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Lucas Stach 55f77df7d7 mm: page_alloc: control latency caused by zone PCP draining
Patch series "mm/treewide: Remove pXd_huge() API", v2.

In previous work [1], we removed the pXd_large() API, which is arch
specific.  This patchset further removes the hugetlb pXd_huge() API.

Hugetlb was never special on creating huge mappings when compared with
other huge mappings.  Having a standalone API just to detect such pgtable
entries is more or less redundant, especially after the pXd_leaf() API set
is introduced with/without CONFIG_HUGETLB_PAGE.

When looking at this problem, a few issues are also exposed that we don't
have a clear definition of the *_huge() variance API.  This patchset
started by cleaning these issues first, then replace all *_huge() users to
use *_leaf(), then drop all *_huge() code.

On x86/sparc, swap entries will be reported "true" in pXd_huge(), while
for all the rest archs they're reported "false" instead.  This part is
done in patch 1-5, in which I suspect patch 1 can be seen as a bug fix,
but I'll leave that to hmm experts to decide.

Besides, there are three archs (arm, arm64, powerpc) that have slightly
different definitions between the *_huge() v.s.  *_leaf() variances.  I
tackled them separately so that it'll be easier for arch experts to chim
in when necessary.  This part is done in patch 6-9.

The final patches 10-14 do the rest on the final removal, since *_leaf()
will be the ultimate API in the future, and we seem to have quite some
confusions on how *_huge() APIs can be defined, provide a rich comment for
*_leaf() API set to define them properly to avoid future misuse, and
hopefully that'll also help new archs to start support huge mappings and
avoid traps (like either swap entries, or PROT_NONE entry checks).

[1] https://lore.kernel.org/r/20240305043750.93762-1-peterx@redhat.com


This patch (of 14):

When the complete PCP is drained a much larger number of pages than the
usual batch size might be freed at once, causing large IRQ and preemption
latency spikes, as they are all freed while holding the pcp and zone
spinlocks.

To avoid those latency spikes, limit the number of pages freed in a single
bulk operation to common batch limits.

Link: https://lkml.kernel.org/r/20240318200404.448346-1-peterx@redhat.com
Link: https://lkml.kernel.org/r/20240318200736.2835502-1-l.stach@pengutronix.de
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Peter Xu <peterx@redhat.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bjorn Andersson <andersson@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Fabio Estevam <festevam@denx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Konrad Dybcio <konrad.dybcio@linaro.org>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-04-25 20:55:44 -07:00
arch Misc x86 fixes: 2024-04-14 10:48:51 -07:00
block block-6.9-20240412 2024-04-12 10:22:33 -07:00
certs This update includes the following changes: 2023-11-02 16:15:30 -10:00
crypto This push fixes a regression that broke iwd as well as a divide by 2024-03-25 10:48:23 -07:00
Documentation mm,page_owner: fix refcount imbalance 2024-04-16 15:39:49 -07:00
drivers Fix a bug in the GIC irqchip driver. 2024-04-14 10:12:34 -07:00
fs mm: support page_mapcount() on page_has_type() pages 2024-04-24 19:34:26 -07:00
include mm: memcg: add NULL check to obj_cgroup_put() 2024-04-25 20:55:43 -07:00
init fs/proc: Skip bootloader comment if no embedded kernel parameters 2024-04-09 23:36:18 +09:00
io_uring io_uring/net: restore msg_control on sendzc retry 2024-04-08 21:48:41 -06:00
ipc sysctl changes for v6.9-rc1 2024-03-18 14:59:13 -07:00
kernel mm: memcg: add NULL check to obj_cgroup_put() 2024-04-25 20:55:43 -07:00
lib stackdepot: respect __GFP_NOLOCKDEP allocation flag 2024-04-24 19:34:26 -07:00
LICENSES
mm mm: page_alloc: control latency caused by zone PCP draining 2024-04-25 20:55:44 -07:00
net Including fixes from bluetooth. 2024-04-11 11:46:31 -07:00
rust Kbuild updates for v6.9 2024-03-21 14:41:00 -07:00
samples Tracing updates for 6.9: 2024-03-18 15:11:44 -07:00
scripts hardening fixes for v6.9-rc4 2024-04-10 13:31:34 -07:00
security security: Place security_path_post_mknod() where the original IMA call was 2024-04-03 10:21:32 -07:00
sound ASoC: Fixes for v6.9 2024-04-05 08:48:12 +02:00
tools selftests/mm: virtual_address_range: Switch to ksft_exit_fail_msg 2024-04-25 20:55:43 -07:00
usr Kbuild updates for v6.8 2024-01-18 17:57:07 -08:00
virt KVM Xen and pfncache changes for 6.9: 2024-03-11 10:42:55 -04:00
.clang-format clang-format: Update with v6.7-rc4's for_each macro list 2023-12-08 23:54:38 +01:00
.cocciconfig
.editorconfig Add .editorconfig file for basic formatting 2023-12-28 16:22:47 +09:00
.get_maintainer.ignore Add Jeff Kirsher to .get_maintainer.ignore 2024-03-08 11:36:54 +00:00
.gitattributes
.gitignore kbuild: create a list of all built DTB files 2024-02-19 18:20:39 +09:00
.mailmap MAINTAINERS: update Naoya Horiguchi's email address 2024-04-16 15:39:51 -07:00
.rustfmt.toml
COPYING
CREDITS MAINTAINERS: Drop Gustavo Pimentel as PCI DWC Maintainer 2024-03-27 13:41:02 -05:00
Kbuild
Kconfig
MAINTAINERS MAINTAINERS: update Naoya Horiguchi's email address 2024-04-16 15:39:51 -07:00
Makefile Linux 6.9-rc4 2024-04-14 13:38:39 -07:00
README README: Fix spelling 2024-03-18 03:36:32 -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 reStructuredText 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.