4 files changed, 77 insertions, 13 deletions

diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h
index f6d43dbfd8e7..254883d0c7e0 100644
--- a/arch/x86/include/asm/perf_event.h
+++ b/arch/x86/include/asm/perf_event.h
@@ -135,17 +135,10 @@ extern void perf_events_lapic_init(void);
  */
 #define PERF_EFLAGS_EXACT       (1UL << 3)
 
-#define perf_misc_flags(regs)                           \
-({      int misc = 0;                                   \
-        if (user_mode(regs))                            \
-                misc |= PERF_RECORD_MISC_USER;          \
-        else                                            \
-                misc |= PERF_RECORD_MISC_KERNEL;        \
-        if (regs->flags & PERF_EFLAGS_EXACT)            \
-                misc |= PERF_RECORD_MISC_EXACT;         \
-        misc; })
-
-#define perf_instruction_pointer(regs)  ((regs)->ip)
+struct pt_regs;
+extern unsigned long perf_instruction_pointer(struct pt_regs *regs);
+extern unsigned long perf_misc_flags(struct pt_regs *regs);
+#define perf_misc_flags(regs)   perf_misc_flags(regs)
 
 #else
 static inline void init_hw_perf_events(void)            { }
diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index 626154a9f535..2ea78abf69d9 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -1720,6 +1720,11 @@ struct perf_callchain_entry *perf_callchain(struct pt_regs *regs)
 {
         struct perf_callchain_entry *entry;
 
+        if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) {
+                /* TODO: We don't support guest os callchain now */
+                return NULL;
+        }
+
         if (in_nmi())
                 entry = &__get_cpu_var(pmc_nmi_entry);
         else
@@ -1743,3 +1748,29 @@ void perf_arch_fetch_caller_regs(struct pt_regs *regs, unsigned long ip, int ski
         regs->cs = __KERNEL_CS;
         local_save_flags(regs->flags);
 }
+
+unsigned long perf_instruction_pointer(struct pt_regs *regs)
+{
+        unsigned long ip;
+        if (perf_guest_cbs && perf_guest_cbs->is_in_guest())
+                ip = perf_guest_cbs->get_guest_ip();
+        else
+                ip = instruction_pointer(regs);
+        return ip;
+}
+
+unsigned long perf_misc_flags(struct pt_regs *regs)
+{
+        int misc = 0;
+        if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) {
+                misc |= perf_guest_cbs->is_user_mode() ?
+                        PERF_RECORD_MISC_GUEST_USER :
+                        PERF_RECORD_MISC_GUEST_KERNEL;
+        } else
+                misc |= user_mode(regs) ? PERF_RECORD_MISC_USER :
+                        PERF_RECORD_MISC_KERNEL;
+        if (regs->flags & PERF_EFLAGS_EXACT)
+                misc |= PERF_RECORD_MISC_EXACT;
+
+        return misc;
+}
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index bf896d0b2e9c..24de5f181a41 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -288,11 +288,13 @@ struct perf_event_mmap_page {
         __u64   data_tail;              /* user-space written tail */
 };
 
-#define PERF_RECORD_MISC_CPUMODE_MASK           (3 << 0)
+#define PERF_RECORD_MISC_CPUMODE_MASK           (7 << 0)
 #define PERF_RECORD_MISC_CPUMODE_UNKNOWN        (0 << 0)
 #define PERF_RECORD_MISC_KERNEL                 (1 << 0)
 #define PERF_RECORD_MISC_USER                   (2 << 0)
 #define PERF_RECORD_MISC_HYPERVISOR             (3 << 0)
+#define PERF_RECORD_MISC_GUEST_KERNEL           (4 << 0)
+#define PERF_RECORD_MISC_GUEST_USER             (5 << 0)
 
 #define PERF_RECORD_MISC_EXACT                  (1 << 14)
 /*
@@ -446,6 +448,12 @@ enum perf_callchain_context {
 # include <asm/perf_event.h>
 #endif
 
+struct perf_guest_info_callbacks {
+        int (*is_in_guest) (void);
+        int (*is_user_mode) (void);
+        unsigned long (*get_guest_ip) (void);
+};
+
 #ifdef CONFIG_HAVE_HW_BREAKPOINT
 #include <asm/hw_breakpoint.h>
 #endif
@@ -932,6 +940,12 @@ static inline void perf_event_mmap(struct vm_area_struct *vma)
                 __perf_event_mmap(vma);
 }
 
+extern struct perf_guest_info_callbacks *perf_guest_cbs;
+extern int perf_register_guest_info_callbacks(
+                struct perf_guest_info_callbacks *);
+extern int perf_unregister_guest_info_callbacks(
+                struct perf_guest_info_callbacks *);
+
 extern void perf_event_comm(struct task_struct *tsk);
 extern void perf_event_fork(struct task_struct *tsk);
 
@@ -1001,6 +1015,11 @@ perf_sw_event(u32 event_id, u64 nr, int nmi,
 static inline void
 perf_bp_event(struct perf_event *event, void *data)                     { }
 
+static inline int perf_register_guest_info_callbacks
+(struct perf_guest_info_callbacks *) {return 0; }
+static inline int perf_unregister_guest_info_callbacks
+(struct perf_guest_info_callbacks *) {return 0; }
+
 static inline void perf_event_mmap(struct vm_area_struct *vma)          { }
 static inline void perf_event_comm(struct task_struct *tsk)             { }
 static inline void perf_event_fork(struct task_struct *tsk)             { }
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 07b7a435bf03..9dbe8cdaf145 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -2798,6 +2798,27 @@ void perf_arch_fetch_caller_regs(struct pt_regs *regs, unsigned long ip, int ski
 
 
 /*
+ * We assume there is only KVM supporting the callbacks.
+ * Later on, we might change it to a list if there is
+ * another virtualization implementation supporting the callbacks.
+ */
+struct perf_guest_info_callbacks *perf_guest_cbs;
+
+int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs)
+{
+        perf_guest_cbs = cbs;
+        return 0;
+}
+EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks);
+
+int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs)
+{
+        perf_guest_cbs = NULL;
+        return 0;
+}
+EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks);
+
+/*
  * Output
  */
 static bool perf_output_space(struct perf_mmap_data *data, unsigned long tail,
@@ -3749,7 +3770,7 @@ void __perf_event_mmap(struct vm_area_struct *vma)
                 .event_id  = {
                         .header = {
                                 .type = PERF_RECORD_MMAP,
-                                .misc = 0,
+                                .misc = PERF_RECORD_MISC_USER,
                                 /* .size */
                         },
                         /* .pid */