[no subject]

[Andi Kleen]

[Repost; I forgot to copy linux-kernel earlier. Apologies if you
see it twice.]

Skylake moved to 32 Last Branch Records, from previously 16. 
The current call stack LBR implementation reads all LBRs and
also saves/restores them on context switch. This patchkit
adds some optimizations to avoid extra costs in most cases
from the larger number of LBRs for call-stack, unless a nesting
larger than 16 is actually needed. It applies on top of the
earlier Skylake code. Some of the optimization will also benefit
earlier CPUs, such as Haswell.

note: one patch is for perf user space, the rest is kernel.

-Andi

--
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/