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David S. Miller ac60031f79 Merge branch 'udp-4tuple-hash'
Philo Lu says:

====================
udp: Add 4-tuple hash for connected sockets

This patchset introduces 4-tuple hash for connected udp sockets, to make
connected udp lookup faster.

Stress test results (with 1 cpu fully used) are shown below, in pps:
(1) _un-connected_ socket as server
    [a] w/o hash4: 1,825176
    [b] w/  hash4: 1,831750 (+0.36%)

(2) 500 _connected_ sockets as server
    [c] w/o hash4:   290860 (only 16% of [a])
    [d] w/  hash4: 1,889658 (+3.1% compared with [b])
With hash4, compute_score is skipped when lookup, so [d] is slightly
better than [b].

Patch1: Add a new counter for hslot2 named hash4_cnt, to avoid cache line
        miss when lookup.
Patch2: Add hslot/hlist_nulls for 4-tuple hash.
Patch3 and 4: Implement 4-tuple hash for ipv4 and ipv6.

The detailed motivation is described in Patch 3.

The 4-tuple hash increases the size of udp_sock and udp_hslot. Thus add it
with CONFIG_BASE_SMALL, i.e., it's a no op with CONFIG_BASE_SMALL.

Intentionally, the feature is not available for udplite. Though udplite
shares some structs and functions with udp, its connect() keeps unchanged.
So all udplite sockets perform the same as un-connected udp sockets.
Besides, udplite also shares the additional memory consumption in udp_sock
and udptable.

changelogs:
v8 -> v9 (Paolo Abeni):
- Add explanation about udplite in cover letter
- Update tags for co-developers
- Add acked-by tags of Paolo and Willem

v7 -> v8:
- add EXPORT_SYMBOL for ipv6.ko build

v6 -> v7 (Kuniyuki Iwashima):
- export udp_ehashfn to be used by udpv6 rehash

v5 -> v6 (Paolo Abeni):
- move udp_table_hash4_init from patch2 to patch1
- use hlist_nulls for lookup-rehash race
- add test results in commit log
- add more comment, e.g., for rehash4 used in hash4
- add ipv6 support (Patch4), and refactor some functions for better
  sharing, without functionality change

v4 -> v5 (Paolo Abeni):
- add CONFIG_BASE_SMALL with which udp hash4 does nothing

v3 -> v4 (Willem de Bruijn):
- fix mistakes in udp_pernet_table_alloc()

RFCv2 -> v3 (Gur Stavi):
- minor fix in udp_hashslot2() and udp_table_init()
- add rcu sync in rehash4()

RFCv1 -> RFCv2:
- add a new struct for hslot2
- remove the sockopt UDP_HASH4 because it has little side effect for
  unconnected sockets
- add rehash in connect()
- re-organize the patch into 3 smaller ones
- other minor fix

v8:
https://lore.kernel.org/all/20241108054836.123484-1-lulie@linux.alibaba.com/
v7:
https://lore.kernel.org/all/20241105121225.12513-1-lulie@linux.alibaba.com/
v6:
https://lore.kernel.org/all/20241031124550.20227-1-lulie@linux.alibaba.com/
v5:
https://lore.kernel.org/all/20241018114535.35712-1-lulie@linux.alibaba.com/
v4:
https://lore.kernel.org/all/20241012012918.70888-1-lulie@linux.alibaba.com/
v3:
https://lore.kernel.org/all/20241010090351.79698-1-lulie@linux.alibaba.com/
RFCv2:
https://lore.kernel.org/all/20240924110414.52618-1-lulie@linux.alibaba.com/
RFCv1:
https://lore.kernel.org/all/20240913100941.8565-1-lulie@linux.alibaba.com/
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2024-11-18 11:56:21 +00:00
arch Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-11-14 11:29:15 -08:00
block block-6.12-20241101 2024-11-01 13:41:55 -10:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto This push fixes the following issues: 2024-10-16 08:42:54 -07:00
Documentation dt-bindings: net: dsa: microchip,ksz: Drop undocumented "id" 2024-11-15 14:29:28 -08:00
drivers virtio_net: xdp_features add NETDEV_XDP_ACT_XSK_ZEROCOPY 2024-11-15 18:46:56 -08:00
fs Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-11-14 11:29:15 -08:00
include ipv6/udp: Add 4-tuple hash for connected socket 2024-11-18 11:56:21 +00:00
init cfi: fix conditions for HAVE_CFI_ICALL_NORMALIZE_INTEGERS 2024-10-13 22:23:13 +02:00
io_uring io_uring/rw: fix missing NOWAIT check for O_DIRECT start write 2024-10-31 08:21:02 -06:00
ipc struct fd layout change (and conversion to accessor helpers) 2024-09-23 09:35:36 -07:00
kernel Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-11-14 11:29:15 -08:00
lib Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-11-14 11:29:15 -08:00
LICENSES LICENSES: add 0BSD license text 2024-09-01 20:43:24 -07:00
mm Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-11-14 11:29:15 -08:00
net ipv6/udp: Add 4-tuple hash for connected socket 2024-11-18 11:56:21 +00:00
rust Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-10-21 09:14:18 +02:00
samples Including fixes from bluetooth. 2024-11-14 10:05:33 -08:00
scripts Kbuild fixes for v6.12 (2nd) 2024-11-03 08:29:02 -10:00
security integrity-v6.12 2024-11-12 13:06:31 -08:00
sound ASoC: Fixes for v6.12 2024-11-08 09:25:33 +01:00
tools selftests: net: fdb_notify: Add a test for FDB notifications 2024-11-15 16:39:19 -08:00
usr initramfs: shorten cmd_initfs in usr/Makefile 2024-07-16 01:07:52 +09:00
virt ARM64: 2024-10-21 11:22:04 -07:00
.clang-format clang-format: Update with v6.11-rc1's for_each macro list 2024-08-02 13:20:31 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore Add Jeff Kirsher to .get_maintainer.ignore 2024-03-08 11:36:54 +00:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore Kbuild updates for v6.12 2024-09-24 13:02:06 -07:00
.mailmap mailmap: add entry for Thorsten Blum 2024-11-07 14:14:59 -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 self from DSA entry 2024-11-03 12:52:38 -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 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-11-14 11:29:15 -08:00
Makefile Linux 6.12-rc7 2024-11-10 14:19:35 -08:00
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.