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Diffstat (limited to 'arch/x86/kernel/smpboot.c')
-rw-r--r--arch/x86/kernel/smpboot.c72
1 files changed, 59 insertions, 13 deletions
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index d6cf1e23c2a3..fc78c2325fd2 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -64,7 +64,7 @@
#include <asm/acpi.h>
#include <asm/cacheinfo.h>
-#include <asm/cpuid.h>
+#include <asm/cpuid/api.h>
#include <asm/desc.h>
#include <asm/nmi.h>
#include <asm/irq.h>
@@ -695,7 +695,7 @@ static void send_init_sequence(u32 phys_apicid)
/*
* Wake up AP by INIT, INIT, STARTUP sequence.
*/
-static int wakeup_secondary_cpu_via_init(u32 phys_apicid, unsigned long start_eip)
+static int wakeup_secondary_cpu_via_init(u32 phys_apicid, unsigned long start_eip, unsigned int cpu)
{
unsigned long send_status = 0, accept_status = 0;
int num_starts, j, maxlvt;
@@ -842,7 +842,7 @@ int common_cpu_up(unsigned int cpu, struct task_struct *idle)
* Returns zero if startup was successfully sent, else error code from
* ->wakeup_secondary_cpu.
*/
-static int do_boot_cpu(u32 apicid, int cpu, struct task_struct *idle)
+static int do_boot_cpu(u32 apicid, unsigned int cpu, struct task_struct *idle)
{
unsigned long start_ip = real_mode_header->trampoline_start;
int ret;
@@ -896,11 +896,11 @@ static int do_boot_cpu(u32 apicid, int cpu, struct task_struct *idle)
* - Use an INIT boot APIC message
*/
if (apic->wakeup_secondary_cpu_64)
- ret = apic->wakeup_secondary_cpu_64(apicid, start_ip);
+ ret = apic->wakeup_secondary_cpu_64(apicid, start_ip, cpu);
else if (apic->wakeup_secondary_cpu)
- ret = apic->wakeup_secondary_cpu(apicid, start_ip);
+ ret = apic->wakeup_secondary_cpu(apicid, start_ip, cpu);
else
- ret = wakeup_secondary_cpu_via_init(apicid, start_ip);
+ ret = wakeup_secondary_cpu_via_init(apicid, start_ip, cpu);
/* If the wakeup mechanism failed, cleanup the warm reset vector */
if (ret)
@@ -1188,6 +1188,12 @@ void cpu_disable_common(void)
remove_siblinginfo(cpu);
+ /*
+ * Stop allowing kernel-mode FPU. This is needed so that if the CPU is
+ * brought online again, the initial state is not allowed:
+ */
+ this_cpu_write(kernel_fpu_allowed, false);
+
/* It's now safe to remove this processor from the online map */
lock_vector_lock();
remove_cpu_from_maps(cpu);
@@ -1238,10 +1244,6 @@ void play_dead_common(void)
local_irq_disable();
}
-/*
- * We need to flush the caches before going to sleep, lest we have
- * dirty data in our caches when we come back up.
- */
void __noreturn mwait_play_dead(unsigned int eax_hint)
{
struct mwait_cpu_dead *md = this_cpu_ptr(&mwait_cpu_dead);
@@ -1288,6 +1290,50 @@ void __noreturn mwait_play_dead(unsigned int eax_hint)
}
/*
+ * We need to flush the caches before going to sleep, lest we have
+ * dirty data in our caches when we come back up.
+ */
+static inline void mwait_play_dead_cpuid_hint(void)
+{
+ unsigned int eax, ebx, ecx, edx;
+ unsigned int highest_cstate = 0;
+ unsigned int highest_subcstate = 0;
+ int i;
+
+ 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;
+ if (!this_cpu_has(X86_FEATURE_CLFLUSH))
+ return;
+
+ eax = CPUID_LEAF_MWAIT;
+ ecx = 0;
+ native_cpuid(&eax, &ebx, &ecx, &edx);
+
+ /*
+ * eax will be 0 if EDX enumeration is not valid.
+ * Initialized below to cstate, sub_cstate value when EDX is valid.
+ */
+ if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED)) {
+ eax = 0;
+ } else {
+ edx >>= MWAIT_SUBSTATE_SIZE;
+ for (i = 0; i < 7 && edx; i++, edx >>= MWAIT_SUBSTATE_SIZE) {
+ if (edx & MWAIT_SUBSTATE_MASK) {
+ highest_cstate = i;
+ highest_subcstate = edx & MWAIT_SUBSTATE_MASK;
+ }
+ }
+ eax = (highest_cstate << MWAIT_SUBSTATE_SIZE) |
+ (highest_subcstate - 1);
+ }
+
+ mwait_play_dead(eax);
+}
+
+/*
* Kick all "offline" CPUs out of mwait on kexec(). See comment in
* mwait_play_dead().
*/
@@ -1337,9 +1383,9 @@ void native_play_dead(void)
play_dead_common();
tboot_shutdown(TB_SHUTDOWN_WFS);
- /* Below returns only on error. */
- cpuidle_play_dead();
- hlt_play_dead();
+ mwait_play_dead_cpuid_hint();
+ if (cpuidle_play_dead())
+ hlt_play_dead();
}
#else /* ... !CONFIG_HOTPLUG_CPU */