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Subject: Re: [PATCH v2] kmemleak: Turn kmemleak_lock to raw spinlock on RT
To:     Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        Catalin Marinas <catalin.marinas@arm.com>
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        <linux-kernel@vger.kernel.org>, <linux-rt-users@vger.kernel.org>
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From:   He Zhe <zhe.he@windriver.com>
Message-ID: <b967b22a-78a9-5b73-9b04-26085f796e5d@windriver.com>
Date:   Thu, 20 Dec 2018 09:46:34 +0800
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On 2018/12/19 23:30, Sebastian Andrzej Siewior wrote:
> On 2018-12-18 15:07:45 [+0000], Catalin Marinas wrote:
> …
>> It may be worth running some performance/latency tests during kmemleak
>> scanning (echo scan > /sys/kernel/debug/kmemleak) but at a quick look,
>> I don't think we'd see any difference with a raw_spin_lock_t.
>>
>> With a bit more thinking (though I'll be off until the new year), we
>> could probably get rid of the kmemleak_lock entirely in scan_block() and
>> make lookup_object() and the related rbtree code in kmemleak RCU-safe.
> Okay. So let me apply that patch into my RT tree with your ack (from the
> other email). And then I hope that it either shows up upstream or gets
> replaced with RCU in the ende :)

I'd like to do the upstreaming or replacing. Thanks.

Zhe

>
> Thanks.
>
> Sebastian
>