On 03/09/2011 09:04 AM, Somebody in the thread at some point said:
I take it this magic of SMP or not is hidden in this config layering scheme
you mentioned and it isn't really using the same config for say igep0020 and
No, it is in the black depths of ARM assembly and TBH, it is voodoo to
me. Nothing to do with kernel config as such. The SMP kernel, at
runtime, (binary) patches itself to convert locking primitives to
no-ops in the UP case. Or something to the effect.
Hum my IGEP0020 config here has CONFIG_BROKEN_ON_SMP=y set so I guess
this is to do with what you mentioned.
Panda. In any event, there's a performance tradeoff running SMP kernel on
uniprocessor to consider too.
Apparently, with this one-time patching (per boot) there isn't such a tradeoff.
OK thanks for the explanation.
Absolutely that's the future... in fact the bootloader should work the same
way with one per-arch bootloader that detects what it is running on at
runtime, and at that point device-specific point hwpacks become very thin or
non-existent and there's an epic reduction in how many different binaries
are needed to support many boards.
I can hear the collective sighs of appreciation from distribution maintainers :)
^^
-Andy
_______________________________________________
linaro-dev mailing list
linaro-dev@lists.linaro.org
http://lists.linaro.org/mailman/listinfo/linaro-dev
