On 04/05/2013 03:21 AM, Michael Ellerman wrote:

On Tue, Mar 19, 2013 at 04:55:31PM -0300, Adhemerval Zanella wrote:

quoted

Hi all,

This patch implement the time syscall as vDSO. I have a glibc patch
to use it as IFUNC (as latest gettimeofday patch). Below the perf
numbers:

Baseline PPC32: 380 nsec
Baseline PPC64: 352 nsec
vdso PPC32:      20 nsec
vdso PPC64:      20 nsec

I focused on 64 bit kernel, do I need to provide a scheme for 32 bits
as well?

You did provide a 32-bit implementation. I take it you haven't tested
that though? Can you test it?

Hi,

I didn't build a 32 bit kernel, but I tested 32 bits binaries (that uses
the VDSO32 implantation) without any issue. Performance gains are similar.