Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751470AbaKKBib (ORCPT ); Mon, 10 Nov 2014 20:38:31 -0500 Received: from www.meduna.org ([92.240.244.38]:37429 "EHLO meduna.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751221AbaKKBia (ORCPT ); Mon, 10 Nov 2014 20:38:30 -0500 X-Greylist: delayed 2561 seconds by postgrey-1.27 at vger.kernel.org; Mon, 10 Nov 2014 20:38:29 EST Message-ID: <54615E89.7020902@meduna.org> Date: Tue, 11 Nov 2014 01:55:37 +0100 From: Stanislav Meduna User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:31.0) Gecko/20100101 Thunderbird/31.2.0 MIME-Version: 1.0 To: linux-rt-users@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Highres timers broken on i.mx28 for CONFIG_HZ_PERIODIC Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Authenticated-User: stano@meduna.org X-Authenticator: dovecot_plain X-Spam-Score: -6.9 X-Spam-Score-Int: -68 X-Exim-Version: 4.72 (build at 13-Jul-2014 12:42:58) X-Date: 2014-11-11 01:55:44 X-Connected-IP: 95.105.163.217:54744 X-Message-Linecount: 170 X-Body-Linecount: 160 X-Message-Size: 4009 X-Body-Size: 3576 X-Received-Count: 1 X-Recipient-Count: 2 X-Local-Recipient-Count: 2 X-Local-Recipient-Defer-Count: 0 X-Local-Recipient-Fail-Count: 0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, something between 3.12.19(-rt30) and 3.12.31(-rt45) broke hrtimers on (at least) i.MX28 for CONFIG_HZ_PERIODIC. Switching to CONFIG_NO_HZ_IDLE restores them. Is this the expected behaviour or a regression? The difference in the /proc/timer_list is the Tick Device: mode: 0 (new) or 1 (old) # cat /proc/timer_list Timer List Version: v0.7 HRTIMER_MAX_CLOCK_BASES: 4 now at 3551448891259 nsecs cpu: 0 clock 0: .base: c03694e0 .index: 0 .resolution: 4000000 nsecs .get_time: ktime_get .offset: 0 nsecs active timers: ... clock 1: .base: c0369520 .index: 1 .resolution: 4000000 nsecs .get_time: ktime_get_real .offset: 0 nsecs active timers: clock 2: .base: c0369560 .index: 2 .resolution: 4000000 nsecs .get_time: ktime_get_boottime .offset: 0 nsecs active timers: clock 3: .base: c03695a0 .index: 3 .resolution: 4000000 nsecs .get_time: ktime_get_clocktai .offset: 0 nsecs active timers: .expires_next : 9223372036854775807 nsecs .hres_active : 0 .nr_events : 0 .nr_retries : 0 .nr_hangs : 0 .max_hang_time : 0 nsecs .nohz_mode : 0 .last_tick : 0 nsecs .tick_stopped : 0 .idle_jiffies : 0 .idle_calls : 0 .idle_sleeps : 0 .idle_entrytime : 0 nsecs .idle_waketime : 0 nsecs .idle_exittime : 0 nsecs .idle_sleeptime : 0 nsecs .iowait_sleeptime: 0 nsecs .last_jiffies : 0 .next_jiffies : 0 .idle_expires : 0 nsecs jiffies: 812862 Tick Device: mode: 0 Per CPU device: 0 Clock Event Device: mxs_timrot max_delta_ns: 178956969028 min_delta_ns: 1000 mult: 51539608 shift: 31 mode: 3 next_event: 3551452000000 nsecs set_next_event: timrotv2_set_next_event set_mode: mxs_set_mode event_handler: tick_handle_periodic retries: 0 In the 3.2.19 it was Timer List Version: v0.7 HRTIMER_MAX_CLOCK_BASES: 4 now at 280235727915168 nsecs cpu: 0 clock 0: .base: c03654c0 .index: 0 .resolution: 1 nsecs .get_time: ktime_get .offset: 0 nsecs active timers: ... clock 1: .base: c0365500 .index: 1 .resolution: 1 nsecs .get_time: ktime_get_real .offset: 1415385038639056250 nsecs active timers: clock 2: .base: c0365540 .index: 2 .resolution: 1 nsecs .get_time: ktime_get_boottime .offset: 0 nsecs active timers: clock 3: .base: c0365580 .index: 3 .resolution: 1 nsecs .get_time: ktime_get_clocktai .offset: 1415385038639056250 nsecs active timers: .expires_next : 280235730396263 nsecs .hres_active : 1 .nr_events : 207916570 .nr_retries : 2164032 .nr_hangs : 7 .max_hang_time : 107499 nsecs .nohz_mode : 0 .last_tick : 0 nsecs .tick_stopped : 0 .idle_jiffies : 0 .idle_calls : 0 .idle_sleeps : 0 .idle_entrytime : 0 nsecs .idle_waketime : 0 nsecs .idle_exittime : 0 nsecs .idle_sleeptime : 0 nsecs .iowait_sleeptime: 0 nsecs .last_jiffies : 0 .next_jiffies : 0 .idle_expires : 0 nsecs jiffies: 69983932 Tick Device: mode: 1 Per CPU device: 0 Clock Event Device: mxs_timrot max_delta_ns: 178956969028 min_delta_ns: 1000 mult: 51539608 shift: 31 mode: 3 next_event: 280235730396263 nsecs set_next_event: timrotv2_set_next_event set_mode: mxs_set_mode event_handler: hrtimer_interrupt retries: 0 Thanks -- Stano -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/