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Subject: Re: [PATCH v9 4/8] kallsyms: introduce sections needed to map symbols
 to built-in modules
To:     Nick Alcock <nick.alcock@oracle.com>,
        Luis Chamberlain <mcgrof@kernel.org>
CC:     <masahiroy@kernel.org>, <linux-modules@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <arnd@arndb.de>,
        <akpm@linux-foundation.org>, <eugene.loh@oracle.com>,
        <kris.van.hees@oracle.com>, Steven Rostedt <rostedt@goodmis.org>
References: <20221109134132.9052-1-nick.alcock@oracle.com>
 <20221109134132.9052-5-nick.alcock@oracle.com>
 <Y3BhRvt53xO5A0iQ@bombadil.infradead.org> <87mt8tv554.fsf@esperi.org.uk>
From:   "Leizhen (ThunderTown)" <thunder.leizhen@huawei.com>
Message-ID: <76d7ba29-c7d2-d082-5928-599844112494@huawei.com>
Date:   Tue, 15 Nov 2022 19:47:27 +0800
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On 2022/11/15 1:04, Nick Alcock wrote:
> On 13 Nov 2022, Luis Chamberlain outgrape:
> 
>> On Wed, Nov 09, 2022 at 01:41:28PM +0000, Nick Alcock wrote:
>>> The mapping consists of three new symbols
>>
>> The entire commit log does not describe *why*.
> 
> ... because it's in the other commit logs and the cover letter. I can
> repeat the motivation in this log too if you like.
> 
>> Can I also trouble you to rebase on top of modules-next [0]
> 
> Sure!
> 
>> Does the kallsyms loop more than 3 times now with Zhen Lei's work and
>> your new symbols on top on a allyesconfig build?
> 
> I don't understand the question, sorry. If this is about the number of
> KALLSYMS invocations in the kernel build, that should be unchanged by
> this patch. This was an explicit design goal because it's quite slow to
> run kallsyms more times and I was already feeling guilty about having to
> bring back the tristate recursion.
> 
> I haven't tried it with Zhen Lei's work: will try for the next
> iteration, as a matter of course after the rebase. (And, looking at the
> patch series at the top of modules-next, wow is that quite a hefty
> performance improvement. And a hefty memory usage increase :( I have a
> horrible feeling that one of my machines won't have enough memory to
> boot after this goes in, but it was terribly outdated anyway.)

It's only about 500K. It shouldn't be a problem. Your machine boot from flash?

> .
> 

-- 
Regards,
  Zhen Lei