x86: provide paravirtualized hook for rdtscp

This patch adds a field in pv_cpu_ops for a paravirtualized hook
for rdtscp, needed for x86_64.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

2 files changed, 23 insertions, 0 deletions

diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index 1a170877f46c..072c1a08efe6 100644
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -374,6 +374,7 @@ struct pv_cpu_ops pv_cpu_ops = {
         .write_msr = native_write_msr_safe,
         .read_tsc = native_read_tsc,
         .read_pmc = native_read_pmc,
+        .read_tscp = native_read_tscp,
         .load_tr_desc = native_load_tr_desc,
         .set_ldt = native_set_ldt,
         .load_gdt = native_load_gdt,
diff --git a/include/asm-x86/paravirt.h b/include/asm-x86/paravirt.h
index 66290f58e939..8f7984319c30 100644
--- a/include/asm-x86/paravirt.h
+++ b/include/asm-x86/paravirt.h
@@ -120,6 +120,7 @@ struct pv_cpu_ops {
 
         u64 (*read_tsc)(void);
         u64 (*read_pmc)(int counter);
+        unsigned long long (*read_tscp)(unsigned int *aux);
 
         /* These two are jmp to, not actually called. */
         void (*irq_enable_syscall_ret)(void);
@@ -668,6 +669,27 @@ static inline unsigned long long paravirt_read_pmc(int counter)
         high = _l >> 32;                        \
 } while(0)
 
+static inline unsigned long long paravirt_rdtscp(unsigned int *aux)
+{
+        return PVOP_CALL1(u64, pv_cpu_ops.read_tscp, aux);
+}
+
+#define rdtscp(low, high, aux)                          \
+do {                                                    \
+        int __aux;                                      \
+        unsigned long __val = paravirt_rdtscp(&__aux);  \
+        (low) = (u32)__val;                             \
+        (high) = (u32)(__val >> 32);                    \
+        (aux) = __aux;                                  \
+} while (0)
+
+#define rdtscpll(val, aux)                              \
+do {                                                    \
+        unsigned long __aux;                            \
+        val = paravirt_rdtscp(&__aux);                  \
+        (aux) = __aux;                                  \
+} while (0)
+
 static inline void load_TR_desc(void)
 {
         PVOP_VCALL0(pv_cpu_ops.load_tr_desc);