Re: [RFC patch 08/18] cnt32_to_63 should use smp_rmb()
From: David Howells
Date: Fri Nov 07 2008 - 11:22:41 EST
Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote:
> If gcc did that then it would need to generate static instances of
> inlined functions within individual compilation units. It would be a
> disaster for the kernel. For a start, functions which are "inlined" in kernel
> modules wouldn't be able to access their static storage and modprobing
> them would fail.
Do you expect a static inline function that lives in a header file and that
has a static variable in it to share that static variable over all instances
of that function in a program? Or do you expect the static variable to be
limited at the file level? Or just at the invocation level?
> Does mn10300's get_cycles() really count backwards?
Yes, because the value is generated by a pair of cascaded 16-bit hardware
down-counters.
> The first two callsites I looked at (crypto/tcrypt.c and fs/ext4/mballoc.c)
> assume that it is an upcounter.
Hmmm... I didn't occur to me that get_cycles() was available for use outside
of arch code. Possibly it wasn't so used when I first came up with the code.
I should probably make it count the other way.
David
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/