Performance oriented customized Linux kernel based on the mainline kernel.
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Baolin Wang be2d575638 mm: change to return bool for folio_isolate_lru()
Patch series "Change the return value for page isolation functions", v3.

Now the page isolation functions did not return a boolean to indicate
success or not, instead it will return a negative error when failed
to isolate a page. So below code used in most places seem a boolean
success/failure thing, which can confuse people whether the isolation
is successful.

if (folio_isolate_lru(folio))
        continue;

Moreover the page isolation functions only return 0 or -EBUSY, and
most users did not care about the negative error except for few users,
thus we can convert all page isolation functions to return a boolean
value, which can remove the confusion to make code more clear.

No functional changes intended in this patch series.


This patch (of 4):

Now the folio_isolate_lru() did not return a boolean value to indicate
isolation success or not, however below code checking the return value can
make people think that it was a boolean success/failure thing, which makes
people easy to make mistakes (see the fix patch[1]).

if (folio_isolate_lru(folio))
	continue;

Thus it's better to check the negative error value expilictly returned by
folio_isolate_lru(), which makes code more clear per Linus's
suggestion[2].  Moreover Matthew suggested we can convert the isolation
functions to return a boolean[3], since most users did not care about the
negative error value, and can also remove the confusing of checking return
value.

So this patch converts the folio_isolate_lru() to return a boolean value,
which means return 'true' to indicate the folio isolation is successful,
and 'false' means a failure to isolation.  Meanwhile changing all users'
logic of checking the isolation state.

No functional changes intended.

[1] https://lore.kernel.org/all/20230131063206.28820-1-Kuan-Ying.Lee@mediatek.com/T/#u
[2] https://lore.kernel.org/all/CAHk-=wiBrY+O-4=2mrbVyxR+hOqfdJ=Do6xoucfJ9_5az01L4Q@mail.gmail.com/
[3] https://lore.kernel.org/all/Y+sTFqwMNAjDvxw3@casper.infradead.org/

Link: https://lkml.kernel.org/r/cover.1676424378.git.baolin.wang@linux.alibaba.com
Link: https://lkml.kernel.org/r/8a4e3679ed4196168efadf7ea36c038f2f7d5aa9.1676424378.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeelb@google.com>

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-20 12:46:17 -08:00
arch sh: initialize max_mapnr 2023-02-16 20:43:55 -08:00
block block: remove ->rw_page 2023-02-02 22:33:34 -08:00
certs certs: make system keyring depend on built-in x509 parser 2022-09-24 04:31:18 +09:00
crypto This update includes the following changes: 2022-12-14 12:31:09 -08:00
Documentation Docs/admin-guide/mm/damon/usage: add DAMON debugfs interface deprecation notice 2023-02-13 15:54:32 -08:00
drivers Merge branch 'mm-hotfixes-stable' into mm-stable 2023-02-10 15:34:48 -08:00
fs mm/hugetlb: convert hugetlb_add_to_page_cache to take in a folio 2023-02-13 15:54:29 -08:00
include mm: memcontrol: rename memcg_kmem_enabled() 2023-02-16 20:43:56 -08:00
init mm/page_ext: init page_ext early if there are no deferred struct pages 2023-02-02 22:33:22 -08:00
io_uring mm/nommu: factor out check for NOMMU shared mappings into is_nommu_shared_mapping() 2023-01-18 17:12:56 -08:00
ipc ipc/shm: introduce new do_vma_munmap() to munmap 2023-02-09 16:51:33 -08:00
kernel mm: replace vma->vm_flags direct modifications with modifier calls 2023-02-09 16:51:39 -08:00
lib maple_tree: reduce stack usage with gcc-9 and earlier 2023-02-16 20:43:55 -08:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm mm: change to return bool for folio_isolate_lru() 2023-02-20 12:46:17 -08:00
net mm: replace vma->vm_flags direct modifications with modifier calls 2023-02-09 16:51:39 -08:00
rust rust: types: add Opaque type 2022-12-04 01:59:16 +01:00
samples Char/Misc driver changes for 6.2-rc1 2022-12-16 03:49:24 -08:00
scripts scripts/gdb: fix 'lx-current' for x86 2023-02-09 15:56:51 -08:00
security mm: replace vma->vm_flags direct modifications with modifier calls 2023-02-09 16:51:39 -08:00
sound mm: replace vma->vm_flags direct modifications with modifier calls 2023-02-09 16:51:39 -08:00
tools objtool: add UACCESS exceptions for __tsan_volatile_read/write 2023-02-20 12:46:16 -08:00
usr usr/gen_init_cpio.c: remove unnecessary -1 values from int file 2022-10-03 14:21:44 -07:00
virt KVM: Ensure lockdep knows about kvm->lock vs. vcpu->mutex ordering rule 2023-01-11 13:32:21 -05:00
.clang-format iommufd for 6.2 2022-12-14 09:15:43 -08:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: ignore *.rpm 2022-12-30 17:22:14 +09:00
.mailmap mailmap: add entry for Alexander Mikhalitsyn 2023-02-03 17:52:24 -08:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: zram: zsmalloc: Add an additional co-maintainer 2022-12-15 16:37:49 -08:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS MAINTAINERS/DAMON: link maintainer profile, git trees, and website 2023-02-02 22:32:52 -08:00
Makefile Linux 6.2-rc4 2023-01-15 09:22:43 -06:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

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.