linux-stable.git/arch/mips/include/asm/pgalloc.h, branch v4.14.331

Revert "MIPS: add PMD table accounting into MIPS'pmd_alloc_one"

2021-07-28T09:12:18+00:00

This reverts commit 920a42d8b854b1f112aef97a21f0549918889442 which is
commit commit ed914d48b6a1040d1039d371b56273d422c0081e upstream.

Commit b2b29d6d011944 (mm: account PMD tables like PTE tables) is
introduced between v5.9 and v5.10, so this fix (commit 002d8b395fa1)
should NOT apply to any pre-5.10 branch.

Signed-off-by: Huang Pei 
Signed-off-by: Greg Kroah-Hartman

MIPS: add PMD table accounting into MIPS'pmd_alloc_one

2021-07-20T14:17:44+00:00

[ Upstream commit ed914d48b6a1040d1039d371b56273d422c0081e ]

This fixes Page Table accounting bug.

MIPS is the ONLY arch just defining __HAVE_ARCH_PMD_ALLOC_ONE alone.
Since commit b2b29d6d011944 (mm: account PMD tables like PTE tables),
"pmd_free" in asm-generic with PMD table accounting and "pmd_alloc_one"
in MIPS without PMD table accounting causes PageTable accounting number
negative, which read by global_zone_page_state(), always returns 0.

Signed-off-by: Huang Pei 
Signed-off-by: Thomas Bogendoerfer 
Signed-off-by: Sasha Levin

MIPS: do not use __GFP_REPEAT for order-0 request

2017-07-12T23:26:03+00:00

Patch series "mm: give __GFP_REPEAT a better semantic".

The main motivation for the change is that the current implementation of
__GFP_REPEAT is not very much useful.

The documentation says:
 * __GFP_REPEAT: Try hard to allocate the memory, but the allocation attempt
 *   _might_ fail.  This depends upon the particular VM implementation.

It just fails to mention that this is true only for large (costly) high
order which has been the case since the flag was introduced.  A similar
semantic would be really helpful for smal orders as well, though,
because we have places where a failure with a specific fallback error
handling is preferred to a potential endless loop inside the page
allocator.

The earlier cleanup dropped __GFP_REPEAT usage for low (!costly) order
users so only those which might use larger orders have stayed.  One new
user added in the meantime is addressed in patch 1.

Let's rename the flag to something more verbose and use it for existing
users.  Semantic for those will not change.  Then implement low
(!costly) orders failure path which is hit after the page allocator is
about to invoke the oom killer.  With that we have a good counterpart
for __GFP_NORETRY and finally can tell try as hard as possible without
the OOM killer.

Xfs code already has an existing annotation for allocations which are
allowed to fail and we can trivially map them to the new gfp flag
because it will provide the semantic KM_MAYFAIL wants.  Christoph didn't
consider the new flag really necessary but didn't respond to the OOM
killer aspect of the change so I have kept the patch.  If this is still
seen as not really needed I can drop the patch.

kvmalloc will allow also !costly high order allocations to retry hard
before falling back to the vmalloc.

drm/i915 asked for the new semantic explicitly.

Memory migration code, especially for the memory hotplug, should back
off rather than invoking the OOM killer as well.

This patch (of 6):

Commit 3377e227af44 ("MIPS: Add 48-bit VA space (and 4-level page
tables) for 4K pages.") has added a new __GFP_REPEAT user but using this
flag doesn't really make any sense for order-0 request which is the case
here because PUD_ORDER is 0.  __GFP_REPEAT has historically effect only
on allocation requests with order > PAGE_ALLOC_COSTLY_ORDER.

This doesn't introduce any functional change.  This is a preparatory
patch for later work which renames the flag and redefines its semantic.

Link: http://lkml.kernel.org/r/20170623085345.11304-2-mhocko@kernel.org
Signed-off-by: Michal Hocko 
Acked-by: Vlastimil Babka 
Cc: Alex Belits 
Cc: David Daney 
Cc: Ralf Baechle 
Cc: Johannes Weiner 
Cc: Mel Gorman 
Cc: NeilBrown 
Cc: Christoph Hellwig 
Cc: Chris Wilson 
Cc: Darrick J. Wong 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

MIPS: Add 48-bit VA space (and 4-level page tables) for 4K pages.

2017-04-10T09:56:06+00:00

Some users must have 4K pages while needing a 48-bit VA space size.
The cleanest way do do this is to go to a 4-level page table for this
case.  Each page table level using order-0 pages adds 9 bits to the
VA size (at 4K pages, so for four levels we get 9 * 4 + 12 == 48-bits.

For the 4K page size case only we add support functions for the PUD
level of the page table tree, also the TLB exception handlers get an
extra level of tree walk.

[david.daney@cavium.com: Forward port to v4.10.]
[david.daney@cavium.com: Forward port to v4.11.]

Signed-off-by: Alex Belits 
Signed-off-by: David Daney 
Cc: James Hogan 
Cc: Alex Belits 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/15312/
Signed-off-by: Ralf Baechle

MIPS: Move pgd_alloc() out of header

2017-02-02T15:06:26+00:00

pgd_alloc() references init_mm which is not exported to modules. In
order for KVM to be able to use pgd_alloc() to allocate GVA page tables,
move pgd_alloc() into a new pgtable.c file and export it to modules.

Signed-off-by: James Hogan 
Acked-by: Ralf Baechle 
Cc: Ralf Baechle 
Cc: Paolo Bonzini 
Cc: "Radim Krčmář" 
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org

MIPS: Squash lines for simple wrapper functions

2016-10-04T14:13:57+00:00

Remove unneeded variables and assignments.

Signed-off-by: Masahiro Yamada 
Cc: Boris Brezillon 
Cc: Brian Norris 
Cc: Michal Hocko 
Cc: Andrew Morton 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14260/
Signed-off-by: Ralf Baechle

mips: get rid of superfluous __GFP_REPEAT

2016-06-25T00:23:52+00:00

__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.

pte_alloc_one{_kernel}, pmd_alloc_one allocate PTE_ORDER resp.
PMD_ORDER but both are not larger than 1.  This means that this flag has
never been actually useful here because it has always been used only for
PAGE_ALLOC_COSTLY requests.

Link: http://lkml.kernel.org/r/1464599699-30131-8-git-send-email-mhocko@kernel.org
Signed-off-by: Michal Hocko 
Cc: John Crispin 
Cc: Ralf Baechle 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mips: handle pgtable_page_ctor() fail

2013-11-15T00:32:18+00:00

Signed-off-by: Kirill A. Shutemov 
Cc: Ralf Baechle 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

MIPS: Two-level pagetables for 64-bit kernels with 64KB pages.

2010-02-27T11:53:03+00:00

For 64-bit kernels with 64KB pages and two level page tables, there are
42 bits worth of virtual address space This is larger than the 40 bits of
virtual address space obtained with the default 4KB Page size and three
levels, so there are no draw backs for using two level tables with this
configuration.

Signed-off-by: David Daney 
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/761/
Signed-off-by: Ralf Baechle

mm: Remove duplicate definitions in MIPS and SH

2009-07-28T00:26:44+00:00

Those definitions are already provided by asm-generic

Signed-off-by: Benjamin Herrenschmidt 
Acked-by: Paul Mundt 
Signed-off-by: Linus Torvalds