On Wed, Aug 31, 2022, Jim Mattson wrote:
On Wed, Aug 31, 2022 at 7:31 AM cgel.zte@gmail.com wrote:
diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h index 0cbc71b7af50..75920678f34d 100644 --- a/tools/testing/selftests/kvm/include/x86_64/processor.h +++ b/tools/testing/selftests/kvm/include/x86_64/processor.h @@ -237,7 +237,6 @@ static inline uint64_t get_desc64_base(const struct desc64 *desc) static inline uint64_t rdtsc(void) { uint32_t eax, edx;
uint64_t tsc_val; /* * The lfence is to wait (on Intel CPUs) until all previous * instructions have been executed. If software requires RDTSC to be@@ -245,8 +244,8 @@ static inline uint64_t rdtsc(void) * execute LFENCE immediately after RDTSC */ __asm__ __volatile__("lfence; rdtsc; lfence" : "=a"(eax), "=d"(edx));
tsc_val = ((uint64_t)edx) << 32 | eax;return tsc_val;
return ((uint64_t)edx) << 32 | eax;}
This does beg the question: "Why?"
Yeah, for this one I think having a local variable adds value.