Merge branch 'x86-idle-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 idle updates from Ingo Molnar:
 "There were two bigger changes in this development cycle:

   - remove idle notifiers:

       32 files changed, 74 insertions(+), 803 deletions(-)

     These notifiers were of questionable value and the main usecase,
     the i7300 driver, was essentially unmaintained and can be removed,
     plus modern power management concepts don't need the callback - so
     use this golden opportunity and get rid of this opaque and fragile
     callback from a latency sensitive code path.

     (Len Brown, Thomas Gleixner)

   - improve the AMD Erratum 400 workaround that used high overhead MSR
     polling in the idle loop (Borisla Petkov, Thomas Gleixner)"

* 'x86-idle-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Remove empty idle.h header
  x86/amd: Simplify AMD E400 aware idle routine
  x86/amd: Check for the C1E bug post ACPI subsystem init
  x86/bugs: Separate AMD E400 erratum and C1E bug
  x86/cpufeature: Provide helper to set bugs bits
  x86/idle: Remove enter_idle(), exit_idle()
  x86: Remove x86_test_and_clear_bit_percpu()
  x86/idle: Remove is_idle flag
  x86/idle: Remove idle_notifier
  i7300_idle: Remove this driver

15 files changed, 65 insertions, 122 deletions

diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 2686894350a4..bb47e5eacd44 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -48,7 +48,6 @@
 #include <asm/io_apic.h>
 #include <asm/desc.h>
 #include <asm/hpet.h>
-#include <asm/idle.h>
 #include <asm/mtrr.h>
 #include <asm/time.h>
 #include <asm/smp.h>
@@ -894,11 +893,13 @@ void __init setup_boot_APIC_clock(void)
 
 	/* Setup the lapic or request the broadcast */
 	setup_APIC_timer();
+	amd_e400_c1e_apic_setup();
 }
 
 void setup_secondary_APIC_clock(void)
 {
 	setup_APIC_timer();
+	amd_e400_c1e_apic_setup();
 }
 
 /*
diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 48e6d84f173e..945e512a112a 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -48,7 +48,6 @@
 #include <linux/bootmem.h>
 
 #include <asm/irqdomain.h>
-#include <asm/idle.h>
 #include <asm/io.h>
 #include <asm/smp.h>
 #include <asm/cpu.h>
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 4daad1e39352..71cae73a5076 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -20,6 +20,10 @@
 
 #include "cpu.h"
 
+static const int amd_erratum_383[];
+static const int amd_erratum_400[];
+static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum);
+
 /*
  * nodes_per_socket: Stores the number of nodes per socket.
  * Refer to Fam15h Models 00-0fh BKDG - CPUID Fn8000_001E_ECX
@@ -592,11 +596,16 @@ static void early_init_amd(struct cpuinfo_x86 *c)
 	/* F16h erratum 793, CVE-2013-6885 */
 	if (c->x86 == 0x16 && c->x86_model <= 0xf)
 		msr_set_bit(MSR_AMD64_LS_CFG, 15);
-}
 
-static const int amd_erratum_383[];
-static const int amd_erratum_400[];
-static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum);
+	/*
+	 * Check whether the machine is affected by erratum 400. This is
+	 * used to select the proper idle routine and to enable the check
+	 * whether the machine is affected in arch_post_acpi_init(), which
+	 * sets the X86_BUG_AMD_APIC_C1E bug depending on the MSR check.
+	 */
+	if (cpu_has_amd_erratum(c, amd_erratum_400))
+		set_cpu_bug(c, X86_BUG_AMD_E400);
+}
 
 static void init_amd_k8(struct cpuinfo_x86 *c)
 {
@@ -777,9 +786,6 @@ static void init_amd(struct cpuinfo_x86 *c)
 	if (c->x86 > 0x11)
 		set_cpu_cap(c, X86_FEATURE_ARAT);
 
-	if (cpu_has_amd_erratum(c, amd_erratum_400))
-		set_cpu_bug(c, X86_BUG_AMD_APIC_C1E);
-
 	rdmsr_safe(MSR_AMD64_PATCH_LEVEL, &c->microcode, &dummy);
 
 	/* 3DNow or LM implies PREFETCHW */
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 9886cf490479..87f563946e6b 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1172,7 +1172,6 @@ void enable_sep_cpu(void)
 void __init identify_boot_cpu(void)
 {
 	identify_cpu(&boot_cpu_data);
-	init_amd_e400_c1e_mask();
 #ifdef CONFIG_X86_32
 	sysenter_setup();
 	enable_sep_cpu();
diff --git a/arch/x86/kernel/cpu/mcheck/mce_amd.c b/arch/x86/kernel/cpu/mcheck/mce_amd.c
index 1a0b0a0e5e2b..51ad0086b0bb 100644
--- a/arch/x86/kernel/cpu/mcheck/mce_amd.c
+++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c
@@ -24,7 +24,6 @@
 
 #include <asm/amd_nb.h>
 #include <asm/apic.h>
-#include <asm/idle.h>
 #include <asm/mce.h>
 #include <asm/msr.h>
 #include <asm/trace/irq_vectors.h>
diff --git a/arch/x86/kernel/cpu/mcheck/therm_throt.c b/arch/x86/kernel/cpu/mcheck/therm_throt.c
index 6b9dc4d18ccc..2f5c3418b18b 100644
--- a/arch/x86/kernel/cpu/mcheck/therm_throt.c
+++ b/arch/x86/kernel/cpu/mcheck/therm_throt.c
@@ -26,7 +26,6 @@
 
 #include <asm/processor.h>
 #include <asm/apic.h>
-#include <asm/idle.h>
 #include <asm/mce.h>
 #include <asm/msr.h>
 #include <asm/trace/irq_vectors.h>
diff --git a/arch/x86/kernel/cpu/mcheck/threshold.c b/arch/x86/kernel/cpu/mcheck/threshold.c
index fcf9ae9384f4..9beb092d68a5 100644
--- a/arch/x86/kernel/cpu/mcheck/threshold.c
+++ b/arch/x86/kernel/cpu/mcheck/threshold.c
@@ -6,7 +6,6 @@
 
 #include <asm/irq_vectors.h>
 #include <asm/apic.h>
-#include <asm/idle.h>
 #include <asm/mce.h>
 #include <asm/trace/irq_vectors.h>
 
diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index 8f44c5a50ab8..6c044543545e 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -25,7 +25,6 @@
 #include <asm/hyperv.h>
 #include <asm/mshyperv.h>
 #include <asm/desc.h>
-#include <asm/idle.h>
 #include <asm/irq_regs.h>
 #include <asm/i8259.h>
 #include <asm/apic.h>
diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
index 9f669fdd2010..7c6e9ffe4424 100644
--- a/arch/x86/kernel/irq.c
+++ b/arch/x86/kernel/irq.c
@@ -14,7 +14,6 @@
 #include <asm/apic.h>
 #include <asm/io_apic.h>
 #include <asm/irq.h>
-#include <asm/idle.h>
 #include <asm/mce.h>
 #include <asm/hw_irq.h>
 #include <asm/desc.h>
diff --git a/arch/x86/kernel/irq_64.c b/arch/x86/kernel/irq_64.c
index 9ebd0b0e73d9..6b0678a541e2 100644
--- a/arch/x86/kernel/irq_64.c
+++ b/arch/x86/kernel/irq_64.c
@@ -16,7 +16,6 @@
 #include <linux/uaccess.h>
 #include <linux/smp.h>
 #include <asm/io_apic.h>
-#include <asm/idle.h>
 #include <asm/apic.h>
 
 int sysctl_panic_on_stackoverflow;
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index fb5afc6356b2..36bc66416021 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -42,7 +42,6 @@
 #include <asm/traps.h>
 #include <asm/desc.h>
 #include <asm/tlbflush.h>
-#include <asm/idle.h>
 #include <asm/apic.h>
 #include <asm/apicdef.h>
 #include <asm/hypervisor.h>
@@ -267,13 +266,11 @@ do_async_page_fault(struct pt_regs *regs, unsigned long error_code)
 	case KVM_PV_REASON_PAGE_NOT_PRESENT:
 		/* page is swapped out by the host. */
 		prev_state = exception_enter();
-		exit_idle();
 		kvm_async_pf_task_wait((u32)read_cr2());
 		exception_exit(prev_state);
 		break;
 	case KVM_PV_REASON_PAGE_READY:
 		rcu_irq_enter();
-		exit_idle();
 		kvm_async_pf_task_wake((u32)read_cr2());
 		rcu_irq_exit();
 		break;
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 0888a879120f..43c36d8a6ae2 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -23,7 +23,6 @@
 #include <asm/cpu.h>
 #include <asm/apic.h>
 #include <asm/syscalls.h>
-#include <asm/idle.h>
 #include <asm/uaccess.h>
 #include <asm/mwait.h>
 #include <asm/fpu/internal.h>
@@ -65,23 +64,6 @@ __visible DEFINE_PER_CPU_SHARED_ALIGNED(struct tss_struct, cpu_tss) = {
 };
 EXPORT_PER_CPU_SYMBOL(cpu_tss);
 
-#ifdef CONFIG_X86_64
-static DEFINE_PER_CPU(unsigned char, is_idle);
-static ATOMIC_NOTIFIER_HEAD(idle_notifier);
-
-void idle_notifier_register(struct notifier_block *n)
-{
-	atomic_notifier_chain_register(&idle_notifier, n);
-}
-EXPORT_SYMBOL_GPL(idle_notifier_register);
-
-void idle_notifier_unregister(struct notifier_block *n)
-{
-	atomic_notifier_chain_unregister(&idle_notifier, n);
-}
-EXPORT_SYMBOL_GPL(idle_notifier_unregister);
-#endif
-
 /*
  * this gets called so that we can store lazy state into memory and copy the
  * current task into the new thread.
@@ -251,39 +233,9 @@ static inline void play_dead(void)
 }
 #endif
 
-#ifdef CONFIG_X86_64
-void enter_idle(void)
-{
-	this_cpu_write(is_idle, 1);
-	atomic_notifier_call_chain(&idle_notifier, IDLE_START, NULL);
-}
-
-static void __exit_idle(void)
-{
-	if (x86_test_and_clear_bit_percpu(0, is_idle) == 0)
-		return;
-	atomic_notifier_call_chain(&idle_notifier, IDLE_END, NULL);
-}
-
-/* Called from interrupts to signify idle end */
-void exit_idle(void)
-{
-	/* idle loop has pid 0 */
-	if (current->pid)
-		return;
-	__exit_idle();
-}
-#endif
-
 void arch_cpu_idle_enter(void)
 {
 	local_touch_nmi();
-	enter_idle();
-}
-
-void arch_cpu_idle_exit(void)
-{
-	__exit_idle();
 }
 
 void arch_cpu_idle_dead(void)
@@ -336,59 +288,33 @@ void stop_this_cpu(void *dummy)
 		halt();
 }
 
-bool amd_e400_c1e_detected;
-EXPORT_SYMBOL(amd_e400_c1e_detected);
-
-static cpumask_var_t amd_e400_c1e_mask;
-
-void amd_e400_remove_cpu(int cpu)
-{
-	if (amd_e400_c1e_mask != NULL)
-		cpumask_clear_cpu(cpu, amd_e400_c1e_mask);
-}
-
 /*
- * AMD Erratum 400 aware idle routine. We check for C1E active in the interrupt
- * pending message MSR. If we detect C1E, then we handle it the same
- * way as C3 power states (local apic timer and TSC stop)
+ * AMD Erratum 400 aware idle routine. We handle it the same way as C3 power
+ * states (local apic timer and TSC stop).
  */
 static void amd_e400_idle(void)
 {
-	if (!amd_e400_c1e_detected) {
-		u32 lo, hi;
-
-		rdmsr(MSR_K8_INT_PENDING_MSG, lo, hi);
-
-		if (lo & K8_INTP_C1E_ACTIVE_MASK) {
-			amd_e400_c1e_detected = true;
-			if (!boot_cpu_has(X86_FEATURE_NONSTOP_TSC))
-				mark_tsc_unstable("TSC halt in AMD C1E");
-			pr_info("System has AMD C1E enabled\n");
-		}
+	/*
+	 * We cannot use static_cpu_has_bug() here because X86_BUG_AMD_APIC_C1E
+	 * gets set after static_cpu_has() places have been converted via
+	 * alternatives.
+	 */
+	if (!boot_cpu_has_bug(X86_BUG_AMD_APIC_C1E)) {
+		default_idle();
+		return;
 	}
 
-	if (amd_e400_c1e_detected) {
-		int cpu = smp_processor_id();
+	tick_broadcast_enter();
 
-		if (!cpumask_test_cpu(cpu, amd_e400_c1e_mask)) {
-			cpumask_set_cpu(cpu, amd_e400_c1e_mask);
-			/* Force broadcast so ACPI can not interfere. */
-			tick_broadcast_force();
-			pr_info("Switch to broadcast mode on CPU%d\n", cpu);
-		}
-		tick_broadcast_enter();
-
-		default_idle();
+	default_idle();
 
-		/*
-		 * The switch back from broadcast mode needs to be
-		 * called with interrupts disabled.
-		 */
-		local_irq_disable();
-		tick_broadcast_exit();
-		local_irq_enable();
-	} else
-		default_idle();
+	/*
+	 * The switch back from broadcast mode needs to be called with
+	 * interrupts disabled.
+	 */
+	local_irq_disable();
+	tick_broadcast_exit();
+	local_irq_enable();
 }
 
 /*
@@ -448,8 +374,7 @@ void select_idle_routine(const struct cpuinfo_x86 *c)
 	if (x86_idle || boot_option_idle_override == IDLE_POLL)
 		return;
 
-	if (cpu_has_bug(c, X86_BUG_AMD_APIC_C1E)) {
-		/* E400: APIC timer interrupt does not wake up CPU from C1e */
+	if (boot_cpu_has_bug(X86_BUG_AMD_E400)) {
 		pr_info("using AMD E400 aware idle routine\n");
 		x86_idle = amd_e400_idle;
 	} else if (prefer_mwait_c1_over_halt(c)) {
@@ -459,11 +384,37 @@ void select_idle_routine(const struct cpuinfo_x86 *c)
 		x86_idle = default_idle;
 }
 
-void __init init_amd_e400_c1e_mask(void)
+void amd_e400_c1e_apic_setup(void)
+{
+	if (boot_cpu_has_bug(X86_BUG_AMD_APIC_C1E)) {
+		pr_info("Switch to broadcast mode on CPU%d\n", smp_processor_id());
+		local_irq_disable();
+		tick_broadcast_force();
+		local_irq_enable();
+	}
+}
+
+void __init arch_post_acpi_subsys_init(void)
 {
-	/* If we're using amd_e400_idle, we need to allocate amd_e400_c1e_mask. */
-	if (x86_idle == amd_e400_idle)
-		zalloc_cpumask_var(&amd_e400_c1e_mask, GFP_KERNEL);
+	u32 lo, hi;
+
+	if (!boot_cpu_has_bug(X86_BUG_AMD_E400))
+		return;
+
+	/*
+	 * AMD E400 detection needs to happen after ACPI has been enabled. If
+	 * the machine is affected K8_INTP_C1E_ACTIVE_MASK bits are set in
+	 * MSR_K8_INT_PENDING_MSG.
+	 */
+	rdmsr(MSR_K8_INT_PENDING_MSG, lo, hi);
+	if (!(lo & K8_INTP_C1E_ACTIVE_MASK))
+		return;
+
+	boot_cpu_set_bug(X86_BUG_AMD_APIC_C1E);
+
+	if (!boot_cpu_has(X86_FEATURE_NONSTOP_TSC))
+		mark_tsc_unstable("TSC halt in AMD C1E");
+	pr_info("System has AMD C1E enabled\n");
 }
 
 static int __init idle_setup(char *str)
diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index f854404be1c6..d0d744108594 100644
--- a/arch/x86/kernel/process_32.c
+++ b/arch/x86/kernel/process_32.c
@@ -49,7 +49,6 @@
 
 #include <asm/tlbflush.h>
 #include <asm/cpu.h>
-#include <asm/idle.h>
 #include <asm/syscalls.h>
 #include <asm/debugreg.h>
 #include <asm/switch_to.h>
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index 6c1b43eab80c..a76b65e3e615 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -44,7 +44,6 @@
 #include <asm/desc.h>
 #include <asm/proto.h>
 #include <asm/ia32.h>
-#include <asm/idle.h>
 #include <asm/syscalls.h>
 #include <asm/debugreg.h>
 #include <asm/switch_to.h>
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 2a501abe5000..0c37d4fd01b2 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -58,7 +58,6 @@
 #include <asm/desc.h>
 #include <asm/nmi.h>
 #include <asm/irq.h>
-#include <asm/idle.h>
 #include <asm/realmode.h>
 #include <asm/cpu.h>
 #include <asm/numa.h>
@@ -1596,7 +1595,6 @@ void play_dead_common(void)
 {
 	idle_task_exit();
 	reset_lazy_tlbstate();
-	amd_e400_remove_cpu(raw_smp_processor_id());
 
 	/* Ack it */
 	(void)cpu_report_death();