x86: apic: Track APIC ops on a per-cpu basis
Track the virtual function table to handle xAPIC vs. x2APIC on a per-cpu
basis. Using a common global is racy as nothing in KUT synchronizes
CPUs when switching to/from x2APIC.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220121231852.1439917-8-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/lib/x86/apic.c b/lib/x86/apic.c
index 44a6ad3..d7137b6 100644
--- a/lib/x86/apic.c
+++ b/lib/x86/apic.c
@@ -2,6 +2,7 @@
#include "apic.h"
#include "msr.h"
#include "processor.h"
+#include "smp.h"
#include "asm/barrier.h"
void *g_apic = (void *)0xfee00000;
@@ -15,6 +16,11 @@
u32 (*id)(void);
};
+static struct apic_ops *get_apic_ops(void)
+{
+ return this_cpu_read_apic_ops();
+}
+
static void outb(unsigned char data, unsigned short port)
{
asm volatile ("out %0, %1" : : "a"(data), "d"(port));
@@ -60,8 +66,6 @@
.id = xapic_id,
};
-static const struct apic_ops *apic_ops = &xapic_ops;
-
static u32 x2apic_read(unsigned reg)
{
unsigned a, d;
@@ -96,12 +100,12 @@
u32 apic_read(unsigned reg)
{
- return apic_ops->reg_read(reg);
+ return get_apic_ops()->reg_read(reg);
}
void apic_write(unsigned reg, u32 val)
{
- apic_ops->reg_write(reg, val);
+ get_apic_ops()->reg_write(reg, val);
}
bool apic_read_bit(unsigned reg, int n)
@@ -113,12 +117,12 @@
void apic_icr_write(u32 val, u32 dest)
{
- apic_ops->icr_write(val, dest);
+ get_apic_ops()->icr_write(val, dest);
}
uint32_t apic_id(void)
{
- return apic_ops->id();
+ return get_apic_ops()->id();
}
uint8_t apic_get_tpr(void)
@@ -152,7 +156,7 @@
asm ("rdmsr" : "=a"(a), "=d"(d) : "c"(MSR_IA32_APICBASE));
a |= 1 << 10;
asm ("wrmsr" : : "a"(a), "d"(d), "c"(MSR_IA32_APICBASE));
- apic_ops = &x2apic_ops;
+ this_cpu_write_apic_ops((void *)&x2apic_ops);
return 1;
} else {
return 0;
@@ -162,7 +166,7 @@
void disable_apic(void)
{
wrmsr(MSR_IA32_APICBASE, rdmsr(MSR_IA32_APICBASE) & ~(APIC_EN | APIC_EXTD));
- apic_ops = &xapic_ops;
+ this_cpu_write_apic_ops((void *)&xapic_ops);
}
void reset_apic(void)
diff --git a/lib/x86/smp.h b/lib/x86/smp.h
index eb037a4..bd303c2 100644
--- a/lib/x86/smp.h
+++ b/lib/x86/smp.h
@@ -15,6 +15,7 @@
};
uint32_t exception_data;
};
+ void *apic_ops;
};
#define typeof_percpu(name) typeof(((struct percpu_data *)0)->name)
@@ -66,6 +67,7 @@
BUILD_PERCPU_OP(exception_vector);
BUILD_PERCPU_OP(exception_rflags_rf);
BUILD_PERCPU_OP(exception_error_code);
+BUILD_PERCPU_OP(apic_ops);
void smp_init(void);
