On Wed, Aug 31, 2022 at 7:31 AM cgel.zte@gmail.com wrote:

From: Jinpeng Cui cui.jinpeng2@zte.com.cn

Return value directly from expression instead of getting value from redundant variable tsc_val.

Nit: I think you mean 'superfluous' rather than 'redundant'?

Reported-by: Zeal Robot zealci@zte.com.cn Signed-off-by: Jinpeng Cui cui.jinpeng2@zte.com.cn

---

tools/testing/selftests/kvm/include/x86_64/processor.h | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)

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?"

On 8/31/22 08:31, cgel.zte@gmail.com wrote:

From: Jinpeng Cui cui.jinpeng2@zte.com.cn

Return value directly from expression instead of getting value from redundant variable tsc_val.

Reported-by: Zeal Robot zealci@zte.com.cn Signed-off-by: Jinpeng Cui cui.jinpeng2@zte.com.cn

---

tools/testing/selftests/kvm/include/x86_64/processor.h | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)

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; }

static inline uint64_t rdtscp(uint32_t *aux)

My understanding is that this patch isn't coming from individuals that work for ZTE. We won't be able to accept these patches. Refer to the following for reasons why we can't accept these patches.

https://patchwork.kernel.org/project/linux-kselftest/patch/20220920063202.21...

thanks, -- Shuah