On Tue, Oct 22, 2019 at 6:56 AM Christophe Leroy <christophe.le...@c-s.fr> wrote: > > > >>> The performance is rather disappoiting. That's most likely all > >>> calculation in the C implementation are based on 64 bits math and > >>> converted to 32 bits at the very end. I guess C implementation should > >>> use 32 bits math like the assembly VDSO does as of today. > >> > >>> gettimeofday: vdso: 750 nsec/call > >>> > >>> gettimeofday: vdso: 1533 nsec/call > > > > Small improvement (3%) with the proposed change: > > > > gettimeofday: vdso: 1485 nsec/call > > By inlining do_hres() I get the following: > > gettimeofday: vdso: 1072 nsec/call >
A perf report might be informative.
