The help describing the memory model selection is outdated. It still says
that SPARSEMEM is experimental and DISCONTIGMEM is a preferred over
SPARSEMEM.
Update the help text for the relevant options:
* add a generic help for the "Memory Model" prompt
* add description for FLATMEM
* reduce the description of DISCONTIGMEM and add a deprecation note
* prefer SPARSEMEM over DISCONTIGMEM
Link: http://lkml.kernel.org/r/1556188531-20728-1-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.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>
Most architectures do not need the memblock memory after the page
allocator is initialized, but only few enable ARCH_DISCARD_MEMBLOCK in the
arch Kconfig.
Replacing ARCH_DISCARD_MEMBLOCK with ARCH_KEEP_MEMBLOCK and inverting the
logic makes it clear which architectures actually use memblock after
system initialization and skips the necessity to add ARCH_DISCARD_MEMBLOCK
to the architectures that are still missing that option.
Link: http://lkml.kernel.org/r/1556102150-32517-1-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add 2 new Kconfig variables that are not used by anyone. I check that
various make ARCH=somearch allmodconfig do work and do not complain. This
new Kconfig needs to be added first so that device drivers that depend on
HMM can be updated.
Once drivers are updated then I can update the HMM Kconfig to depend on
this new Kconfig in a followup patch.
This is about solving Kconfig for HMM given that device driver are
going through their own tree we want to avoid changing them from the mm
tree. So plan is:
1 - Kernel release N add the new Kconfig to mm/Kconfig (this patch)
2 - Kernel release N+1 update driver to depend on new Kconfig ie
stop using ARCH_HASH_HMM and start using ARCH_HAS_HMM_MIRROR
and ARCH_HAS_HMM_DEVICE (one or the other or both depending
on the driver)
3 - Kernel release N+2 remove ARCH_HASH_HMM and do final Kconfig
update in mm/Kconfig
Link: http://lkml.kernel.org/r/20190417211141.17580-1-jglisse@redhat.com
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Leon Romanovsky <leonro@mellanox.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
'default n' is the default value for any bool or tristate Kconfig
setting so there is no need to write it explicitly.
Also since commit f467c5640c ("kconfig: only write '# CONFIG_FOO
is not set' for visible symbols") the Kconfig behavior is the same
regardless of 'default n' being present or not:
...
One side effect of (and the main motivation for) this change is making
the following two definitions behave exactly the same:
config FOO
bool
config FOO
bool
default n
With this change, neither of these will generate a
'# CONFIG_FOO is not set' line (assuming FOO isn't selected/implied).
That might make it clearer to people that a bare 'default n' is
redundant.
...
Link: http://lkml.kernel.org/r/c3385916-e4d4-37d3-b330-e6b7dff83a52@samsung.com
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
To avoid random config build issue, select mmu notifier when HMM is
selected. In any cases when HMM get selected it will be by users that
will also wants the mmu notifier.
Link: http://lkml.kernel.org/r/20190403193318.16478-2-jglisse@redhat.com
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Souptick Joarder <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This condition allows to define alloc_contig_range, so simplify it into a
more accurate naming.
Link: http://lkml.kernel.org/r/20190327063626.18421-4-alex@ghiti.fr
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andy Lutomirsky <luto@kernel.org>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace jhash2 with xxhash.
Perf numbers:
Intel(R) Xeon(R) CPU E5-2420 v2 @ 2.20GHz
ksm: crc32c hash() 12081 MB/s
ksm: xxh64 hash() 8770 MB/s
ksm: xxh32 hash() 4529 MB/s
ksm: jhash2 hash() 1569 MB/s
Sioh Lee did some testing:
crc32c_intel: 1084.10ns
crc32c (no hardware acceleration): 7012.51ns
xxhash32: 2227.75ns
xxhash64: 1413.16ns
jhash2: 5128.30ns
As jhash2 always will be slower (for data size like PAGE_SIZE). Don't use
it in ksm at all.
Use only xxhash for now, because for using crc32c, cryptoapi must be
initialized first - that requires some tricky solution to work well in all
situations.
Link: http://lkml.kernel.org/r/20181023182554.23464-3-nefelim4ag@gmail.com
Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>
Signed-off-by: leesioh <solee@os.korea.ac.kr>
Reviewed-by: Pavel Tatashin <pavel.tatashin@microsoft.com>
Reviewed-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
All architecures use memblock for early memory management. There is no need
for the CONFIG_HAVE_MEMBLOCK configuration option.
[rppt@linux.vnet.ibm.com: of/fdt: fixup #ifdefs]
Link: http://lkml.kernel.org/r/20180919103457.GA20545@rapoport-lnx
[rppt@linux.vnet.ibm.com: csky: fixups after bootmem removal]
Link: http://lkml.kernel.org/r/20180926112744.GC4628@rapoport-lnx
[rppt@linux.vnet.ibm.com: remove stale #else and the code it protects]
Link: http://lkml.kernel.org/r/1538067825-24835-1-git-send-email-rppt@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1536927045-23536-4-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Tested-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Serge Semin <fancer.lancer@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
All achitectures select NO_BOOTMEM which essentially becomes 'Y' for any
kernel configuration and therefore it can be removed.
[alexander.h.duyck@linux.intel.com: remove now defunct NO_BOOTMEM from depends list for deferred init]
Link: http://lkml.kernel.org/r/20180925201814.3576.15105.stgit@localhost.localdomain
Link: http://lkml.kernel.org/r/1536927045-23536-3-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Serge Semin <fancer.lancer@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
All users have now been converted to the XArray. Removing the support
reduces code size and ensures new users will use the XArray instead.
Signed-off-by: Matthew Wilcox <willy@infradead.org>
CONFIG_THP_SWAP should depend on CONFIG_SWAP, because it's unreasonable
to optimize swapping for THP (Transparent Huge Page) without basic
swapping support.
In original code, when CONFIG_SWAP=n and CONFIG_THP_SWAP=y,
split_swap_cluster() will not be built because it is in swapfile.c, but
it will be called in huge_memory.c. This doesn't trigger a build error
in practice because the call site is enclosed by PageSwapCache(), which
is defined to be constant 0 when CONFIG_SWAP=n. But this is fragile and
should be fixed.
The comments are fixed too to reflect the latest progress.
Link: http://lkml.kernel.org/r/20180713021228.439-1-ying.huang@intel.com
Fixes: 38d8b4e6bd ("mm, THP, swap: delay splitting THP during swap out")
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Zi Yan <zi.yan@cs.rutgers.edu>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rename new_sparse_init() to sparse_init() which enables it. Delete old
sparse_init() and all the code that became obsolete with.
[pasha.tatashin@oracle.com: remove unused sparse_mem_maps_populate_node()]
Link: http://lkml.kernel.org/r/20180716174447.14529-6-pasha.tatashin@oracle.com
Link: http://lkml.kernel.org/r/20180712203730.8703-6-pasha.tatashin@oracle.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Tested-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc]
Tested-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Pasha Tatashin <Pavel.Tatashin@microsoft.com>
Cc: Abdul Haleem <abdhalee@linux.vnet.ibm.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Souptick Joarder <jrdr.linux@gmail.com>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The deferred memory initialization relies on section definitions, e.g
PAGES_PER_SECTION, that are only available when CONFIG_SPARSEMEM=y on
most architectures.
Initially DEFERRED_STRUCT_PAGE_INIT depended on explicit
ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT configuration option, but since
the commit 2e3ca40f03 ("mm: relax deferred struct page
requirements") this requirement was relaxed and now it is possible to
enable DEFERRED_STRUCT_PAGE_INIT on architectures that support
DISCONTINGMEM and NO_BOOTMEM which causes build failures.
For instance, setting SMP=y and DEFERRED_STRUCT_PAGE_INIT=y on arc
causes the following build failure:
CC mm/page_alloc.o
mm/page_alloc.c: In function 'update_defer_init':
mm/page_alloc.c:321:14: error: 'PAGES_PER_SECTION'
undeclared (first use in this function); did you mean 'USEC_PER_SEC'?
(pfn & (PAGES_PER_SECTION - 1)) == 0) {
^~~~~~~~~~~~~~~~~
USEC_PER_SEC
mm/page_alloc.c:321:14: note: each undeclared identifier is reported only once for each function it appears in
In file included from include/linux/cache.h:5:0,
from include/linux/printk.h:9,
from include/linux/kernel.h:14,
from include/asm-generic/bug.h:18,
from arch/arc/include/asm/bug.h:32,
from include/linux/bug.h:5,
from include/linux/mmdebug.h:5,
from include/linux/mm.h:9,
from mm/page_alloc.c:18:
mm/page_alloc.c: In function 'deferred_grow_zone':
mm/page_alloc.c:1624:52: error: 'PAGES_PER_SECTION' undeclared (first use in this function); did you mean 'USEC_PER_SEC'?
unsigned long nr_pages_needed = ALIGN(1 << order, PAGES_PER_SECTION);
^
include/uapi/linux/kernel.h:11:47: note: in definition of macro '__ALIGN_KERNEL_MASK'
#define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask))
^~~~
include/linux/kernel.h:58:22: note: in expansion of macro '__ALIGN_KERNEL'
#define ALIGN(x, a) __ALIGN_KERNEL((x), (a))
^~~~~~~~~~~~~~
mm/page_alloc.c:1624:34: note: in expansion of macro 'ALIGN'
unsigned long nr_pages_needed = ALIGN(1 << order, PAGES_PER_SECTION);
^~~~~
In file included from include/asm-generic/bug.h:18:0,
from arch/arc/include/asm/bug.h:32,
from include/linux/bug.h:5,
from include/linux/mmdebug.h:5,
from include/linux/mm.h:9,
from mm/page_alloc.c:18:
mm/page_alloc.c: In function 'free_area_init_node':
mm/page_alloc.c:6379:50: error: 'PAGES_PER_SECTION' undeclared (first use in this function); did you mean 'USEC_PER_SEC'?
pgdat->static_init_pgcnt = min_t(unsigned long, PAGES_PER_SECTION,
^
include/linux/kernel.h:812:22: note: in definition of macro '__typecheck'
(!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
^
include/linux/kernel.h:836:24: note: in expansion of macro '__safe_cmp'
__builtin_choose_expr(__safe_cmp(x, y), \
^~~~~~~~~~
include/linux/kernel.h:904:27: note: in expansion of macro '__careful_cmp'
#define min_t(type, x, y) __careful_cmp((type)(x), (type)(y), <)
^~~~~~~~~~~~~
mm/page_alloc.c:6379:29: note: in expansion of macro 'min_t'
pgdat->static_init_pgcnt = min_t(unsigned long, PAGES_PER_SECTION,
^~~~~
include/linux/kernel.h:836:2: error: first argument to '__builtin_choose_expr' not a constant
__builtin_choose_expr(__safe_cmp(x, y), \
^
include/linux/kernel.h:904:27: note: in expansion of macro '__careful_cmp'
#define min_t(type, x, y) __careful_cmp((type)(x), (type)(y), <)
^~~~~~~~~~~~~
mm/page_alloc.c:6379:29: note: in expansion of macro 'min_t'
pgdat->static_init_pgcnt = min_t(unsigned long, PAGES_PER_SECTION,
^~~~~
scripts/Makefile.build:317: recipe for target 'mm/page_alloc.o' failed
Let's make the DEFERRED_STRUCT_PAGE_INIT explicitly depend on SPARSEMEM
as the systems that support DISCONTIGMEM do not seem to have that huge
amounts of memory that would make DEFERRED_STRUCT_PAGE_INIT relevant.
Link: http://lkml.kernel.org/r/1530279308-24988-1-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Pasha Tatashin <Pavel.Tatashin@microsoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This moves all the options under a proper menu.
Based on a patch from Randy Dunlap.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
* DAX broke a fundamental assumption of truncate of file mapped pages.
The truncate path assumed that it is safe to disconnect a pinned page
from a file and let the filesystem reclaim the physical block. With DAX
the page is equivalent to the filesystem block. Introduce
dax_layout_busy_page() to enable filesystems to wait for pinned DAX
pages to be released. Without this wait a filesystem could allocate
blocks under active device-DMA to a new file.
* DAX arranges for the block layer to be bypassed and uses
dax_direct_access() + copy_to_iter() to satisfy read(2) calls.
However, the memcpy_mcsafe() facility is available through the pmem
block driver. In order to safely handle media errors, via the DAX
block-layer bypass, introduce copy_to_iter_mcsafe().
* Fix cache management policy relative to the ACPI NFIT Platform
Capabilities Structure to properly elide cache flushes when they are not
necessary. The table indicates whether CPU caches are power-fail
protected. Clarify that a deep flush is always performed on
REQ_{FUA,PREFLUSH} requests.
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Merge tag 'libnvdimm-for-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updates from Dan Williams:
"This adds a user for the new 'bytes-remaining' updates to
memcpy_mcsafe() that you already received through Ingo via the
x86-dax- for-linus pull.
Not included here, but still targeting this cycle, is support for
handling memory media errors (poison) consumed via userspace dax
mappings.
Summary:
- DAX broke a fundamental assumption of truncate of file mapped
pages. The truncate path assumed that it is safe to disconnect a
pinned page from a file and let the filesystem reclaim the physical
block. With DAX the page is equivalent to the filesystem block.
Introduce dax_layout_busy_page() to enable filesystems to wait for
pinned DAX pages to be released. Without this wait a filesystem
could allocate blocks under active device-DMA to a new file.
- DAX arranges for the block layer to be bypassed and uses
dax_direct_access() + copy_to_iter() to satisfy read(2) calls.
However, the memcpy_mcsafe() facility is available through the pmem
block driver. In order to safely handle media errors, via the DAX
block-layer bypass, introduce copy_to_iter_mcsafe().
- Fix cache management policy relative to the ACPI NFIT Platform
Capabilities Structure to properly elide cache flushes when they
are not necessary. The table indicates whether CPU caches are
power-fail protected. Clarify that a deep flush is always performed
on REQ_{FUA,PREFLUSH} requests"
* tag 'libnvdimm-for-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (21 commits)
dax: Use dax_write_cache* helpers
libnvdimm, pmem: Do not flush power-fail protected CPU caches
libnvdimm, pmem: Unconditionally deep flush on *sync
libnvdimm, pmem: Complete REQ_FLUSH => REQ_PREFLUSH
acpi, nfit: Remove ecc_unit_size
dax: dax_insert_mapping_entry always succeeds
libnvdimm, e820: Register all pmem resources
libnvdimm: Debug probe times
linvdimm, pmem: Preserve read-only setting for pmem devices
x86, nfit_test: Add unit test for memcpy_mcsafe()
pmem: Switch to copy_to_iter_mcsafe()
dax: Report bytes remaining in dax_iomap_actor()
dax: Introduce a ->copy_to_iter dax operation
uio, lib: Fix CONFIG_ARCH_HAS_UACCESS_MCSAFE compilation
xfs, dax: introduce xfs_break_dax_layouts()
xfs: prepare xfs_break_layouts() for another layout type
xfs: prepare xfs_break_layouts() to be called with XFS_MMAPLOCK_EXCL
mm, fs, dax: handle layout changes to pinned dax mappings
mm: fix __gup_device_huge vs unmap
mm: introduce MEMORY_DEVICE_FS_DAX and CONFIG_DEV_PAGEMAP_OPS
...
Currently the PTE special supports is turned on in per architecture
header files. Most of the time, it is defined in
arch/*/include/asm/pgtable.h depending or not on some other per
architecture static definition.
This patch introduce a new configuration variable to manage this
directly in the Kconfig files. It would later replace
__HAVE_ARCH_PTE_SPECIAL.
Here notes for some architecture where the definition of
__HAVE_ARCH_PTE_SPECIAL is not obvious:
arm
__HAVE_ARCH_PTE_SPECIAL which is currently defined in
arch/arm/include/asm/pgtable-3level.h which is included by
arch/arm/include/asm/pgtable.h when CONFIG_ARM_LPAE is set.
So select ARCH_HAS_PTE_SPECIAL if ARM_LPAE.
powerpc
__HAVE_ARCH_PTE_SPECIAL is defined in 2 files:
- arch/powerpc/include/asm/book3s/64/pgtable.h
- arch/powerpc/include/asm/pte-common.h
The first one is included if (PPC_BOOK3S & PPC64) while the second is
included in all the other cases.
So select ARCH_HAS_PTE_SPECIAL all the time.
sparc:
__HAVE_ARCH_PTE_SPECIAL is defined if defined(__sparc__) &&
defined(__arch64__) which are defined through the compiler in
sparc/Makefile if !SPARC32 which I assume to be if SPARC64.
So select ARCH_HAS_PTE_SPECIAL if SPARC64
There is no functional change introduced by this patch.
Link: http://lkml.kernel.org/r/1523433816-14460-2-git-send-email-ldufour@linux.vnet.ibm.com
Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Suggested-by: Jerome Glisse <jglisse@redhat.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Albert Ou <albert@sifive.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Christophe LEROY <christophe.leroy@c-s.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
including:
- Extensive RST conversions and organizational work in the
memory-management docs thanks to Mike Rapoport.
- An update of Documentation/features from Andrea Parri and a script to
keep it updated.
- Various LICENSES updates from Thomas, along with a script to check SPDX
tags.
- Work to fix dangling references to documentation files; this involved a
fair number of one-liner comment changes outside of Documentation/
...and the usual list of documentation improvements, typo fixes, etc.
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Merge tag 'docs-4.18' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
"There's been a fair amount of work in the docs tree this time around,
including:
- Extensive RST conversions and organizational work in the
memory-management docs thanks to Mike Rapoport.
- An update of Documentation/features from Andrea Parri and a script
to keep it updated.
- Various LICENSES updates from Thomas, along with a script to check
SPDX tags.
- Work to fix dangling references to documentation files; this
involved a fair number of one-liner comment changes outside of
Documentation/
... and the usual list of documentation improvements, typo fixes, etc"
* tag 'docs-4.18' of git://git.lwn.net/linux: (103 commits)
Documentation: document hung_task_panic kernel parameter
docs/admin-guide/mm: add high level concepts overview
docs/vm: move ksm and transhuge from "user" to "internals" section.
docs: Use the kerneldoc comments for memalloc_no*()
doc: document scope NOFS, NOIO APIs
docs: update kernel versions and dates in tables
docs/vm: transhuge: split userspace bits to admin-guide/mm/transhuge
docs/vm: transhuge: minor updates
docs/vm: transhuge: change sections order
Documentation: arm: clean up Marvell Berlin family info
Documentation: gpio: driver: Fix a typo and some odd grammar
docs: ranoops.rst: fix location of ramoops.txt
scripts/documentation-file-ref-check: rewrite it in perl with auto-fix mode
docs: uio-howto.rst: use a code block to solve a warning
mm, THP, doc: Add document for thp_swpout/thp_swpout_fallback
w1: w1_io.c: fix a kernel-doc warning
Documentation/process/posting: wrap text at 80 cols
docs: admin-guide: add cgroup-v2 documentation
Revert "Documentation/features/vm: Remove arch support status file for 'pte_special'"
Documentation: refcount-vs-atomic: Update reference to LKMM doc.
...
- replaceme the force_dma flag with a dma_configure bus method.
(Nipun Gupta, although one patch is іncorrectly attributed to me
due to a git rebase bug)
- use GFP_DMA32 more agressively in dma-direct. (Takashi Iwai)
- remove PCI_DMA_BUS_IS_PHYS and rely on the dma-mapping API to do the
right thing for bounce buffering.
- move dma-debug initialization to common code, and apply a few cleanups
to the dma-debug code.
- cleanup the Kconfig mess around swiotlb selection
- swiotlb comment fixup (Yisheng Xie)
- a trivial swiotlb fix. (Dan Carpenter)
- support swiotlb on RISC-V. (based on a patch from Palmer Dabbelt)
- add a new generic dma-noncoherent dma_map_ops implementation and use
it for arc, c6x and nds32.
- improve scatterlist validity checking in dma-debug. (Robin Murphy)
- add a struct device quirk to limit the dma-mask to 32-bit due to
bridge/system issues, and switch x86 to use it instead of a local
hack for VIA bridges.
- handle devices without a dma_mask more gracefully in the dma-direct
code.
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Merge tag 'dma-mapping-4.18' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping updates from Christoph Hellwig:
- replace the force_dma flag with a dma_configure bus method. (Nipun
Gupta, although one patch is іncorrectly attributed to me due to a
git rebase bug)
- use GFP_DMA32 more agressively in dma-direct. (Takashi Iwai)
- remove PCI_DMA_BUS_IS_PHYS and rely on the dma-mapping API to do the
right thing for bounce buffering.
- move dma-debug initialization to common code, and apply a few
cleanups to the dma-debug code.
- cleanup the Kconfig mess around swiotlb selection
- swiotlb comment fixup (Yisheng Xie)
- a trivial swiotlb fix. (Dan Carpenter)
- support swiotlb on RISC-V. (based on a patch from Palmer Dabbelt)
- add a new generic dma-noncoherent dma_map_ops implementation and use
it for arc, c6x and nds32.
- improve scatterlist validity checking in dma-debug. (Robin Murphy)
- add a struct device quirk to limit the dma-mask to 32-bit due to
bridge/system issues, and switch x86 to use it instead of a local
hack for VIA bridges.
- handle devices without a dma_mask more gracefully in the dma-direct
code.
* tag 'dma-mapping-4.18' of git://git.infradead.org/users/hch/dma-mapping: (48 commits)
dma-direct: don't crash on device without dma_mask
nds32: use generic dma_noncoherent_ops
nds32: implement the unmap_sg DMA operation
nds32: consolidate DMA cache maintainance routines
x86/pci-dma: switch the VIA 32-bit DMA quirk to use the struct device flag
x86/pci-dma: remove the explicit nodac and allowdac option
x86/pci-dma: remove the experimental forcesac boot option
Documentation/x86: remove a stray reference to pci-nommu.c
core, dma-direct: add a flag 32-bit dma limits
dma-mapping: remove unused gfp_t parameter to arch_dma_alloc_attrs
dma-debug: check scatterlist segments
c6x: use generic dma_noncoherent_ops
arc: use generic dma_noncoherent_ops
arc: fix arc_dma_{map,unmap}_page
arc: fix arc_dma_sync_sg_for_{cpu,device}
arc: simplify arc_dma_sync_single_for_{cpu,device}
dma-mapping: provide a generic dma-noncoherent implementation
dma-mapping: simplify Kconfig dependencies
riscv: add swiotlb support
riscv: only enable ZONE_DMA32 for 64-bit
...
In preparation for fixing dax-dma-vs-unmap issues, filesystems need to
be able to rely on the fact that they will get wakeups on dev_pagemap
page-idle events. Introduce MEMORY_DEVICE_FS_DAX and
generic_dax_page_free() as common indicator / infrastructure for dax
filesytems to require. With this change there are no users of the
MEMORY_DEVICE_HOST designation, so remove it.
The HMM sub-system extended dev_pagemap to arrange a callback when a
dev_pagemap managed page is freed. Since a dev_pagemap page is free /
idle when its reference count is 1 it requires an additional branch to
check the page-type at put_page() time. Given put_page() is a hot-path
we do not want to incur that check if HMM is not in use, so a static
branch is used to avoid that overhead when not necessary.
Now, the FS_DAX implementation wants to reuse this mechanism for
receiving dev_pagemap ->page_free() callbacks. Rework the HMM-specific
static-key into a generic mechanism that either HMM or FS_DAX code paths
can enable.
For ARCH=um builds, and any other arch that lacks ZONE_DEVICE support,
care must be taken to compile out the DEV_PAGEMAP_OPS infrastructure.
However, we still need to support FS_DAX in the FS_DAX_LIMITED case
implemented by the s390/dcssblk driver.
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Michal Hocko <mhocko@suse.com>
Reported-by: kbuild test robot <lkp@intel.com>
Reported-by: Thomas Meyer <thomas@m3y3r.de>
Reported-by: Dave Jiang <dave.jiang@intel.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
It is unsafe to do virtual to physical translations before mm_init() is
called if struct page is needed in order to determine the memory section
number (see SECTION_IN_PAGE_FLAGS). This is because only in mm_init()
we initialize struct pages for all the allocated memory when deferred
struct pages are used.
My recent fix in commit c9e97a1997 ("mm: initialize pages on demand
during boot") exposed this problem, because it greatly reduced number of
pages that are initialized before mm_init(), but the problem existed
even before my fix, as Fengguang Wu found.
Below is a more detailed explanation of the problem.
We initialize struct pages in four places:
1. Early in boot a small set of struct pages is initialized to fill the
first section, and lower zones.
2. During mm_init() we initialize "struct pages" for all the memory that
is allocated, i.e reserved in memblock.
3. Using on-demand logic when pages are allocated after mm_init call
(when memblock is finished)
4. After smp_init() when the rest free deferred pages are initialized.
The problem occurs if we try to do va to phys translation of a memory
between steps 1 and 2. Because we have not yet initialized struct pages
for all the reserved pages, it is inherently unsafe to do va to phys if
the translation itself requires access of "struct page" as in case of
this combination: CONFIG_SPARSE && !CONFIG_SPARSE_VMEMMAP
The following path exposes the problem:
start_kernel()
trap_init()
setup_cpu_entry_areas()
setup_cpu_entry_area(cpu)
get_cpu_gdt_paddr(cpu)
per_cpu_ptr_to_phys(addr)
pcpu_addr_to_page(addr)
virt_to_page(addr)
pfn_to_page(__pa(addr) >> PAGE_SHIFT)
We disable this path by not allowing NEED_PER_CPU_KM with deferred
struct pages feature.
The problems are discussed in these threads:
http://lkml.kernel.org/r/20180418135300.inazvpxjxowogyge@wfg-t540p.sh.intel.comhttp://lkml.kernel.org/r/20180419013128.iurzouiqxvcnpbvz@wfg-t540p.sh.intel.comhttp://lkml.kernel.org/r/20180426202619.2768-1-pasha.tatashin@oracle.com
Link: http://lkml.kernel.org/r/20180515175124.1770-1-pasha.tatashin@oracle.com
Fixes: 3a80a7fa79 ("mm: meminit: initialise a subset of struct pages if CONFIG_DEFERRED_STRUCT_PAGE_INIT is set")
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Dennis Zhou <dennisszhou@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Instead select the PHYS_ADDR_T_64BIT for 32-bit architectures that need a
64-bit phys_addr_t type directly.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: James Hogan <jhogan@kernel.org>
Several documents in Documentation/vm fit quite well into the "admin/user
guide" category. The documents that don't overload the reader with lots of
implementation details and provide coherent description of certain feature
can be moved to Documentation/admin-guide/mm.
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Mike Rapoport says:
These patches convert files in Documentation/vm to ReST format, add an
initial index and link it to the top level documentation.
There are no contents changes in the documentation, except few spelling
fixes. The relatively large diffstat stems from the indentation and
paragraph wrapping changes.
I've tried to keep the formatting as consistent as possible, but I could
miss some places that needed markup and add some markup where it was not
necessary.
[jc: significant conflicts in vm/hmm.rst]
A lot of Kconfig symbols have architecture specific dependencies.
In those cases that depend on architectures we have already removed,
they can be omitted.
Acked-by: Kalle Valo <kvalo@codeaurora.org>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Now that arch/metag/ has been removed, drop a bunch of metag references
in various codes across the whole tree:
- VM_GROWSUP and __VM_ARCH_SPECIFIC_1.
- MT_METAG_* ELF note types.
- METAG Kconfig dependencies (FRAME_POINTER) and ranges
(MAX_STACK_SIZE_MB).
- metag cases in tools (checkstack.pl, recordmcount.c, perf).
Signed-off-by: James Hogan <jhogan@kernel.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: linux-mm@kvack.org
Cc: linux-metag@vger.kernel.org
There is no need to have ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT, as all
the page initialization code is in common code.
Also, there is no need to depend on MEMORY_HOTPLUG, as initialization
code does not really use hotplug memory functionality. So, we can
remove this requirement as well.
This patch allows to use deferred struct page initialization on all
platforms with memblock allocator.
Tested on x86, arm64, and sparc. Also, verified that code compiles on
PPC with CONFIG_MEMORY_HOTPLUG disabled.
Link: http://lkml.kernel.org/r/20171117014601.31606-1-pasha.tatashin@oracle.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> [s390]
Reviewed-by: Khalid Aziz <khalid.aziz@oracle.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Performance of get_user_pages_fast() is critical for some workloads, but
it's tricky to test it directly.
This patch provides /sys/kernel/debug/gup_benchmark that helps with
testing performance of it.
See tools/testing/selftests/vm/gup_benchmark.c for userspace
counterpart.
Link: http://lkml.kernel.org/r/20170908215603.9189-2-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thorsten Leemhuis <regressions@leemhuis.info>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This moves all new code including new page migration helper behind kernel
Kconfig option so that there is no codee bloat for arch or user that do
not want to use HMM or any of its associated features.
arm allyesconfig (without all the patchset, then with and this patch):
text data bss dec hex filename
83721896 46511131 27582964 157815991 96814b7 ../without/vmlinux
83722364 46511131 27582964 157816459 968168b vmlinux
[jglisse@redhat.com: struct hmm is only use by HMM mirror functionality]
Link: http://lkml.kernel.org/r/20170825213133.27286-1-jglisse@redhat.com
[sfr@canb.auug.org.au: fix build (arm multi_v7_defconfig)]
Link: http://lkml.kernel.org/r/20170828181849.323ab81b@canb.auug.org.au
Link: http://lkml.kernel.org/r/20170818032858.7447-1-jglisse@redhat.com
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Platform with advance system bus (like CAPI or CCIX) allow device memory
to be accessible from CPU in a cache coherent fashion. Add a new type of
ZONE_DEVICE to represent such memory. The use case are the same as for
the un-addressable device memory but without all the corners cases.
Link: http://lkml.kernel.org/r/20170817000548.32038-19-jglisse@redhat.com
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: David Nellans <dnellans@nvidia.com>
Cc: Evgeny Baskakov <ebaskakov@nvidia.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mark Hairgrove <mhairgrove@nvidia.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Sherry Cheung <SCheung@nvidia.com>
Cc: Subhash Gutti <sgutti@nvidia.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Bob Liu <liubo95@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
HMM (heterogeneous memory management) need struct page to support
migration from system main memory to device memory. Reasons for HMM and
migration to device memory is explained with HMM core patch.
This patch deals with device memory that is un-addressable memory (ie CPU
can not access it). Hence we do not want those struct page to be manage
like regular memory. That is why we extend ZONE_DEVICE to support
different types of memory.
A persistent memory type is define for existing user of ZONE_DEVICE and a
new device un-addressable type is added for the un-addressable memory
type. There is a clear separation between what is expected from each
memory type and existing user of ZONE_DEVICE are un-affected by new
requirement and new use of the un-addressable type. All specific code
path are protect with test against the memory type.
Because memory is un-addressable we use a new special swap type for when a
page is migrated to device memory (this reduces the number of maximum swap
file).
The main two additions beside memory type to ZONE_DEVICE is two callbacks.
First one, page_free() is call whenever page refcount reach 1 (which
means the page is free as ZONE_DEVICE page never reach a refcount of 0).
This allow device driver to manage its memory and associated struct page.
The second callback page_fault() happens when there is a CPU access to an
address that is back by a device page (which are un-addressable by the
CPU). This callback is responsible to migrate the page back to system
main memory. Device driver can not block migration back to system memory,
HMM make sure that such page can not be pin into device memory.
If device is in some error condition and can not migrate memory back then
a CPU page fault to device memory should end with SIGBUS.
[arnd@arndb.de: fix warning]
Link: http://lkml.kernel.org/r/20170823133213.712917-1-arnd@arndb.de
Link: http://lkml.kernel.org/r/20170817000548.32038-8-jglisse@redhat.com
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Nellans <dnellans@nvidia.com>
Cc: Evgeny Baskakov <ebaskakov@nvidia.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mark Hairgrove <mhairgrove@nvidia.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Sherry Cheung <SCheung@nvidia.com>
Cc: Subhash Gutti <sgutti@nvidia.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Bob Liu <liubo95@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is a heterogeneous memory management (HMM) process address space
mirroring. In a nutshell this provide an API to mirror process address
space on a device. This boils down to keeping CPU and device page table
synchronize (we assume that both device and CPU are cache coherent like
PCIe device can be).
This patch provide a simple API for device driver to achieve address space
mirroring thus avoiding each device driver to grow its own CPU page table
walker and its own CPU page table synchronization mechanism.
This is useful for NVidia GPU >= Pascal, Mellanox IB >= mlx5 and more
hardware in the future.
[jglisse@redhat.com: fix hmm for "mmu_notifier kill invalidate_page callback"]
Link: http://lkml.kernel.org/r/20170830231955.GD9445@redhat.com
Link: http://lkml.kernel.org/r/20170817000548.32038-4-jglisse@redhat.com
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Signed-off-by: Evgeny Baskakov <ebaskakov@nvidia.com>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Mark Hairgrove <mhairgrove@nvidia.com>
Signed-off-by: Sherry Cheung <SCheung@nvidia.com>
Signed-off-by: Subhash Gutti <sgutti@nvidia.com>
Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Nellans <dnellans@nvidia.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Bob Liu <liubo95@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
HMM provides 3 separate types of functionality:
- Mirroring: synchronize CPU page table and device page table
- Device memory: allocating struct page for device memory
- Migration: migrating regular memory to device memory
This patch introduces some common helpers and definitions to all of
those 3 functionality.
Link: http://lkml.kernel.org/r/20170817000548.32038-3-jglisse@redhat.com
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Signed-off-by: Evgeny Baskakov <ebaskakov@nvidia.com>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Mark Hairgrove <mhairgrove@nvidia.com>
Signed-off-by: Sherry Cheung <SCheung@nvidia.com>
Signed-off-by: Subhash Gutti <sgutti@nvidia.com>
Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Nellans <dnellans@nvidia.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Bob Liu <liubo95@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Introduce CONFIG_ARCH_ENABLE_THP_MIGRATION to limit thp migration
functionality to x86_64, which should be safer at the first step.
Link: http://lkml.kernel.org/r/20170717193955.20207-5-zi.yan@sent.com
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Zi Yan <zi.yan@cs.rutgers.edu>
Reviewed-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: David Nellans <dnellans@nvidia.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
devm_memremap_pages() records mapped ranges in pgmap_radix with an entry
per section's worth of memory (128MB). The key for each of those
entries is a section number.
This leads to false positives when devm_memremap_pages() is passed a
section-unaligned range as lookups in the misalignment fail to return
NULL. We can close this hole by using the pfn as the key for entries in
the tree. The number of entries required to describe a remapped range
is reduced by leveraging multi-order entries.
In practice this approach usually yields just one entry in the tree if
the size and starting address are of the same power-of-2 alignment.
Previously we always needed nr_entries = mapping_size / 128MB.
Link: https://lists.01.org/pipermail/linux-nvdimm/2016-August/006666.html
Link: http://lkml.kernel.org/r/150215410565.39310.13767886055248249438.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reported-by: Toshi Kani <toshi.kani@hpe.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
KASAN doesn't happen work with memory hotplug because hotplugged memory
doesn't have any shadow memory. So any access to hotplugged memory
would cause a crash on shadow check.
Use memory hotplug notifier to allocate and map shadow memory when the
hotplugged memory is going online and free shadow after the memory
offlined.
Link: http://lkml.kernel.org/r/20170601162338.23540-4-aryabinin@virtuozzo.com
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Highlights include:
- Support for STRICT_KERNEL_RWX on 64-bit server CPUs.
- Platform support for FSP2 (476fpe) board
- Enable ZONE_DEVICE on 64-bit server CPUs.
- Generic & powerpc spin loop primitives to optimise busy waiting
- Convert VDSO update function to use new update_vsyscall() interface
- Optimisations to hypercall/syscall/context-switch paths
- Improvements to the CPU idle code on Power8 and Power9.
As well as many other fixes and improvements.
Thanks to:
Akshay Adiga, Andrew Donnellan, Andrew Jeffery, Anshuman Khandual, Anton
Blanchard, Balbir Singh, Benjamin Herrenschmidt, Christophe Leroy, Christophe
Lombard, Colin Ian King, Dan Carpenter, Gautham R. Shenoy, Hari Bathini, Ian
Munsie, Ivan Mikhaylov, Javier Martinez Canillas, Madhavan Srinivasan,
Masahiro Yamada, Matt Brown, Michael Neuling, Michal Suchanek, Murilo
Opsfelder Araujo, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Paul
Mackerras, Pavel Machek, Russell Currey, Santosh Sivaraj, Stephen Rothwell,
Thiago Jung Bauermann, Yang Li.
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Merge tag 'powerpc-4.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
"Highlights include:
- Support for STRICT_KERNEL_RWX on 64-bit server CPUs.
- Platform support for FSP2 (476fpe) board
- Enable ZONE_DEVICE on 64-bit server CPUs.
- Generic & powerpc spin loop primitives to optimise busy waiting
- Convert VDSO update function to use new update_vsyscall() interface
- Optimisations to hypercall/syscall/context-switch paths
- Improvements to the CPU idle code on Power8 and Power9.
As well as many other fixes and improvements.
Thanks to: Akshay Adiga, Andrew Donnellan, Andrew Jeffery, Anshuman
Khandual, Anton Blanchard, Balbir Singh, Benjamin Herrenschmidt,
Christophe Leroy, Christophe Lombard, Colin Ian King, Dan Carpenter,
Gautham R. Shenoy, Hari Bathini, Ian Munsie, Ivan Mikhaylov, Javier
Martinez Canillas, Madhavan Srinivasan, Masahiro Yamada, Matt Brown,
Michael Neuling, Michal Suchanek, Murilo Opsfelder Araujo, Naveen N.
Rao, Nicholas Piggin, Oliver O'Halloran, Paul Mackerras, Pavel Machek,
Russell Currey, Santosh Sivaraj, Stephen Rothwell, Thiago Jung
Bauermann, Yang Li"
* tag 'powerpc-4.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (158 commits)
powerpc/Kconfig: Enable STRICT_KERNEL_RWX for some configs
powerpc/mm/radix: Implement STRICT_RWX/mark_rodata_ro() for Radix
powerpc/mm/hash: Implement mark_rodata_ro() for hash
powerpc/vmlinux.lds: Align __init_begin to 16M
powerpc/lib/code-patching: Use alternate map for patch_instruction()
powerpc/xmon: Add patch_instruction() support for xmon
powerpc/kprobes/optprobes: Use patch_instruction()
powerpc/kprobes: Move kprobes over to patch_instruction()
powerpc/mm/radix: Fix execute permissions for interrupt_vectors
powerpc/pseries: Fix passing of pp0 in updatepp() and updateboltedpp()
powerpc/64s: Blacklist rtas entry/exit from kprobes
powerpc/64s: Blacklist functions invoked on a trap
powerpc/64s: Un-blacklist system_call() from kprobes
powerpc/64s: Move system_call() symbol to just after setting MSR_EE
powerpc/64s: Blacklist system_call() and system_call_common() from kprobes
powerpc/64s: Convert .L__replay_interrupt_return to a local label
powerpc64/elfv1: Only dereference function descriptor for non-text symbols
cxl: Export library to support IBM XSL
powerpc/dts: Use #include "..." to include local DT
powerpc/perf/hv-24x7: Aggregate result elements on POWER9 SMT8
...
Commit 20b2f52b73 ("numa: add CONFIG_MOVABLE_NODE for
movable-dedicated node") has introduced CONFIG_MOVABLE_NODE without a
good explanation on why it is actually useful.
It makes a lot of sense to make movable node semantic opt in but we
already have that because the feature has to be explicitly enabled on
the kernel command line. A config option on top only makes the
configuration space larger without a good reason. It also adds an
additional ifdefery that pollutes the code.
Just drop the config option and make it de-facto always enabled. This
shouldn't introduce any change to the semantic.
Link: http://lkml.kernel.org/r/20170529114141.536-3-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Yasuaki Ishimatsu <yasu.isimatu@gmail.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Kani Toshimitsu <toshi.kani@hpe.com>
Cc: Chen Yucong <slaoub@gmail.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Daniel Kiper <daniel.kiper@oracle.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "THP swap: Delay splitting THP during swapping out", v11.
This patchset is to optimize the performance of Transparent Huge Page
(THP) swap.
Recently, the performance of the storage devices improved so fast that
we cannot saturate the disk bandwidth with single logical CPU when do
page swap out even on a high-end server machine. Because the
performance of the storage device improved faster than that of single
logical CPU. And it seems that the trend will not change in the near
future. On the other hand, the THP becomes more and more popular
because of increased memory size. So it becomes necessary to optimize
THP swap performance.
The advantages of the THP swap support include:
- Batch the swap operations for the THP to reduce lock
acquiring/releasing, including allocating/freeing the swap space,
adding/deleting to/from the swap cache, and writing/reading the swap
space, etc. This will help improve the performance of the THP swap.
- The THP swap space read/write will be 2M sequential IO. It is
particularly helpful for the swap read, which are usually 4k random
IO. This will improve the performance of the THP swap too.
- It will help the memory fragmentation, especially when the THP is
heavily used by the applications. The 2M continuous pages will be
free up after THP swapping out.
- It will improve the THP utilization on the system with the swap
turned on. Because the speed for khugepaged to collapse the normal
pages into the THP is quite slow. After the THP is split during the
swapping out, it will take quite long time for the normal pages to
collapse back into the THP after being swapped in. The high THP
utilization helps the efficiency of the page based memory management
too.
There are some concerns regarding THP swap in, mainly because possible
enlarged read/write IO size (for swap in/out) may put more overhead on
the storage device. To deal with that, the THP swap in should be turned
on only when necessary. For example, it can be selected via
"always/never/madvise" logic, to be turned on globally, turned off
globally, or turned on only for VMA with MADV_HUGEPAGE, etc.
This patchset is the first step for the THP swap support. The plan is
to delay splitting THP step by step, finally avoid splitting THP during
the THP swapping out and swap out/in the THP as a whole.
As the first step, in this patchset, the splitting huge page is delayed
from almost the first step of swapping out to after allocating the swap
space for the THP and adding the THP into the swap cache. This will
reduce lock acquiring/releasing for the locks used for the swap cache
management.
With the patchset, the swap out throughput improves 15.5% (from about
3.73GB/s to about 4.31GB/s) in the vm-scalability swap-w-seq test case
with 8 processes. The test is done on a Xeon E5 v3 system. The swap
device used is a RAM simulated PMEM (persistent memory) device. To test
the sequential swapping out, the test case creates 8 processes, which
sequentially allocate and write to the anonymous pages until the RAM and
part of the swap device is used up.
This patch (of 5):
In this patch, splitting huge page is delayed from almost the first step
of swapping out to after allocating the swap space for the THP
(Transparent Huge Page) and adding the THP into the swap cache. This
will batch the corresponding operation, thus improve THP swap out
throughput.
This is the first step for the THP swap optimization. The plan is to
delay splitting the THP step by step and avoid splitting the THP
finally.
In this patch, one swap cluster is used to hold the contents of each THP
swapped out. So, the size of the swap cluster is changed to that of the
THP (Transparent Huge Page) on x86_64 architecture (512). For other
architectures which want such THP swap optimization,
ARCH_USES_THP_SWAP_CLUSTER needs to be selected in the Kconfig file for
the architecture. In effect, this will enlarge swap cluster size by 2
times on x86_64. Which may make it harder to find a free cluster when
the swap space becomes fragmented. So that, this may reduce the
continuous swap space allocation and sequential write in theory. The
performance test in 0day shows no regressions caused by this.
In the future of THP swap optimization, some information of the swapped
out THP (such as compound map count) will be recorded in the
swap_cluster_info data structure.
The mem cgroup swap accounting functions are enhanced to support charge
or uncharge a swap cluster backing a THP as a whole.
The swap cluster allocate/free functions are added to allocate/free a
swap cluster for a THP. A fair simple algorithm is used for swap
cluster allocation, that is, only the first swap device in priority list
will be tried to allocate the swap cluster. The function will fail if
the trying is not successful, and the caller will fallback to allocate a
single swap slot instead. This works good enough for normal cases. If
the difference of the number of the free swap clusters among multiple
swap devices is significant, it is possible that some THPs are split
earlier than necessary. For example, this could be caused by big size
difference among multiple swap devices.
The swap cache functions is enhanced to support add/delete THP to/from
the swap cache as a set of (HPAGE_PMD_NR) sub-pages. This may be
enhanced in the future with multi-order radix tree. But because we will
split the THP soon during swapping out, that optimization doesn't make
much sense for this first step.
The THP splitting functions are enhanced to support to split THP in swap
cache during swapping out. The page lock will be held during allocating
the swap cluster, adding the THP into the swap cache and splitting the
THP. So in the code path other than swapping out, if the THP need to be
split, the PageSwapCache(THP) will be always false.
The swap cluster is only available for SSD, so the THP swap optimization
in this patchset has no effect for HDD.
[ying.huang@intel.com: fix two issues in THP optimize patch]
Link: http://lkml.kernel.org/r/87k25ed8zo.fsf@yhuang-dev.intel.com
[hannes@cmpxchg.org: extensive cleanups and simplifications, reduce code size]
Link: http://lkml.kernel.org/r/20170515112522.32457-2-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Suggested-by: Andrew Morton <akpm@linux-foundation.org> [for config option]
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> [for changes in huge_memory.c and huge_mm.h]
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Ebru Akagunduz <ebru.akagunduz@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Shaohua Li <shli@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull percpu updates from Tejun Heo:
"These are the percpu changes for the v4.13-rc1 merge window. There are
a couple visibility related changes - tracepoints and allocator stats
through debugfs, along with __ro_after_init markings and a cosmetic
rename in percpu_counter.
Please note that the simple O(#elements_in_the_chunk) area allocator
used by percpu allocator is again showing scalability issues,
primarily with bpf allocating and freeing large number of counters.
Dennis is working on the replacement allocator and the percpu
allocator will be seeing increased churns in the coming cycles"
* 'for-4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
percpu: fix static checker warnings in pcpu_destroy_chunk
percpu: fix early calls for spinlock in pcpu_stats
percpu: resolve err may not be initialized in pcpu_alloc
percpu_counter: Rename __percpu_counter_add to percpu_counter_add_batch
percpu: add tracepoint support for percpu memory
percpu: expose statistics about percpu memory via debugfs
percpu: migrate percpu data structures to internal header
percpu: add missing lockdep_assert_held to func pcpu_free_area
mark most percpu globals as __ro_after_init
Currently ZONE_DEVICE depends on X86_64 and this will get unwieldly as
new architectures (and platforms) get ZONE_DEVICE support. Move to an
arch selected Kconfig option to save us the trouble.
Cc: linux-mm@kvack.org
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
There is limited visibility into the use of percpu memory leaving us
unable to reason about correctness of parameters and overall use of
percpu memory. These counters and statistics aim to help understand
basic statistics about percpu memory such as number of allocations over
the lifetime, allocation sizes, and fragmentation.
New Config: PERCPU_STATS
Signed-off-by: Dennis Zhou <dennisz@fb.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This patch provides all required callbacks required by the generic
get_user_pages_fast() code and switches x86 over - and removes
the platform specific implementation.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170606113133.22974-2-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
AVR32 architecture has been removed from the Linux kernel sources, hence
clean up the special handling setting two quicklists by default in
mm/Kconfig.
Signed-off-by: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no>
Add arch specific callback in the generic THP page cache code that will
deposit and withdarw preallocated page table. Archs like ppc64 use this
preallocated table to store the hash pte slot information.
Testing:
kernel build of the patch series on tmpfs mounted with option huge=always
The related thp stat:
thp_fault_alloc 72939
thp_fault_fallback 60547
thp_collapse_alloc 603
thp_collapse_alloc_failed 0
thp_file_alloc 253763
thp_file_mapped 4251
thp_split_page 51518
thp_split_page_failed 1
thp_deferred_split_page 73566
thp_split_pmd 665
thp_zero_page_alloc 3
thp_zero_page_alloc_failed 0
[akpm@linux-foundation.org: remove unneeded parentheses, per Kirill]
Link: http://lkml.kernel.org/r/20161113150025.17942-2-aneesh.kumar@linux.vnet.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michael Neuling <mikey@neuling.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When movable nodes are enabled, any node containing only hotpluggable
memory is made movable at boot time.
On x86, hotpluggable memory is discovered by parsing the ACPI SRAT,
making corresponding calls to memblock_mark_hotplug().
If we introduce a dt property to describe memory as hotpluggable,
configs supporting early fdt may then also do this marking and use
movable nodes.
Link: http://lkml.kernel.org/r/1479160961-25840-5-git-send-email-arbab@linux.vnet.ibm.com
Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Tested-by: Balbir Singh <bsingharora@gmail.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alistair Popple <apopple@au1.ibm.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Bharata B Rao <bharata@linux.vnet.ibm.com>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Stewart Smith <stewart@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
To support movable memory nodes (CONFIG_MOVABLE_NODE), at least one of
the following must be true:
1. This config has the capability to identify movable nodes at boot.
Right now, only x86 can do this.
2. Our config supports memory hotplug, which means that a movable node
can be created by hotplugging all of its memory into ZONE_MOVABLE.
Fix the Kconfig definition of CONFIG_MOVABLE_NODE, which currently
recognizes (1), but not (2).
Link: http://lkml.kernel.org/r/1479160961-25840-4-git-send-email-arbab@linux.vnet.ibm.com
Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alistair Popple <apopple@au1.ibm.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Bharata B Rao <bharata@linux.vnet.ibm.com>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Stewart Smith <stewart@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
No, KASAN may not be able to co-exist with HOTPLUG_MEMORY at runtime,
but for build testing there is no reason not to allow them together.
This hopefully means better build coverage and fewer embarrasing silly
problems like the one fixed by commit 9db4f36e82 ("mm: remove unused
variable in memory hotplug") in the future.
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>