Commit Graph

11605 Commits

Author SHA1 Message Date
Linus Torvalds
09b56d5a41 Merge branch 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm
Pull ARM updates from Russell King:

 - add support for ftrace-with-registers, which is needed for kgraft and
   other ftrace tools

 - support for mremap() for the sigpage/vDSO so that checkpoint/restore
   can work

 - add timestamps to each line of the register dump output

 - remove the unused KTHREAD_SIZE from nommu

 - align the ARM bitops APIs with the generic API (using unsigned long
   pointers rather than void pointers)

 - make the configuration of userspace Thumb support an expert option so
   that we can default it on, and avoid some hard to debug userspace
   crashes

* 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
  ARM: 8684/1: NOMMU: Remove unused KTHREAD_SIZE definition
  ARM: 8683/1: ARM32: Support mremap() for sigpage/vDSO
  ARM: 8679/1: bitops: Align prototypes to generic API
  ARM: 8678/1: ftrace: Adds support for CONFIG_DYNAMIC_FTRACE_WITH_REGS
  ARM: make configuration of userspace Thumb support an expert option
  ARM: 8673/1: Fix __show_regs output timestamps
2017-07-08 12:17:25 -07:00
Linus Torvalds
088737f44b Writeback error handling fixes (pile #2)
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Merge tag 'for-linus-v4.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux

Pull Writeback error handling updates from Jeff Layton:
 "This pile represents the bulk of the writeback error handling fixes
  that I have for this cycle. Some of the earlier patches in this pile
  may look trivial but they are prerequisites for later patches in the
  series.

  The aim of this set is to improve how we track and report writeback
  errors to userland. Most applications that care about data integrity
  will periodically call fsync/fdatasync/msync to ensure that their
  writes have made it to the backing store.

  For a very long time, we have tracked writeback errors using two flags
  in the address_space: AS_EIO and AS_ENOSPC. Those flags are set when a
  writeback error occurs (via mapping_set_error) and are cleared as a
  side-effect of filemap_check_errors (as you noted yesterday). This
  model really sucks for userland.

  Only the first task to call fsync (or msync or fdatasync) will see the
  error. Any subsequent task calling fsync on a file will get back 0
  (unless another writeback error occurs in the interim). If I have
  several tasks writing to a file and calling fsync to ensure that their
  writes got stored, then I need to have them coordinate with one
  another. That's difficult enough, but in a world of containerized
  setups that coordination may even not be possible.

  But wait...it gets worse!

  The calls to filemap_check_errors can be buried pretty far down in the
  call stack, and there are internal callers of filemap_write_and_wait
  and the like that also end up clearing those errors. Many of those
  callers ignore the error return from that function or return it to
  userland at nonsensical times (e.g. truncate() or stat()). If I get
  back -EIO on a truncate, there is no reason to think that it was
  because some previous writeback failed, and a subsequent fsync() will
  (incorrectly) return 0.

  This pile aims to do three things:

   1) ensure that when a writeback error occurs that that error will be
      reported to userland on a subsequent fsync/fdatasync/msync call,
      regardless of what internal callers are doing

   2) report writeback errors on all file descriptions that were open at
      the time that the error occurred. This is a user-visible change,
      but I think most applications are written to assume this behavior
      anyway. Those that aren't are unlikely to be hurt by it.

   3) document what filesystems should do when there is a writeback
      error. Today, there is very little consistency between them, and a
      lot of cargo-cult copying. We need to make it very clear what
      filesystems should do in this situation.

  To achieve this, the set adds a new data type (errseq_t) and then
  builds new writeback error tracking infrastructure around that. Once
  all of that is in place, we change the filesystems to use the new
  infrastructure for reporting wb errors to userland.

  Note that this is just the initial foray into cleaning up this mess.
  There is a lot of work remaining here:

   1) convert the rest of the filesystems in a similar fashion. Once the
      initial set is in, then I think most other fs' will be fairly
      simple to convert. Hopefully most of those can in via individual
      filesystem trees.

   2) convert internal waiters on writeback to use errseq_t for
      detecting errors instead of relying on the AS_* flags. I have some
      draft patches for this for ext4, but they are not quite ready for
      prime time yet.

  This was a discussion topic this year at LSF/MM too. If you're
  interested in the gory details, LWN has some good articles about this:

      https://lwn.net/Articles/718734/
      https://lwn.net/Articles/724307/"

* tag 'for-linus-v4.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux:
  btrfs: minimal conversion to errseq_t writeback error reporting on fsync
  xfs: minimal conversion to errseq_t writeback error reporting
  ext4: use errseq_t based error handling for reporting data writeback errors
  fs: convert __generic_file_fsync to use errseq_t based reporting
  block: convert to errseq_t based writeback error tracking
  dax: set errors in mapping when writeback fails
  Documentation: flesh out the section in vfs.txt on storing and reporting writeback errors
  mm: set both AS_EIO/AS_ENOSPC and errseq_t in mapping_set_error
  fs: new infrastructure for writeback error handling and reporting
  lib: add errseq_t type and infrastructure for handling it
  mm: don't TestClearPageError in __filemap_fdatawait_range
  mm: clear AS_EIO/AS_ENOSPC when writeback initiation fails
  jbd2: don't clear and reset errors after waiting on writeback
  buffer: set errors in mapping at the time that the error occurs
  fs: check for writeback errors after syncing out buffers in generic_file_fsync
  buffer: use mapping_set_error instead of setting the flag
  mm: fix mapping_set_error call in me_pagecache_dirty
2017-07-07 19:38:17 -07:00
Linus Torvalds
33198c165b Writeback error handling fixes (pile #1)
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Merge tag 'for-linus-v4.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux

Pull Writeback error handling fixes from Jeff Layton:
 "The main rationale for all of these changes is to tighten up writeback
  error reporting to userland. There are many ways now that writeback
  errors can be lost, such that fsync/fdatasync/msync return 0 when
  writeback actually failed.

  This pile contains a small set of cleanups and writeback error
  handling fixes that I was able to break off from the main pile (#2).

  Two of the patches in this pile are trivial. The exceptions are the
  patch to fix up error handling in write_one_page, and the patch to
  make JFS pay attention to write_one_page errors"

* tag 'for-linus-v4.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux:
  fs: remove call_fsync helper function
  mm: clean up error handling in write_one_page
  JFS: do not ignore return code from write_one_page()
  mm: drop "wait" parameter from write_one_page()
2017-07-07 18:39:15 -07:00
Linus Torvalds
d691b7e7d1 powerpc updates for 4.13
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
  ...
2017-07-07 13:55:45 -07:00
Michal Hocko
4932381ee2 mm, memory_hotplug: move movable_node to the hotplug proper
movable_node_is_enabled is defined in memblock proper while it is
initialized from the memory hotplug proper.  This is quite messy and it
makes a dependency between the two so move movable_node along with the
helper functions to memory_hotplug.

To make it more entertaining the kernel parameter is ignored unless
CONFIG_HAVE_MEMBLOCK_NODE_MAP=y because we do not have the node
information for each memblock otherwise.  So let's warn when the option
is disabled.

Link: http://lkml.kernel.org/r/20170529114141.536-4-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>
2017-07-06 16:24:35 -07:00
Michal Hocko
f70029bbaa mm, memory_hotplug: drop CONFIG_MOVABLE_NODE
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>
2017-07-06 16:24:35 -07:00
Michal Hocko
57c0a17238 mm, memory_hotplug: drop artificial restriction on online/offline
Patch series "remove CONFIG_MOVABLE_NODE".

I am continuing to clean up the memory hotplug code and
CONFIG_MOVABLE_NODE seems dubious at best.  The following two patches
simply removes the flag and make it de-facto always enabled.

The current semantic of the config option is twofold 1) it automatically
binds hotplugable nodes to have memory in zone_movable by default when
movable_node is enabled 2) forbids memory hotplug to online all the
memory as movable when !CONFIG_MOVABLE_NODE.

The later restriction is quite dubious because there is no clear cut of
how much normal memory do we need for a reasonable system operation.  A
single memory block which is sufficient to allow further movable onlines
is far from sufficient (e.g a node with >2GB and memblocks 128MB will
fill up this zone with struct pages leaving nothing for other
allocations).  Removing the config option will not only reduce the
configuration space it also removes quite some code.

The semantic of the movable_node command line parameter is preserved.

The first patch removes the restriction mentioned above and the second
one simply removes all the CONFIG_MOVABLE_NODE related stuff.  The last
patch moves movable_node flag handling to memory_hotplug proper where it
belongs.

[1] http://lkml.kernel.org/r/20170524122411.25212-1-mhocko@kernel.org

This patch (of 3):

Commit 74d42d8fe1 ("memory_hotplug: ensure every online node has
NORMAL memory") has introduced a restriction that every numa node has to
have at least some memory in !movable zones before a first movable
memory can be onlined if !CONFIG_MOVABLE_NODE.

Likewise can_offline_normal checks the amount of normal memory in
!movable zones and it disallows to offline memory if there is no normal
memory left with a justification that "memory-management acts bad when
we have nodes which is online but don't have any normal memory".

While it is true that not having _any_ memory for kernel allocations on
a NUMA node is far from great and such a node would be quite subotimal
because all kernel allocations will have to fallback to another NUMA
node but there is no reason to disallow such a configuration in
principle.

Besides that there is not really a big difference to have one memblock
for ZONE_NORMAL available or none.  With 128MB size memblocks the system
might trash on the kernel allocations requests anyway.  It is really
hard to draw a line on how much normal memory is really sufficient so we
have to rely on administrator to configure system sanely therefore drop
the artificial restriction and remove can_offline_normal and
can_online_high_movable altogether.

Link: http://lkml.kernel.org/r/20170529114141.536-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Reza Arbab <arbab@linux.vnet.ibm.com>
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>
2017-07-06 16:24:35 -07:00
Johannes Weiner
7779f21236 mm: memcontrol: account slab stats per lruvec
Josef's redesign of the balancing between slab caches and the page cache
requires slab cache statistics at the lruvec level.

Link: http://lkml.kernel.org/r/20170530181724.27197-7-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Michal Hocko <mhocko@suse.com>
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>
2017-07-06 16:24:35 -07:00
Johannes Weiner
00f3ca2c2d mm: memcontrol: per-lruvec stats infrastructure
lruvecs are at the intersection of the NUMA node and memcg, which is the
scope for most paging activity.

Introduce a convenient accounting infrastructure that maintains
statistics per node, per memcg, and the lruvec itself.

Then convert over accounting sites for statistics that are already
tracked in both nodes and memcgs and can be easily switched.

[hannes@cmpxchg.org: fix crash in the new cgroup stat keeping code]
  Link: http://lkml.kernel.org/r/20170531171450.GA10481@cmpxchg.org
[hannes@cmpxchg.org: don't track uncharged pages at all
  Link: http://lkml.kernel.org/r/20170605175254.GA8547@cmpxchg.org
[hannes@cmpxchg.org: add missing free_percpu()]
  Link: http://lkml.kernel.org/r/20170605175354.GB8547@cmpxchg.org
[linux@roeck-us.net: hexagon: fix build error caused by include file order]
  Link: http://lkml.kernel.org/r/20170617153721.GA4382@roeck-us.net
Link: http://lkml.kernel.org/r/20170530181724.27197-6-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Michal Hocko <mhocko@suse.com>
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>
2017-07-06 16:24:35 -07:00
Johannes Weiner
ed52be7bfd mm: memcontrol: use generic mod_memcg_page_state for kmem pages
The kmem-specific functions do the same thing.  Switch and drop.

Link: http://lkml.kernel.org/r/20170530181724.27197-5-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Michal Hocko <mhocko@suse.com>
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>
2017-07-06 16:24:35 -07:00
Johannes Weiner
320492961c mm: memcontrol: use the node-native slab memory counters
Now that the slab counters are moved from the zone to the node level we
can drop the private memcg node stats and use the official ones.

Link: http://lkml.kernel.org/r/20170530181724.27197-4-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Michal Hocko <mhocko@suse.com>
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>
2017-07-06 16:24:35 -07:00
Johannes Weiner
385386cff4 mm: vmstat: move slab statistics from zone to node counters
Patch series "mm: per-lruvec slab stats"

Josef is working on a new approach to balancing slab caches and the page
cache.  For this to work, he needs slab cache statistics on the lruvec
level.  These patches implement that by adding infrastructure that
allows updating and reading generic VM stat items per lruvec, then
switches some existing VM accounting sites, including the slab
accounting ones, to this new cgroup-aware API.

I'll follow up with more patches on this, because there is actually
substantial simplification that can be done to the memory controller
when we replace private memcg accounting with making the existing VM
accounting sites cgroup-aware.  But this is enough for Josef to base his
slab reclaim work on, so here goes.

This patch (of 5):

To re-implement slab cache vs.  page cache balancing, we'll need the
slab counters at the lruvec level, which, ever since lru reclaim was
moved from the zone to the node, is the intersection of the node, not
the zone, and the memcg.

We could retain the per-zone counters for when the page allocator dumps
its memory information on failures, and have counters on both levels -
which on all but NUMA node 0 is usually redundant.  But let's keep it
simple for now and just move them.  If anybody complains we can restore
the per-zone counters.

[hannes@cmpxchg.org: fix oops]
  Link: http://lkml.kernel.org/r/20170605183511.GA8915@cmpxchg.org
Link: http://lkml.kernel.org/r/20170530181724.27197-3-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
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>
2017-07-06 16:24:35 -07:00
Markus Elfring
2b2695f5fd mm/zswap.c: delete an error message for a failed memory allocation in zswap_dstmem_prepare()
Omit an extra message for a memory allocation failure in this function.

This issue was detected by using the Coccinelle software.

Link: http://events.linuxfoundation.org/sites/events/files/slides/LCJ16-Refactor_Strings-WSang_0.pdf
Link: http://lkml.kernel.org/r/bae25b04-2ce2-7137-a71c-50d7b4f06431@users.sourceforge.net
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Seth Jennings <sjenning@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:35 -07:00
Markus Elfring
9cd1f701ce mm/zswap.c: improve a size determination in zswap_frontswap_init()
Replace the specification of a data structure by a pointer dereference
as the parameter for the operator "sizeof" to make the corresponding
size determination a bit safer according to the Linux coding style
convention.

Link: http://lkml.kernel.org/r/19f9da22-092b-f867-bdf6-f4dbad7ccf1f@users.sourceforge.net
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Seth Jennings <sjenning@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:35 -07:00
Markus Elfring
f4ae0ce0fd mm/zswap.c: delete an error message for a failed memory allocation in zswap_pool_create()
Omit an extra message for a memory allocation failure in this function.

This issue was detected by using the Coccinelle software.

Link: http://events.linuxfoundation.org/sites/events/files/slides/LCJ16-Refactor_Strings-WSang_0.pdf
Link: http://lkml.kernel.org/r/2345aabc-ae98-1d31-afba-40a02c5baf3d@users.sourceforge.net
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Seth Jennings <sjenning@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:35 -07:00
Huang Ying
155b5f88e7 mm/swapfile.c: sort swap entries before free
To reduce the lock contention of swap_info_struct->lock when freeing
swap entry.  The freed swap entries will be collected in a per-CPU
buffer firstly, and be really freed later in batch.  During the batch
freeing, if the consecutive swap entries in the per-CPU buffer belongs
to same swap device, the swap_info_struct->lock needs to be
acquired/released only once, so that the lock contention could be
reduced greatly.  But if there are multiple swap devices, it is possible
that the lock may be unnecessarily released/acquired because the swap
entries belong to the same swap device are non-consecutive in the
per-CPU buffer.

To solve the issue, the per-CPU buffer is sorted according to the swap
device before freeing the swap entries.

With the patch, the memory (some swapped out) free time reduced 11.6%
(from 2.65s to 2.35s) in the vm-scalability swap-w-rand test case with
16 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
swapping, the test case creates 16 processes, which allocate and write
to the anonymous pages until the RAM and part of the swap device is used
up, finally the memory (some swapped out) is freed before exit.

[akpm@linux-foundation.org: tweak comment]
Link: http://lkml.kernel.org/r/20170525005916.25249-1-ying.huang@intel.com
Signed-off-by: Huang Ying <ying.huang@intel.com>
Acked-by: Tim Chen <tim.c.chen@intel.com>
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>
2017-07-06 16:24:35 -07:00
Konstantin Khlebnikov
8e675f7af5 mm/oom_kill: count global and memory cgroup oom kills
Show count of oom killer invocations in /proc/vmstat and count of
processes killed in memory cgroup in knob "memory.events" (in
memory.oom_control for v1 cgroup).

Also describe difference between "oom" and "oom_kill" in memory cgroup
documentation.  Currently oom in memory cgroup kills tasks iff shortage
has happened inside page fault.

These counters helps in monitoring oom kills - for now the only way is
grepping for magic words in kernel log.

[akpm@linux-foundation.org: fix for mem_cgroup_count_vm_event() rename]
[akpm@linux-foundation.org: fix comment, per Konstantin]
Link: http://lkml.kernel.org/r/149570810989.203600.9492483715840752937.stgit@buzz
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Roman Guschin <guroan@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:35 -07:00
Roman Gushchin
2262185c5b mm: per-cgroup memory reclaim stats
Track the following reclaim counters for every memory cgroup: PGREFILL,
PGSCAN, PGSTEAL, PGACTIVATE, PGDEACTIVATE, PGLAZYFREE and PGLAZYFREED.

These values are exposed using the memory.stats interface of cgroup v2.

The meaning of each value is the same as for global counters, available
using /proc/vmstat.

Also, for consistency, rename mem_cgroup_count_vm_event() to
count_memcg_event_mm().

Link: http://lkml.kernel.org/r/1494530183-30808-1-git-send-email-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Suggested-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vladimir Davydov <vdavydov.dev@gmail.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:35 -07:00
Catalin Marinas
94f4a1618b mm: kmemleak: treat vm_struct as alternative reference to vmalloc'ed objects
Kmemleak requires that vmalloc'ed objects have a minimum reference count
of 2: one in the corresponding vm_struct object and the other owned by
the vmalloc() caller.  There are cases, however, where the original
vmalloc() returned pointer is lost and, instead, a pointer to vm_struct
is stored (see free_thread_stack()).  Kmemleak currently reports such
objects as leaks.

This patch adds support for treating any surplus references to an object
as additional references to a specified object.  It introduces the
kmemleak_vmalloc() API function which takes a vm_struct pointer and sets
its surplus reference passing to the actual vmalloc() returned pointer.
The __vmalloc_node_range() calling site has been modified accordingly.

Link: http://lkml.kernel.org/r/1495726937-23557-4-git-send-email-catalin.marinas@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: "Luis R. Rodriguez" <mcgrof@kernel.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: "Luis R. Rodriguez" <mcgrof@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:34 -07:00
Catalin Marinas
04f70d13ca mm: kmemleak: factor object reference updating out of scan_block()
scan_block() updates the number of references (pointers) to objects,
adding them to the gray_list when object->min_count is reached.  The
patch factors out this functionality into a separate update_refs()
function.

Link: http://lkml.kernel.org/r/1495726937-23557-3-git-send-email-catalin.marinas@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: "Luis R. Rodriguez" <mcgrof@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:34 -07:00
Catalin Marinas
f66abf09e0 mm: kmemleak: slightly reduce the size of some structures on 64-bit architectures
Change the kmemleak_object.flags type to unsigned int and moves the
early_log.min_count (int) near early_log.op_type (int) to slightly
reduce the size of these structures on 64-bit architectures.

Link: http://lkml.kernel.org/r/1495726937-23557-2-git-send-email-catalin.marinas@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: "Luis R. Rodriguez" <mcgrof@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:34 -07:00
Vlastimil Babka
e0dd7d53a6 mm, mempolicy: don't check cpuset seqlock where it doesn't matter
Two wrappers of __alloc_pages_nodemask() are checking
task->mems_allowed_seq themselves to retry allocation that has raced
with a cpuset update.

This has been shown to be ineffective in preventing premature OOM's
which can happen in __alloc_pages_slowpath() long before it returns back
to the wrappers to detect the race at that level.

Previous patches have made __alloc_pages_slowpath() more robust, so we
can now simply remove the seqlock checking in the wrappers to prevent
further wrong impression that it can actually help.

Link: http://lkml.kernel.org/r/20170517081140.30654-7-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dimitri Sivanich <sivanich@sgi.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:34 -07:00
Vlastimil Babka
213980c0f2 mm, mempolicy: simplify rebinding mempolicies when updating cpusets
Commit c0ff7453bb ("cpuset,mm: fix no node to alloc memory when
changing cpuset's mems") has introduced a two-step protocol when
rebinding task's mempolicy due to cpuset update, in order to avoid a
parallel allocation seeing an empty effective nodemask and failing.

Later, commit cc9a6c8776 ("cpuset: mm: reduce large amounts of memory
barrier related damage v3") introduced a seqlock protection and removed
the synchronization point between the two update steps.  At that point
(or perhaps later), the two-step rebinding became unnecessary.

Currently it only makes sure that the update first adds new nodes in
step 1 and then removes nodes in step 2.  Without memory barriers the
effects are questionable, and even then this cannot prevent a parallel
zonelist iteration checking the nodemask at each step to observe all
nodes as unusable for allocation.  We now fully rely on the seqlock to
prevent premature OOMs and allocation failures.

We can thus remove the two-step update parts and simplify the code.

Link: http://lkml.kernel.org/r/20170517081140.30654-5-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dimitri Sivanich <sivanich@sgi.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:34 -07:00
Vlastimil Babka
04ec6264f2 mm, page_alloc: pass preferred nid instead of zonelist to allocator
The main allocator function __alloc_pages_nodemask() takes a zonelist
pointer as one of its parameters.  All of its callers directly or
indirectly obtain the zonelist via node_zonelist() using a preferred
node id and gfp_mask.  We can make the code a bit simpler by doing the
zonelist lookup in __alloc_pages_nodemask(), passing it a preferred node
id instead (gfp_mask is already another parameter).

There are some code size benefits thanks to removal of inlined
node_zonelist():

  bloat-o-meter add/remove: 2/2 grow/shrink: 4/36 up/down: 399/-1351 (-952)

This will also make things simpler if we proceed with converting cpusets
to zonelists.

Link: http://lkml.kernel.org/r/20170517081140.30654-4-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Christoph Lameter <cl@linux.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Dimitri Sivanich <sivanich@sgi.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:34 -07:00
Vlastimil Babka
45816682b2 mm, mempolicy: stop adjusting current->il_next in mpol_rebind_nodemask()
The task->il_next variable stores the next allocation node id for task's
MPOL_INTERLEAVE policy.  mpol_rebind_nodemask() updates interleave and
bind mempolicies due to changing cpuset mems.  Currently it also tries
to make sure that current->il_next is valid within the updated nodemask.
This is bogus, because 1) we are updating potentially any task's
mempolicy, not just current, and 2) we might be updating a per-vma
mempolicy, not task one.

The interleave_nodes() function that uses il_next can cope fine with the
value not being within the currently allowed nodes, so this hasn't
manifested as an actual issue.

We can remove the need for updating il_next completely by changing it to
il_prev and store the node id of the previous interleave allocation
instead of the next id.  Then interleave_nodes() can calculate the next
id using the current nodemask and also store it as il_prev, except when
querying the next node via do_get_mempolicy().

Link: http://lkml.kernel.org/r/20170517081140.30654-3-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Christoph Lameter <cl@linux.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dimitri Sivanich <sivanich@sgi.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:34 -07:00
Vlastimil Babka
902b62810a mm, page_alloc: fix more premature OOM due to race with cpuset update
I would like to stress that this patchset aims to fix issues and cleanup
the code *within the existing documented semantics*, i.e.  patch 1
ignores mempolicy restrictions if the set of allowed nodes has no
intersection with set of nodes allowed by cpuset.  I believe discussing
potential changes of the semantics can be better done once we have a
baseline with no known bugs of the current semantics.

I've recently summarized the cpuset/mempolicy issues in a LSF/MM
proposal [1] and the discussion itself [2].  I've been trying to rewrite
the handling as proposed, with the idea that changing semantics to make
all mempolicies static wrt cpuset updates (and discarding the relative
and default modes) can be tried on top, as there's a high risk of being
rejected/reverted because somebody might still care about the removed
modes.

However I haven't yet figured out how to properly:

1) make mempolicies swappable instead of rebinding in place. I thought
   mbind() already works that way and uses refcounting to avoid
   use-after-free of the old policy by a parallel allocation, but turns
   out true refcounting is only done for shared (shmem) mempolicies, and
   the actual protection for mbind() comes from mmap_sem. Extending the
   refcounting means more overhead in allocator hot path. Also swapping
   whole mempolicies means that we have to allocate the new ones, which
   can fail, and reverting of the partially done work also means
   allocating (note that mbind() doesn't care and will just leave part
   of the range updated and part not updated when returning -ENOMEM...).

2) make cpuset's task->mems_allowed also swappable (after converting it
   from nodemask to zonelist, which is the easy part) for mostly the
   same reasons.

The good news is that while trying to do the above, I've at least
figured out how to hopefully close the remaining premature OOM's, and do
a buch of cleanups on top, removing quite some of the code that was also
supposed to prevent the cpuset update races, but doesn't work anymore
nowadays.  This should fix the most pressing concerns with this topic
and give us a better baseline before either proceeding with the original
proposal, or pushing a change of semantics that removes the problem 1)
above.  I'd be then fine with trying to change the semantic first and
rewrite later.

Patchset has been tested with the LTP cpuset01 stress test.

[1] https://lkml.kernel.org/r/4c44a589-5fd8-08d0-892c-e893bb525b71@suse.cz
[2] https://lwn.net/Articles/717797/
[3] https://marc.info/?l=linux-mm&m=149191957922828&w=2

This patch (of 6):

Commit e47483bca2 ("mm, page_alloc: fix premature OOM when racing with
cpuset mems update") has fixed known recent regressions found by LTP's
cpuset01 testcase.  I have however found that by modifying the testcase
to use per-vma mempolicies via bind(2) instead of per-task mempolicies
via set_mempolicy(2), the premature OOM still happens and the issue is
much older.

The root of the problem is that the cpuset's mems_allowed and
mempolicy's nodemask can temporarily have no intersection, thus
get_page_from_freelist() cannot find any usable zone.  The current
semantic for empty intersection is to ignore mempolicy's nodemask and
honour cpuset restrictions.  This is checked in node_zonelist(), but the
racy update can happen after we already passed the check.  Such races
should be protected by the seqlock task->mems_allowed_seq, but it
doesn't work here, because 1) mpol_rebind_mm() does not happen under
seqlock for write, and doing so would lead to deadlock, as it takes
mmap_sem for write, while the allocation can have mmap_sem for read when
it's taking the seqlock for read.  And 2) the seqlock cookie of callers
of node_zonelist() (alloc_pages_vma() and alloc_pages_current()) is
different than the one of __alloc_pages_slowpath(), so there's still a
potential race window.

This patch fixes the issue by having __alloc_pages_slowpath() check for
empty intersection of cpuset and ac->nodemask before OOM or allocation
failure.  If it's indeed empty, the nodemask is ignored and allocation
retried, which mimics node_zonelist().  This works fine, because almost
all callers of __alloc_pages_nodemask are obtaining the nodemask via
node_zonelist().  The only exception is new_node_page() from hotplug,
where the potential violation of nodemask isn't an issue, as there's
already a fallback allocation attempt without any nodemask.  If there's
a future caller that needs to have its specific nodemask honoured over
task's cpuset restrictions, we'll have to e.g.  add a gfp flag for that.

Link: http://lkml.kernel.org/r/20170517081140.30654-2-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: David Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Dimitri Sivanich <sivanich@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:34 -07:00
Punit Agrawal
5fd27b8e7d mm: rmap: use correct helper when poisoning hugepages
Using set_pte_at() does not do the right thing when putting down
HWPOISON swap entries for hugepages on architectures that support
contiguous ptes.

Fix this problem by using set_huge_swap_pte_at() which was introduced to
fix exactly this problem.

Link: http://lkml.kernel.org/r/20170522133604.11392-7-punit.agrawal@arm.com
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Acked-by: Steve Capper <steve.capper@arm.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:34 -07:00
Punit Agrawal
e5251fd430 mm/hugetlb: introduce set_huge_swap_pte_at() helper
set_huge_pte_at(), an architecture callback to populate hugepage ptes,
does not provide the range of virtual memory that is targeted.  This
leads to ambiguity when dealing with swap entries on architectures that
support hugepages consisting of contiguous ptes.

Fix the problem by introducing an overridable helper that is called when
populating the page tables with swap entries.  The size of the targeted
region is provided to the helper to help determine the number of entries
to be updated.

Provide a default implementation that maintains the current behaviour.

[punit.agrawal@arm.com: v4]
  Link: http://lkml.kernel.org/r/20170524115409.31309-8-punit.agrawal@arm.com
[punit.agrawal@arm.com: add an empty definition for set_huge_swap_pte_at()]
  Link: http://lkml.kernel.org/r/20170525171331.31469-1-punit.agrawal@arm.com
Link: http://lkml.kernel.org/r/20170522133604.11392-6-punit.agrawal@arm.com
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Acked-by: Steve Capper <steve.capper@arm.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:34 -07:00
Punit Agrawal
9386fac34c mm/hugetlb: allow architectures to override huge_pte_clear()
When unmapping a hugepage range, huge_pte_clear() is used to clear the
page table entries that are marked as not present.  huge_pte_clear()
internally just ends up calling pte_clear() which does not correctly
deal with hugepages consisting of contiguous page table entries.

Add a size argument to address this issue and allow architectures to
override huge_pte_clear() by wrapping it in a #ifndef block.

Update s390 implementation with the size parameter as well.

Note that the change only affects huge_pte_clear() - the other generic
hugetlb functions don't need any change.

Link: http://lkml.kernel.org/r/20170522162555.4313-1-punit.agrawal@arm.com
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>	[s390 bits]
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Steve Capper <steve.capper@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:34 -07:00
Punit Agrawal
7868a2087e mm/hugetlb: add size parameter to huge_pte_offset()
A poisoned or migrated hugepage is stored as a swap entry in the page
tables.  On architectures that support hugepages consisting of
contiguous page table entries (such as on arm64) this leads to ambiguity
in determining the page table entry to return in huge_pte_offset() when
a poisoned entry is encountered.

Let's remove the ambiguity by adding a size parameter to convey
additional information about the requested address.  Also fixup the
definition/usage of huge_pte_offset() throughout the tree.

Link: http://lkml.kernel.org/r/20170522133604.11392-4-punit.agrawal@arm.com
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Acked-by: Steve Capper <steve.capper@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: James Hogan <james.hogan@imgtec.com> (odd fixer:METAG ARCHITECTURE)
Cc: Ralf Baechle <ralf@linux-mips.org> (supporter:MIPS)
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
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: "David S. Miller" <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:34 -07:00
Punit Agrawal
d63206ee32 mm, gup: ensure real head page is ref-counted when using hugepages
When speculatively taking references to a hugepage using
page_cache_add_speculative() in gup_huge_pmd(), it is assumed that the
page returned by pmd_page() is the head page.  Although normally true,
this assumption doesn't hold when the hugepage comprises of successive
page table entries such as when using contiguous bit on arm64 at PTE or
PMD levels.

This can be addressed by ensuring that the page passed to
page_cache_add_speculative() is the real head or by de-referencing the
head page within the function.

We take the first approach to keep the usage pattern aligned with
page_cache_get_speculative() where users already pass the appropriate
page, i.e., the de-referenced head.

Apply the same logic to fix gup_huge_[pud|pgd]() as well.

[punit.agrawal@arm.com: fix arm64 ltp failure]
  Link: http://lkml.kernel.org/r/20170619170145.25577-5-punit.agrawal@arm.com
Link: http://lkml.kernel.org/r/20170522133604.11392-3-punit.agrawal@arm.com
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Acked-by: Steve Capper <steve.capper@arm.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Mark Rutland <mark.rutland@arm.com>
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>
2017-07-06 16:24:34 -07:00
Will Deacon
a3e328556d mm, gup: remove broken VM_BUG_ON_PAGE compound check for hugepages
When operating on hugepages with DEBUG_VM enabled, the GUP code checks
the compound head for each tail page prior to calling
page_cache_add_speculative.  This is broken, because on the fast-GUP
path (where we don't hold any page table locks) we can be racing with a
concurrent invocation of split_huge_page_to_list.

split_huge_page_to_list deals with this race by using page_ref_freeze to
freeze the page and force concurrent GUPs to fail whilst the component
pages are modified.  This modification includes clearing the
compound_head field for the tail pages, so checking this prior to a
successful call to page_cache_add_speculative can lead to false
positives: In fact, page_cache_add_speculative *already* has this check
once the page refcount has been successfully updated, so we can simply
remove the broken calls to VM_BUG_ON_PAGE.

Link: http://lkml.kernel.org/r/20170522133604.11392-2-punit.agrawal@arm.com
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Acked-by: Steve Capper <steve.capper@arm.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Michal Hocko <mhocko@suse.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>
2017-07-06 16:24:34 -07:00
Naoya Horiguchi
8bc3c3fe4f mm: drop NULL return check of pte_offset_map_lock()
pte_offset_map_lock() finds and takes ptl, and returns pte.  But some
callers return without unlocking the ptl when pte == NULL, which seems
weird.

Git history said that !pte check in change_pte_range() was introduced in
commit 1ad9f620c3 ("mm: numa: recheck for transhuge pages under lock
during protection changes") and still remains after commit 175ad4f1e7
("mm: mprotect: use pmd_trans_unstable instead of taking the pmd_lock")
which partially reverts 1ad9f620c3.  So I think that it's just dead
code.

Many other caller of pte_offset_map_lock() never check NULL return, so
let's do likewise.

Link: http://lkml.kernel.org/r/1495089737-1292-1-git-send-email-n-horiguchi@ah.jp.nec.com
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
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>
2017-07-06 16:24:33 -07:00
Matthias Kaehlcke
d73d3c9f69 mm/page_alloc.c: mark bad_range() and meminit_pfn_in_nid() as __maybe_unused
The functions are not used in some configurations.  Adding the attribute
fixes the following warnings when building with clang:

  mm/page_alloc.c:409:19: error: function 'bad_range' is not needed and
      will not be emitted [-Werror,-Wunneeded-internal-declaration]

  mm/page_alloc.c:1106:30: error: unused function 'meminit_pfn_in_nid'
      [-Werror,-Wunused-function]

Link: http://lkml.kernel.org/r/20170518182030.165633-1-mka@chromium.org
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:33 -07:00
Aneesh Kumar K.V
e1073d1e79 mm/hugetlb: clean up ARCH_HAS_GIGANTIC_PAGE
This moves the #ifdef in C code to a Kconfig dependency.  Also we move
the gigantic_page_supported() function to be arch specific.

This allows architectures to conditionally enable runtime allocation of
gigantic huge page.  Architectures like ppc64 supports different
gigantic huge page size (16G and 1G) based on the translation mode
selected.  This provides an opportunity for ppc64 to enable runtime
allocation only w.r.t 1G hugepage.

No functional change in this patch.

Link: http://lkml.kernel.org/r/1494995292-4443-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:33 -07:00
Pavel Tatashin
9017217b6f mm: adaptive hash table scaling
Allow hash tables to scale with memory but at slower pace, when
HASH_ADAPT is provided every time memory quadruples the sizes of hash
tables will only double instead of quadrupling as well.  This algorithm
starts working only when memory size reaches a certain point, currently
set to 64G.

This is example of dentry hash table size, before and after four various
memory configurations:

MEMORY	   SCALE	 HASH_SIZE
	old	new	old	new
    8G	 13	 13      8M      8M
   16G	 13	 13     16M     16M
   32G	 13	 13     32M     32M
   64G	 13	 13     64M     64M
  128G	 13	 14    128M     64M
  256G	 13	 14    256M    128M
  512G	 13	 15    512M    128M
 1024G	 13	 15   1024M    256M
 2048G	 13	 16   2048M    256M
 4096G	 13	 16   4096M    512M
 8192G	 13	 17   8192M    512M
16384G	 13	 17  16384M   1024M
32768G	 13	 18  32768M   1024M
65536G	 13	 18  65536M   2048M

The effect of this change on runtime is undetectable as filesystem
growth is not proportional to machine memory size as is currently
assumed.  The change effects only large memory machine.  Additional
tuning might be needed, but that can be done by the clients of the
kmem_cache_create interface, not the generic cache allocator itself.

The adaptive hashing is disabled on 32 bit systems to avoid confusion of
whether base should be different for smaller systems, and to avoid
overflows.

[mhocko@suse.com: drop HASH_ADAPT]
  Link: http://lkml.kernel.org/r/20170509094607.GG6481@dhcp22.suse.cz
[pasha.tatashin@oracle.com: UL -> ULL fix]
  Link: http://lkml.kernel.org/r/1495300013-653283-2-git-send-email-pasha.tatashin@oracle.com
[pasha.tatashin@oracle.com: disable adaptive hash on 32 bit systems]
  Link: http://lkml.kernel.org/r/1495469329-755807-2-git-send-email-pasha.tatashin@oracle.com
Link: http://lkml.kernel.org/r/1488432825-92126-5-git-send-email-pasha.tatashin@oracle.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: David Miller <davem@davemloft.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Babu Moger <babu.moger@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:33 -07:00
Pavel Tatashin
3749a8f008 mm: zero hash tables in allocator
Add a new flag HASH_ZERO which when provided grantees that the hash
table that is returned by alloc_large_system_hash() is zeroed.  In most
cases that is what is needed by the caller.  Use page level allocator's
__GFP_ZERO flags to zero the memory.  It is using memset() which is
efficient method to zero memory and is optimized for most platforms.

Link: http://lkml.kernel.org/r/1488432825-92126-3-git-send-email-pasha.tatashin@oracle.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Babu Moger <babu.moger@oracle.com>
Cc: David Miller <davem@davemloft.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:33 -07:00
Aneesh Kumar K.V
4dc71451a2 mm/follow_page_mask: add support for hugepage directory entry
Architectures like ppc64 supports hugepage size that is not mapped to
any of of the page table levels.  Instead they add an alternate page
table entry format called hugepage directory (hugepd).  hugepd indicates
that the page table entry maps to a set of hugetlb pages.  Add support
for this in generic follow_page_mask code.  We already support this
format in the generic gup code.

The default implementation prints warning and returns NULL.  We will add
ppc64 support in later patches

Link: http://lkml.kernel.org/r/1494926612-23928-7-git-send-email-aneesh.kumar@linux.vnet.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Mike Kravetz <kravetz@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:33 -07:00
Anshuman Khandual
faaa5b62d3 mm/follow_page_mask: add support for hugetlb pgd entries
ppc64 supports pgd hugetlb entries.  Add code to handle hugetlb pgd
entries to follow_page_mask so that ppc64 can switch to it to handle
hugetlbe entries.

Link: http://lkml.kernel.org/r/1494926612-23928-5-git-send-email-aneesh.kumar@linux.vnet.ibm.com
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Mike Kravetz <kravetz@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:33 -07:00
Aneesh Kumar K.V
d5ed7444da mm/hugetlb: export hugetlb_entry_migration helper
We will be using this later from the ppc64 code.  Change the return type
to bool.

Link: http://lkml.kernel.org/r/1494926612-23928-4-git-send-email-aneesh.kumar@linux.vnet.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Mike Kravetz <kravetz@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:33 -07:00
Aneesh Kumar K.V
080dbb618b mm/follow_page_mask: split follow_page_mask to smaller functions.
Makes code reading easy.  No functional changes in this patch.  In a
followup patch, we will be updating the follow_page_mask to handle
hugetlb hugepd format so that archs like ppc64 can switch to the generic
version.  This split helps in doing that nicely.

Link: http://lkml.kernel.org/r/1494926612-23928-3-git-send-email-aneesh.kumar@linux.vnet.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Mike Kravetz <kravetz@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:33 -07:00
Aneesh Kumar K.V
383321ab85 mm/hugetlb/migration: use set_huge_pte_at instead of set_pte_at
Patch series "HugeTLB migration support for PPC64", v2.

This patch (of 9):

The right interface to use to set a hugetlb pte entry is set_huge_pte_at.
Use that instead of set_pte_at.

Link: http://lkml.kernel.org/r/1494926612-23928-2-git-send-email-aneesh.kumar@linux.vnet.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Mike Kravetz <kravetz@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:33 -07:00
Anshuman Khandual
94310cbcaa mm/madvise: enable (soft|hard) offline of HugeTLB pages at PGD level
Though migrating gigantic HugeTLB pages does not sound much like real
world use case, they can be affected by memory errors.  Hence migration
at the PGD level HugeTLB pages should be supported just to enable soft
and hard offline use cases.

While allocating the new gigantic HugeTLB page, it should not matter
whether new page comes from the same node or not.  There would be very
few gigantic pages on the system afterall, we should not be bothered
about node locality when trying to save a big page from crashing.

This change renames dequeu_huge_page_node() function as dequeue_huge
_page_node_exact() preserving it's original functionality.  Now the new
dequeue_huge_page_node() function scans through all available online nodes
to allocate a huge page for the NUMA_NO_NODE case and just falls back
calling dequeu_huge_page_node_exact() for all other cases.

[arnd@arndb.de: make hstate_is_gigantic() inline]
  Link: http://lkml.kernel.org/r/20170522124748.3911296-1-arnd@arndb.de
Link: http://lkml.kernel.org/r/20170516100509.20122-1-khandual@linux.vnet.ibm.com
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: 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>
2017-07-06 16:24:33 -07:00
Michal Hocko
559bfc7d1b mm, memory_hotplug: remove unused cruft after memory hotplug rework
zone_for_memory doesn't have any user anymore as well as the whole zone
shifting infrastructure so drop them all.

This shouldn't introduce any functional changes.

Link: http://lkml.kernel.org/r/20170515085827.16474-15-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Daniel Kiper <daniel.kiper@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Tobias Regnery <tobias.regnery@gmail.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:32 -07:00
Michal Hocko
cdf72f2504 mm, memory_hotplug: fix the section mismatch warning
Tobias has reported following section mismatches introduced by "mm,
memory_hotplug: do not associate hotadded memory to zones until online".

  WARNING: mm/built-in.o(.text+0x5a1c2): Section mismatch in reference from the function move_pfn_range_to_zone() to the function .meminit.text:memmap_init_zone()
  The function move_pfn_range_to_zone() references
  the function __meminit memmap_init_zone().
  This is often because move_pfn_range_to_zone lacks a __meminit
  annotation or the annotation of memmap_init_zone is wrong.

  WARNING: mm/built-in.o(.text+0x5a25b): Section mismatch in reference from the function move_pfn_range_to_zone() to the function .meminit.text:init_currently_empty_zone()
  The function move_pfn_range_to_zone() references
  the function __meminit init_currently_empty_zone().
  This is often because move_pfn_range_to_zone lacks a __meminit
  annotation or the annotation of init_currently_empty_zone is wrong.

  WARNING: vmlinux.o(.text+0x188aa2): Section mismatch in reference from the function move_pfn_range_to_zone() to the function .meminit.text:memmap_init_zone()
  The function move_pfn_range_to_zone() references
  the function __meminit memmap_init_zone().
  This is often because move_pfn_range_to_zone lacks a __meminit
  annotation or the annotation of memmap_init_zone is wrong.

  WARNING: vmlinux.o(.text+0x188b3b): Section mismatch in reference from the function move_pfn_range_to_zone() to the function .meminit.text:init_currently_empty_zone()
  The function move_pfn_range_to_zone() references
  the function __meminit init_currently_empty_zone().
  This is often because move_pfn_range_to_zone lacks a __meminit
  annotation or the annotation of init_currently_empty_zone is wrong.

Both memmap_init_zone and init_currently_empty_zone are marked __meminit
but move_pfn_range_to_zone is used outside of __meminit sections (e.g.
devm_memremap_pages) so we have to hide it from the checker by __ref
annotation.

Link: http://lkml.kernel.org/r/20170515085827.16474-14-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Tobias Regnery <tobias.regnery@gmail.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Daniel Kiper <daniel.kiper@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:32 -07:00
Michal Hocko
3d79a728f9 mm, memory_hotplug: replace for_device by want_memblock in arch_add_memory
arch_add_memory gets for_device argument which then controls whether we
want to create memblocks for created memory sections.  Simplify the
logic by telling whether we want memblocks directly rather than going
through pointless negation.  This also makes the api easier to
understand because it is clear what we want rather than nothing telling
for_device which can mean anything.

This shouldn't introduce any functional change.

Link: http://lkml.kernel.org/r/20170515085827.16474-13-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Daniel Kiper <daniel.kiper@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Tobias Regnery <tobias.regnery@gmail.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:32 -07:00
Michal Hocko
c246a213f5 mm, memory_hotplug: do not assume ZONE_NORMAL is default kernel zone
Heiko Carstens has noticed that he can generate overlapping zones for
ZONE_DMA and ZONE_NORMAL:

  DMA      [mem 0x0000000000000000-0x000000007fffffff]
  Normal   [mem 0x0000000080000000-0x000000017fffffff]

  $ cat /sys/devices/system/memory/block_size_bytes
  10000000
  $ cat /sys/devices/system/memory/memory5/valid_zones
  DMA
  $ echo 0 > /sys/devices/system/memory/memory5/online
  $ cat /sys/devices/system/memory/memory5/valid_zones
  Normal
  $ echo 1 > /sys/devices/system/memory/memory5/online
  Normal

  $ cat /proc/zoneinfo
  Node 0, zone      DMA
  spanned  524288        <-----
  present  458752
  managed  455078
  start_pfn:           0 <-----

  Node 0, zone   Normal
  spanned  720896
  present  589824
  managed  571648
  start_pfn:           327680 <-----

The reason is that we assume that the default zone for kernel onlining
is ZONE_NORMAL.  This was a simplification introduced by the memory
hotplug rework and it is easily fixable by checking the range overlap in
the zone order and considering the first matching zone as the default
one.  If there is no such zone then assume ZONE_NORMAL as we have been
doing so far.

Fixes: "mm, memory_hotplug: do not associate hotadded memory to zones until online"
Link: http://lkml.kernel.org/r/20170601083746.4924-3-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Tested-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Reza Arbab <arbab@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:32 -07:00
Michal Hocko
a69578a154 mm, memory_hotplug: fix MMOP_ONLINE_KEEP behavior
Heiko Carstens has noticed that the MMOP_ONLINE_KEEP is broken currently

  $ grep . memory3?/valid_zones
  memory34/valid_zones:Normal Movable
  memory35/valid_zones:Normal Movable
  memory36/valid_zones:Normal Movable
  memory37/valid_zones:Normal Movable

  $ echo online_movable > memory34/state
  $ grep . memory3?/valid_zones
  memory34/valid_zones:Movable
  memory35/valid_zones:Movable
  memory36/valid_zones:Movable
  memory37/valid_zones:Movable

  $ echo online > memory36/state
  $ grep . memory3?/valid_zones
  memory34/valid_zones:Movable
  memory36/valid_zones:Normal
  memory37/valid_zones:Movable

so we have effectively punched a hole into the movable zone.

The problem is that move_pfn_range() check for MMOP_ONLINE_KEEP is
wrong.  It only checks whether the given range is already part of the
movable zone which is not the case here as only memory34 is in the zone.
Fix this by using allow_online_pfn_range(..., MMOP_ONLINE_KERNEL) if
that is false then we can be sure that movable onlining is the right
thing to do.

Fixes: "mm, memory_hotplug: do not associate hotadded memory to zones until online"
Link: http://lkml.kernel.org/r/20170601083746.4924-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Tested-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Reza Arbab <arbab@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:32 -07:00
Michal Hocko
f1dd2cd13c mm, memory_hotplug: do not associate hotadded memory to zones until online
The current memory hotplug implementation relies on having all the
struct pages associate with a zone/node during the physical hotplug
phase (arch_add_memory->__add_pages->__add_section->__add_zone).  In the
vast majority of cases this means that they are added to ZONE_NORMAL.
This has been so since 9d99aaa31f ("[PATCH] x86_64: Support memory
hotadd without sparsemem") and it wasn't a big deal back then because
movable onlining didn't exist yet.

Much later memory hotplug wanted to (ab)use ZONE_MOVABLE for movable
onlining 511c2aba8f ("mm, memory-hotplug: dynamic configure movable
memory and portion memory") and then things got more complicated.
Rather than reconsidering the zone association which was no longer
needed (because the memory hotplug already depended on SPARSEMEM) a
convoluted semantic of zone shifting has been developed.  Only the
currently last memblock or the one adjacent to the zone_movable can be
onlined movable.  This essentially means that the online type changes as
the new memblocks are added.

Let's simulate memory hot online manually
  $ echo 0x100000000 > /sys/devices/system/memory/probe
  $ grep . /sys/devices/system/memory/memory32/valid_zones
  Normal Movable

  $ echo $((0x100000000+(128<<20))) > /sys/devices/system/memory/probe
  $ grep . /sys/devices/system/memory/memory3?/valid_zones
  /sys/devices/system/memory/memory32/valid_zones:Normal
  /sys/devices/system/memory/memory33/valid_zones:Normal Movable

  $ echo $((0x100000000+2*(128<<20))) > /sys/devices/system/memory/probe
  $ grep . /sys/devices/system/memory/memory3?/valid_zones
  /sys/devices/system/memory/memory32/valid_zones:Normal
  /sys/devices/system/memory/memory33/valid_zones:Normal
  /sys/devices/system/memory/memory34/valid_zones:Normal Movable

  $ echo online_movable > /sys/devices/system/memory/memory34/state
  $ grep . /sys/devices/system/memory/memory3?/valid_zones
  /sys/devices/system/memory/memory32/valid_zones:Normal
  /sys/devices/system/memory/memory33/valid_zones:Normal Movable
  /sys/devices/system/memory/memory34/valid_zones:Movable Normal

This is an awkward semantic because an udev event is sent as soon as the
block is onlined and an udev handler might want to online it based on
some policy (e.g.  association with a node) but it will inherently race
with new blocks showing up.

This patch changes the physical online phase to not associate pages with
any zone at all.  All the pages are just marked reserved and wait for
the onlining phase to be associated with the zone as per the online
request.  There are only two requirements

	- existing ZONE_NORMAL and ZONE_MOVABLE cannot overlap

	- ZONE_NORMAL precedes ZONE_MOVABLE in physical addresses

the latter one is not an inherent requirement and can be changed in the
future.  It preserves the current behavior and made the code slightly
simpler.  This is subject to change in future.

This means that the same physical online steps as above will lead to the
following state: Normal Movable

  /sys/devices/system/memory/memory32/valid_zones:Normal Movable
  /sys/devices/system/memory/memory33/valid_zones:Normal Movable

  /sys/devices/system/memory/memory32/valid_zones:Normal Movable
  /sys/devices/system/memory/memory33/valid_zones:Normal Movable
  /sys/devices/system/memory/memory34/valid_zones:Normal Movable

  /sys/devices/system/memory/memory32/valid_zones:Normal Movable
  /sys/devices/system/memory/memory33/valid_zones:Normal Movable
  /sys/devices/system/memory/memory34/valid_zones:Movable

Implementation:
The current move_pfn_range is reimplemented to check the above
requirements (allow_online_pfn_range) and then updates the respective
zone (move_pfn_range_to_zone), the pgdat and links all the pages in the
pfn range with the zone/node.  __add_pages is updated to not require the
zone and only initializes sections in the range.  This allowed to
simplify the arch_add_memory code (s390 could get rid of quite some of
code).

devm_memremap_pages is the only user of arch_add_memory which relies on
the zone association because it only hooks into the memory hotplug only
half way.  It uses it to associate the new memory with ZONE_DEVICE but
doesn't allow it to be {on,off}lined via sysfs.  This means that this
particular code path has to call move_pfn_range_to_zone explicitly.

The original zone shifting code is kept in place and will be removed in
the follow up patch for an easier review.

Please note that this patch also changes the original behavior when
offlining a memory block adjacent to another zone (Normal vs.  Movable)
used to allow to change its movable type.  This will be handled later.

[richard.weiyang@gmail.com: simplify zone_intersects()]
  Link: http://lkml.kernel.org/r/20170616092335.5177-1-richard.weiyang@gmail.com
[richard.weiyang@gmail.com: remove duplicate call for set_page_links]
  Link: http://lkml.kernel.org/r/20170616092335.5177-2-richard.weiyang@gmail.com
[akpm@linux-foundation.org: remove unused local `i']
Link: http://lkml.kernel.org/r/20170515085827.16474-12-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # For s390 bits
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Daniel Kiper <daniel.kiper@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Tobias Regnery <tobias.regnery@gmail.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:32 -07:00
Michal Hocko
d336e94e44 mm, vmstat: skip reporting offline pages in pagetypeinfo
pagetypeinfo_showblockcount_print skips over invalid pfns but it would
report pages which are offline because those have a valid pfn.  Their
migrate type is misleading at best.

Now that we have pfn_to_online_page() we can use it instead of
pfn_valid() and fix this.

[mhocko@suse.com: fix build]
  Link: http://lkml.kernel.org/r/20170519072225.GA13041@dhcp22.suse.cz
Link: http://lkml.kernel.org/r/20170515085827.16474-11-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Joonsoo Kim <js1304@gmail.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Daniel Kiper <daniel.kiper@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Tobias Regnery <tobias.regnery@gmail.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:32 -07:00