Merge tag 'sched-urgent-2021-05-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler fixes from Ingo Molnar:
 "Fix an idle CPU selection bug, and an AMD Ryzen maximum frequency
  enumeration bug"

* tag 'sched-urgent-2021-05-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, sched: Fix the AMD CPPC maximum performance value on certain AMD Ryzen generations
  sched/fair: Fix clearing of has_idle_cores flag in select_idle_cpu()

Author: torvalds

arch/x86/include/asm/processor.h

@@ -787,8 +787,10 @@ DECLARE_PER_CPU(u64, msr_misc_features_shadow);
 
 #ifdef CONFIG_CPU_SUP_AMD
 extern u32 amd_get_nodes_per_socket(void);
+extern u32 amd_get_highest_perf(void);
 #else
 static inline u32 amd_get_nodes_per_socket(void)	{ return 0; }
+static inline u32 amd_get_highest_perf(void)		{ return 0; }
 #endif
 
 static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves)

arch/x86/kernel/cpu/amd.c

@@ -1165,3 +1165,19 @@ void set_dr_addr_mask(unsigned long mask, int dr)
 		break;
 	}
 }
+
+u32 amd_get_highest_perf(void)
+{
+	struct cpuinfo_x86 *c = &boot_cpu_data;
+
+	if (c->x86 == 0x17 && ((c->x86_model >= 0x30 && c->x86_model < 0x40) ||
+			       (c->x86_model >= 0x70 && c->x86_model < 0x80)))
+		return 166;
+
+	if (c->x86 == 0x19 && ((c->x86_model >= 0x20 && c->x86_model < 0x30) ||
+			       (c->x86_model >= 0x40 && c->x86_model < 0x70)))
+		return 166;
+
+	return 255;
+}
+EXPORT_SYMBOL_GPL(amd_get_highest_perf);

arch/x86/kernel/smpboot.c

@@ -2043,7 +2043,7 @@ static bool amd_set_max_freq_ratio(void)
 		return false;
 	}
 
-	highest_perf = perf_caps.highest_perf;
+	highest_perf = amd_get_highest_perf();
 	nominal_perf = perf_caps.nominal_perf;
 
 	if (!highest_perf || !nominal_perf) {

drivers/cpufreq/acpi-cpufreq.c

@@ -646,7 +646,11 @@ static u64 get_max_boost_ratio(unsigned int cpu)
 		return 0;
 	}
 
-	highest_perf = perf_caps.highest_perf;
+	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
+		highest_perf = amd_get_highest_perf();
+	else
+		highest_perf = perf_caps.highest_perf;
+
 	nominal_perf = perf_caps.nominal_perf;
 
 	if (!highest_perf || !nominal_perf) {

kernel/sched/fair.c

@@ -6217,7 +6217,7 @@ static int select_idle_cpu(struct task_struct *p, struct sched_domain *sd, bool
 	}
 
 	if (has_idle_core)
-		set_idle_cores(this, false);
+		set_idle_cores(target, false);
 
 	if (sched_feat(SIS_PROP) && !has_idle_core) {
 		time = cpu_clock(this) - time;