Re: 回复: [PATCH net-next v5 1/1] net:openvswitch:reduce cpu_used_mask memory

Jiri Pirko
2023-02-03T11:55:33Z

Fri, Feb 03, 2023 at 10:03:28AM CET, taoyuan_eddy@hotmail.com wrote:
>sorry, Jiri, my bad, will hold on before the next submission/hope it is the final one

Don't top-post please. So what is the change comparing to v4?

>
>eddy
>________________________________
>发件人: Jiri Pirko <jiri@resnulli.us>
>发送时间: 2023年2月3日 9:00
>收件人: Eddy Tao <taoyuan_eddy@hotmail.com>
>抄送: netdev@vger.kernel.org <netdev@vger.kernel.org>; Pravin B Shelar <pshelar@ovn.org>; David S. Miller <davem@davemloft.net>; Eric Dumazet <edumazet@google.com>; Jakub Kicinski <kuba@kernel.org>; Paolo Abeni <pabeni@redhat.com>; dev@openvswitch.org <dev@openvswitch.org>; linux-kernel@vger.kernel.org <linux-kernel@vger.kernel.org>
>主题: Re: [PATCH net-next v5 1/1] net:openvswitch:reduce cpu_used_mask memory
>
>Fri, Feb 03, 2023 at 09:52:56AM CET, taoyuan_eddy@hotmail.com wrote:
>>Use actual CPU number instead of hardcoded value to decide the size
>>of 'cpu_used_mask' in 'struct sw_flow'. Below is the reason.
>>
>>'struct cpumask cpu_used_mask' is embedded in struct sw_flow.
>>Its size is hardcoded to CONFIG_NR_CPUS bits, which can be
>>8192 by default, it costs memory and slows down ovs_flow_alloc
>>
>>To address this, redefine cpu_used_mask to pointer
>>append cpumask_size() bytes after 'stat' to hold cpumask
>>
>>cpumask APIs like cpumask_next and cpumask_set_cpu never access
>>bits beyond cpu count, cpumask_size() bytes of memory is enough
>>
>>Signed-off-by: Eddy Tao <taoyuan_eddy@hotmail.com>
>
>Eddy, could you please slow down a bit? Why did you send v5 right
>after v4? Could you please always put a changelog to the patch
>submitted to contain info about changes in between the
>submitted version?
>
>Thanks!
>