2022-04-16 01:21:39

by Rik van Riel

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Subject: Re: [PATCH v4 bpf 2/4] page_alloc: use vmalloc_huge for large system hash

On Fri, 2022-04-15 at 09:44 -0700, Song Liu wrote:
> Use vmalloc_huge() in alloc_large_system_hash() so that large system
> hash
> (>= PMD_SIZE) could benefit from huge pages. Note that vmalloc_huge
> only
> allocates huge pages for systems with HAVE_ARCH_HUGE_VMALLOC.
>
> Reviewed-by: Christoph Hellwig <[email protected]>
> Signed-off-by: Song Liu <[email protected]>

Reviewed-by: Rik van Riel <[email protected]>


2022-04-26 08:32:37

by Geert Uytterhoeven

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Subject: Re: [PATCH v4 bpf 2/4] page_alloc: use vmalloc_huge for large system hash

Hi Song,

On Fri, 2022-04-15 at 09:44 -0700, Song Liu wrote:
> > Use vmalloc_huge() in alloc_large_system_hash() so that large system
> > hash
> > (>= PMD_SIZE) could benefit from huge pages. Note that vmalloc_huge
> > only
> > allocates huge pages for systems with HAVE_ARCH_HUGE_VMALLOC.
> >
> > Reviewed-by: Christoph Hellwig <[email protected]>
> > Signed-off-by: Song Liu <[email protected]>
>
> Reviewed-by: Rik van Riel <[email protected]>

Thanks for your patch, which is now commit f2edd118d02dd114
("page_alloc: use vmalloc_huge for large system hash") upstream
(and which hasn't been in linux-next before).

As reported by [email protected], this is breaking e.g.
m68k/m5272c3_defconfig with:

page_alloc.c:(.init.text+0x13de): undefined reference to `vmalloc_huge'

vmalloc_huge() is provided by mm/vmalloc.c, which is not
compiled if CONFIG_MMU=n.

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds