Go to file
Zi Yan 1e6440eb42 mm/numa: no task_numa_fault() call if PMD is changed
commit fd8c35a929 upstream.

When handling a numa page fault, task_numa_fault() should be called by a
process that restores the page table of the faulted folio to avoid
duplicated stats counting.  Commit c5b5a3dd2c ("mm: thp: refactor NUMA
fault handling") restructured do_huge_pmd_numa_page() and did not avoid
task_numa_fault() call in the second page table check after a numa
migration failure.  Fix it by making all !pmd_same() return immediately.

This issue can cause task_numa_fault() being called more than necessary
and lead to unexpected numa balancing results (It is hard to tell whether
the issue will cause positive or negative performance impact due to
duplicated numa fault counting).

Link: https://lkml.kernel.org/r/20240809145906.1513458-3-ziy@nvidia.com
Fixes: c5b5a3dd2c ("mm: thp: refactor NUMA fault handling")
Reported-by: "Huang, Ying" <ying.huang@intel.com>
Closes: https://lore.kernel.org/linux-mm/87zfqfw0yw.fsf@yhuang6-desk2.ccr.corp.intel.com/
Signed-off-by: Zi Yan <ziy@nvidia.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Yang Shi <shy828301@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-09-04 13:23:36 +02:00
arch KVM: arm64: Make ICC_*SGI*_EL1 undef in the absence of a vGICv3 2024-09-04 13:23:36 +02:00
block block: initialize integrity buffer to zero before writing it to media 2024-08-19 05:44:50 +02:00
certs certs/blacklist_hashes.c: fix const confusion in certs blacklist 2022-06-22 14:22:01 +02:00
crypto crypto: aead,cipher - zeroize key buffer after use 2024-07-18 13:07:27 +02:00
Documentation arm64: cpufeature: Fix the visibility of compat hwcaps 2024-08-19 05:45:51 +02:00
drivers hwmon: (ltc2992) Fix memory leak in ltc2992_parse_dt() 2024-09-04 13:23:36 +02:00
fs nfsd: make svc_stat per-network namespace instead of global 2024-09-04 13:23:31 +02:00
include scsi: core: Fix the return value of scsi_logical_block_count() 2024-09-04 13:23:35 +02:00
init init/main.c: Fix potential static_command_line memory overflow 2024-04-27 17:05:28 +02:00
io_uring io_uring/io-wq: limit retrying worker initialisation 2024-08-19 05:45:22 +02:00
ipc ipc/sem: Fix dangling sem_array access in semtimedop race 2022-12-08 11:28:45 +01:00
kernel hrtimer: Prevent queuing of hrtimer without a function callback 2024-09-04 13:23:28 +02:00
lib bitmap: introduce generic optimized bitmap_size() 2024-09-04 13:23:16 +02:00
LICENSES LICENSES/dual/CC-BY-4.0: Git rid of "smart quotes" 2021-07-15 06:31:24 -06:00
mm mm/numa: no task_numa_fault() call if PMD is changed 2024-09-04 13:23:36 +02:00
net Bluetooth: MGMT: Add error handling to pair_device() 2024-09-04 13:23:35 +02:00
samples Add gitignore file for samples/fanotify/ subdirectory 2024-07-27 10:46:16 +02:00
scripts kbuild: Fix '-S -c' in x86 stack protector scripts 2024-08-19 05:45:16 +02:00
security selinux: fix potential counting error in avc_add_xperms_decision() 2024-09-04 13:23:17 +02:00
sound ALSA: timer: Relax start tick time check for slave timer elements 2024-09-04 13:23:36 +02:00
tools tc-testing: don't access non-existent variable on exception 2024-09-04 13:23:32 +02:00
usr usr/include/Makefile: add linux/nfc.h to the compile-test coverage 2022-02-01 17:27:15 +01:00
virt KVM: Always flush async #PF workqueue when vCPU is being destroyed 2024-04-10 16:18:34 +02:00
.clang-format clang-format: Update with the latest for_each macro list 2021-05-12 23:32:39 +02:00
.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: ignore only top-level modules.builtin 2021-05-02 00:43:35 +09:00
.mailmap mailmap: add Andrej Shadura 2021-10-18 20:22:03 -10:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Daniel Drake to credits 2021-09-21 08:34:58 +03:00
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 trace: Relocate event helper files 2024-04-10 16:19:24 +02:00
Makefile Linux 5.15.165 2024-08-19 05:45:52 +02:00
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.