
- Fix incorrect event codes in power9-event-list from Madhavan Srinivasan
- Move register_process_table() out of ppc_md from Michael Ellerman
Use jump_label for [cpu|mmu]_has_feature() from Aneesh Kumar K.V, Kevin Hao and Michael Ellerman:
- Add mmu_early_init_devtree() from Michael Ellerman
- Move disable_radix handling into mmu_early_init_devtree() from Michael Ellerman
- Do hash device tree scanning earlier from Michael Ellerman
- Do radix device tree scanning earlier from Michael Ellerman
- Do feature patching before MMU init from Michael Ellerman
- Check features don't change after patching from Michael Ellerman
- Make MMU_FTR_RADIX a MMU family feature from Aneesh Kumar K.V
- Convert mmu_has_feature() to returning bool from Michael Ellerman
- Convert cpu_has_feature() to returning bool from Michael Ellerman
- Define radix_enabled() in one place & use static inline from Michael Ellerman
- Add early_[cpu|mmu]_has_feature() from Michael Ellerman
- Convert early cpu/mmu feature check to use the new helpers from Aneesh Kumar K.V
- jump_label: Make it possible for arches to invoke jump_label_init() earlier from Kevin Hao
- Call jump_label_init() in apply_feature_fixups() from Aneesh Kumar K.V
- Remove mfvtb() from Kevin Hao
- Move cpu_has_feature() to a separate file from Kevin Hao
- Add kconfig option to use jump labels for cpu/mmu_has_feature() from Michael Ellerman
- Add option to use jump label for cpu_has_feature() from Kevin Hao
- Add option to use jump label for mmu_has_feature() from Kevin Hao
- Catch usage of cpu/mmu_has_feature() before jump label init from Aneesh Kumar K.V
- Annotate jump label assembly from Michael Ellerman
TLB flush enhancements from Aneesh Kumar K.V:
- radix: Implement tlb mmu gather flush efficiently
- Add helper for finding SLBE LLP encoding
- Use hugetlb flush functions
- Drop multiple definition of mm_is_core_local
- radix: Add tlb flush of THP ptes
- radix: Rename function and drop unused arg
- radix/hugetlb: Add helper for finding page size
- hugetlb: Add flush_hugetlb_tlb_range
- remove flush_tlb_page_nohash
Add new ptrace regsets from Anshuman Khandual and Simon Guo:
- elf: Add powerpc specific core note sections
- Add the function flush_tmregs_to_thread
- Enable in transaction NT_PRFPREG ptrace requests
- Enable in transaction NT_PPC_VMX ptrace requests
- Enable in transaction NT_PPC_VSX ptrace requests
- Adapt gpr32_get, gpr32_set functions for transaction
- Enable support for NT_PPC_CGPR
- Enable support for NT_PPC_CFPR
- Enable support for NT_PPC_CVMX
- Enable support for NT_PPC_CVSX
- Enable support for TM SPR state
- Enable NT_PPC_TM_CTAR, NT_PPC_TM_CPPR, NT_PPC_TM_CDSCR
- Enable support for NT_PPPC_TAR, NT_PPC_PPR, NT_PPC_DSCR
- Enable support for EBB registers
- Enable support for Performance Monitor registers
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Merge tag 'powerpc-4.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull more powerpc updates from Michael Ellerman:
"These were delayed for various reasons, so I let them sit in next a
bit longer, rather than including them in my first pull request.
Fixes:
- Fix early access to cpu_spec relocation from Benjamin Herrenschmidt
- Fix incorrect event codes in power9-event-list from Madhavan Srinivasan
- Move register_process_table() out of ppc_md from Michael Ellerman
Use jump_label use for [cpu|mmu]_has_feature():
- Add mmu_early_init_devtree() from Michael Ellerman
- Move disable_radix handling into mmu_early_init_devtree() from Michael Ellerman
- Do hash device tree scanning earlier from Michael Ellerman
- Do radix device tree scanning earlier from Michael Ellerman
- Do feature patching before MMU init from Michael Ellerman
- Check features don't change after patching from Michael Ellerman
- Make MMU_FTR_RADIX a MMU family feature from Aneesh Kumar K.V
- Convert mmu_has_feature() to returning bool from Michael Ellerman
- Convert cpu_has_feature() to returning bool from Michael Ellerman
- Define radix_enabled() in one place & use static inline from Michael Ellerman
- Add early_[cpu|mmu]_has_feature() from Michael Ellerman
- Convert early cpu/mmu feature check to use the new helpers from Aneesh Kumar K.V
- jump_label: Make it possible for arches to invoke jump_label_init() earlier from Kevin Hao
- Call jump_label_init() in apply_feature_fixups() from Aneesh Kumar K.V
- Remove mfvtb() from Kevin Hao
- Move cpu_has_feature() to a separate file from Kevin Hao
- Add kconfig option to use jump labels for cpu/mmu_has_feature() from Michael Ellerman
- Add option to use jump label for cpu_has_feature() from Kevin Hao
- Add option to use jump label for mmu_has_feature() from Kevin Hao
- Catch usage of cpu/mmu_has_feature() before jump label init from Aneesh Kumar K.V
- Annotate jump label assembly from Michael Ellerman
TLB flush enhancements from Aneesh Kumar K.V:
- radix: Implement tlb mmu gather flush efficiently
- Add helper for finding SLBE LLP encoding
- Use hugetlb flush functions
- Drop multiple definition of mm_is_core_local
- radix: Add tlb flush of THP ptes
- radix: Rename function and drop unused arg
- radix/hugetlb: Add helper for finding page size
- hugetlb: Add flush_hugetlb_tlb_range
- remove flush_tlb_page_nohash
Add new ptrace regsets from Anshuman Khandual and Simon Guo:
- elf: Add powerpc specific core note sections
- Add the function flush_tmregs_to_thread
- Enable in transaction NT_PRFPREG ptrace requests
- Enable in transaction NT_PPC_VMX ptrace requests
- Enable in transaction NT_PPC_VSX ptrace requests
- Adapt gpr32_get, gpr32_set functions for transaction
- Enable support for NT_PPC_CGPR
- Enable support for NT_PPC_CFPR
- Enable support for NT_PPC_CVMX
- Enable support for NT_PPC_CVSX
- Enable support for TM SPR state
- Enable NT_PPC_TM_CTAR, NT_PPC_TM_CPPR, NT_PPC_TM_CDSCR
- Enable support for NT_PPPC_TAR, NT_PPC_PPR, NT_PPC_DSCR
- Enable support for EBB registers
- Enable support for Performance Monitor registers"
* tag 'powerpc-4.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (48 commits)
powerpc/mm: Move register_process_table() out of ppc_md
powerpc/perf: Fix incorrect event codes in power9-event-list
powerpc/32: Fix early access to cpu_spec relocation
powerpc/ptrace: Enable support for Performance Monitor registers
powerpc/ptrace: Enable support for EBB registers
powerpc/ptrace: Enable support for NT_PPPC_TAR, NT_PPC_PPR, NT_PPC_DSCR
powerpc/ptrace: Enable NT_PPC_TM_CTAR, NT_PPC_TM_CPPR, NT_PPC_TM_CDSCR
powerpc/ptrace: Enable support for TM SPR state
powerpc/ptrace: Enable support for NT_PPC_CVSX
powerpc/ptrace: Enable support for NT_PPC_CVMX
powerpc/ptrace: Enable support for NT_PPC_CFPR
powerpc/ptrace: Enable support for NT_PPC_CGPR
powerpc/ptrace: Adapt gpr32_get, gpr32_set functions for transaction
powerpc/ptrace: Enable in transaction NT_PPC_VSX ptrace requests
powerpc/ptrace: Enable in transaction NT_PPC_VMX ptrace requests
powerpc/ptrace: Enable in transaction NT_PRFPREG ptrace requests
powerpc/process: Add the function flush_tmregs_to_thread
elf: Add powerpc specific core note sections
powerpc/mm: remove flush_tlb_page_nohash
powerpc/mm/hugetlb: Add flush_hugetlb_tlb_range
...
Zhong Jiang has reported a BUG_ON from huge_pte_alloc hitting when he
runs his database load with memory online and offline running in
parallel. The reason is that huge_pmd_share might detect a shared pmd
which is currently migrated and so it has migration pte which is
!pte_huge.
There doesn't seem to be any easy way to prevent from the race and in
fact seeing the migration swap entry is not harmful. Both callers of
huge_pte_alloc are prepared to handle them. copy_hugetlb_page_range
will copy the swap entry and make it COW if needed. hugetlb_fault will
back off and so the page fault is retries if the page is still under
migration and waits for its completion in hugetlb_fault.
That means that the BUG_ON is wrong and we should update it. Let's
simply check that all present ptes are pte_huge instead.
Link: http://lkml.kernel.org/r/20160721074340.GA26398@dhcp22.suse.cz
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: zhongjiang <zhongjiang@huawei.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In powerpc servers with large memory(32TB), we watched several soft
lockups for hugepage under stress tests.
The call traces are as follows:
1.
get_page_from_freelist+0x2d8/0xd50
__alloc_pages_nodemask+0x180/0xc20
alloc_fresh_huge_page+0xb0/0x190
set_max_huge_pages+0x164/0x3b0
2.
prep_new_huge_page+0x5c/0x100
alloc_fresh_huge_page+0xc8/0x190
set_max_huge_pages+0x164/0x3b0
This patch fixes such soft lockups. It is safe to call cond_resched()
there because it is out of spin_lock/unlock section.
Link: http://lkml.kernel.org/r/1469674442-14848-1-git-send-email-hejianet@gmail.com
Signed-off-by: Jia He <hejianet@gmail.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some archs like ppc64 need to do special things when flushing tlb for
hugepage. Add a new helper to flush hugetlb tlb range. This helps us to
avoid flushing the entire tlb mapping for the pid.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Merge more updates from Andrew Morton:
"The rest of MM"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (101 commits)
mm, compaction: simplify contended compaction handling
mm, compaction: introduce direct compaction priority
mm, thp: remove __GFP_NORETRY from khugepaged and madvised allocations
mm, page_alloc: make THP-specific decisions more generic
mm, page_alloc: restructure direct compaction handling in slowpath
mm, page_alloc: don't retry initial attempt in slowpath
mm, page_alloc: set alloc_flags only once in slowpath
lib/stackdepot.c: use __GFP_NOWARN for stack allocations
mm, kasan: switch SLUB to stackdepot, enable memory quarantine for SLUB
mm, kasan: account for object redzone in SLUB's nearest_obj()
mm: fix use-after-free if memory allocation failed in vma_adjust()
zsmalloc: Delete an unnecessary check before the function call "iput"
mm/memblock.c: fix index adjustment error in __next_mem_range_rev()
mem-hotplug: alloc new page from a nearest neighbor node when mem-offline
mm: optimize copy_page_to/from_iter_iovec
mm: add cond_resched() to generic_swapfile_activate()
Revert "mm, mempool: only set __GFP_NOMEMALLOC if there are free elements"
mm, compaction: don't isolate PageWriteback pages in MIGRATE_SYNC_LIGHT mode
mm: hwpoison: remove incorrect comments
make __section_nr() more efficient
...
dequeue_hwpoisoned_huge_page() can be called without page lock hold, so
let's remove incorrect comment.
The reason why the page lock is not really needed is that
dequeue_hwpoisoned_huge_page() checks page_huge_active() inside
hugetlb_lock, which allows us to avoid trying to dequeue a hugepage that
are just allocated but not linked to active list yet, even without
taking page lock.
Link: http://lkml.kernel.org/r/20160720092901.GA15995@www9186uo.sakura.ne.jp
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reported-by: Zhan Chen <zhanc1@andrew.cmu.edu>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull vfs updates from Al Viro:
"Assorted cleanups and fixes.
Probably the most interesting part long-term is ->d_init() - that will
have a bunch of followups in (at least) ceph and lustre, but we'll
need to sort the barrier-related rules before it can get used for
really non-trivial stuff.
Another fun thing is the merge of ->d_iput() callers (dentry_iput()
and dentry_unlink_inode()) and a bunch of ->d_compare() ones (all
except the one in __d_lookup_lru())"
* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (26 commits)
fs/dcache.c: avoid soft-lockup in dput()
vfs: new d_init method
vfs: Update lookup_dcache() comment
bdev: get rid of ->bd_inodes
Remove last traces of ->sync_page
new helper: d_same_name()
dentry_cmp(): use lockless_dereference() instead of smp_read_barrier_depends()
vfs: clean up documentation
vfs: document ->d_real()
vfs: merge .d_select_inode() into .d_real()
unify dentry_iput() and dentry_unlink_inode()
binfmt_misc: ->s_root is not going anywhere
drop redundant ->owner initializations
ufs: get rid of redundant checks
orangefs: constify inode_operations
missed comment updates from ->direct_IO() prototype change
file_inode(f)->i_mapping is f->f_mapping
trim fsnotify hooks a bit
9p: new helper - v9fs_parent_fid()
debugfs: ->d_parent is never NULL or negative
...
Merge updates from Andrew Morton:
- a few misc bits
- ocfs2
- most(?) of MM
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (125 commits)
thp: fix comments of __pmd_trans_huge_lock()
cgroup: remove unnecessary 0 check from css_from_id()
cgroup: fix idr leak for the first cgroup root
mm: memcontrol: fix documentation for compound parameter
mm: memcontrol: remove BUG_ON in uncharge_list
mm: fix build warnings in <linux/compaction.h>
mm, thp: convert from optimistic swapin collapsing to conservative
mm, thp: fix comment inconsistency for swapin readahead functions
thp: update Documentation/{vm/transhuge,filesystems/proc}.txt
shmem: split huge pages beyond i_size under memory pressure
thp: introduce CONFIG_TRANSPARENT_HUGE_PAGECACHE
khugepaged: add support of collapse for tmpfs/shmem pages
shmem: make shmem_inode_info::lock irq-safe
khugepaged: move up_read(mmap_sem) out of khugepaged_alloc_page()
thp: extract khugepaged from mm/huge_memory.c
shmem, thp: respect MADV_{NO,}HUGEPAGE for file mappings
shmem: add huge pages support
shmem: get_unmapped_area align huge page
shmem: prepare huge= mount option and sysfs knob
mm, rmap: account shmem thp pages
...
This allows an arch which needs to do special handing with respect to
different page size when flushing tlb to implement the same in mmu
gather.
Link: http://lkml.kernel.org/r/1465049193-22197-3-git-send-email-aneesh.kumar@linux.vnet.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Hugh Dickins <hughd@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For hugetlb like THP (and unlike regular page), we do tlb flush after
dropping ptl. Because of the above, we don't need to track force_flush
like we do now. Instead we can simply call tlb_remove_page() which will
do the flush if needed.
No functionality change in this patch.
Link: http://lkml.kernel.org/r/1465049193-22197-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull s390 updates from Martin Schwidefsky:
"There are a couple of new things for s390 with this merge request:
- a new scheduling domain "drawer" is added to reflect the unusual
topology found on z13 machines. Performance tests showed up to 8
percent gain with the additional domain.
- the new crc-32 checksum crypto module uses the vector-galois-field
multiply and sum SIMD instruction to speed up crc-32 and crc-32c.
- proper __ro_after_init support, this requires RO_AFTER_INIT_DATA in
the generic vmlinux.lds linker script definitions.
- kcov instrumentation support. A prerequisite for that is the
inline assembly basic block cleanup, which is the reason for the
net/iucv/iucv.c change.
- support for 2GB pages is added to the hugetlbfs backend.
Then there are two removals:
- the oprofile hardware sampling support is dead code and is removed.
The oprofile user space uses the perf interface nowadays.
- the ETR clock synchronization is removed, this has been superseeded
be the STP clock synchronization. And it always has been
"interesting" code..
And the usual bug fixes and cleanups"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (82 commits)
s390/pci: Delete an unnecessary check before the function call "pci_dev_put"
s390/smp: clean up a condition
s390/cio/chp : Remove deprecated create_singlethread_workqueue
s390/chsc: improve channel path descriptor determination
s390/chsc: sanitize fmt check for chp_desc determination
s390/cio: make fmt1 channel path descriptor optional
s390/chsc: fix ioctl CHSC_INFO_CU command
s390/cio/device_ops: fix kernel doc
s390/cio: allow to reset channel measurement block
s390/console: Make preferred console handling more consistent
s390/mm: fix gmap tlb flush issues
s390/mm: add support for 2GB hugepages
s390: have unique symbol for __switch_to address
s390/cpuinfo: show maximum thread id
s390/ptrace: clarify bits in the per_struct
s390: stack address vs thread_info
s390: remove pointless load within __switch_to
s390: enable kcov support
s390/cpumf: use basic block for ecctr inline assembly
s390/hypfs: use basic block for diag inline assembly
...
The VM_BUG_ON_PAGE in page_move_anon_rmap() is more trouble than it's
worth: the syzkaller fuzzer hit it again. It's still wrong for some THP
cases, because linear_page_index() was never intended to apply to
addresses before the start of a vma.
That's easily fixed with a signed long cast inside linear_page_index();
and Dmitry has tested such a patch, to verify the false positive. But
why extend linear_page_index() just for this case? when the avoidance in
page_move_anon_rmap() has already grown ugly, and there's no reason for
the check at all (nothing else there is using address or index).
Remove address arg from page_move_anon_rmap(), remove VM_BUG_ON_PAGE,
remove CONFIG_DEBUG_VM PageTransHuge adjustment.
And one more thing: should the compound_head(page) be done inside or
outside page_move_anon_rmap()? It's usually pushed down to the lowest
level nowadays (and mm/memory.c shows no other explicit use of it), so I
think it's better done in page_move_anon_rmap() than by caller.
Fixes: 0798d3c022 ("mm: thp: avoid false positive VM_BUG_ON_PAGE in page_move_anon_rmap()")
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.1607120444540.12528@eggly.anvils
Signed-off-by: Hugh Dickins <hughd@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: <stable@vger.kernel.org> [4.5+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This adds support for 2GB hugetlbfs pages on s390.
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
While working on s390 support for gigantic hugepages I ran into the
following "Bad page state" warning when freeing gigantic pages:
BUG: Bad page state in process bash pfn:580001
page:000003d116000040 count:0 mapcount:0 mapping:ffffffff00000000 index:0x0
flags: 0x7fffc0000000000()
page dumped because: non-NULL mapping
This is because page->compound_mapcount, which is part of a union with
page->mapping, is initialized with -1 in prep_compound_gigantic_page(),
and not cleared again during destroy_compound_gigantic_page(). Fix this
by clearing the compound_mapcount in destroy_compound_gigantic_page()
before clearing compound_head.
Interestingly enough, the warning will not show up on x86_64, although
this should not be architecture specific. Apparently there is an
endianness issue, combined with the fact that the union contains both a
64 bit ->mapping pointer and a 32 bit atomic_t ->compound_mapcount as
members. The resulting bogus page->mapping on x86_64 therefore contains
00000000ffffffff instead of ffffffff00000000 on s390, which will falsely
trigger the PageAnon() check in free_pages_prepare() because
page->mapping & PAGE_MAPPING_ANON is true on little-endian architectures
like x86_64 in this case (the page is not compound anymore,
->compound_head was already cleared before). As a result, page->mapping
will be cleared before doing the checks in free_pages_check().
Not sure if the bogus "PageAnon() returning true" on x86_64 for the
first tail page of a gigantic page (at this stage) has other theoretical
implications, but they would also be fixed with this patch.
Link: http://lkml.kernel.org/r/1466612719-5642-1-git-send-email-gerald.schaefer@de.ibm.com
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We account HugeTLB's shared page table to all processes who share it.
The accounting happens during huge_pmd_share().
If somebody populates pud entry under us, we should decrease pagetable's
refcount and decrease nr_pmds of the process.
By mistake, I increase nr_pmds again in this case. :-/ It will lead to
"BUG: non-zero nr_pmds on freeing mm: 2" on process' exit.
Let's fix this by increasing nr_pmds only when we're sure that the page
table will be used.
Link: http://lkml.kernel.org/r/20160617122506.GC6534@node.shutemov.name
Fixes: dc6c9a35b6 ("mm: account pmd page tables to the process")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: zhongjiang <zhongjiang@huawei.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When creating a private mapping of a hugetlbfs file, it is possible to
unmap pages via ftruncate or fallocate hole punch. If subsequent faults
repopulate these mappings, the reserve counts will go negative. This is
because the code currently assumes all faults to private mappings will
consume reserves. The problem can be recreated as follows:
- mmap(MAP_PRIVATE) a file in hugetlbfs filesystem
- write fault in pages in the mapping
- fallocate(FALLOC_FL_PUNCH_HOLE) some pages in the mapping
- write fault in pages in the hole
This will result in negative huge page reserve counts and negative
subpool usage counts for the hugetlbfs. Note that this can also be
recreated with ftruncate, but fallocate is more straight forward.
This patch modifies the routines vma_needs_reserves and vma_has_reserves
to examine the reserve map associated with private mappings similar to
that for shared mappings. However, the reserve map semantics for
private and shared mappings are very different. This results in subtly
different code that is explained in the comments.
Link: http://lkml.kernel.org/r/1464720957-15698-1-git-send-email-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1/ Device DAX for persistent memory:
Device DAX is the device-centric analogue of Filesystem DAX
(CONFIG_FS_DAX). It allows memory ranges to be allocated and mapped
without need of an intervening file system. Device DAX is strict,
precise and predictable. Specifically this interface:
a) Guarantees fault granularity with respect to a given page size
(pte, pmd, or pud) set at configuration time.
b) Enforces deterministic behavior by being strict about what fault
scenarios are supported.
Persistent memory is the first target, but the mechanism is also
targeted for exclusive allocations of performance/feature differentiated
memory ranges.
2/ Support for the HPE DSM (device specific method) command formats.
This enables management of these first generation devices until a
unified DSM specification materializes.
3/ Further ACPI 6.1 compliance with support for the common dimm
identifier format.
4/ Various fixes and cleanups across the subsystem.
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Merge tag 'libnvdimm-for-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updates from Dan Williams:
"The bulk of this update was stabilized before the merge window and
appeared in -next. The "device dax" implementation was revised this
week in response to review feedback, and to address failures detected
by the recently expanded ndctl unit test suite.
Not included in this pull request are two dax topic branches (dax
error handling, and dax radix-tree locking). These topics were
deferred to get a few more days of -next integration testing, and to
coordinate a branch baseline with Ted and the ext4 tree. Vishal and
Ross will send the error handling and locking topics respectively in
the next few days.
This branch has received a positive build result from the kbuild robot
across 226 configs.
Summary:
- Device DAX for persistent memory: Device DAX is the device-centric
analogue of Filesystem DAX (CONFIG_FS_DAX). It allows memory
ranges to be allocated and mapped without need of an intervening
file system. Device DAX is strict, precise and predictable.
Specifically this interface:
a) Guarantees fault granularity with respect to a given page size
(pte, pmd, or pud) set at configuration time.
b) Enforces deterministic behavior by being strict about what
fault scenarios are supported.
Persistent memory is the first target, but the mechanism is also
targeted for exclusive allocations of performance/feature
differentiated memory ranges.
- Support for the HPE DSM (device specific method) command formats.
This enables management of these first generation devices until a
unified DSM specification materializes.
- Further ACPI 6.1 compliance with support for the common dimm
identifier format.
- Various fixes and cleanups across the subsystem"
* tag 'libnvdimm-for-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (40 commits)
libnvdimm, dax: fix deletion
libnvdimm, dax: fix alignment validation
libnvdimm, dax: autodetect support
libnvdimm: release ida resources
Revert "block: enable dax for raw block devices"
/dev/dax, core: file operations and dax-mmap
/dev/dax, pmem: direct access to persistent memory
libnvdimm: stop requiring a driver ->remove() method
libnvdimm, dax: record the specified alignment of a dax-device instance
libnvdimm, dax: reserve space to store labels for device-dax
libnvdimm, dax: introduce device-dax infrastructure
nfit: add sysfs dimm 'family' and 'dsm_mask' attributes
tools/testing/nvdimm: ND_CMD_CALL support
nfit: disable vendor specific commands
nfit: export subsystem ids as attributes
nfit: fix format interface code byte order per ACPI6.1
nfit, libnvdimm: limited/whitelisted dimm command marshaling mechanism
nfit, libnvdimm: clarify "commands" vs "_DSMs"
libnvdimm: increase max envelope size for ioctl
acpi/nfit: Add sysfs "id" for NVDIMM ID
...
The "Device DAX" core enables dax mappings of performance / feature
differentiated memory. An open mapping or file handle keeps the backing
struct device live, but new mappings are only possible while the device
is enabled. Faults are handled under rcu_read_lock to synchronize
with the enabled state of the device.
Similar to the filesystem-dax case the backing memory may optionally
have struct page entries. However, unlike fs-dax there is no support
for private mappings, or mappings that are not backed by media (see
use of zero-page in fs-dax).
Mappings are always guaranteed to match the alignment of the dax_region.
If the dax_region is configured to have a 2MB alignment, all mappings
are guaranteed to be backed by a pmd entry. Contrast this determinism
with the fs-dax case where pmd mappings are opportunistic. If userspace
attempts to force a misaligned mapping, the driver will fail the mmap
attempt. See dax_dev_check_vma() for other scenarios that are rejected,
like MAP_PRIVATE mappings.
Cc: Hannes Reinecke <hare@suse.de>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This patchset deals with some problematic sites that iterate pfn ranges.
There is a system thats node's pfns are overlapped as follows:
-----pfn-------->
N0 N1 N2 N0 N1 N2
Therefore, we need to take care of this overlapping when iterating pfn
range.
I audit many iterating sites that uses pfn_valid(), pfn_valid_within(),
zone_start_pfn and etc. and others looks safe to me. This is a
preparation step for a new CMA implementation, ZONE_CMA
(https://lkml.org/lkml/2015/2/12/95), because it would be easily
overlapped with other zones. But, zone overlap check is also needed for
the general case so I send it separately.
This patch (of 5):
alloc_gigantic_page() uses alloc_contig_range() and this requires that
the requested range is in a single zone. To satisfy this requirement,
add this check to pfn_range_valid_gigantic().
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 <vaishali.thakkar@oracle.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
Cc: Dominik Dingel <dingel@linux.vnet.ibm.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It was observed that minimum size accounting associated with the
hugetlbfs min_size mount option may not perform optimally and as
expected. As huge pages/reservations are released from the filesystem
and given back to the global pools, they are reserved for subsequent
filesystem use as long as the subpool reserved count is less than
subpool minimum size. It does not take into account used pages within
the filesystem. The filesystem size limits are not exceeded and this is
technically not a bug. However, better behavior would be to wait for
the number of used pages/reservations associated with the filesystem to
drop below the minimum size before taking reservations to satisfy
minimum size.
An optimization is also made to the hugepage_subpool_get_pages() routine
which is called when pages/reservations are allocated. This does not
change behavior, but simply avoids the accounting if all reservations
have already been taken (subpool reserved count == 0).
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Lots of code does
node = next_node(node, XXX);
if (node == MAX_NUMNODES)
node = first_node(XXX);
so create next_node_in() to do this and use it in various places.
[mhocko@suse.com: use next_node_in() helper]
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Hui Zhu <zhuhui@xiaomi.com>
Cc: Wang Xiaoqiang <wangxq10@lzu.edu.cn>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.
This promise never materialized. And unlikely will.
We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE. And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.
Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.
Let's stop pretending that pages in page cache are special. They are
not.
The changes are pretty straight-forward:
- <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
- <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
- PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};
- page_cache_get() -> get_page();
- page_cache_release() -> put_page();
This patch contains automated changes generated with coccinelle using
script below. For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.
The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.
There are few places in the code where coccinelle didn't reach. I'll
fix them manually in a separate patch. Comments and documentation also
will be addressed with the separate patch.
virtual patch
@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E
@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E
@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT
@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE
@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK
@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)
@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)
@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There are a mixture of pr_warning and pr_warn uses in mm. Use pr_warn
consistently.
Miscellanea:
- Coalesce formats
- Realign arguments
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Tejun Heo <tj@kernel.org> [percpu]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace ENOTSUPP with EOPNOTSUPP. If hugepages are not supported, this
value is propagated to userspace. EOPNOTSUPP is part of uapi and is
widely supported by libc libraries.
It gives nicer message to user, rather than:
# cat /proc/sys/vm/nr_hugepages
cat: /proc/sys/vm/nr_hugepages: Unknown error 524
And also LTP's proc01 test was failing because this ret code (524)
was unexpected:
proc01 1 TFAIL : proc01.c:396: read failed: /proc/sys/vm/nr_hugepages: errno=???(524): Unknown error 524
proc01 2 TFAIL : proc01.c:396: read failed: /proc/sys/vm/nr_hugepages_mempolicy: errno=???(524): Unknown error 524
proc01 3 TFAIL : proc01.c:396: read failed: /proc/sys/vm/nr_overcommit_hugepages: errno=???(524): Unknown error 524
Signed-off-by: Jan Stancek <jstancek@redhat.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The warning message "killed due to inadequate hugepage pool" simply
indicates that SIGBUS was sent, not that the process was forcibly killed.
If the process has a signal handler installed does not fix the problem,
this message can rapidly spam the kernel log.
On my amd64 dev machine that does not have hugepages configured, I can
reproduce the repeated warnings easily by setting vm.nr_hugepages=2 (i.e.,
4 megabytes of huge pages) and running something that sets a signal
handler and forks, like
#include <sys/mman.h>
#include <signal.h>
#include <stdlib.h>
#include <unistd.h>
sig_atomic_t counter = 10;
void handler(int signal)
{
if (counter-- == 0)
exit(0);
}
int main(void)
{
int status;
char *addr = mmap(NULL, 4 * 1048576, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB, -1, 0);
if (addr == MAP_FAILED) {perror("mmap"); return 1;}
*addr = 'x';
switch (fork()) {
case -1:
perror("fork"); return 1;
case 0:
signal(SIGBUS, handler);
*addr = 'x';
break;
default:
*addr = 'x';
wait(&status);
if (WIFSIGNALED(status)) {
psignal(WTERMSIG(status), "child");
}
break;
}
}
Signed-off-by: Geoffrey Thomas <geofft@ldpreload.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently incorrect default hugepage pool size is reported by proc
nr_hugepages when number of pages for the default huge page size is
specified twice.
When multiple huge page sizes are supported, /proc/sys/vm/nr_hugepages
indicates the current number of pre-allocated huge pages of the default
size. Basically /proc/sys/vm/nr_hugepages displays default_hstate->
max_huge_pages and after boot time pre-allocation, max_huge_pages should
equal the number of pre-allocated pages (nr_hugepages).
Test case:
Note that this is specific to x86 architecture.
Boot the kernel with command line option 'default_hugepagesz=1G
hugepages=X hugepagesz=2M hugepages=Y hugepagesz=1G hugepages=Z'. After
boot, 'cat /proc/sys/vm/nr_hugepages' and 'sysctl -a | grep hugepages'
returns the value X. However, dmesg output shows that Z huge pages were
pre-allocated.
So, the root cause of the problem here is that the global variable
default_hstate_max_huge_pages is set if a default huge page size is
specified (directly or indirectly) on the command line. After the command
line processing in hugetlb_init, if default_hstate_max_huge_pages is set,
the value is assigned to default_hstae.max_huge_pages. However,
default_hstate.max_huge_pages may have already been set based on the
number of pre-allocated huge pages of default_hstate size.
The solution to this problem is if hstate->max_huge_pages is already set
then it should not set as a result of global max_huge_pages value.
Basically if the value of the variable hugepages is set multiple times on
a command line for a specific supported hugepagesize then proc layer
should consider the last specified value.
Signed-off-by: Vaishali Thakkar <vaishali.thakkar@oracle.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 944d9fec8d ("hugetlb: add support for gigantic page allocation
at runtime") has added the runtime gigantic page allocation via
alloc_contig_range(), making this support available only when CONFIG_CMA
is enabled. Because it doesn't depend on MIGRATE_CMA pageblocks and the
associated infrastructure, it is possible with few simple adjustments to
require only CONFIG_MEMORY_ISOLATION instead of full CONFIG_CMA.
After this patch, alloc_contig_range() and related functions are
available and used for gigantic pages with just CONFIG_MEMORY_ISOLATION
enabled. Note CONFIG_CMA selects CONFIG_MEMORY_ISOLATION. This allows
supporting runtime gigantic pages without the CMA-specific checks in
page allocator fastpaths.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Attempting to preallocate 1G gigantic huge pages at boot time with
"hugepagesz=1G hugepages=1" on the kernel command line will prevent
booting with the following:
kernel BUG at mm/hugetlb.c:1218!
When mapcount accounting was reworked, the setting of
compound_mapcount_ptr in prep_compound_gigantic_page was overlooked. As
a result, the validation of mapcount in free_huge_page fails.
The "BUG_ON" checks in free_huge_page were also changed to
"VM_BUG_ON_PAGE" to assist with debugging.
Fixes: 53f9263bab ("mm: rework mapcount accounting to enable 4k mapping of THPs")
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: David Rientjes <rientjes@google.com>
Tested-by: Vlastimil Babka <vbabka@suse.cz>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We're going to allow mapping of individual 4k pages of THP compound. It
means we need to track mapcount on per small page basis.
Straight-forward approach is to use ->_mapcount in all subpages to track
how many time this subpage is mapped with PMDs or PTEs combined. But
this is rather expensive: mapping or unmapping of a THP page with PMD
would require HPAGE_PMD_NR atomic operations instead of single we have
now.
The idea is to store separately how many times the page was mapped as
whole -- compound_mapcount. This frees up ->_mapcount in subpages to
track PTE mapcount.
We use the same approach as with compound page destructor and compound
order to store compound_mapcount: use space in first tail page,
->mapping this time.
Any time we map/unmap whole compound page (THP or hugetlb) -- we
increment/decrement compound_mapcount. When we map part of compound
page with PTE we operate on ->_mapcount of the subpage.
page_mapcount() counts both: PTE and PMD mappings of the page.
Basically, we have mapcount for a subpage spread over two counters. It
makes tricky to detect when last mapcount for a page goes away.
We introduced PageDoubleMap() for this. When we split THP PMD for the
first time and there's other PMD mapping left we offset up ->_mapcount
in all subpages by one and set PG_double_map on the compound page.
These additional references go away with last compound_mapcount.
This approach provides a way to detect when last mapcount goes away on
per small page basis without introducing new overhead for most common
cases.
[akpm@linux-foundation.org: fix typo in comment]
[mhocko@suse.com: ignore partial THP when moving task]
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Jerome Marchand <jmarchan@redhat.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
