Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-10 14:11:52 +00:00
Code Issues Packages Projects Releases Wiki Activity
A mirror of the official Linux kernel repository just in case
968,911 Commits 7 Branches 860 Tags 6.5 GiB
C 97.6%
Assembly 1%
Shell 0.5%
Python 0.3%
Makefile 0.3%
a4efc174b3
Go to file
Lecopzer Chen a4efc174b3 mm/cma.c: remove redundant cma_mutex lock 
The cma_mutex which protects alloc_contig_range() was first appeared in
commit 7ee793a62f ("cma: Remove potential deadlock situation"), at that
time, there is no guarantee the behavior of concurrency inside
alloc_contig_range().

After commit 2c7452a075 ("mm/page_isolation.c: make
start_isolate_page_range() fail if already isolated")

  > However, two subsystems (CMA and gigantic
  > huge pages for example) could attempt operations on the same range.  If
  > this happens, one thread may 'undo' the work another thread is doing.
  > This can result in pageblocks being incorrectly left marked as
  > MIGRATE_ISOLATE and therefore not available for page allocation.

The concurrency inside alloc_contig_range() was clarified.

Now we can find that hugepage and virtio call alloc_contig_range() without
any lock, thus cma_mutex is "redundant" in cma_alloc() now.

Link: https://lkml.kernel.org/r/20201020102241.3729-1-lecopzer.chen@mediatek.com
Signed-off-by: Lecopzer Chen <lecopzer.chen@mediatek.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: YJ Chiang <yj.chiang@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15 12:13:46 -08:00
arch arch, mm: make kernel_page_present() always available 2020-12-15 12:13:43 -08:00
block block-5.10-2020-12-05 2020-12-05 14:45:30 -08:00
certs .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
crypto drivers-5.10-2020-10-12 2020-10-13 13:04:41 -07:00
Documentation arm: remove CONFIG_ARCH_HAS_HOLES_MEMORYMODEL 2020-12-15 12:13:42 -08:00
drivers lkdtm: disable KASAN for rodata.o 2020-12-15 12:13:42 -08:00
fs arm: remove CONFIG_ARCH_HAS_HOLES_MEMORYMODEL 2020-12-15 12:13:42 -08:00
include mm: migrate: clean up migrate_prep{_local} 2020-12-15 12:13:45 -08:00
init init/main: fix broken buffer_init when DEFERRED_STRUCT_PAGE_INIT set 2020-12-15 12:13:44 -08:00
ipc vm_ops: rename .split() callback to .may_split() 2020-12-15 12:13:41 -08:00
kernel PM: hibernate: make direct map manipulations more explicit 2020-12-15 12:13:43 -08:00
lib lib/test_kasan.c: add workqueue test case 2020-12-15 12:13:42 -08:00
LICENSES LICENSES/deprecated: add Zlib license text 2020-09-16 14:33:49 +02:00
mm mm/cma.c: remove redundant cma_mutex lock 2020-12-15 12:13:46 -08:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2020-12-10 14:29:30 -08:00
samples Tracing fixes for 5.10-rc6 2020-12-01 15:30:18 -08:00
scripts Kbuild fixes for v5.10 (2nd) 2020-12-06 10:31:39 -08:00
security selinux/stable-5.10 PR 20201113 2020-11-14 12:04:02 -08:00
sound ALSA: pcm: use krealloc_array() 2020-12-15 12:13:37 -08:00
tools kselftests: vm: add mremap tests 2020-12-15 12:13:40 -08:00
usr Merge branch 'work.fdpic' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-08-07 13:29:39 -07:00
virt kvm: x86/mmu: Support dirty logging for the TDP MMU 2020-10-23 03:42:13 -04:00
.clang-format RDMA 5.10 pull request 2020-10-17 11:18:18 -07:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: docs: ignore sphinx_*/ directories 2020-09-10 10:44:31 -06:00
.mailmap mailmap: add two more addresses of Uwe Kleine-König 2020-12-06 10:19:07 -08:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Jason Cooper to CREDITS 2020-11-30 10:20:34 +01:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-12-10 15:30:13 -08:00
Makefile Linux 5.10 2020-12-13 14:41:30 -08:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

README 

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

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

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.