From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751844AbbLZM00 (ORCPT ); Sat, 26 Dec 2015 07:26:26 -0500 Received: from mout.gmx.net ([212.227.17.20]:64061 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751073AbbLZM0Y (ORCPT ); Sat, 26 Dec 2015 07:26:24 -0500 To: Thomas Gleixner Cc: Linux Kernel Development , linux-parisc From: Helge Deller Subject: timerfd_settime/timerfd_gettime issue ? X-Enigmail-Draft-Status: N1110 Message-ID: <567E8766.6020707@gmx.de> Date: Sat, 26 Dec 2015 13:26:14 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.1.0 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Provags-ID: V03:K0:nhtB768uzxnS9AJ1aoGPEMC5ngnk3ZiVZcUHdk4z1CA6R2h8++n Ldwr6ahaNo3NX+zNl1eXEotu25aKnP8W4KGhY8ivCT/5VfQ6ZNL636A0oOGskrEwaCMwt5K Y763qJIQn8dQ/JBcYU0lYpMMBiuDiSQkKBXMkhIPh59NMVCf+tQ6ezkZqvs24Zuts/PInuE 0Rn+nyypOauVnj36K0K2w== X-UI-Out-Filterresults: notjunk:1;V01:K0:12/5j6xRBvs=:B0l2dmlkVDkpaleJztOdDb Rua+Og6C+P+jauNKDHEu372Kk/0V6E66ELsCPzAhR3d37i/PwtLAzdnCxNQ9fXNXBJrncYer6 +sX4e2ti9qrhHjol82vjcg1eHLAZXLc9pXUFOXjYPN+11ccYN+9LuqBlypWdzQd5s/qieftxA mS85pnNZDKW4lQ7vHhwECxAQgPXDpllMPEwAKVpfWelMqiRrKvzfbop8hMTdH+KGapiSaGhNH Xgd6K28UD82mGc8WY7j8yMNjn25DVpqIw2YFOj5ciSCuep1RLNAfL4hnjXfOswf//GN7SU+WO LjAL9DUgfQEpJfS2CD6FxHZR+mmpWUa8UyDpKsRGKuaNxA/onUx4E+5nkjS0rKOthXEV9LZ8s voymdvy2edCSRqi9QYP+XbPETKC662aeP6Esit6WZrQ/Q5PVRcXt/pgmjTBRbQZfdZW63+5JY LQmIYqKkh7+R7FxzW8T5uJdO7J6OemABnwJDYy7eYWE0dUxr7wp2tvqR98Nd5rCEgnpt4WGAA Fqt9e0C7at9p6PdDMPpsU407ark/TWTIfNet67Bt3Wh5VO8wKTYYiUsSk2toSF+dwHhj1zFoc kZYTZ0am1ghj1Lunj7agSUl9/fdGXy086OkdeJbKVIRJxn6FvpgQ/VsRNloGqBzvTB6Z815pf EgM07b1OW0Yv/Tl6fKlego4fV0ptPdlxjIbfZkVWsCZN4ho9GuFtXaxc6mj3gMsxlCJxgUdat aZlJ+U8aOmGIJ0Oj7KY/HfCQedEMGpSKfZam5M/iClKbZE2lHuzvV2+UHJx3lJ2lUvyks67SS oaXz/+r Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Thomas, I see a strange behavior on the parisc platform, for which I'm not sure if it's intended or if there is a bug somewhere. The program calls timerfd_settime() and sets a timer (e.g. sec=0, nsec=100000000). Directly after setting the timer it calls timerfd_gettime() and receives (sec=0, nsec=103914413). The second nsec is higher than the initial nsec value which was set. Does timerfd_settime() maybe tries to add the initial time it takes to start the timer? Any idea or hint? Thanks, Helge Background: I'm debugging the build-failure on debian for the liblinux-fd-perl package: https://buildd.debian.org/status/fetch.php?pkg=liblinux-fd-perl&arch=hppa&ver=0.011-1&stamp=1443355593 Here is a log which I get from kernel after adding some printks. The problematic line is #3. [ 465.888000] timerfd_settime: interval (sec=0, nsec=0) it_value (sec=0, nsec=100000000) [ 466.196000] timerfd_settime: interval (sec=0, nsec=100000000) it_value (sec=0, nsec=100000000) [ 466.300000] timerfd_gettime: interval (sec=0, nsec=100000000) it_value (sec=0, nsec=103914413) [ 466.404000] timerfd_gettime: interval (sec=0, nsec=100000000) it_value (sec=0, nsec=97444552) [ 466.508000] timerfd_gettime: interval (sec=0, nsec=100000000) it_value (sec=0, nsec=92611704) [ 466.616000] timerfd_gettime: interval (sec=0, nsec=100000000) it_value (sec=0, nsec=87376859) [ 466.720000] timerfd_gettime: interval (sec=0, nsec=100000000) it_value (sec=0, nsec=82538534) [ 466.824000] timerfd_gettime: interval (sec=0, nsec=100000000) it_value (sec=0, nsec=77293289) [ 466.928000] timerfd_gettime: interval (sec=0, nsec=100000000) it_value (sec=0, nsec=72501584) [ 467.036000] timerfd_gettime: interval (sec=0, nsec=100000000) it_value (sec=0, nsec=67377673) [ 467.140000] timerfd_gettime: interval (sec=0, nsec=100000000) it_value (sec=0, nsec=62631601) [ 467.244000] timerfd_gettime: interval (sec=0, nsec=100000000) it_value (sec=0, nsec=57401824)