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-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html