ping. Any comment is appreciate.
Thanks
Minfei
On 05/28/16 at 08:27P, Minfei Huang wrote:
> There is a generic function __pvclock_read_cycles to be used to get both
> flags and cycles. For function pvclock_read_flags, it's useless to get
> cycles value. To make this function be more effective, get this variable
> flags directly in function.
>
> Signed-off-by: Minfei Huang <mngh...@gmail.com>
> ---
> v1:
> - Get rid of __pvclock_read_cycles according to Andy's suggestion
> ---
> arch/x86/kernel/pvclock.c | 7 +++++--
> 1 file changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/kernel/pvclock.c b/arch/x86/kernel/pvclock.c
> index 7f82fe0..06c58ce 100644
> --- a/arch/x86/kernel/pvclock.c
> +++ b/arch/x86/kernel/pvclock.c
> @@ -61,11 +61,14 @@ void pvclock_resume(void)
> u8 pvclock_read_flags(struct pvclock_vcpu_time_info *src)
> {
> unsigned version;
> - cycle_t ret;
> u8 flags;
>
> do {
> - version = __pvclock_read_cycles(src, &ret, &flags);
> + version = src->version;
> + /* Make the latest version visible */
> + smp_rmb();
> +
> + flags = src->flags;
> /* Make sure that the version double-check is last. */
> smp_rmb();
> } while ((src->version & 1) || version != src->version);
> --
> 2.6.3
>
