Re: [PATCH] Force UNIX domain sockets to be built in

On Mon, Dec 31, 2007 at 04:19:23PM +0100, Bodo Eggert wrote:
On Mon, 31 Dec 2007, Adrian Bunk wrote:
On Mon, Dec 31, 2007 at 02:26:42PM +0100, Bodo Eggert wrote:
On Mon, 31 Dec 2007, Adrian Bunk wrote:
On Mon, Dec 31, 2007 at 01:09:43PM +0100, Bodo Eggert wrote:

As suggested by Adrian Bunk, UNIX domain sockets should always be built in
on normal systems. This is especially true since udev needs these sockets
and fails to run if UNIX=m.

Signed-Off-By: Bodo Eggert <7eggert@xxxxxx>

---
Last minute change: I decided against making it a bool because embedded
folks might depend on a small kernel image. Edited in the patch below.
...

Is this just a purely theoretical thought or is this a reasonable use
case people actually use in practice?

For now, it's a theoretical thought, but having an embedded device, I can
see the reason for $EVERYTHING=m there.

The only advantage I see is that the kernel image you have to flash
can be made smaller - with the disadvantage that the running kernel
is bigger by more than 10%.

If you don't believe me, try it yourself:
Build all drivers statically into your kernel, and then compare the
vmlinux sizes with CONFIG_MODULES=n and CONFIG_MODULES=y.

If you'd aim for a small kernel image, you would build anything as a module
that is not requred for booting.
...

Small kernel image to flash (e.g. due to a size limit there), if you
would aim for a small running kernel you wouldn't use modules.

And I'm not so sure about the image size without seeing actual numbers,
e.g. for your device.

Especially comparing your all-modular approach with a CONFIG_MODULES=n
kernel using Denys' section garbage collection patches in both cases
would be interesting.

I'm not claiming you are wrong, all I say is that I'm not convinced
without actual numbers that you are right.

cu
Adrian

--

"Is there not promise of rain?" Ling Tan asked suddenly out
of the darkness. There had been need of rain for many days.
"Only a promise," Lao Er said.
Pearl S. Buck - Dragon Seed

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