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

…ux/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
kyagi · Dec 12, 2016 · 212f300 · 212f300
2 parents 6f3be0f + 34bc356
commit 212f300
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Showing 32 changed files with 74 additions and 803 deletions.
diff --git a/MAINTAINERS b/MAINTAINERS
@@ -6104,12 +6104,6 @@ S:	Maintained
 F:	Documentation/cdrom/ide-cd
 F:	drivers/ide/ide-cd*
 
-IDLE-I7300
-M:	Andy Henroid <[email protected]>
-L:	[email protected]
-S:	Supported
-F:	drivers/idle/i7300_idle.c
-
 IEEE 802.15.4 SUBSYSTEM
 M:	Alexander Aring <[email protected]>
 M:	Stefan Schmidt <[email protected]>

diff --git a/arch/x86/include/asm/acpi.h b/arch/x86/include/asm/acpi.h
@@ -94,7 +94,7 @@ static inline unsigned int acpi_processor_cstate_check(unsigned int max_cstate)
 	    boot_cpu_data.x86_model <= 0x05 &&
 	    boot_cpu_data.x86_mask < 0x0A)
 		return 1;
-	else if (amd_e400_c1e_detected)
+	else if (boot_cpu_has(X86_BUG_AMD_APIC_C1E))
 		return 1;
 	else
 		return max_cstate;

diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h
@@ -11,7 +11,6 @@
 #include <asm/fixmap.h>
 #include <asm/mpspec.h>
 #include <asm/msr.h>
-#include <asm/idle.h>
 
 #define ARCH_APICTIMER_STOPS_ON_C3	1
 
@@ -640,7 +639,6 @@ extern void irq_exit(void);
 static inline void entering_irq(void)
 {
 	irq_enter();
-	exit_idle();
 }
 
 static inline void entering_ack_irq(void)

diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h
@@ -204,6 +204,7 @@ static __always_inline __pure bool _static_cpu_has(u16 bit)
 
 #define static_cpu_has_bug(bit)		static_cpu_has((bit))
 #define boot_cpu_has_bug(bit)		cpu_has_bug(&boot_cpu_data, (bit))
+#define boot_cpu_set_bug(bit)		set_cpu_cap(&boot_cpu_data, (bit))
 
 #define MAX_CPU_FEATURES		(NCAPINTS * 32)
 #define cpu_have_feature		boot_cpu_has

diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
@@ -314,4 +314,6 @@
 #define X86_BUG_NULL_SEG	X86_BUG(10) /* Nulling a selector preserves the base */
 #define X86_BUG_SWAPGS_FENCE	X86_BUG(11) /* SWAPGS without input dep on GS */
 #define X86_BUG_MONITOR		X86_BUG(12) /* IPI required to wake up remote CPU */
+#define X86_BUG_AMD_E400	X86_BUG(13) /* CPU is among the affected by Erratum 400 */
+
 #endif /* _ASM_X86_CPUFEATURES_H */
diff --git a/arch/x86/include/asm/idle.h b/arch/x86/include/asm/idle.h
diff --git a/arch/x86/include/asm/percpu.h b/arch/x86/include/asm/percpu.h
@@ -507,17 +507,6 @@ do {									\
 
 #endif
 
-/* This is not atomic against other CPUs -- CPU preemption needs to be off */
-#define x86_test_and_clear_bit_percpu(bit, var)				\
-({									\
-	bool old__;							\
-	asm volatile("btr %2,"__percpu_arg(1)"\n\t"			\
-		     CC_SET(c)						\
-		     : CC_OUT(c) (old__), "+m" (var)			\
-		     : "dIr" (bit));					\
-	old__;								\
-})
-
 static __always_inline bool x86_this_cpu_constant_test_bit(unsigned int nr,
                         const unsigned long __percpu *addr)
 {

diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
@@ -633,10 +633,9 @@ static inline void sync_core(void)
 }
 
 extern void select_idle_routine(const struct cpuinfo_x86 *c);
-extern void init_amd_e400_c1e_mask(void);
+extern void amd_e400_c1e_apic_setup(void);
 
 extern unsigned long		boot_option_idle_override;
-extern bool			amd_e400_c1e_detected;
 
 enum idle_boot_override {IDLE_NO_OVERRIDE=0, IDLE_HALT, IDLE_NOMWAIT,
 			 IDLE_POLL};

diff --git 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
@@ -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
@@ -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
@@ -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
@@ -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
@@ -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
@@ -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
@@ -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
@@ -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
@@ -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
@@ -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;