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Date:   Wed, 30 Nov 2022 11:39:47 +0200
From:   Mike Rapoport <rppt@kernel.org>
To:     Song Liu <song@kernel.org>
Cc:     "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>,
        "peterz@infradead.org" <peterz@infradead.org>,
        "bpf@vger.kernel.org" <bpf@vger.kernel.org>,
        "linux-mm@kvack.org" <linux-mm@kvack.org>,
        "hch@lst.de" <hch@lst.de>, "x86@kernel.org" <x86@kernel.org>,
        "akpm@linux-foundation.org" <akpm@linux-foundation.org>,
        "mcgrof@kernel.org" <mcgrof@kernel.org>,
        "Lu, Aaron" <aaron.lu@intel.com>
Subject: Re: [PATCH bpf-next v2 0/5] execmem_alloc for BPF programs
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On Mon, Nov 21, 2022 at 07:52:12AM -0700, Song Liu wrote:
> On Sun, Nov 20, 2022 at 3:41 AM Mike Rapoport <rppt@kernel.org> wrote:
> > > >
> > > > The most obvious one to implement Peter's suggestion with VM_TOPDOWN_VMAP
> > > > so that execmem_alloc() can be actually used by modules.
> > >
> > > Current implementation is an alternative to VM_TOPDOWN_VMAP. I am
> > > very sure it works for modules just like VM_TOPDOWN_VMAP solution.
> >
> > It might, but it still does not. And until they do I consider these
> > patches as an optimization for BFP rather than unification of code
> > allocations.
> 
> We haven't got module to use execmem_alloc yet, that's true. But
> this has nothing to do with VM_TOPDOWN_VMAP at all.

The point is that Peter suggested a way to make module_alloc() use 2M
pages, so that all code allocations could benefit from it. Your
execmem_alloc() isn't anywhere near this.
 
> Thanks,
> Song

-- 
Sincerely yours,
Mike.