[PATCH 04/15] provide paravirtualized hook for rdtscp

Glauber de Oliveira Costa
2007-12-20T20:09:32Z

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>
---
arch/x86/kernel/paravirt.c | 1 +
include/asm-x86/paravirt.h | 22 ++++++++++++++++++++++
2 files changed, 23 insertions(+), 0 deletions(-)

Index: linux-2.6-x86/arch/x86/kernel/paravirt.c
===================================================================
--- linux-2.6-x86.orig/arch/x86/kernel/paravirt.c 2007-12-20 19:07:15.000000000 -0800
+++ linux-2.6-x86/arch/x86/kernel/paravirt.c 2007-12-20 19:07:22.000000000 -0800
@@ -374,6 +374,7 @@
.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,
Index: linux-2.6-x86/include/asm-x86/paravirt.h
===================================================================
--- linux-2.6-x86.orig/include/asm-x86/paravirt.h 2007-12-20 19:07:18.000000000 -0800
+++ linux-2.6-x86/include/asm-x86/paravirt.h 2007-12-20 19:07:22.000000000 -0800
@@ -120,6 +120,7 @@

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 @@
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);