linux/include
Kuniyuki Iwashima afd20b9290 af_unix: Replace the big lock with small locks.
The hash table of AF_UNIX sockets is protected by the single lock.  This
patch replaces it with per-hash locks.

The effect is noticeable when we handle multiple sockets simultaneously.
Here is a test result on an EC2 c5.24xlarge instance.  It shows latency
(under 10us only) in unix_insert_unbound_socket() while 64 CPUs creating
1024 sockets for each in parallel.

  Without this patch:

     nsec          : count     distribution
        0          : 179      |                                        |
        500        : 3021     |*********                               |
        1000       : 6271     |*******************                     |
        1500       : 6318     |*******************                     |
        2000       : 5828     |*****************                       |
        2500       : 5124     |***************                         |
        3000       : 4426     |*************                           |
        3500       : 3672     |***********                             |
        4000       : 3138     |*********                               |
        4500       : 2811     |********                                |
        5000       : 2384     |*******                                 |
        5500       : 2023     |******                                  |
        6000       : 1954     |*****                                   |
        6500       : 1737     |*****                                   |
        7000       : 1749     |*****                                   |
        7500       : 1520     |****                                    |
        8000       : 1469     |****                                    |
        8500       : 1394     |****                                    |
        9000       : 1232     |***                                     |
        9500       : 1138     |***                                     |
        10000      : 994      |***                                     |

  With this patch:

     nsec          : count     distribution
        0          : 1634     |****                                    |
        500        : 13170    |****************************************|
        1000       : 13156    |*************************************** |
        1500       : 9010     |***************************             |
        2000       : 6363     |*******************                     |
        2500       : 4443     |*************                           |
        3000       : 3240     |*********                               |
        3500       : 2549     |*******                                 |
        4000       : 1872     |*****                                   |
        4500       : 1504     |****                                    |
        5000       : 1247     |***                                     |
        5500       : 1035     |***                                     |
        6000       : 889      |**                                      |
        6500       : 744      |**                                      |
        7000       : 634      |*                                       |
        7500       : 498      |*                                       |
        8000       : 433      |*                                       |
        8500       : 355      |*                                       |
        9000       : 336      |*                                       |
        9500       : 284      |                                        |
        10000      : 243      |                                        |

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-26 18:01:58 -08:00
..
acpi Merge branches 'acpica', 'acpi-ec', 'acpi-pmic' and 'acpi-video' 2021-11-10 14:03:14 +01:00
asm-generic Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-11-26 13:45:19 -08:00
clocksource ARM: 2021-11-02 11:24:14 -07:00
crypto
drm Removed the TTM Huge Page functionnality to address a crash, a timeout 2021-11-11 08:14:19 +10:00
dt-bindings dt-bindings: Rename Ingenic CGU headers to ingenic,*.h 2021-11-11 22:27:14 -06:00
keys
kunit include/kunit/test.h: replace kernel.h with the necessary inclusions 2021-11-09 10:02:49 -08:00
kvm
linux Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-11-26 13:45:19 -08:00
math-emu
media Merge branch 'akpm' (patches from Andrew) 2021-11-09 10:11:53 -08:00
memory
misc
net af_unix: Replace the big lock with small locks. 2021-11-26 18:01:58 -08:00
pcmcia
ras
rdma RDMA/netlink: Add __maybe_unused to static inline in C file 2021-11-16 13:13:08 -04:00
scsi SCSI misc on 20211112 2021-11-12 12:25:50 -08:00
soc Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-11-26 13:45:19 -08:00
sound Revert "ALSA: memalloc: Convert x86 SG-buffer handling with non-contiguous type" 2021-11-04 22:10:03 +01:00
target
trace f2fs-for-5.16-rc1 2021-11-13 11:20:22 -08:00
uapi mctp: Add MCTP-over-serial transport binding 2021-11-23 11:47:51 +00:00
vdso
video
xen xen: add "not_essential" flag to struct xenbus_driver 2021-11-23 13:41:29 -06:00