clockevents.c revision 320ab2b0b1e08e3805a3e1084a2f0eb1938d5d67
1d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner/* 2d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * linux/kernel/time/clockevents.c 3d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * 4d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * This file contains functions which manage clock event devices. 5d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * 6d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * Copyright(C) 2005-2006, Thomas Gleixner <tglx@linutronix.de> 7d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * Copyright(C) 2005-2007, Red Hat, Inc., Ingo Molnar 8d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * Copyright(C) 2006-2007, Timesys Corp., Thomas Gleixner 9d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * 10d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * This code is licenced under the GPL version 2. For details see 11d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * kernel-base/COPYING. 12d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner */ 13d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 14d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner#include <linux/clockchips.h> 15d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner#include <linux/hrtimer.h> 16d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner#include <linux/init.h> 17d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner#include <linux/module.h> 18d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner#include <linux/notifier.h> 19d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner#include <linux/smp.h> 20d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner#include <linux/sysdev.h> 21d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 22d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner/* The registered clock event devices */ 23d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixnerstatic LIST_HEAD(clockevent_devices); 24d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixnerstatic LIST_HEAD(clockevents_released); 25d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 26d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner/* Notification for clock events */ 27d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixnerstatic RAW_NOTIFIER_HEAD(clockevents_chain); 28d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 29d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner/* Protection for the above */ 30d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixnerstatic DEFINE_SPINLOCK(clockevents_lock); 31d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 32d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner/** 33d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * clockevents_delta2ns - Convert a latch value (device ticks) to nanoseconds 34d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * @latch: value to convert 35d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * @evt: pointer to clock event device descriptor 36d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * 37d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * Math helper, returns latch value converted to nanoseconds (bound checked) 38d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner */ 39d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixnerunsigned long clockevent_delta2ns(unsigned long latch, 40d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner struct clock_event_device *evt) 41d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner{ 42d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner u64 clc = ((u64) latch << evt->shift); 43d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 4445fe4fe19120a22f7339f5bb110447170c25fca9Ingo Molnar if (unlikely(!evt->mult)) { 4545fe4fe19120a22f7339f5bb110447170c25fca9Ingo Molnar evt->mult = 1; 4645fe4fe19120a22f7339f5bb110447170c25fca9Ingo Molnar WARN_ON(1); 4745fe4fe19120a22f7339f5bb110447170c25fca9Ingo Molnar } 4845fe4fe19120a22f7339f5bb110447170c25fca9Ingo Molnar 49d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner do_div(clc, evt->mult); 50d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner if (clc < 1000) 51d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner clc = 1000; 52d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner if (clc > LONG_MAX) 53d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner clc = LONG_MAX; 54d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 55d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner return (unsigned long) clc; 56d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner} 57d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 58d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner/** 59d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * clockevents_set_mode - set the operating mode of a clock event device 60d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * @dev: device to modify 61d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * @mode: new mode 62d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * 63d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * Must be called with interrupts disabled ! 64d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner */ 65d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixnervoid clockevents_set_mode(struct clock_event_device *dev, 66d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner enum clock_event_mode mode) 67d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner{ 68d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner if (dev->mode != mode) { 69d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner dev->set_mode(mode, dev); 70d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner dev->mode = mode; 71d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner } 72d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner} 73d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 74d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner/** 752344abbcbdb82140050e8be29d3d55e4f6fe860bThomas Gleixner * clockevents_shutdown - shutdown the device and clear next_event 762344abbcbdb82140050e8be29d3d55e4f6fe860bThomas Gleixner * @dev: device to shutdown 772344abbcbdb82140050e8be29d3d55e4f6fe860bThomas Gleixner */ 782344abbcbdb82140050e8be29d3d55e4f6fe860bThomas Gleixnervoid clockevents_shutdown(struct clock_event_device *dev) 792344abbcbdb82140050e8be29d3d55e4f6fe860bThomas Gleixner{ 802344abbcbdb82140050e8be29d3d55e4f6fe860bThomas Gleixner clockevents_set_mode(dev, CLOCK_EVT_MODE_SHUTDOWN); 812344abbcbdb82140050e8be29d3d55e4f6fe860bThomas Gleixner dev->next_event.tv64 = KTIME_MAX; 822344abbcbdb82140050e8be29d3d55e4f6fe860bThomas Gleixner} 832344abbcbdb82140050e8be29d3d55e4f6fe860bThomas Gleixner 842344abbcbdb82140050e8be29d3d55e4f6fe860bThomas Gleixner/** 85d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * clockevents_program_event - Reprogram the clock event device. 86d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * @expires: absolute expiry time (monotonic clock) 87d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * 88d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * Returns 0 on success, -ETIME when the event is in the past. 89d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner */ 90d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixnerint clockevents_program_event(struct clock_event_device *dev, ktime_t expires, 91d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner ktime_t now) 92d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner{ 93d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner unsigned long long clc; 94d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner int64_t delta; 95d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 96167b1de3ee4e50d65a2bd0a2667c9cd48faf54f3Thomas Gleixner if (unlikely(expires.tv64 < 0)) { 97167b1de3ee4e50d65a2bd0a2667c9cd48faf54f3Thomas Gleixner WARN_ON_ONCE(1); 98167b1de3ee4e50d65a2bd0a2667c9cd48faf54f3Thomas Gleixner return -ETIME; 99167b1de3ee4e50d65a2bd0a2667c9cd48faf54f3Thomas Gleixner } 100167b1de3ee4e50d65a2bd0a2667c9cd48faf54f3Thomas Gleixner 101d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner delta = ktime_to_ns(ktime_sub(expires, now)); 102d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 103d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner if (delta <= 0) 104d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner return -ETIME; 105d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 106d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner dev->next_event = expires; 107d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 108d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner if (dev->mode == CLOCK_EVT_MODE_SHUTDOWN) 109d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner return 0; 110d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 111d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner if (delta > dev->max_delta_ns) 112d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner delta = dev->max_delta_ns; 113d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner if (delta < dev->min_delta_ns) 114d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner delta = dev->min_delta_ns; 115d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 116d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner clc = delta * dev->mult; 117d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner clc >>= dev->shift; 118d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 119d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner return dev->set_next_event((unsigned long) clc, dev); 120d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner} 121d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 122d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner/** 123d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * clockevents_register_notifier - register a clock events change listener 124d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner */ 125d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixnerint clockevents_register_notifier(struct notifier_block *nb) 126d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner{ 127d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner int ret; 128d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 129d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner spin_lock(&clockevents_lock); 130d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner ret = raw_notifier_chain_register(&clockevents_chain, nb); 131d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner spin_unlock(&clockevents_lock); 132d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 133d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner return ret; 134d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner} 135d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 136d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner/* 137d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * Notify about a clock event change. Called with clockevents_lock 138d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * held. 139d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner */ 140d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixnerstatic void clockevents_do_notify(unsigned long reason, void *dev) 141d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner{ 142d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner raw_notifier_call_chain(&clockevents_chain, reason, dev); 143d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner} 144d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 145d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner/* 1463eb056764dd806bbe84eb604e45e7470feeaafd8Li Zefan * Called after a notify add to make devices available which were 147d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * released from the notifier call. 148d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner */ 149d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixnerstatic void clockevents_notify_released(void) 150d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner{ 151d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner struct clock_event_device *dev; 152d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 153d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner while (!list_empty(&clockevents_released)) { 154d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner dev = list_entry(clockevents_released.next, 155d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner struct clock_event_device, list); 156d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner list_del(&dev->list); 157d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner list_add(&dev->list, &clockevent_devices); 158d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner clockevents_do_notify(CLOCK_EVT_NOTIFY_ADD, dev); 159d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner } 160d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner} 161d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 162d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner/** 163d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * clockevents_register_device - register a clock event device 164d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * @dev: device to register 165d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner */ 166d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixnervoid clockevents_register_device(struct clock_event_device *dev) 167d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner{ 168d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner BUG_ON(dev->mode != CLOCK_EVT_MODE_UNUSED); 169320ab2b0b1e08e3805a3e1084a2f0eb1938d5d67Rusty Russell BUG_ON(!dev->cpumask); 170320ab2b0b1e08e3805a3e1084a2f0eb1938d5d67Rusty Russell 17145fe4fe19120a22f7339f5bb110447170c25fca9Ingo Molnar /* 17245fe4fe19120a22f7339f5bb110447170c25fca9Ingo Molnar * A nsec2cyc multiplicator of 0 is invalid and we'd crash 17345fe4fe19120a22f7339f5bb110447170c25fca9Ingo Molnar * on it, so fix it up and emit a warning: 17445fe4fe19120a22f7339f5bb110447170c25fca9Ingo Molnar */ 17545fe4fe19120a22f7339f5bb110447170c25fca9Ingo Molnar if (unlikely(!dev->mult)) { 17645fe4fe19120a22f7339f5bb110447170c25fca9Ingo Molnar dev->mult = 1; 17745fe4fe19120a22f7339f5bb110447170c25fca9Ingo Molnar WARN_ON(1); 17845fe4fe19120a22f7339f5bb110447170c25fca9Ingo Molnar } 179d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 180d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner spin_lock(&clockevents_lock); 181d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 182d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner list_add(&dev->list, &clockevent_devices); 183d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner clockevents_do_notify(CLOCK_EVT_NOTIFY_ADD, dev); 184d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner clockevents_notify_released(); 185d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 186d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner spin_unlock(&clockevents_lock); 187d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner} 188d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 189d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner/* 190d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * Noop handler when we shut down an event device 191d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner */ 1927c1e76897492d92b6a1c2d6892494d39ded9680cVenkatesh Pallipadivoid clockevents_handle_noop(struct clock_event_device *dev) 193d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner{ 194d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner} 195d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 196d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner/** 197d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * clockevents_exchange_device - release and request clock devices 198d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * @old: device to release (can be NULL) 199d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * @new: device to request (can be NULL) 200d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * 201d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * Called from the notifier chain. clockevents_lock is held already 202d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner */ 203d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixnervoid clockevents_exchange_device(struct clock_event_device *old, 204d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner struct clock_event_device *new) 205d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner{ 206d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner unsigned long flags; 207d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 208d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner local_irq_save(flags); 209d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner /* 210d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * Caller releases a clock event device. We queue it into the 211d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * released list and do a notify add later. 212d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner */ 213d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner if (old) { 214d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner clockevents_set_mode(old, CLOCK_EVT_MODE_UNUSED); 215d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner list_del(&old->list); 216d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner list_add(&old->list, &clockevents_released); 217d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner } 218d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 219d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner if (new) { 220d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner BUG_ON(new->mode != CLOCK_EVT_MODE_UNUSED); 2212344abbcbdb82140050e8be29d3d55e4f6fe860bThomas Gleixner clockevents_shutdown(new); 222d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner } 223d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner local_irq_restore(flags); 224d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner} 225d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 226de68d9b173ee657115dd0e584c2365b7954253a5Thomas Gleixner#ifdef CONFIG_GENERIC_CLOCKEVENTS 227d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner/** 228d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * clockevents_notify - notification about relevant events 229d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner */ 230d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixnervoid clockevents_notify(unsigned long reason, void *arg) 231d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner{ 2320b858e6ff9a38b987a83d22e6f2a2f621c80608dLi Zefan struct list_head *node, *tmp; 2330b858e6ff9a38b987a83d22e6f2a2f621c80608dLi Zefan 234d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner spin_lock(&clockevents_lock); 235d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner clockevents_do_notify(reason, arg); 236d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner 237d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner switch (reason) { 238d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner case CLOCK_EVT_NOTIFY_CPU_DEAD: 239d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner /* 240d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * Unregister the clock event devices which were 241d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner * released from the users in the notify chain. 242d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner */ 2430b858e6ff9a38b987a83d22e6f2a2f621c80608dLi Zefan list_for_each_safe(node, tmp, &clockevents_released) 2440b858e6ff9a38b987a83d22e6f2a2f621c80608dLi Zefan list_del(node); 245d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner break; 246d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner default: 247d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner break; 248d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner } 249d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner spin_unlock(&clockevents_lock); 250d316c57ff6bfad9557462b9100f25c6260d2b774Thomas Gleixner} 251d316c57ff6bfad9557462b9100f25c6260d2b774Thomas GleixnerEXPORT_SYMBOL_GPL(clockevents_notify); 252de68d9b173ee657115dd0e584c2365b7954253a5Thomas Gleixner#endif 253