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Subject: Re: [PATCH v2 1/4] kernfs: kvmalloc xattr value instead of kmalloc
From:   Joe Perches <joe@perches.com>
To:     Tejun Heo <tj@kernel.org>
Cc:     Daniel Xu <dxu@dxuuu.xyz>, cgroups@vger.kernel.org,
        lizefan@huawei.com, hannes@cmpxchg.org, shakeelb@google.com,
        linux-kernel@vger.kernel.org, gregkh@linuxfoundation.org,
        kernel-team@fb.com
Date:   Mon, 09 Mar 2020 12:58:49 -0700
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On Mon, 2020-03-09 at 15:51 -0400, Tejun Heo wrote:
> On Mon, Mar 09, 2020 at 12:41:05PM -0700, Joe Perches wrote:
> > If the need is to allocate from a single block of memory,
> > perhaps you need a submemory allocator like gen_pool.
> > (gennalloc.h)
> > 
> > Dunno.  Maybe i just don't quite understand your need.
> 
> vmalloc is the right thing to do here. vmalloc space isn't a scarce
> resource on any 64bit machines. On 32bits, which basically are tiny
> machines at this point, these allocations are both size and quantity
> limited by other factors (e.g. each cgroup consumes way more memory).

This feels like driving spikes into a living thing
more than into a
corpse.

I've still got more than a few 32-bit devices around.