Messages in this thread | | | From | Geert Uytterhoeven <> | Date | Tue, 28 Feb 2017 21:15:12 +0100 | Subject | Re: [PATCH v2 2/3] spi: allocate spi_board_info entries one by one |
| |
On Tue, Feb 28, 2017 at 7:54 PM, Mark Brown <broonie@kernel.org> wrote: > On Tue, Feb 28, 2017 at 10:24:17AM -0800, Dmitry Torokhov wrote: >> On Tue, Feb 28, 2017 at 09:16:50AM +0000, Mark Brown wrote: >> > On Mon, Feb 27, 2017 at 08:18:56PM -0800, Dmitry Torokhov wrote: >> > > Lists of spi_board_info entries registered with spi_register_board_info() >> > > can be quite long; instead of forcing memory allocator find contagious > >> > Do you have numbers on that? > >> Hm, so the largest array seems to be in >> arch/blackfin/mach-bf537/boards/stamp.c at max of 43 entries. The new >> board info is ether 60 or 72 bytes, so we get 2 or 3K table. Not above >> page, but still could be packed I think. > > Oh wow, that's impressively large. Still not sure the optimization is > particularly worth it though, it's small change in the grand scheme of > things. OTOH it's a small change.
Given this is done during early boot, what's the probability of not having sufficient contiguous memory?
>> If we decide that we want to keep single chunk I'll just change the >> allocation to kcalloc. Let me know. > > I'd be inclined to do that because it requires less thinking about the > value of what should be a very small optimization either way but > whatever :)
Tada...
commit f9bdb7fdd2cac17bdc9c344b6036e6939fa087cd Author: Markus Elfring <elfring@users.sourceforge.net> Date: Fri Jan 13 12:28:04 2017 +0100
spi: Use kcalloc() in spi_register_board_info()
Gr{oetje,eeting}s,
Geert
-- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
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
| |