No description
  • C 96.8%
  • Assembly 0.9%
  • Rust 0.7%
  • Shell 0.6%
  • Python 0.5%
  • Other 0.3%
Find a file
Lucas Stach 0fd304a885 mm: page_alloc: control latency caused by zone PCP draining
[ Upstream commit 55f77df7d7 ]

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>
Stable-dep-of: 66eca1021a ("mm/page_alloc: fix pcp->count race between drain_pages_zone() vs __rmqueue_pcplist()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
History 2024-08-11 12:35:53 +02:00
arch arm64: dts: qcom: ipq8074: Disable SS instance in Parkmode for USB 2024-08-11 12:35:51 +02:00
block block: initialize integrity buffer to zero before writing it to media 2024-08-03 08:48:53 +02:00
certs certs: Fix build error when PKCS#11 URI contains semicolon 2023-02-09 11:28:11 +01:00
crypto crypto: aead,cipher - zeroize key buffer after use 2024-07-11 12:47:05 +02:00
Documentation dt-bindings: thermal: correct thermal zone node name limit 2024-08-03 08:49:30 +02:00
drivers leds: triggers: Flush pending brightness before activating trigger 2024-08-11 12:35:53 +02:00
fs ext4: check the extent status again before inserting delalloc block 2024-08-11 12:35:52 +02:00
include leds: trigger: Store brightness set by led_trigger_event() 2024-08-11 12:35:53 +02:00
init smp: Provide 'setup_max_cpus' definition on UP too 2024-06-16 13:41:42 +02:00
io_uring io_uring: fix io_match_task must_hold 2024-08-03 08:49:53 +02:00
ipc sysctl: treewide: drop unused argument ctl_table_root::set_ownership(table) 2024-08-11 12:35:51 +02:00
kernel bpf, events: Use prog to emit ksymbol event for main program 2024-08-03 08:49:49 +02:00
lib kobject_uevent: Fix OOB access within zap_modalias_env() 2024-08-03 08:49:39 +02:00
LICENSES LICENSES/LGPL-2.1: Add LGPL-2.1-or-later as valid identifiers 2021-12-16 14:33:10 +01:00
mm mm: page_alloc: control latency caused by zone PCP draining 2024-08-11 12:35:53 +02:00
net sysctl: treewide: drop unused argument ctl_table_root::set_ownership(table) 2024-08-11 12:35:51 +02:00
rust rust: macros: fix soundness issue in module! macro 2024-05-17 11:56:17 +02:00
samples work around gcc bugs with 'asm goto' with outputs 2024-02-23 09:12:28 +01:00
scripts kbuild: avoid build error when single DTB is turned into composite DTB 2024-08-03 08:49:48 +02:00
security apparmor: Fix null pointer deref when receiving skb during sock creation 2024-08-03 08:49:50 +02:00
sound ASoC: Intel: use soc_intel_is_byt_cr() only when IOSF_MBI is reachable 2024-08-03 08:49:52 +02:00
tools tools/resolve_btfids: Fix comparison of distinct pointer types warning in resolve_btfids 2024-08-03 08:49:49 +02:00
usr usr/gen_init_cpio.c: remove unnecessary -1 values from int file 2022-10-03 14:21:44 -07:00
virt KVM: Fix a data race on last_boosted_vcpu in kvm_vcpu_on_spin() 2024-06-27 13:46:21 +02:00
.clang-format inet: ping: use hlist_nulls rcu iterator during lookup 2022-12-01 12:42:46 +01:00
.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 Kbuild: add Rust support 2022-09-28 09:02:20 +02:00
.mailmap 9 hotfixes. 6 for MM, 3 for other areas. Four of these patches address 2022-12-10 17:10:52 -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: Remove Michal Marek from Kbuild maintainers 2022-11-16 14:53:00 +09:00
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: add leah to 6.1 MAINTAINERS file 2024-05-17 11:56:16 +02:00
Makefile Linux 6.1.103 2024-08-03 08:49:53 +02:00
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.