From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754649Ab1LMB0s (ORCPT ); Mon, 12 Dec 2011 20:26:48 -0500 Received: from mail-gx0-f174.google.com ([209.85.161.174]:53910 "EHLO mail-gx0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753649Ab1LMB0r (ORCPT ); Mon, 12 Dec 2011 20:26:47 -0500 From: Andy Lutomirski To: linux-kernel@vger.kernel.org, Kumar Sundararajan , john stultz , Arun Sharma Cc: Peter Zijlstra , Ingo Molnar , Thomas Gleixner , Andy Lutomirski Subject: [RFC 0/2] ABI for clock_gettime_ns Date: Mon, 12 Dec 2011 17:26:36 -0800 Message-Id: X-Mailer: git-send-email 1.7.7.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On x86-64, clock_gettime is so fast that the overhead converting to and from nanoseconds is non-negligible. clock_gettime_ns is a different interface that is potentially faster. If people like the ABI, I'll implement an optimized version. For the git-inclined, this series is at https://git.kernel.org/?p=linux/kernel/git/luto/linux.git;a=shortlog;h=refs/heads/timing/clock_gettime_ns/rfc_v1 Andy Lutomirski (2): Add clock_gettime_ns syscall x86-64: Add __vdso_clock_gettime_ns vsyscall arch/x86/include/asm/unistd_64.h | 2 + arch/x86/vdso/vclock_gettime.c | 70 +++++++++++++++++++++++++++++--------- arch/x86/vdso/vdso.lds.S | 7 ++++ include/linux/syscalls.h | 2 + kernel/posix-timers.c | 29 ++++++++++++++++ 5 files changed, 94 insertions(+), 16 deletions(-) -- 1.7.7.4