Re: [PATCH v8 7/9] livepatch: Improve the search performance of module_kallsyms_on_each_symbol()

From: Leizhen (ThunderTown)
Date: Wed Nov 23 2022 - 21:41:54 EST




On 2022/11/23 21:57, Petr Mladek wrote:
> On Wed 2022-11-02 16:49:19, Zhen Lei wrote:
>> Currently we traverse all symbols of all modules to find the specified
>> function for the specified module. But in reality, we just need to find
>> the given module and then traverse all the symbols in it.
>>
>> Let's add a new parameter 'const char *modname' to function
>> module_kallsyms_on_each_symbol(), then we can compare the module names
>> directly in this function and call hook 'fn' after matching. And the
>> parameter 'struct module *' in the hook 'fn' can also be deleted.
>>
>> Phase1: mod1-->mod2..(subsequent modules do not need to be compared)
>> |
>> Phase2: -->f1-->f2-->f3
>
> Just for record. The patch looks good from the livepatching code POV.
>
> But I guess that it will need to get updated to support the new
> callers in the ftrace and bpf code.

Yes, this patch and 8/9 conflicts with the patch series of Jiri Olsa,
So they didn't merge into linux-next. I will update and repost after
v6.2-rc1.

>
> Best Regards,
> Petr
> .
>

--
Regards,
Zhen Lei