X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=kernel%2Ftime%2Fclocksource.c;h=548c436a776bd35b40b7e9143f24a2743246650b;hb=afbf331ed1252c85753ac6790356c11e171f3d0b;hp=51b6a6a6158cab016aa11b09f0a65c1919c750ec;hpb=ec4883b015c3212f6f6d04fb2ff45f528492f598;p=linux-2.6 diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index 51b6a6a615..548c436a77 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -91,7 +91,6 @@ static void clocksource_ratewd(struct clocksource *cs, int64_t delta) cs->name, delta); cs->flags &= ~(CLOCK_SOURCE_VALID_FOR_HRES | CLOCK_SOURCE_WATCHDOG); clocksource_change_rating(cs, 0); - cs->flags &= ~CLOCK_SOURCE_WATCHDOG; list_del(&cs->wd_list); } @@ -142,8 +141,13 @@ static void clocksource_watchdog(unsigned long data) } if (!list_empty(&watchdog_list)) { - __mod_timer(&watchdog_timer, - watchdog_timer.expires + WATCHDOG_INTERVAL); + /* Cycle through CPUs to check if the CPUs stay synchronized to + * each other. */ + int next_cpu = next_cpu(raw_smp_processor_id(), cpu_online_map); + if (next_cpu >= NR_CPUS) + next_cpu = first_cpu(cpu_online_map); + watchdog_timer.expires += WATCHDOG_INTERVAL; + add_timer_on(&watchdog_timer, next_cpu); } spin_unlock(&watchdog_lock); } @@ -165,7 +169,7 @@ static void clocksource_check_watchdog(struct clocksource *cs) if (!started && watchdog) { watchdog_last = watchdog->read(); watchdog_timer.expires = jiffies + WATCHDOG_INTERVAL; - add_timer(&watchdog_timer); + add_timer_on(&watchdog_timer, first_cpu(cpu_online_map)); } } else { if (cs->flags & CLOCK_SOURCE_IS_CONTINUOUS) @@ -175,7 +179,7 @@ static void clocksource_check_watchdog(struct clocksource *cs) if (watchdog) del_timer(&watchdog_timer); watchdog = cs; - init_timer(&watchdog_timer); + init_timer_deferrable(&watchdog_timer); watchdog_timer.function = clocksource_watchdog; /* Reset watchdog cycles */ @@ -186,7 +190,8 @@ static void clocksource_check_watchdog(struct clocksource *cs) watchdog_last = watchdog->read(); watchdog_timer.expires = jiffies + WATCHDOG_INTERVAL; - add_timer(&watchdog_timer); + add_timer_on(&watchdog_timer, + first_cpu(cpu_online_map)); } } } @@ -207,15 +212,12 @@ static inline void clocksource_resume_watchdog(void) { } */ void clocksource_resume(void) { - struct list_head *tmp; + struct clocksource *cs; unsigned long flags; spin_lock_irqsave(&clocksource_lock, flags); - list_for_each(tmp, &clocksource_list) { - struct clocksource *cs; - - cs = list_entry(tmp, struct clocksource, list); + list_for_each_entry(cs, &clocksource_list, list) { if (cs->resume) cs->resume(); } @@ -334,6 +336,21 @@ void clocksource_change_rating(struct clocksource *cs, int rating) spin_unlock_irqrestore(&clocksource_lock, flags); } +/** + * clocksource_unregister - remove a registered clocksource + */ +void clocksource_unregister(struct clocksource *cs) +{ + unsigned long flags; + + spin_lock_irqsave(&clocksource_lock, flags); + list_del(&cs->list); + if (clocksource_override == cs) + clocksource_override = NULL; + next_clocksource = select_clocksource(); + spin_unlock_irqrestore(&clocksource_lock, flags); +} + #ifdef CONFIG_SYSFS /** * sysfs_show_current_clocksources - sysfs interface for current clocksource @@ -345,15 +362,13 @@ void clocksource_change_rating(struct clocksource *cs, int rating) static ssize_t sysfs_show_current_clocksources(struct sys_device *dev, char *buf) { - char *curr = buf; + ssize_t count = 0; spin_lock_irq(&clocksource_lock); - curr += sprintf(curr, "%s ", curr_clocksource->name); + count = snprintf(buf, PAGE_SIZE, "%s\n", curr_clocksource->name); spin_unlock_irq(&clocksource_lock); - curr += sprintf(curr, "\n"); - - return curr - buf; + return count; } /** @@ -369,7 +384,6 @@ static ssize_t sysfs_override_clocksource(struct sys_device *dev, const char *buf, size_t count) { struct clocksource *ovr = NULL; - struct list_head *tmp; size_t ret = count; int len; @@ -389,12 +403,11 @@ static ssize_t sysfs_override_clocksource(struct sys_device *dev, len = strlen(override_name); if (len) { + struct clocksource *cs; + ovr = clocksource_override; /* try to select it: */ - list_for_each(tmp, &clocksource_list) { - struct clocksource *cs; - - cs = list_entry(tmp, struct clocksource, list); + list_for_each_entry(cs, &clocksource_list, list) { if (strlen(cs->name) == len && !strcmp(cs->name, override_name)) ovr = cs; @@ -422,21 +435,21 @@ static ssize_t sysfs_override_clocksource(struct sys_device *dev, static ssize_t sysfs_show_available_clocksources(struct sys_device *dev, char *buf) { - struct list_head *tmp; - char *curr = buf; + struct clocksource *src; + ssize_t count = 0; spin_lock_irq(&clocksource_lock); - list_for_each(tmp, &clocksource_list) { - struct clocksource *src; - - src = list_entry(tmp, struct clocksource, list); - curr += sprintf(curr, "%s ", src->name); + list_for_each_entry(src, &clocksource_list, list) { + count += snprintf(buf + count, + max((ssize_t)PAGE_SIZE - count, (ssize_t)0), + "%s ", src->name); } spin_unlock_irq(&clocksource_lock); - curr += sprintf(curr, "\n"); + count += snprintf(buf + count, + max((ssize_t)PAGE_SIZE - count, (ssize_t)0), "\n"); - return curr - buf; + return count; } /* @@ -449,7 +462,7 @@ static SYSDEV_ATTR(available_clocksource, 0600, sysfs_show_available_clocksources, NULL); static struct sysdev_class clocksource_sysclass = { - set_kset_name("clocksource"), + .name = "clocksource", }; static struct sys_device device_clocksource = {