RE: [PATCH 1/2] x86/mce: Only restart instruction after machinecheck recovery if it is safe

From: Luck, Tony
Date: Mon May 14 2012 - 12:16:09 EST


>> + int restartable;
>
> Is it me or does this look like a flag, or a bitfield? Instead of
> wasting a whole integer for a single bit of information.

I could make it "int flags;" and "#define MCE_INFO_RESTARTABLE 1"
to make it clear that we have lots more bits available for special
cases?

> It will probably end up the same size though due to compiler padding
> since this struct is currently 4 + 2*8 byte without the ->restartable
> thing.

Yup - we can't save any memory (unless we introduce more complexity to
the code ... low PAGE_SHIFT bits of the "paddr" field are simply thrown
away ... so we could allocate a bit there ... but I don't think that
the resulting ugliness is worth the memory savings).

-Tony
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