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SubjectRe: [PATCH 3/4] x86: open-code register save/restore in trace_hardirqs thunks
On Sat, Jan 10, 2015 at 12:17:13PM -0800, Andy Lutomirski wrote:
> I asked this once, and someone told me that push/pop has lower
> throughput. I find this surprising.

Implicit dependency on %rsp probably. The MOVs allow you to start more
stuff out-of-order I'd guess...

> Tt could be worth adding a macro along the lines of pushq_cfi_save
> that does the pushq_cfi and the CFI_REL_OFFSET.

Yep, for balance.

--
Regards/Gruss,
Boris.

Sent from a fat crate under my desk. Formatting is fine.
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