Because of the guest CPUID information may diffrent with
with host(some bits may mask off in guest) so introduce a
new function pt_cap_get_ex() to get the capability of Intel PT.
Signed-off-by: Luwei Kang <luwei.kang@xxxxxxxxx>
---
arch/x86/events/intel/pt.c | 10 ++++++++++
arch/x86/include/asm/intel_pt.h | 2 ++
2 files changed, 12 insertions(+)
diff --git a/arch/x86/events/intel/pt.c b/arch/x86/events/intel/pt.c
index d89dd8c..817104e 100644
--- a/arch/x86/events/intel/pt.c
+++ b/arch/x86/events/intel/pt.c
@@ -86,6 +86,16 @@ u32 pt_cap_get(enum pt_capabilities cap)
}
EXPORT_SYMBOL_GPL(pt_cap_get);
+u32 pt_cap_get_ex(u32 *caps, enum pt_capabilities cap)
+{
+ struct pt_cap_desc *cd = &pt_caps[cap];
+ u32 c = caps[cd->leaf * PT_CPUID_REGS_NUM + cd->reg];
+ unsigned int shift = __ffs(cd->mask);
+
+ return (c & cd->mask) >> shift;
+}
+EXPORT_SYMBOL_GPL(pt_cap_get_ex);
+
static ssize_t pt_cap_show(struct device *cdev,
struct device_attribute *attr,
char *buf)
diff --git a/arch/x86/include/asm/intel_pt.h b/arch/x86/include/asm/intel_pt.h
index 2de4db0..486e11f 100644
--- a/arch/x86/include/asm/intel_pt.h
+++ b/arch/x86/include/asm/intel_pt.h
@@ -27,9 +27,11 @@ enum pt_capabilities {
#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_CPU_SUP_INTEL)
void cpu_emergency_stop_pt(void);
extern u32 pt_cap_get(enum pt_capabilities cap);
+extern u32 pt_cap_get_ex(u32 *caps, enum pt_capabilities cap);
#else
static inline void cpu_emergency_stop_pt(void) {}
static inline u32 pt_cap_get(enum pt_capabilities cap) { return 0; }
+static u32 pt_cap_get_ex(u32 *caps, enum pt_capabilities cap) { return 0; }
#endif
#endif /* _ASM_X86_INTEL_PT_H */
--
1.8.3.1
