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-rw-r--r--include/asm-i386/tsc.h6
1 files changed, 4 insertions, 2 deletions
diff --git a/include/asm-i386/tsc.h b/include/asm-i386/tsc.h
index 3f3c1fa000b4..62c091ffcccc 100644
--- a/include/asm-i386/tsc.h
+++ b/include/asm-i386/tsc.h
@@ -35,14 +35,16 @@ static inline cycles_t get_cycles(void)
35static __always_inline cycles_t get_cycles_sync(void) 35static __always_inline cycles_t get_cycles_sync(void)
36{ 36{
37 unsigned long long ret; 37 unsigned long long ret;
38 unsigned eax; 38 unsigned eax, edx;
39 39
40 /* 40 /*
41 * Use RDTSCP if possible; it is guaranteed to be synchronous 41 * Use RDTSCP if possible; it is guaranteed to be synchronous
42 * and doesn't cause a VMEXIT on Hypervisors 42 * and doesn't cause a VMEXIT on Hypervisors
43 */ 43 */
44 alternative_io(ASM_NOP3, ".byte 0x0f,0x01,0xf9", X86_FEATURE_RDTSCP, 44 alternative_io(ASM_NOP3, ".byte 0x0f,0x01,0xf9", X86_FEATURE_RDTSCP,
45 "=A" (ret), "0" (0ULL) : "ecx", "memory"); 45 ASM_OUTPUT2("=a" (eax), "=d" (edx)),
46 "a" (0U), "d" (0U) : "ecx", "memory");
47 ret = (((unsigned long long)edx) << 32) | ((unsigned long long)eax);
46 if (ret) 48 if (ret)
47 return ret; 49 return ret;
48 50