BMC/Intel-BMC/linux.git/kernel/time/tick-oneshot.c, branch dev-4.17

clockevents: Fix kernel messages split across multiple lines

2018-04-17T15:18:04+00:00

Convert the clockevents driver from old-style printk() to pr_info() and pr_cont(), to fix split kernel messages like below: Clockevents: could not switch to one-shot mode: dummy_timer is not functional. Signed-off-by: Geert Uytterhoeven Signed-off-by: Thomas Gleixner Cc: Frederic Weisbecker Link: https://lkml.kernel.org/r/1522942018-14471-1-git-send-email-geert%2Brenesas@glider.be

clockevents: Update clockevents device next_event on stop

2017-11-01T17:20:17+00:00

clockevent_device::next_event holds the next timer event of a clock event device. The value is updated in clockevents_program_event(), i.e. when the hardware timer is armed for the next expiry. When there are no software timers armed on a CPU, the corresponding per CPU clockevent device is brought into ONESHOT_STOPPED state, but clockevent_device::next_event is not updated, because clockevents_program_event() is not called. So the content of clockevent_device::next_event is stale, which is not an issue when real hardware is used. But the hrtimer broadcast device relies on that information and the stale value causes spurious wakeups. Update clockevent_device::next_event to KTIME_MAX when it has been brought into ONESHOT_STOPPED state to avoid spurious wakeups. This reflects the proper expiry time of the stopped timer: infinity. [ tglx: Massaged changelog ] Signed-off-by: Prasad Sodagudi Signed-off-by: Thomas Gleixner Cc: viresh.kumar@linaro.org Link: https://lkml.kernel.org/r/1509043042-32486-1-git-send-email-psodagud@codeaurora.org

ktime: Get rid of the union

2016-12-25T16:21:22+00:00

ktime is a union because the initial implementation stored the time in scalar nanoseconds on 64 bit machine and in a endianess optimized timespec variant for 32bit machines. The Y2038 cleanup removed the timespec variant and switched everything to scalar nanoseconds. The union remained, but become completely pointless. Get rid of the union and just keep ktime_t as simple typedef of type s64. The conversion was done with coccinelle and some manual mopping up. Signed-off-by: Thomas Gleixner Cc: Peter Zijlstra

clockevents: Provide functions to set and get the state

2015-06-02T12:40:47+00:00

We want to rename dev->state, so provide proper get and set functions. Rename clockevents_set_state() to clockevents_switch_state() to avoid confusion. Signed-off-by: Thomas Gleixner Cc: Viresh Kumar Cc: Peter Zijlstra

clockevents: Use helpers to check the state of a clockevent device

2015-06-02T12:40:47+00:00

Use accessor functions to check the state of clockevent devices in core code. Signed-off-by: Viresh Kumar Cc: linaro-kernel@lists.linaro.org Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/fa2b9869fd17f210eaa156ec2b594efd0230b6c7.1432192527.git.viresh.kumar@linaro.org Signed-off-by: Thomas Gleixner

clockevents: Stop unused clockevent devices

2015-05-19T14:18:11+00:00

To avoid getting spurious interrupts on a tickless CPU, clockevent device can now be stopped by switching to ONESHOT_STOPPED state. The natural place for handling this transition is tick_program_event(). On 'expires == KTIME_MAX', we skip programming the event and so we need to fix such call sites as well, to always call tick_program_event() irrespective of the expires value. Once the clockevent device is required again, check if it was earlier put into ONESHOT_STOPPED state. If yes, switch its state to ONESHOT before programming its event. To make sure we haven't missed any corner case, add a WARN() for the case where we try to reprogram clockevent device while we aren't configured in ONESHOT_STOPPED state. Signed-off-by: Viresh Kumar Cc: linaro-kernel@lists.linaro.org Cc: Frederic Weisbecker Cc: Kevin Hilman Cc: Daniel Lezcano Cc: Preeti U Murthy Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/5146b07be7f0bc497e0ebae036590ec2fa73e540.1428031396.git.viresh.kumar@linaro.org Signed-off-by: Thomas Gleixner

clockevents: Manage device's state separately for the core

2015-03-27T09:26:19+00:00

'enum clock_event_mode' is used for two purposes today: - to pass mode to the driver of clockevent device::set_mode(). - for managing state of the device for clockevents core. For supporting new modes/states we have moved away from the legacy set_mode() callback to new per-mode/state callbacks. New modes/states shouldn't be exposed to the legacy (now OBSOLOTE) callbacks and so we shouldn't add new states to 'enum clock_event_mode'. Lets have separate enums for the two use cases mentioned above. Keep using the earlier enum for legacy set_mode() callback and mark it OBSOLETE. And add another enum to clearly specify the possible states of a clockevent device. This also renames the newly added per-mode callbacks to reflect state changes. We haven't got rid of 'mode' member of 'struct clock_event_device' as it is used by some of the clockevent drivers and it would automatically die down once we migrate those drivers to the new interface. It ('mode') is only updated now for the drivers using the legacy interface. Suggested-by: Peter Zijlstra Suggested-by: Ingo Molnar Signed-off-by: Viresh Kumar Acked-by: Peter Zijlstra Cc: Daniel Lezcano Cc: Frederic Weisbecker Cc: Kevin Hilman Cc: Preeti U Murthy Cc: linaro-kernel@lists.linaro.org Cc: linaro-networking@linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/b6b0143a8a57bd58352ad35e08c25424c879c0cb.1425037853.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar

time: Replace __get_cpu_var uses

2014-08-26T17:45:44+00:00

Convert uses of __get_cpu_var for creating a address from a percpu offset to this_cpu_ptr. The two cases where get_cpu_var is used to actually access a percpu variable are changed to use this_cpu_read/raw_cpu_read. Reviewed-by: Thomas Gleixner Signed-off-by: Christoph Lameter Signed-off-by: Tejun Heo

clockevents: Make minimum delay adjustments configurable

2011-09-08T09:10:56+00:00

The automatic increase of the min_delta_ns of a clockevents device should be done in the clockevents code as the minimum delay is an attribute of the clockevents device. In addition not all architectures want the automatic adjustment, on a massively virtualized system it can happen that the programming of a clock event fails several times in a row because the virtual cpu has been rescheduled quickly enough. In that case the minimum delay will erroneously be increased with no way back. The new config symbol GENERIC_CLOCKEVENTS_MIN_ADJUST is used to enable the automatic adjustment. The config option is selected only for x86. Signed-off-by: Martin Schwidefsky Cc: john stultz Link: http://lkml.kernel.org/r/20110823133142.494157493@de.ibm.com Signed-off-by: Thomas Gleixner

time: Make do_timer() and xtime_lock local to kernel/time/

2011-01-31T18:26:50+00:00

All callers of do_timer() are converted to xtime_update(). The only users of xtime_lock are in kernel/time/. Make both local to kernel/time/ and remove them from the global header files. [ tglx: Reuse tick-internal.h instead of creating another local header file. Massaged changelog ] Signed-off-by: Torben Hohn Cc: Peter Zijlstra Cc: johnstul@us.ibm.com Cc: yong.zhang0@gmail.com Cc: hch@infradead.org Signed-off-by: Thomas Gleixner