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Subject: Re: [PATCH] KCOV: Introduced tracing unique covered PCs
To:     Dmitry Vyukov <dvyukov@google.com>
Cc:     Andrey Konovalov <andreyknvl@google.com>,
        Jonathan Corbet <corbet@lwn.net>,
        Andrew Morton <akpm@linux-foundation.org>,
        Wei Yongjun <weiyongjun1@huawei.com>,
        Maciej Grochowski <maciej.grochowski@pm.me>,
        kasan-dev <kasan-dev@googlegroups.com>,
        "open list:DOCUMENTATION" <linux-doc@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        syzkaller <syzkaller@googlegroups.com>
References: <20210211080716.80982-1-info@alexander-lochmann.de>
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From:   Alexander Lochmann <info@alexander-lochmann.de>
Message-ID: <46db8e40-b3b6-370c-98fe-37610b789596@alexander-lochmann.de>
Date:   Wed, 17 Mar 2021 22:10:25 +0100
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On 15.03.21 09:02, Dmitry Vyukov wrote:
>>> Does this introduce an additional real of t->kcov_mode?
>>> If yes, please reuse the value read in check_kcov_mode.
>> Okay. How do I get that value from check_kcov_mode() to the caller?
>> Shall I add an additional parameter to check_kcov_mode()?
> 
> Yes, I would try to add an additional pointer parameter for mode. I
> think after inlining the compiler should be able to regestrize it.
First, I'll go for the extra argument. However, the compiler doesn't
seem to inline check_kcov_mode(). Can I enforce inlining?
I'm using GCC 9.3 on Debian Testing.

- Alex

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