linux/mm
Linus Torvalds edf445ad7c Merge branch 'hugepage-fallbacks' (hugepatch patches from David Rientjes)
Merge hugepage allocation updates from David Rientjes:
 "We (mostly Linus, Andrea, and myself) have been discussing offlist how
  to implement a sane default allocation strategy for hugepages on NUMA
  platforms.

  With these reverts in place, the page allocator will happily allocate
  a remote hugepage immediately rather than try to make a local hugepage
  available. This incurs a substantial performance degradation when
  memory compaction would have otherwise made a local hugepage
  available.

  This series reverts those reverts and attempts to propose a more sane
  default allocation strategy specifically for hugepages. Andrea
  acknowledges this is likely to fix the swap storms that he originally
  reported that resulted in the patches that removed __GFP_THISNODE from
  hugepage allocations.

  The immediate goal is to return 5.3 to the behavior the kernel has
  implemented over the past several years so that remote hugepages are
  not immediately allocated when local hugepages could have been made
  available because the increased access latency is untenable.

  The next goal is to introduce a sane default allocation strategy for
  hugepages allocations in general regardless of the configuration of
  the system so that we prevent thrashing of local memory when
  compaction is unlikely to succeed and can prefer remote hugepages over
  remote native pages when the local node is low on memory."

Note on timing: this reverts the hugepage VM behavior changes that got
introduced fairly late in the 5.3 cycle, and that fixed a huge
performance regression for certain loads that had been around since
4.18.

Andrea had this note:

 "The regression of 4.18 was that it was taking hours to start a VM
  where 3.10 was only taking a few seconds, I reported all the details
  on lkml when it was finally tracked down in August 2018.

     https://lore.kernel.org/linux-mm/20180820032640.9896-2-aarcange@redhat.com/

  __GFP_THISNODE in MADV_HUGEPAGE made the above enterprise vfio
  workload degrade like in the "current upstream" above. And it still
  would have been that bad as above until 5.3-rc5"

where the bad behavior ends up happening as you fill up a local node,
and without that change, you'd get into the nasty swap storm behavior
due to compaction working overtime to make room for more memory on the
nodes.

As a result 5.3 got the two performance fix reverts in rc5.

However, David Rientjes then noted that those performance fixes in turn
regressed performance for other loads - although not quite to the same
degree.  He suggested reverting the reverts and instead replacing them
with two small changes to how hugepage allocations are done (patch
descriptions rephrased by me):

 - "avoid expensive reclaim when compaction may not succeed": just admit
   that the allocation failed when you're trying to allocate a huge-page
   and compaction wasn't successful.

 - "allow hugepage fallback to remote nodes when madvised": when that
   node-local huge-page allocation failed, retry without forcing the
   local node.

but by then I judged it too late to replace the fixes for a 5.3 release.
So 5.3 was released with behavior that harked back to the pre-4.18 logic.

But now we're in the merge window for 5.4, and we can see if this
alternate model fixes not just the horrendous swap storm behavior, but
also restores the performance regression that the late reverts caused.

Fingers crossed.

* emailed patches from David Rientjes <rientjes@google.com>:
  mm, page_alloc: allow hugepage fallback to remote nodes when madvised
  mm, page_alloc: avoid expensive reclaim when compaction may not succeed
  Revert "Revert "Revert "mm, thp: consolidate THP gfp handling into alloc_hugepage_direct_gfpmask""
  Revert "Revert "mm, thp: restore node-local hugepage allocations""
2019-09-28 14:26:47 -07:00
..
kasan mm: introduce compound_nr() 2019-09-24 15:54:08 -07:00
backing-dev.c writeback: Separate out wb_get_lookup() from wb_get_create() 2019-08-27 09:22:38 -06:00
balloon_compaction.c mm/balloon_compaction: suppress allocation warnings 2019-09-04 07:42:01 -04:00
cleancache.c Driver Core and debugfs changes for 5.3-rc1 2019-07-12 12:24:03 -07:00
cma.c mm/cma.c: fail if fixed declaration can't be honored 2019-07-16 19:23:21 -07:00
cma.h
cma_debug.c mm/cma_debug.c: fix the break condition in cma_maxchunk_get() 2019-05-14 09:47:45 -07:00
compaction.c mm/compaction.c: remove unnecessary zone parameter in isolate_migratepages() 2019-09-24 15:54:10 -07:00
debug.c mm: update references to page _refcount 2019-05-14 19:52:47 -07:00
debug_page_ref.c
dmapool.c mm: security: introduce init_on_alloc=1 and init_on_free=1 boot options 2019-07-12 11:05:46 -07:00
early_ioremap.c
fadvise.c fs: Export generic_fadvise() 2019-08-30 22:43:58 -07:00
failslab.c mm/failslab.c: by default, do not fail allocations with direct reclaim only 2019-07-12 11:05:43 -07:00
filemap.c mm,thp: avoid writes to file with THP in pagecache 2019-09-24 15:54:11 -07:00
frame_vector.c mm: untag user pointers in get_vaddr_frames 2019-09-25 17:51:41 -07:00
frontswap.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 482 2019-06-19 17:09:52 +02:00
gup.c mm: untag user pointers in mm/gup.c 2019-09-25 17:51:41 -07:00
gup_benchmark.c mm/gup: replace get_user_pages_longterm() with FOLL_LONGTERM 2019-05-14 09:47:45 -07:00
highmem.c
hmm.c pagewalk: separate function pointers from iterator data 2019-09-07 04:28:04 -03:00
huge_memory.c Merge branch 'hugepage-fallbacks' (hugepatch patches from David Rientjes) 2019-09-28 14:26:47 -07:00
hugetlb.c hugetlbfs: don't retry when pool page allocations start to fail 2019-09-24 15:54:10 -07:00
hugetlb_cgroup.c mm: introduce compound_nr() 2019-09-24 15:54:08 -07:00
hwpoison-inject.c hwpoison-inject: no need to check return value of debugfs_create functions 2019-06-03 15:39:40 +02:00
init-mm.c mm: use CPU_BITS_NONE to initialize init_mm.cpu_bitmask 2019-09-24 15:54:10 -07:00
internal.h mm: introduce MADV_COLD 2019-09-25 17:51:41 -07:00
interval_tree.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 248 2019-06-19 17:09:08 +02:00
Kconfig mm,thp: add read-only THP support for (non-shmem) FS 2019-09-24 15:54:11 -07:00
Kconfig.debug mm, page_owner, debug_pagealloc: save and dump freeing stack trace 2019-09-24 15:54:08 -07:00
khugepaged.c khugepaged: enable collapse pmd for pte-mapped THP 2019-09-24 15:54:11 -07:00
kmemleak-test.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 333 2019-06-05 17:37:06 +02:00
kmemleak.c mm/kmemleak.c: record the current memory pool size 2019-09-24 15:54:07 -07:00
ksm.c mm: move memcmp_pages() and pages_identical() 2019-09-24 15:54:11 -07:00
list_lru.c mm: memcg/slab: stop setting page->mem_cgroup pointer for slab pages 2019-07-12 11:05:44 -07:00
maccess.c The main changes in this release include: 2019-07-18 11:51:00 -07:00
madvise.c mm: factor out common parts between MADV_COLD and MADV_PAGEOUT 2019-09-25 17:51:41 -07:00
Makefile mm: silence -Woverride-init/initializer-overrides 2019-09-24 15:54:10 -07:00
memblock.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
memcontrol.c memcg, kmem: do not fail __GFP_NOFAIL charges 2019-09-25 17:51:39 -07:00
memfd.c mm: page cache: store only head pages in i_pages 2019-09-24 15:54:08 -07:00
memory-failure.c HMM patches for 5.3 2019-07-14 19:42:11 -07:00
memory.c mm: do not hash address in print_bad_pte() 2019-09-24 15:54:09 -07:00
memory_hotplug.c mm/memory_hotplug.c: s/is/if 2019-09-24 15:54:09 -07:00
mempolicy.c Merge branch 'hugepage-fallbacks' (hugepatch patches from David Rientjes) 2019-09-28 14:26:47 -07:00
mempool.c docs/core-api/mm: fix return value descriptions in mm/ 2019-03-05 21:07:20 -08:00
memremap.c Merge branch 'odp_fixes' into hmm.git 2019-08-21 20:58:18 -03:00
memtest.c
migrate.c mm: untag user pointers passed to memory syscalls 2019-09-25 17:51:41 -07:00
mincore.c mm: untag user pointers passed to memory syscalls 2019-09-25 17:51:41 -07:00
mlock.c mm: untag user pointers passed to memory syscalls 2019-09-25 17:51:41 -07:00
mm_init.c treewide: Add SPDX license identifier for missed files 2019-05-21 10:50:45 +02:00
mmap.c mm: untag user pointers in mmap/munmap/mremap/brk 2019-09-25 17:51:41 -07:00
mmu_context.c
mmu_gather.c mm: remove quicklist page table caches 2019-09-24 15:54:09 -07:00
mmu_notifier.c mm, notifier: Catch sleeping/blocking for !blockable 2019-09-07 04:28:05 -03:00
mmzone.c
mprotect.c mm: untag user pointers passed to memory syscalls 2019-09-25 17:51:41 -07:00
mremap.c mm: untag user pointers in mmap/munmap/mremap/brk 2019-09-25 17:51:41 -07:00
msync.c mm: untag user pointers passed to memory syscalls 2019-09-25 17:51:41 -07:00
nommu.c mm: introduce page_size() 2019-09-24 15:54:08 -07:00
oom_kill.c mm: introduce MADV_COLD 2019-09-25 17:51:41 -07:00
page-writeback.c writeback, memcg: Implement foreign dirty flushing 2019-08-27 09:22:38 -06:00
page_alloc.c Merge branch 'hugepage-fallbacks' (hugepatch patches from David Rientjes) 2019-09-28 14:26:47 -07:00
page_counter.c
page_ext.c mm, debug_pagealloc: use a page type instead of page_ext flag 2019-07-12 11:05:43 -07:00
page_idle.c mm/page_idle.c: fix oops because end_pfn is larger than max_pfn 2019-06-29 16:43:45 +08:00
page_io.c mm, swap: use rbtree for swap_extent 2019-07-12 11:05:43 -07:00
page_isolation.c mm/page_isolation.c: change the prototype of undo_isolate_page_range() 2019-07-12 11:05:43 -07:00
page_owner.c mm, page_owner, debug_pagealloc: save and dump freeing stack trace 2019-09-24 15:54:08 -07:00
page_poison.c mm/page_poison.c: fix a typo in a comment 2019-09-24 15:54:08 -07:00
page_vma_mapped.c mm: introduce page_size() 2019-09-24 15:54:08 -07:00
pagewalk.c pagewalk: use lockdep_assert_held for locking validation 2019-09-07 04:28:04 -03:00
percpu-internal.h percpu: convert chunk hints to be based on pcpu_block_md 2019-03-13 12:25:31 -07:00
percpu-km.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428 2019-06-05 17:37:16 +02:00
percpu-stats.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428 2019-06-05 17:37:16 +02:00
percpu-vm.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428 2019-06-05 17:37:16 +02:00
percpu.c percpu: Use struct_size() helper 2019-09-04 13:40:49 -07:00
pgtable-generic.c
process_vm_access.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
readahead.c treewide: Add SPDX license identifier for missed files 2019-05-21 10:50:45 +02:00
rmap.c mm,thp: add read-only THP support for (non-shmem) FS 2019-09-24 15:54:11 -07:00
rodata_test.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441 2019-06-05 17:37:17 +02:00
shmem.c Merge branch 'hugepage-fallbacks' (hugepatch patches from David Rientjes) 2019-09-28 14:26:47 -07:00
shuffle.c mm: maintain randomization of page free lists 2019-05-14 19:52:48 -07:00
shuffle.h mm: maintain randomization of page free lists 2019-05-14 19:52:48 -07:00
slab.c mm: security: introduce init_on_alloc=1 and init_on_free=1 boot options 2019-07-12 11:05:46 -07:00
slab.h mm, slab: move memcg_cache_params structure to mm/slab.h 2019-09-24 15:54:07 -07:00
slab_common.c mm, slab: extend slab/shrink to shrink all memcg caches 2019-09-24 15:54:07 -07:00
slob.c mm: introduce page_size() 2019-09-24 15:54:08 -07:00
slub.c mm: introduce page_size() 2019-09-24 15:54:08 -07:00
sparse-vmemmap.c mm/sparsemem: convert kmalloc_section_memmap() to populate_section_memmap() 2019-07-18 17:08:07 -07:00
sparse.c mm/sparse.c: remove NULL check in clear_hwpoisoned_pages() 2019-09-24 15:54:09 -07:00
swap.c mm: introduce MADV_COLD 2019-09-25 17:51:41 -07:00
swap_cgroup.c
swap_slots.c
swap_state.c mm: page cache: store only head pages in i_pages 2019-09-24 15:54:08 -07:00
swapfile.c vfs: don't allow writes to swap files 2019-08-20 07:55:16 -07:00
truncate.c treewide: Add SPDX license identifier for missed files 2019-05-21 10:50:45 +02:00
usercopy.c usercopy: Avoid HIGHMEM pfn warning 2019-09-17 15:20:17 -07:00
userfaultfd.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 499 2019-06-19 17:09:53 +02:00
util.c arm64, mm: make randomization selected by generic topdown mmap layout 2019-09-24 15:54:11 -07:00
vmacache.c
vmalloc.c augmented rbtree: add new RB_DECLARE_CALLBACKS_MAX macro 2019-09-25 17:51:39 -07:00
vmpressure.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
vmscan.c mm: introduce MADV_PAGEOUT 2019-09-25 17:51:41 -07:00
vmstat.c mm,thp: stats for file backed THP 2019-09-24 15:54:11 -07:00
workingset.c mm: workingset: fix vmstat counters for shadow nodes 2019-08-13 16:06:52 -07:00
z3fold.c z3fold: fix memory leak in kmem cache 2019-09-24 15:54:10 -07:00
zbud.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
zpool.c zpool: add malloc_support_movable to zpool_driver 2019-09-24 15:54:12 -07:00
zsmalloc.c mm/zsmalloc.c: fix a -Wunused-function warning 2019-09-24 15:54:12 -07:00
zswap.c zswap: do not map same object twice 2019-09-24 15:54:12 -07:00