!3306 improve gettimeofday() performance in user space

Merge Pull Request from: @ci-robot 
 
PR sync from: Yang Yingliang <yangyingliang@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/YHKNSX4KKFYDIZG6PFMBJYN2PUPIOMV4/ 
Don't trap kernel to read the counter register, do this in userspace to
improve performance.

Yang Yingliang (3):
  arm64: arch_timer: Disable CNTVCT_EL0 trap if workaround is enabled
  vdso: do cntvct workaround in the VDSO
  arm64: arch_timer: disable
    CONFIG_ARM_ARCH_TIMER_WORKAROUND_IN_USERSPACE


-- 
2.25.1
 
https://gitee.com/openeuler/kernel/issues/I8LFBU 
 
Link:https://gitee.com/openeuler/kernel/pulls/3306

 

Reviewed-by: Wei Li <liwei391@huawei.com>
Reviewed-by: Zhang Jianhua <chris.zjh@huawei.com>
Reviewed-by: Xie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>