tick/sched: Use tick_next_period for lockless quick check

mainline inclusion
from mainline-5.11-rc1
commit 372acbba
category: feature
feature: Deep isolation
bugzilla: https://gitee.com/openeuler/kernel/issues/I4N00D
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=372acbbaa80940189593f9d69c7c069955f24f7a



--------------------------------

No point in doing calculations.

   tick_next_period = last_jiffies_update + tick_period

Just check whether now is before tick_next_period to figure out whether
jiffies need an update.

Add a comment why the intentional data race in the quick check is safe or
not so safe in a 32bit corner case and why we don't worry about it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20201117132006.337366695@linutronix.de


Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com>
Reviewed-by: Chao Liu <liuchao173@huawei.com>
Reviewed-by: Chen Hui <judy.chenhui@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>