x86/smpboot: Do not use BSP INIT delay and MWAIT to idle on Dhyana (0b13bec7) · Commits · 戴 / test

The Hygon Dhyana CPU uses no delay in smp_quirk_init_udelay(), and does HLT on idle just like AMD does. Signed-off-by:

Borislav Petkov <bp@suse.de> Cc: bp@alien8.de Cc: tglx@linutronix.de Cc: mingo@redhat.com Cc: hpa@zytor.com Cc: x86@kernel.org Cc: thomas.lendacky@amd.com Link: https://lkml.kernel.org/r/87000fa82e273f5967c908448414228faf61e077.1537533369.git.puwen@hygon.cn

arch/x86/kernel/smpboot.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -676,6 +676,7 @@ static void __init smp_quirk_init_udelay(void)

		/* if modern processor, use no delay */
		if (((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) && (boot_cpu_data.x86 == 6)) \|\|
		((boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) && (boot_cpu_data.x86 >= 0x18)) \|\|
		((boot_cpu_data.x86_vendor == X86_VENDOR_AMD) && (boot_cpu_data.x86 >= 0xF))) {
		init_udelay = 0;
		return;
		@@ -1592,7 +1593,8 @@ static inline void mwait_play_dead(void)
		void *mwait_ptr;
		int i;

		if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
		if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD \|\|
		boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
		return;
		if (!this_cpu_has(X86_FEATURE_MWAIT))
		return;