Re: [RFC][PATCH 0/10] 64 bit resources

From: Kumar Gala
Date: Tue Mar 28 2006 - 11:31:38 EST



On Mar 24, 2006, at 12:05 PM, Vivek Goyal wrote:

On Fri, Mar 24, 2006 at 01:12:17AM -0800, Andrew Morton wrote:
Vivek Goyal <vgoyal@xxxxxxxxxx> wrote:

Hi,

Here is an attempt to implement support for 64 bit resources. This will
enable memory more than 4G to be exported through /proc/iomem, which is used
by kexec/kdump to determine the physical memory layout of the system.

...

We used "make allyesconfig" with CONFIG_DEBUG_INFO=n on 2.6.16-mm1.

i386
----

vmlinux size without patch: 40191425
vmlinux size with path: 40244677
vmlinux size bloat: 52K (.13%)

ugh, that's actually a surprising amount of growth. Could you look into it
a bit more please? Where's it coming from? text? data?


Andrew, most of it seems to be coming from .text. I have pasted few results
below.


A bit of growth in drivers is probably OK, as all machines load a tiny
subset of them. But if it's core kernel, not so good. What is the effect
on allnoconfig?

Here are more compilation results with allnoconfig, allmodconfig and
allyesconfig on i386. I have picked section sizes from the output of readelf.

allnoconfig
----------

vmlinux bloat: 0

.text bloat: 1008 bytes
.data bloat: 672 bytes.
.init.text bloat: 128 bytes
.init.data bloat: 0 bytes

(Not sure why vmlinux size difference is zero, given the fact that few
sections are showing bloated size)


allmodconfig (CONFIG_DEBUG_INFO=n)
------------

vmlinux bloat:4096 bytes

.text bloat: 4064 bytes
.init.text bloat: 470 bytes
.data bloat: 640 bytes


allyesconfig (CONFIG_DEBUG_INFO=n)
-----------

vmlinux size bloat: 52K

.text bloat: 28.5K
.init_text bloat: 5K
.eh_frame bloat: 16K (What's that. Looks big)
.rodata bloat: 152 bytes
.data bloat: 768 bytes

So the bloat seems be in the drivers as expected.

Vivek, mind updating these against -mm2 also, can you fixup arch/ powerpc/kernel/pci_32.c.

Andrew, any issues in merging into -mm?

- kumar
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