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Johannes Weiner f80c7dab95 mm: memcontrol: use vmalloc fallback for large kmem memcg arrays
For quick per-memcg indexing, slab caches and list_lru structures
maintain linear arrays of descriptors.  As the number of concurrent
memory cgroups in the system goes up, this requires large contiguous
allocations (8k cgroups = order-5, 16k cgroups = order-6 etc.) for every
existing slab cache and list_lru, which can easily fail on loaded
systems.  E.g.:

  mkdir: page allocation failure: order:5, mode:0x14040c0(GFP_KERNEL|__GFP_COMP), nodemask=(null)
  CPU: 1 PID: 6399 Comm: mkdir Not tainted 4.13.0-mm1-00065-g720bbe532b7c-dirty #481
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-20170228_101828-anatol 04/01/2014
  Call Trace:
   ? __alloc_pages_direct_compact+0x4c/0x110
   __alloc_pages_nodemask+0xf50/0x1430
   alloc_pages_current+0x60/0xc0
   kmalloc_order_trace+0x29/0x1b0
   __kmalloc+0x1f4/0x320
   memcg_update_all_list_lrus+0xca/0x2e0
   mem_cgroup_css_alloc+0x612/0x670
   cgroup_apply_control_enable+0x19e/0x360
   cgroup_mkdir+0x322/0x490
   kernfs_iop_mkdir+0x55/0x80
   vfs_mkdir+0xd0/0x120
   SyS_mkdirat+0x6c/0xe0
   SyS_mkdir+0x14/0x20
   entry_SYSCALL_64_fastpath+0x18/0xad
  Mem-Info:
  active_anon:2965 inactive_anon:19 isolated_anon:0
   active_file:100270 inactive_file:98846 isolated_file:0
   unevictable:0 dirty:0 writeback:0 unstable:0
   slab_reclaimable:7328 slab_unreclaimable:16402
   mapped:771 shmem:52 pagetables:278 bounce:0
   free:13718 free_pcp:0 free_cma:0

This output is from an artificial reproducer, but we have repeatedly
observed order-7 failures in production in the Facebook fleet.  These
systems become useless as they cannot run more jobs, even though there
is plenty of memory to allocate 128 individual pages.

Use kvmalloc and kvzalloc to fall back to vmalloc space if these arrays
prove too large for allocating them physically contiguous.

Link: http://lkml.kernel.org/r/20170918184919.20644-1-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-10-03 17:54:25 -07:00
arch m32r: define CPU_BIG_ENDIAN 2017-10-03 17:54:24 -07:00
block block: fix a crash caused by wrong API 2017-09-25 08:56:05 -06:00
certs modsign: add markers to endif-statements in certs/Makefile 2017-07-14 11:01:37 +10:00
crypto crypto: af_alg - update correct dst SGL entry 2017-09-20 17:42:42 +08:00
Documentation Merge branch 'for-4.14-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq 2017-10-03 10:44:03 -07:00
drivers zram: fix null dereference of handle 2017-10-03 17:54:24 -07:00
firmware firmware: Restore support for built-in firmware 2017-09-16 10:58:48 -07:00
fs exec: binfmt_misc: kill the onstack iname[BINPRM_BUF_SIZE] array 2017-10-03 17:54:25 -07:00
include include/linux/bitfield.h: remove 32bit from FIELD_GET comment block 2017-10-03 17:54:25 -07:00
init Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:54:01 -07:00
ipc fix a typo in put_compat_shm_info() 2017-09-25 20:41:46 -04:00
kernel kernel/sysctl.c: remove duplicate UINT_MAX check on do_proc_douintvec_conv() 2017-10-03 17:54:25 -07:00
lib lib/lz4: make arrays static const, reduces object code size 2017-10-03 17:54:25 -07:00
mm mm: memcontrol: use vmalloc fallback for large kmem memcg arrays 2017-10-03 17:54:25 -07:00
net Revert "Bluetooth: Add option for disabling legacy ioctl interfaces" 2017-09-28 13:20:32 -07:00
samples media updates for v4.14-rc1 2017-09-07 12:53:14 -07:00
scripts scripts/spelling.txt: add more spelling mistakes to spelling.txt 2017-10-03 17:54:23 -07:00
security Merge commit 'keys-fixes-20170927' into fixes-v4.14-rc3 2017-09-28 09:11:28 +10:00
sound vfs: constify path argument to kernel_read_file_from_path 2017-09-14 20:18:45 -07:00
tools Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-10-01 12:06:31 -07:00
usr ramfs: clarify help text that compression applies to ramfs as well as legacy ramdisk. 2017-07-06 16:24:30 -07:00
virt Revert "KVM: Don't accept obviously wrong gsi values via KVM_IRQFD" 2017-09-19 08:37:17 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Add hch to .get_maintainer.ignore 2015-08-21 14:30:10 -07:00
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore kbuild: Add support to generate LLVM assembly files 2017-04-25 08:13:52 +09:00
.mailmap power supply and reset changes for the v4.12 series (part 2) 2017-05-12 12:02:21 -07:00
COPYING
CREDITS selinux/stable-4.14 PR 20170831 2017-09-12 13:21:00 -07:00
Kbuild kbuild: Consolidate header generation from ASM offset information 2017-04-13 05:43:37 +09:00
Kconfig
MAINTAINERS LED fixes for 4.14-rc3 2017-09-29 19:33:32 -07:00
Makefile Linux 4.14-rc3 2017-10-01 14:54:54 -07:00
README README: add a new README file, pointing to the Documentation/ 2016-10-24 08:12:35 -02:00

Linux kernel
============

This file was moved to Documentation/admin-guide/README.rst

Please notice that there are several guides for kernel developers and users.
These guides can be rendered in a number of formats, like HTML and PDF.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.