x86/vmware: Read tsc_khz only once at boot time (cf113729) · Commits · 戴 / test

arch/x86/kernel/cpu/vmware.c

+18 −19

Original line number	Diff line number	Diff line
		@@ -47,6 +47,8 @@
		"2"(VMWARE_HYPERVISOR_PORT), "3"(UINT_MAX) : \
		"memory");

		static unsigned long vmware_tsc_khz __ro_after_init;

		static inline int __vmware_platform(void)
		{
		uint32_t eax, ebx, ecx, edx;
		@@ -56,35 +58,32 @@ static inline int __vmware_platform(void)

		static unsigned long vmware_get_tsc_khz(void)
		{
		uint64_t tsc_hz, lpj;
		return vmware_tsc_khz;
		}

		static void __init vmware_platform_setup(void)
		{
		uint32_t eax, ebx, ecx, edx;
		uint64_t lpj, tsc_khz;

		VMWARE_PORT(GETHZ, eax, ebx, ecx, edx);

		tsc_hz = eax \| (((uint64_t)ebx) << 32);
		do_div(tsc_hz, 1000);
		BUG_ON(tsc_hz >> 32);
		if (ebx != UINT_MAX) {
		lpj = tsc_khz = eax \| (((uint64_t)ebx) << 32);
		do_div(tsc_khz, 1000);
		WARN_ON(tsc_khz >> 32);
		pr_info("TSC freq read from hypervisor : %lu.%03lu MHz\n",
		(unsigned long) tsc_hz / 1000,
		(unsigned long) tsc_hz % 1000);
		(unsigned long) tsc_khz / 1000,
		(unsigned long) tsc_khz % 1000);

		if (!preset_lpj) {
		lpj = ((u64)tsc_hz * 1000);
		do_div(lpj, HZ);
		preset_lpj = lpj;
		}

		return tsc_hz;
		}

		static void __init vmware_platform_setup(void)
		{
		uint32_t eax, ebx, ecx, edx;

		VMWARE_PORT(GETHZ, eax, ebx, ecx, edx);

		if (ebx != UINT_MAX) {
		vmware_tsc_khz = tsc_khz;
		x86_platform.calibrate_tsc = vmware_get_tsc_khz;

		#ifdef CONFIG_X86_LOCAL_APIC
		/* Skip lapic calibration since we know the bus frequency. */
		lapic_timer_frequency = ecx / HZ;