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Subject: Re: [RFC V3] mm: Generalize and rename notify_page_fault() as
 kprobe_page_fault()
To:     Anshuman Khandual <anshuman.khandual@arm.com>,
        Matthew Wilcox <willy@infradead.org>
Cc:     linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org,
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        linux-sh@vger.kernel.org, sparclinux@vger.kernel.org,
        x86@kernel.org, Andrew Morton <akpm@linux-foundation.org>,
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        Mark Rutland <mark.rutland@arm.com>,
        Christophe Leroy <christophe.leroy@c-s.fr>,
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        Andrey Konovalov <andreyknvl@google.com>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Paul Mackerras <paulus@samba.org>,
        Russell King <linux@armlinux.org.uk>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will.deacon@arm.com>,
        Tony Luck <tony.luck@intel.com>,
        Fenghua Yu <fenghua.yu@intel.com>,
        Martin Schwidefsky <schwidefsky@de.ibm.com>,
        Heiko Carstens <heiko.carstens@de.ibm.com>,
        Yoshinori Sato <ysato@users.sourceforge.jp>,
        "David S. Miller" <davem@davemloft.net>,
        Thomas Gleixner <tglx@linutronix.de>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Andy Lutomirski <luto@kernel.org>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Vineet Gupta <vgupta@synopsys.com>,
        linux-snps-arc@lists.infradead.org,
        James Hogan <jhogan@kernel.org>, linux-mips@vger.kernel.org,
        Ralf Baechle <ralf@linux-mips.org>,
        Paul Burton <paul.burton@mips.com>
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From:   Dave Hansen <dave.hansen@intel.com>
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Message-ID: <33c6a1cd-5c07-e623-28e5-f31f6fe30394@intel.com>
Date:   Sun, 9 Jun 2019 21:57:29 -0700
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Sender: linux-kernel-owner@vger.kernel.org
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On 6/9/19 9:34 PM, Anshuman Khandual wrote:
>> Do you really think this is easier to read?
>>
>> Why not just move the x86 version to include/linux/kprobes.h, and replace
>> the int with bool?
> Will just return bool directly without an additional variable here as suggested
> before. But for the conditional statement, I guess the proposed one here is more
> compact than the x86 one.

FWIW, I don't think "compact" is generally a good goal for code.  Being
readable is 100x more important than being compact and being un-compact
is only a problem when it hurts readability.

For a function like the one in question, having the individual return
conditions clearly commented is way more important than saving 10 lines
of code.