linux_dsm_epyc7002/arch/mips
Kirill A. Shutemov ddc58f27f9 mm: drop tail page refcounting
Tail page refcounting is utterly complicated and painful to support.

It uses ->_mapcount on tail pages to store how many times this page is
pinned.  get_page() bumps ->_mapcount on tail page in addition to
->_count on head.  This information is required by split_huge_page() to
be able to distribute pins from head of compound page to tails during
the split.

We will need ->_mapcount to account PTE mappings of subpages of the
compound page.  We eliminate need in current meaning of ->_mapcount in
tail pages by forbidding split entirely if the page is pinned.

The only user of tail page refcounting is THP which is marked BROKEN for
now.

Let's drop all this mess.  It makes get_page() and put_page() much
simpler.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Jerome Marchand <jmarchan@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Christoph Lameter <cl@linux.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>
2016-01-15 17:56:32 -08:00
..
alchemy mips: nand: make use of mtd_to_nand() where appropriate 2015-12-08 13:03:07 -08:00
ar7
ath25
ath79 MIPS: ath79: Add a machine entry for booting OF machines 2015-11-20 15:44:57 +01:00
bcm47xx ssb: pick SoC invariants code from MIPS BCM47xx arch 2015-12-16 16:36:25 +02:00
bcm63xx Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2015-11-15 09:10:53 -08:00
bmips MIPS: Make MIPS_CMDLINE_DTB default 2015-11-11 08:38:37 +01:00
boot Merge remote-tracking branches 'regmap/topic/mmio', 'regmap/topic/rbtree' and 'regmap/topic/seq' into regmap-next 2016-01-05 19:07:18 +00:00
cavium-octeon Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2015-11-15 09:10:53 -08:00
cobalt
configs Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2015-11-15 09:10:53 -08:00
dec
emma
fw
include soreuseport: setsockopt SO_ATTACH_REUSEPORT_[CE]BPF 2016-01-04 22:49:59 -05:00
jazz
jz4740
kernel Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching 2016-01-14 16:38:02 -08:00
kvm MIPS: KVM: Uninit VCPU in vcpu_create error path 2015-11-18 12:25:36 +01:00
lantiq MIPS: Make MIPS_CMDLINE_DTB default 2015-11-11 08:38:37 +01:00
lasat [mips] switch pvc_proc_cleanup() to remove_proc_subtree() 2015-12-23 10:41:38 -05:00
lib MIPS: uaccess: Take EVA into account in [__]clear_user 2015-12-22 11:58:43 +01:00
loongson32
loongson64 MIPS: Loongson: Cleanup CONFIG_LOONGSON_SUSPEND. 2015-11-11 08:38:28 +01:00
math-emu
mm mm: drop tail page refcounting 2016-01-15 17:56:32 -08:00
mti-malta MIPS: Malta: Register UP SMP ops if all else fails 2015-11-11 08:35:49 +01:00
mti-sead3
net net: filter: make JITs zero A for SKF_AD_ALU_XOR_X 2016-01-06 00:43:52 -05:00
netlogic MIPS: Make MIPS_CMDLINE_DTB default 2015-11-11 08:38:37 +01:00
oprofile
paravirt
pci MIPS: Fix build error due to unused variables. 2015-12-22 15:21:18 +01:00
pistachio Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2015-11-15 09:10:53 -08:00
pmcs-msp71xx MIPS: Fix build error due to unused variables. 2015-12-22 15:21:18 +01:00
pnx833x mips: nand: make use of mtd_to_nand() where appropriate 2015-12-08 13:03:07 -08:00
power
ralink Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2015-11-15 09:10:53 -08:00
rb532 mips: nand: make use of mtd_to_nand() where appropriate 2015-12-08 13:03:07 -08:00
sgi-ip22
sgi-ip27
sgi-ip32
sibyte
sni MIPS: Fix build error due to unused variables. 2015-12-22 15:21:18 +01:00
txx9
vdso Fix ld-version.sh to handle large 3rd version part 2016-01-04 10:22:52 +01:00
vr41xx
xilfpga Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2015-11-15 09:10:53 -08:00
Kbuild MIPS: Initial implementation of a VDSO 2015-11-11 08:36:36 +01:00
Kbuild.platforms MIPS: xilfpga: Add mipsfpga platform code 2015-11-11 08:38:44 +01:00
Kconfig MIPS: vmlinux: create a section for appended DTB 2015-11-12 11:35:48 +01:00
Kconfig.debug MIPS: CPS: Early debug using an ns16550-compatible UART 2015-11-11 08:34:25 +01:00
Makefile