ACK/Cmt: [SRU][m/n][PATCH 0/2] arm64: TCP memory leak, slow network

[Thibault Ferrante]

On 24-05-2024 17:27, Philip Cox wrote:
> 
> BugLink: BugLink: https://bugs.launchpad.net/bugs/2045560
'Buglink:' is duplicated here, same in patchs, should be removed before applying.
> 
> 
> SRU Justification:
> 
> [Impact]
> There is a slow performance regression in the arm64 TCP code path. It appears to slowly leak memory as well.
> 
> This was caused to do amd64 and arm64 behaving differently in the codepaths and being IRQ safe.
> 
> The regression was introduced in kernel v6.0, and the fix is in v6.9.
> 
> 
> [Fix]
> The fix is to bring the arm64 behavior inline with the arm64 behavior, and remove the preempt_disable()/preempt_enable() pairs.
> 
> There are two patches required from the 6.8.y stable branch for this fix.   The two patches from the stable 6.8.y branch are:
> e830c804e267     net: make SK_MEMORY_PCPU_RESERV tunable
> d2fa3493811ec     net: fix sk_memory_allocated_{add|sub} vs softirqs
> 
> [Test Plan]
> I have tested this patch, as has AWS.
> 
> [Where problems could occur]
> Due to the differences of how irq preemption is being handled, future code may conflict with the new helpers introduced.
> 
> 
> --
> 
> 
> Adam Li (1):
>    net: make SK_MEMORY_PCPU_RESERV tunable
> 
> Eric Dumazet (1):
>    net: fix sk_memory_allocated_{add|sub} vs softirqs
> 
>   Documentation/admin-guide/sysctl/net.rst |  5 +++
>   include/net/sock.h                       | 39 +++++++++++++-----------
>   net/core/sock.c                          |  1 +
>   net/core/sysctl_net_core.c               |  9 ++++++
>   4 files changed, 36 insertions(+), 18 deletions(-)
> 

Acked-by: Thibault Ferrante <thibault.ferrante at canonical.com>

--
Thibault