linux-stable/mm
Andrea Arcangeli 0ba1d0f7c4 ksm: cleanup stable_node chain collapse case
Patch series "KSMscale cleanup/optimizations".

There are no fixes here it's just minor cleanups and optimizations.

1/3 removes makes the "fix" for the stale stable_node fall in the
    standard case without introducing new cases.  Setting stable_node to
    NULL was marginally safer, but stale pointer is still wiped from the
    caller, this looks cleaner.

2/3 should fix the false positive from Dan's static checker.

3/3 is a microoptimization to apply the the refile of future merge
    candidate dups at the head of the chain in all cases and to skip it in
    one case where we did it and but it was a noop (to avoid checking if
    it was already at the head but now we've to check it anyway so it got
    optimized away).

This patch (of 3):

When the stable_node chain is collapsed we can as well set the caller
stable_node to match the returned stable_node_dup in chain_prune().

This way the collapse case becomes indistinguishable from the regular
stable_node case and we can remove two branches from the KSM page
migration handling slow paths.

While it was all correct this looks cleaner (and faster) as the caller has
to deal with fewer special cases.

Link: http://lkml.kernel.org/r/20170518173721.22316-2-aarcange@redhat.com
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Evgheni Dereveanchin <ederevea@redhat.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Petr Holasek <pholasek@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Gavin Guo <gavin.guo@canonical.com>
Cc: Jay Vosburgh <jay.vosburgh@canonical.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:31 -07:00
..
kasan Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-05-10 10:30:46 -07:00
backing-dev.c bdi: Drop 'parent' argument from bdi_register[_va]() 2017-04-20 12:09:55 -06:00
balloon_compaction.c
bootmem.c mm/bootmem.c: cosmetic improvement of code readability 2017-02-22 16:41:29 -08:00
cleancache.c fs: switch ->s_uuid to uuid_t 2017-06-05 16:59:12 +02:00
cma.c cma: Introduce cma_for_each_area 2017-04-18 20:41:12 +02:00
cma.h cma: Store a name in the cma structure 2017-04-18 20:41:12 +02:00
cma_debug.c cma: Store a name in the cma structure 2017-04-18 20:41:12 +02:00
compaction.c mm, compaction: finish whole pageblock to reduce fragmentation 2017-05-08 17:15:10 -07:00
debug.c mm, debug: print raw struct page data in __dump_page() 2016-12-12 18:55:08 -08:00
debug_page_ref.c
dmapool.c lib/vsprintf.c: remove %Z support 2017-02-27 18:43:47 -08:00
early_ioremap.c
fadvise.c mm: fadvise: avoid expensive remote LRU cache draining after FADV_DONTNEED 2016-12-20 09:48:46 -08:00
failslab.c
filemap.c Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-07-03 13:08:04 -07:00
frame_vector.c treewide: use kv[mz]alloc* rather than opencoded variants 2017-05-08 17:15:13 -07:00
frontswap.c
gup.c Merge branch 'linus' into x86/mm, to pick up fixes 2017-06-22 10:57:28 +02:00
highmem.c
huge_memory.c thp, mm: fix crash due race in MADV_FREE handling 2017-07-06 16:24:29 -07:00
hugetlb.c mm/hugetlb: report -EHWPOISON not -EFAULT when FOLL_HWPOISON is specified 2017-06-02 15:07:38 -07:00
hugetlb_cgroup.c
hwpoison-inject.c mm: hwpoison: call shake_page() unconditionally 2017-05-03 15:52:12 -07:00
init-mm.c mm: Add a user_ns owner to mm_struct and fix ptrace permission checks 2016-11-22 11:49:48 -06:00
internal.h mm, compaction: finish whole pageblock to reduce fragmentation 2017-05-08 17:15:10 -07:00
interval_tree.c
Kconfig Merge branch 'for-4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu 2017-07-06 08:59:41 -07:00
Kconfig.debug mm: enable page poisoning early at boot 2017-05-03 15:52:10 -07:00
khugepaged.c mm, thp: remove cond_resched from __collapse_huge_page_copy 2017-06-23 16:15:55 -07:00
kmemcheck.c mm: Rename SLAB_DESTROY_BY_RCU to SLAB_TYPESAFE_BY_RCU 2017-04-18 11:42:36 -07:00
kmemleak-test.c
kmemleak.c mm: fix section name for .data..ro_after_init 2017-03-31 17:13:30 -07:00
ksm.c ksm: cleanup stable_node chain collapse case 2017-07-06 16:24:31 -07:00
list_lru.c mm/list_lru.c: avoid error-path NULL pointer deref 2016-10-27 18:43:42 -07:00
maccess.c
madvise.c mm/madvise: move up the behavior parameter validation 2017-05-03 15:52:11 -07:00
Makefile percpu: expose statistics about percpu memory via debugfs 2017-06-20 15:31:38 -04:00
memblock.c mm: consider memblock reservations for deferred memory initialization sizing 2017-06-02 15:07:38 -07:00
memcontrol.c sched/wait: Disambiguate wq_entry->task_list and wq_head->task_list naming 2017-06-20 12:19:14 +02:00
memory-failure.c mm/memory-failure.c: use compound_head() flags for huge pages 2017-06-17 06:37:05 +09:00
memory.c mm: larger stack guard gap, between vmas 2017-06-19 21:50:20 +08:00
memory_hotplug.c mm, vmscan: prevent kswapd sleeping prematurely due to mismatched classzone_idx 2017-05-03 15:52:09 -07:00
mempolicy.c mm/mempolicy.c: fix error handling in set_mempolicy and mbind. 2017-04-08 10:57:55 -07:00
mempool.c sched/wait: Rename wait_queue_t => wait_queue_entry_t 2017-06-20 12:18:27 +02:00
memtest.c
migrate.c mm: make rmap_one boolean function 2017-05-03 15:52:10 -07:00
mincore.c mm: remove shmem_mapping() shmem_zero_setup() duplicates 2017-02-24 17:46:56 -08:00
mlock.c mlock: fix mlock count can not decrease in race condition 2017-06-02 15:07:38 -07:00
mm_init.c
mmap.c mm/mmap.c: mark protection_map as __ro_after_init 2017-07-06 16:24:31 -07:00
mmu_context.c sched/headers: Prepare to move the task_lock()/unlock() APIs to <linux/sched/task.h> 2017-03-02 08:42:38 +01:00
mmu_notifier.c mm: Use static initialization for "srcu" 2017-04-18 11:38:22 -07:00
mmzone.c mm/mmzone.c: swap likely to unlikely as code logic is different for next_zones_zonelist() 2017-02-22 16:41:29 -08:00
mprotect.c mm: convert generic code to 5-level paging 2017-03-09 11:48:47 -08:00
mremap.c mm: convert generic code to 5-level paging 2017-03-09 11:48:47 -08:00
msync.c
nobootmem.c mm/nobootmem.c: return 0 when start_pfn equals end_pfn 2017-07-06 16:24:31 -07:00
nommu.c mm, vmalloc: use __GFP_HIGHMEM implicitly 2017-05-08 17:15:13 -07:00
oom_kill.c oom: improve oom disable handling 2017-05-03 15:52:10 -07:00
page-writeback.c Add GETFSMAP support; some performance improvements for very large 2017-05-08 11:30:05 -07:00
page_alloc.c mm: consider memblock reservations for deferred memory initialization sizing 2017-06-02 15:07:38 -07:00
page_counter.c
page_ext.c mm: enable page poisoning early at boot 2017-05-03 15:52:10 -07:00
page_idle.c mm: make rmap_one boolean function 2017-05-03 15:52:10 -07:00
page_io.c block: switch bios to blk_status_t 2017-06-09 09:27:32 -06:00
page_isolation.c mm, page_alloc: count movable pages when stealing from pageblock 2017-05-08 17:15:10 -07:00
page_owner.c mm/page_owner: don't define fields on struct page_ext by hard-coding 2016-10-07 18:46:27 -07:00
page_poison.c mm: enable page poisoning early at boot 2017-05-03 15:52:10 -07:00
page_vma_mapped.c mm: fix page_vma_mapped_walk() for ksm pages 2017-04-08 00:47:48 -07:00
pagewalk.c mm: convert generic code to 5-level paging 2017-03-09 11:48:47 -08:00
percpu-internal.h percpu: fix early calls for spinlock in pcpu_stats 2017-06-21 13:53:52 -04:00
percpu-km.c percpu: fix static checker warnings in pcpu_destroy_chunk 2017-06-29 11:23:38 -04:00
percpu-stats.c percpu: expose statistics about percpu memory via debugfs 2017-06-20 15:31:38 -04:00
percpu-vm.c percpu: fix static checker warnings in pcpu_destroy_chunk 2017-06-29 11:23:38 -04:00
percpu.c percpu: resolve err may not be initialized in pcpu_alloc 2017-06-21 12:00:45 -04:00
pgtable-generic.c mm: convert generic code to 5-level paging 2017-03-09 11:48:47 -08:00
process_vm_access.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/mm.h> 2017-03-02 08:42:28 +01:00
quicklist.c
readahead.c mm: don't cap request size based on read-ahead setting 2016-12-12 18:55:08 -08:00
rmap.c mm, x86/mm: Make the batched unmap TLB flush API more generic 2017-05-24 10:18:27 +02:00
rodata_test.c mm: remove rodata_test_data export, add pr_fmt 2017-05-03 15:52:09 -07:00
shmem.c Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-07-03 13:08:04 -07:00
slab.c mm/slab.c: replace open-coded round-up code with ALIGN 2017-07-06 16:24:30 -07:00
slab.h mm: Rename SLAB_DESTROY_BY_RCU to SLAB_TYPESAFE_BY_RCU 2017-04-18 11:42:36 -07:00
slab_common.c mm: allow slab_nomerge to be set at build time 2017-07-06 16:24:31 -07:00
slob.c mm: Rename SLAB_DESTROY_BY_RCU to SLAB_TYPESAFE_BY_RCU 2017-04-18 11:42:36 -07:00
slub.c mm/slub.c: wrap kmem_cache->cpu_partial in config CONFIG_SLUB_CPU_PARTIAL 2017-07-06 16:24:30 -07:00
sparse-vmemmap.c mm: convert generic code to 5-level paging 2017-03-09 11:48:47 -08:00
sparse.c mm, sparsemem: break out of loops early 2017-07-06 16:24:31 -07:00
swap.c mm: move MADV_FREE pages into LRU_INACTIVE_FILE list 2017-05-03 15:52:08 -07:00
swap_cgroup.c swap: cond_resched in swap_cgroup_prepare() 2017-06-17 06:37:05 +09:00
swap_slots.c mm, swap: use kvzalloc to allocate some swap data structures 2017-05-08 17:15:13 -07:00
swap_state.c mm, swap: use kvzalloc to allocate some swap data structures 2017-05-08 17:15:13 -07:00
swapfile.c mm, swap: use kvzalloc to allocate some swap data structures 2017-05-08 17:15:13 -07:00
truncate.c mm: fix data corruption due to stale mmap reads 2017-05-12 15:57:15 -07:00
usercopy.c mm/usercopy: Drop extra is_vmalloc_or_module() check 2017-04-05 12:30:18 -07:00
userfaultfd.c mm: convert generic code to 5-level paging 2017-03-09 11:48:47 -08:00
util.c mm: clarify why we want kmalloc before falling backto vmallock 2017-06-02 15:07:37 -07:00
vmacache.c sched/headers: Prepare to move 'init_task' and 'init_thread_union' from <linux/sched.h> to <linux/sched/task.h> 2017-03-02 08:42:38 +01:00
vmalloc.c mm/vmalloc.c: huge-vmap: fail gracefully on unexpected huge vmap mappings 2017-06-23 16:15:55 -07:00
vmpressure.c mm: correct the comment when reclaimed pages exceed the scanned pages 2017-06-17 06:37:05 +09:00
vmscan.c mm/vmscan.c: fix unsequenced modification and access warning 2017-07-06 16:24:31 -07:00
vmstat.c mm, vmstat: Remove spurious WARN() during zoneinfo print 2017-05-12 15:57:15 -07:00
workingset.c mm: memcontrol: use node page state naming scheme for memcg 2017-05-03 15:52:11 -07:00
z3fold.c z3fold: fix page locking in z3fold_alloc() 2017-04-13 18:24:20 -07:00
zbud.c
zpool.c
zsmalloc.c zsmalloc: expand class bit 2017-04-13 18:24:21 -07:00
zswap.c zswap: don't param_set_charp while holding spinlock 2017-02-27 18:43:45 -08:00