linux/include
Muchun Song 380780e718 mm: memcontrol: convert NR_FILE_PMDMAPPED account to pages
Currently we use struct per_cpu_nodestat to cache the vmstat counters,
which leads to inaccurate statistics especially THP vmstat counters.  In
the systems with hundreds of processors it can be GBs of memory.  For
example, for a 96 CPUs system, the threshold is the maximum number of 125.
And the per cpu counters can cache 23.4375 GB in total.

The THP page is already a form of batched addition (it will add 512 worth
of memory in one go) so skipping the batching seems like sensible.
Although every THP stats update overflows the per-cpu counter, resorting
to atomic global updates.  But it can make the statistics more accuracy
for the THP vmstat counters.

So we convert the NR_FILE_PMDMAPPED account to pages.  This patch is
consistent with 8f182270df ("mm/swap.c: flush lru pvecs on compound page
arrival").  Doing this also can make the unit of vmstat counters more
unified.  Finally, the unit of the vmstat counters are pages, kB and
bytes.  The B/KB suffix can tell us that the unit is bytes or kB.  The
rest which is without suffix are pages.

Link: https://lkml.kernel.org/r/20201228164110.2838-7-songmuchun@bytedance.com
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: NeilBrown <neilb@suse.de>
Cc: Pankaj Gupta <pankaj.gupta@cloud.ionos.com>
Cc: Rafael. J. Wysocki <rafael@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Roman Gushchin <guro@fb.com>
Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-24 13:38:29 -08:00
..
acpi IOMMU Updates for Linux v5.12 2021-02-22 10:31:29 -08:00
asm-generic Modules updates for v5.12 2021-02-23 10:15:33 -08:00
clocksource
crypto Keyrings miscellany 2021-02-23 16:09:23 -08:00
drm
dt-bindings Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2021-02-23 14:56:23 -08:00
keys
kunit
kvm
linux mm: memcontrol: convert NR_FILE_PMDMAPPED account to pages 2021-02-24 13:38:29 -08:00
math-emu
media Fixes around VM_FPNMAP and follow_pfn 2021-02-22 17:45:02 -08:00
memory
misc
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next 2021-02-17 13:19:24 -08:00
pcmcia
ras
rdma RDMA/ipoib: Remove racy Subnet Manager sendonly join checks 2021-02-16 14:42:58 -04:00
scsi
soc IOMMU Updates for Linux v5.12 2021-02-22 10:31:29 -08:00
sound ASoC: Updates for v5.12 2021-02-17 21:16:27 +01:00
target
trace mm, tracing: record slab name for kmem_cache_free() 2021-02-24 13:38:26 -08:00
uapi Changes in gfs2: 2021-02-23 14:04:04 -08:00
vdso
video
xen x86: 2021-02-21 13:31:43 -08:00