From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Kirill A. Shutemov" <kirill@shutemov.name>
Subject: Re: [PATCH v2 6/7] fs/proc/task_mmu.c: cleanup the "tail_vma" horror
 in m_next()
Date: Wed, 6 Aug 2014 13:17:18 +0300
Message-ID: <20140806101718.GB30703@node.dhcp.inet.fi>
References: <20140805194627.GA30693@redhat.com>
 <20140805194703.GA30739@redhat.com>
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Cc: Andrew Morton <akpm@linux-foundation.org>,
	Alexander Viro <viro@zeniv.linux.org.uk>,
	Cyrill Gorcunov <gorcunov@openvz.org>,
	David Howells <dhowells@redhat.com>,
	"David S. Miller" <davem@davemloft.net>,
	"Eric W. Biederman" <ebiederm@xmission.com>,
	"Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Sasha Levin <levinsasha928@gmail.com>,
	linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
To: Oleg Nesterov <oleg@redhat.com>
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In-Reply-To: <20140805194703.GA30739@redhat.com>
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On Tue, Aug 05, 2014 at 09:47:03PM +0200, Oleg Nesterov wrote:
> 1. Kill the first "vma != NULL" check. Firstly this is not possible,
>    m_next() won't be called if ->start() or the previous ->next()
>    returns NULL.
> 
>    And if it was possible the 2nd "vma != tail_vma" check is buggy,
>    we should not wrongly return ->tail_vma.
> 
> 2. Make this function readable. The logic is very simple, we should
>    return check "vma != tail" once and return "vm_next || tail_vma".
> 
> Signed-off-by: Oleg Nesterov <oleg@redhat.com>

Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>

-- 
 Kirill A. Shutemov