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Date:   Wed, 7 Feb 2018 09:19:36 -0800
From:   Matthew Wilcox <willy@infradead.org>
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     Christopher Lameter <cl@linux.com>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        Kirill Tkhai <ktkhai@virtuozzo.com>, josh@joshtriplett.org,
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        mingo@redhat.com, penberg@kernel.org, rientjes@google.com,
        iamjoonsoo.kim@lge.com, akpm@linux-foundation.org,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        brouer@redhat.com, rao.shoaib@oracle.com
Subject: Re: [PATCH 0/2] rcu: Transform kfree_rcu() into kvfree_rcu()
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On Wed, Feb 07, 2018 at 12:09:49PM -0500, Steven Rostedt wrote:
> > Maybe lets implement malloc(), free() and realloc() in the kernel to be
> > consistent with user space use as possible? Only use the others
> > allocation variants for special cases.
> 
> They would need to drop the GFP part and default to GFP_KERNEL.

Yes, exactly.

> > So malloc would check allocation sizes and if < 2* PAGE_SIZE use kmalloc()
> > otherwise vmalloc().
> 
> Please no, I hate subtle internal decisions like this. It makes
> debugging much more difficult, when allocating dynamic sized variables.
> When something works at one size but not the other.

You know we already have kvmalloc()?