From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755726AbcANQzq (ORCPT ); Thu, 14 Jan 2016 11:55:46 -0500 Received: from www.linutronix.de ([62.245.132.108]:58566 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754914AbcANQzn (ORCPT ); Thu, 14 Jan 2016 11:55:43 -0500 Message-Id: <20160114163744.582215466@linutronix.de> User-Agent: quilt/0.63-1 Date: Thu, 14 Jan 2016 16:54:45 -0000 From: Thomas Gleixner To: LKML Cc: Ingo Molnar , Peter Zijlstra , Helge Deller , John Stultz , linux-m68k@vger.kernel.org, dhowells@redhat.com Subject: [patch 0/4] hrtimers: Handle remaining time correctly for CONFIG_TIME_LOW_RES=y X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Helge reported, that timerfd returns occasionally remaining time larger than the relative time which was used to arm the timer. This is caused by the extra jiffy which we add in hrtimer_start_range_ns() if CONFIG_TIME_LOW_RES=y. This is not only an issue for timerfd. We have the same problem in posix-timers and itimers. This series adds infrastructure to the core to handle that cases and converts the users over to it. Thanks, tglx --- fs/timerfd.c | 2 - include/linux/hrtimer.h | 34 +++++++++++++++++++++++++-- kernel/time/hrtimer.c | 55 ++++++++++++++++++++++++++++++--------------- kernel/time/itimer.c | 2 - kernel/time/posix-timers.c | 2 - kernel/time/timer_list.c | 2 - 6 files changed, 72 insertions(+), 25 deletions(-) From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Gleixner Subject: [patch 0/4] hrtimers: Handle remaining time correctly for CONFIG_TIME_LOW_RES=y Date: Thu, 14 Jan 2016 16:54:45 -0000 Message-ID: <20160114163744.582215466@linutronix.de> Return-path: Sender: linux-m68k-owner@vger.kernel.org List-Id: linux-m68k@vger.kernel.org To: LKML Cc: Ingo Molnar , Peter Zijlstra , Helge Deller , John Stultz , linux-m68k@lists.linux-m68k.org, dhowells@redhat.com Helge reported, that timerfd returns occasionally remaining time larger than the relative time which was used to arm the timer. This is caused by the extra jiffy which we add in hrtimer_start_range_ns() if CONFIG_TIME_LOW_RES=y. This is not only an issue for timerfd. We have the same problem in posix-timers and itimers. This series adds infrastructure to the core to handle that cases and converts the users over to it. Thanks, tglx --- fs/timerfd.c | 2 - include/linux/hrtimer.h | 34 +++++++++++++++++++++++++-- kernel/time/hrtimer.c | 55 ++++++++++++++++++++++++++++++--------------- kernel/time/itimer.c | 2 - kernel/time/posix-timers.c | 2 - kernel/time/timer_list.c | 2 - 6 files changed, 72 insertions(+), 25 deletions(-)