diff options
Diffstat (limited to 'kernel/time/clocksource.c')
-rw-r--r-- | kernel/time/clocksource.c | 20 |
1 files changed, 19 insertions, 1 deletions
diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index 80189f6f1c5a..592bf584d1d2 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -509,6 +509,18 @@ static ssize_t sysfs_override_clocksource(struct sys_device *dev, } } + /* + * Check to make sure we don't switch to a non-highres capable + * clocksource if the tick code is in oneshot mode (highres or nohz) + */ + if (tick_oneshot_mode_active() && + !(ovr->flags & CLOCK_SOURCE_VALID_FOR_HRES)) { + printk(KERN_WARNING "%s clocksource is not HRT compatible. " + "Cannot switch while in HRT/NOHZ mode\n", ovr->name); + ovr = NULL; + override_name[0] = 0; + } + /* Reselect, when the override name has changed */ if (ovr != clocksource_override) { clocksource_override = ovr; @@ -537,7 +549,13 @@ sysfs_show_available_clocksources(struct sys_device *dev, spin_lock_irq(&clocksource_lock); list_for_each_entry(src, &clocksource_list, list) { - count += snprintf(buf + count, + /* + * Don't show non-HRES clocksource if the tick code is + * in one shot mode (highres=on or nohz=on) + */ + if (!tick_oneshot_mode_active() || + (src->flags & CLOCK_SOURCE_VALID_FOR_HRES)) + count += snprintf(buf + count, max((ssize_t)PAGE_SIZE - count, (ssize_t)0), "%s ", src->name); } |