android_kernel_motorola_sm6375/Documentation
Repository files (latest commit first)
Filename Latest commit message Latest commit date
Johannes Weiner 24900f3596 mm: memcontrol: deprecate charge moving
commit da34a8484d162585e22ed8c1e4114aa2f60e3567 upstream.

Charge moving mode in cgroup1 allows memory to follow tasks as they
migrate between cgroups.  This is, and always has been, a questionable
thing to do - for several reasons.

First, it's expensive.  Pages need to be identified, locked and isolated
from various MM operations, and reassigned, one by one.

Second, it's unreliable.  Once pages are charged to a cgroup, there isn't
always a clear owner task anymore.  Cache isn't moved at all, for example.
Mapped memory is moved - but if trylocking or isolating a page fails,
it's arbitrarily left behind.  Frequent moving between domains may leave a
task's memory scattered all over the place.

Third, it isn't really needed.  Launcher tasks can kick off workload tasks
directly in their target cgroup.  Using dedicated per-workload groups
allows fine-grained policy adjustments - no need to move tasks and their
physical pages between control domains.  The feature was never
forward-ported to cgroup2, and it hasn't been missed.

Despite it being a niche usecase, the maintenance overhead of supporting
it is enormous.  Because pages are moved while they are live and subject
to various MM operations, the synchronization rules are complicated.
There are lock_page_memcg() in MM and FS code, which non-cgroup people
don't understand.  In some cases we've been able to shift code and cgroup
API calls around such that we can rely on native locking as much as
possible.  But that's fragile, and sometimes we need to hold MM locks for
longer than we otherwise would (pte lock e.g.).

Mark the feature deprecated. Hopefully we can remove it soon.

And backport into -stable kernels so that people who develop against
earlier kernels are warned about this deprecation as early as possible.

[akpm@linux-foundation.org: fix memory.rst underlining]
Link: https://lkml.kernel.org/r/Y5COd+qXwk/S+n8N@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-11 16:44:05 +01:00
..
ABI docs: Fix path paste-o for /sys/kernel/warn_count 2023-02-06 07:52:50 +01:00
accounting psi: Fix uaf issue when psi trigger is destroyed while being polled 2022-02-05 12:35:36 +01:00
admin-guide mm: memcontrol: deprecate charge moving 2023-03-11 16:44:05 +01:00
arm ARM: 9012/1: move device tree mapping out of linear region 2021-05-19 10:08:32 +02:00
arm64 arm64: errata: Remove AES hwcap for COMPAT tasks 2022-10-29 10:20:35 +02:00
block
bpf
cdrom
core-api XArray: add xas_split 2021-06-10 13:37:14 +02:00
cpu-freq
crypto
dev-tools docs/scripts/gdb: add necessary make scripts_gdb step 2023-03-11 16:43:57 +01:00
devicetree dt-bindings: phy: g12a-usb3-pcie-phy: fix compatible string documentation 2023-01-24 07:18:01 +01:00
doc-guide
driver-api spi: Update reference to struct spi_controller 2023-01-18 11:41:01 +01:00
EDID
fault-injection debugfs: fix error when writing negative value to atomic_t debugfs file 2023-01-18 11:40:56 +01:00
fb fbdev: fix numbering of fbcon options 2020-02-24 08:36:42 +01:00
features
filesystems ext4, doc: fix incorrect h_reserved size 2022-04-27 13:50:50 +02:00
firmware-guide Documentation: ACPI: EINJ: Fix obsolete example 2022-08-25 11:18:21 +02:00
firmware_class
fpga
gpu
hid
hwmon Revert "hwmon: Make chip parameter for with_info API mandatory" 2022-06-25 12:44:36 +02:00
i2c
ia64
ide
iio
infiniband
input Input: iforce - add support for Boeder Force Feedback Wheel 2022-09-20 12:27:59 +02:00
ioctl
isdn
kbuild kbuild: support LLVM=1 to switch the default tools to Clang/LLVM 2020-08-26 10:40:47 +02:00
kernel-hacking
leds
livepatch
locking
m68k
maintainer
media media: videodev2.h: RGB BT2020 and HSV are always full range 2020-11-05 11:43:15 +01:00
mic
mips
misc-devices
netlabel
networking Documentation: fix sctp_wmem in ip-sysctl.rst 2022-08-03 11:59:40 +02:00
nios2
openrisc
parisc
PCI
pcmcia
power
powerpc
process docs: update mediator contact information in CoC doc 2022-11-25 17:42:20 +01:00
RCU
riscv
s390
scheduler
scsi scsi: smartpqi: Update attribute name to driver_version 2020-01-17 19:48:27 +01:00
security Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity 2019-09-27 19:37:27 -07:00
sh
sound ALSA: hda/realtek: Add alc256-samsung-headphone fixup 2022-04-15 14:18:25 +02:00
sparc
sphinx docs: Fix the docs build with Sphinx 6.0 2023-01-18 11:42:01 +01:00
sphinx-static
spi
target tweewide: Fix most Shebang lines 2021-05-22 11:38:30 +02:00
timers
trace tracing/histogram: Update document for KEYS_MAX size 2022-11-10 17:57:55 +01:00
translations
usb USB: rio500: Remove Rio 500 kernel driver 2019-10-04 10:53:36 +02:00
userspace-api Documentation: seccomp: Fix user notification documentation 2021-06-03 08:59:03 +02:00
virt KVM: s390: disable migration mode when dirty tracking is disabled 2023-03-11 16:44:01 +01:00
virtual
vm arm: remove CONFIG_ARCH_HAS_HOLES_MEMORYMODEL 2022-05-15 19:54:46 +02:00
w1
watchdog
x86 x86/CPU/AMD: Save AMD NodeId as cpu_die_id 2020-12-30 11:51:47 +01:00
xtensa xtensa: fix TLBTEMP area placement 2020-11-24 13:29:22 +01:00
.gitignore
asm-annotations.rst linkage: Introduce new macros for assembler symbols 2020-11-10 12:37:24 +01:00
atomic_bitops.txt locking/atomic: Make test_and_*_bit() ordered on failure 2022-08-25 11:18:31 +02:00
atomic_t.txt
bus-virt-phys-mapping.txt
Changes
CodingStyle
conf.py docs/conf.py: Cope with removal of language=None in Sphinx 5.0.0 2022-06-14 18:11:49 +02:00
COPYING-logo
crc32.txt
debugging-modules.txt
debugging-via-ohci1394.txt
digsig.txt
DMA-API-HOWTO.txt
DMA-API.txt
DMA-attributes.txt Reinstate some of "swiotlb: rework "fix info leak with DMA_FROM_DEVICE"" 2022-05-25 09:14:38 +02:00
DMA-ISA-LPC.txt
docutils.conf
dontdiff
futex-requeue-pi.txt
hwspinlock.txt
index.rst linkage: Introduce new macros for assembler symbols 2020-11-10 12:37:24 +01:00
io-mapping.txt
io_ordering.txt
IPMI.txt
IRQ-affinity.txt
IRQ-domain.txt
IRQ.txt
irqflags-tracing.txt
Kconfig
kobject.txt
kprobes.txt
kref.txt
logo.gif
lzo.txt lib/lzo: fix ambiguous encoding bug in lzo-rle 2020-06-17 16:40:28 +02:00
mailbox.txt
Makefile
memory-barriers.txt
nommu-mmap.txt
padata.txt
percpu-rw-semaphore.txt
pi-futex.txt
preempt-locking.txt
rbtree.txt
remoteproc.txt
robust-futex-ABI.txt
robust-futexes.txt
rpmsg.txt
speculation.txt
static-keys.txt
SubmittingPatches
tee.txt
this_cpu_ops.txt
unaligned-memory-access.txt
xz.txt