linux/include
Eric Dumazet d4438ce68b inet: call inet6_ehashfn() once from inet6_hash_connect()
inet6_ehashfn() being called from __inet6_check_established()
has a big impact on performance, as shown in the Tested section.

After prior patch, we can compute the hash for port 0
from inet6_hash_connect(), and derive each hash in
__inet_hash_connect() from this initial hash:

hash(saddr, lport, daddr, dport) == hash(saddr, 0, daddr, dport) + lport

Apply the same principle for __inet_check_established(),
although inet_ehashfn() has a smaller cost.

Tested:

Server: ulimit -n 40000; neper/tcp_crr -T 200 -F 30000 -6 --nolog
Client: ulimit -n 40000; neper/tcp_crr -T 200 -F 30000 -6 --nolog -c -H server

Before this patch:

  utime_start=0.286131
  utime_end=4.378886
  stime_start=11.952556
  stime_end=1991.655533
  num_transactions=1446830
  latency_min=0.001061085
  latency_max=12.075275028
  latency_mean=0.376375302
  latency_stddev=1.361969596
  num_samples=306383
  throughput=151866.56

perf top:

 50.01%  [kernel]       [k] __inet6_check_established
 20.65%  [kernel]       [k] __inet_hash_connect
 15.81%  [kernel]       [k] inet6_ehashfn
  2.92%  [kernel]       [k] rcu_all_qs
  2.34%  [kernel]       [k] __cond_resched
  0.50%  [kernel]       [k] _raw_spin_lock
  0.34%  [kernel]       [k] sched_balance_trigger
  0.24%  [kernel]       [k] queued_spin_lock_slowpath

After this patch:

  utime_start=0.315047
  utime_end=9.257617
  stime_start=7.041489
  stime_end=1923.688387
  num_transactions=3057968
  latency_min=0.003041375
  latency_max=7.056589232
  latency_mean=0.141075048    # Better latency metrics
  latency_stddev=0.526900516
  num_samples=312996
  throughput=320677.21        # 111 % increase, and 229 % for the series

perf top: inet6_ehashfn is no longer seen.

 39.67%  [kernel]       [k] __inet_hash_connect
 37.06%  [kernel]       [k] __inet6_check_established
  4.79%  [kernel]       [k] rcu_all_qs
  3.82%  [kernel]       [k] __cond_resched
  1.76%  [kernel]       [k] sched_balance_domains
  0.82%  [kernel]       [k] _raw_spin_lock
  0.81%  [kernel]       [k] sched_balance_rq
  0.81%  [kernel]       [k] sched_balance_trigger
  0.76%  [kernel]       [k] queued_spin_lock_slowpath

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Tested-by: Jason Xing <kerneljasonxing@gmail.com>
Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Link: https://patch.msgid.link/20250305034550.879255-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
History 2025-03-06 15:26:02 -08:00
..
acpi LoongArch changes for v6.14 2025-01-28 08:52:01 -08:00
asm-generic arm64 fixes for -rc5 2025-03-01 13:44:51 -08:00
clocksource KVM/arm64 updates for 6.14 2025-01-28 09:01:36 -08:00
crypto crypto: skcipher - document skcipher_walk_done() and rename some vars 2025-01-14 11:38:32 +08:00
cxl cxl/events: Update Memory Module Event Record to CXL spec rev 3.1 2025-01-13 09:33:21 -07:00
drm drm: Fix DSC BPP increment decoding 2025-02-13 10:20:30 +02:00
dt-bindings dt-bindings: clock: qcom: Add CAMCC clocks for QCS8300 2025-02-02 20:59:04 -06:00
hyperv hyperv: Add new Hyper-V headers in include/hyperv 2025-01-10 00:54:20 +00:00
keys keys: drop shadowing dead prototype 2025-01-21 11:25:23 +02:00
kunit linux_kselftest-kunit-6.14-rc1 2025-01-22 12:32:39 -08:00
kvm Merge branch kvm-arm64/pkvm-memshare-declutter into kvmarm-master/next 2025-01-17 11:05:18 +00:00
linux Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2025-03-06 13:03:35 -08:00
math-emu powerpc/math-emu: Remove -w build flag and fix warnings 2022-09-05 17:28:25 +10:00
media media: cec: include linux/debugfs.h and linux/seq_file.h where needed 2025-01-07 12:21:38 +01:00
memory memory: renesas-rpc-if: Remove Runtime PM wrappers 2023-01-23 11:48:00 +01:00
misc cxl: fix typo in comment 2022-11-24 23:12:19 +11:00
net inet: call inet6_ehashfn() once from inet6_hash_connect() 2025-03-06 15:26:02 -08:00
pcmcia ARM: pxa/sa1100: move I/O space to PCI_IOBASE 2022-05-07 22:56:17 +02:00
ras mm/memory-failure: remove obsolete MF_MSG_DIFFERENT_COMPOUND 2024-07-12 15:52:22 -07:00
rdma RDMA/core: Support link status events dispatching 2024-12-24 05:22:18 -05:00
rv rv: Reset per-task monitors also for idle tasks 2025-01-23 12:16:04 -05:00
scsi Driver core and debugfs updates 2025-01-28 12:25:12 -08:00
soc soc: driver updates for 6.14 2025-01-24 14:56:59 -08:00
sound ASoC: cs35l56: Prevent races when soft-resetting using SPI control 2025-02-25 15:06:58 +00:00
target scsi: target: iscsi: switch to using the crc32c library 2024-12-01 17:23:02 -08:00
trace Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2025-02-27 10:20:58 -08:00
uapi First 6.15 material: 2025-03-04 08:50:42 -08:00
ufs scsi: ufs: core: Fix use-after free in init error and remove paths 2025-02-03 17:20:01 -05:00
vdso vdso: Correct typo in PAGE_SHIFT comment 2025-01-15 11:07:08 +01:00
video - Improved handling of LCD power states and interactions with the fbdev subsystem. 2024-11-22 16:29:57 -08:00
xen xen: Remove dependency between pciback and privcmd 2024-10-18 11:59:04 +02:00