Re: [PATCH] blackfin: Cleanup linker script using new linker script macros.

From: Mike Frysinger
Date: Wed Sep 16 2009 - 16:38:03 EST


On Wed, Sep 16, 2009 at 16:26, Sam Ravnborg wrote:
> On Wed, Sep 16, 2009 at 11:58:01AM -0400, Tim Abbott wrote:
>> On Tue, 15 Sep 2009, Mike Frysinger wrote:
>> > the larger padding in the initramfs is kind of annoying as i cant see
>> > any need to pad it to PAGE_SIZE. Âsince the initramfs is released with
>> > the rest of the init section, it doesnt need whole pages. Âa quick
>> > test shows that it does waste a few kb in reality. Âdefault build for
>> > BF533-STAMP for example shows 0x1000 difference.
>> >
>> > in terms of correctness, this change misses a reference to the now
>> > deleted .init.ramfs:
>> > - Â Â Â .init.ramfs :
>> > - Â Â Â {
>> > - Â Â Â .....
>> > - Â Â Â }
>> > -
>> > Â Â Â Â.text_l1 L1_CODE_START : AT(LOADADDR(.init.ramfs) + SIZEOF(.init.ramfs))
>> >
>> > so that .text_l1 needs to updated to refer to the new section before
>> > it (.exit.data in this case). Âonce i make that change, the resulting
>> > link looks the same (minus the initramfs thing mentioned earlier), and
>> > it does boot.
>>
>> OK. ÂI guess we should plan to modify the INIT_DATA_SECTION macro to add
>> another argument specifying an alignment level for .init.ramfs. ÂIt'd be
>> inconvenient to add that right now since there are a lot of patches in
>> linux-next or otherwise in flight that introduce uses of
>> INIT_DATA_SECTION, and those patches would all be broken by changing this
>> now. ÂOnce the dust settles on that for this release, I'll submit a patch
>> adding said argument to INIT_DATA_SECTION.
>
> But this is all discarded during runtime so the added alignment has no cost in the end - no?

once things are booted, there should be no difference. but
storage/boot costs increase (you have to store/extract/copy that extra
data). you know how miserly we embedded people like to be ;).
-mike
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