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From:   Kent Overstreet <kent.overstreet@linux.dev>
To:     Mike Rapoport <rppt@kernel.org>
Cc:     Song Liu <song@kernel.org>, linux-mm@kvack.org,
        Andrew Morton <akpm@linux-foundation.org>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Rick Edgecombe <rick.p.edgecombe@intel.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Vlastimil Babka <vbabka@suse.cz>, linux-kernel@vger.kernel.org,
        x86@kernel.org
Subject: Re: [RFC PATCH 1/5] mm: intorduce __GFP_UNMAPPED and unmapped_alloc()
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On Fri, May 19, 2023 at 11:29:45AM +0300, Mike Rapoport wrote:
> Your allocator implicitly relies on vmalloc because of module_alloc ;-)
> 
> What I was thinking is that we can replace module_alloc() calls in your
> allocator with something based on my unmapped_alloc(). If we make the part
> that refills the cache also take care of creating the mapping in the
> module address space, that should cover everything.

Yeah, that's exactly what I was thinking :)

Liam was also just mentioning on IRC vmalloc lock contention came up
again at LSF, and that's historically always been an isuse - going with
your patchset for the backend nicely avoids that.

If I have time (hah! big if :) I'll see if I can cook up a patchset that
combines our two approaches over the weekend.