Re: [PATCH 3/3] arm64, mm: Use IPIs for TLB invalidation.

From: Sergei Shtylyov
Date: Sat Jul 11 2015 - 18:06:47 EST


Hello.

On 07/11/2015 11:25 PM, David Daney wrote:

From: David Daney <david.daney@xxxxxxxxxx>

Most broadcast TLB invalidations are unnecessary. So when
invalidating for a given mm/vma target the only the needed CPUs via

The only the needed?

and IPI.

For global TLB invalidations, also use IPI.

Tested on Cavium ThunderX.

This change reduces 'time make -j48' on kernel from 139s to 116s (83%
as long).

The patch is needed because of a ThunderX Pass1 erratum: Exclusive
store operations unreliable in the presence of broadcast TLB
invalidations. The performance improvements shown make it compelling
even without the erratum workaround need.

Signed-off-by: David Daney <david.daney@xxxxxxxxxx>

WBR, Sergei

--
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/