From ed911b43adb889c37a37fa57a995f0b460c633b6 Mon Sep 17 00:00:00 2001 From: Minfei Huang Date: Sat, 28 May 2016 20:27:43 +0800 Subject: [PATCH] pvclock: Get rid of __pvclock_read_cycles in function pvclock_read_flags 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 Signed-off-by: Paolo Bonzini --- 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 7f82fe0a6807..06c58ce46762 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);