3 files changed, 30 insertions, 7 deletions

diff --git a/arch/x86/oprofile/init.c b/arch/x86/oprofile/init.c
index cdfe4c54deca..f148cf652678 100644
--- a/arch/x86/oprofile/init.c
+++ b/arch/x86/oprofile/init.c
@@ -21,6 +21,7 @@ extern int op_nmi_timer_init(struct oprofile_operations *ops);
 extern void op_nmi_exit(void);
 extern void x86_backtrace(struct pt_regs * const regs, unsigned int depth);
 
+static int nmi_timer;
 
 int __init oprofile_arch_init(struct oprofile_operations *ops)
 {
@@ -31,8 +32,9 @@ int __init oprofile_arch_init(struct oprofile_operations *ops)
 #ifdef CONFIG_X86_LOCAL_APIC
         ret = op_nmi_init(ops);
 #endif
+        nmi_timer = (ret != 0);
 #ifdef CONFIG_X86_IO_APIC
-        if (ret < 0)
+        if (nmi_timer)
                 ret = op_nmi_timer_init(ops);
 #endif
         ops->backtrace = x86_backtrace;
@@ -44,6 +46,7 @@ int __init oprofile_arch_init(struct oprofile_operations *ops)
 void oprofile_arch_exit(void)
 {
 #ifdef CONFIG_X86_LOCAL_APIC
-        op_nmi_exit();
+        if (!nmi_timer)
+                op_nmi_exit();
 #endif
 }
diff --git a/drivers/oprofile/oprof.c b/drivers/oprofile/oprof.c
index dccd8636095c..f8c752e408a6 100644
--- a/drivers/oprofile/oprof.c
+++ b/drivers/oprofile/oprof.c
@@ -239,26 +239,45 @@ int oprofile_set_ulong(unsigned long *addr, unsigned long val)
         return err;
 }
 
+static int timer_mode;
+
 static int __init oprofile_init(void)
 {
         int err;
 
+        /* always init architecture to setup backtrace support */
         err = oprofile_arch_init(&oprofile_ops);
-        if (err < 0 || timer) {
-                printk(KERN_INFO "oprofile: using timer interrupt.\n");
+
+        timer_mode = err || timer;      /* fall back to timer mode on errors */
+        if (timer_mode) {
+                if (!err)
+                        oprofile_arch_exit();
                 err = oprofile_timer_init(&oprofile_ops);
                 if (err)
                         return err;
         }
-        return oprofilefs_register();
+
+        err = oprofilefs_register();
+        if (!err)
+                return 0;
+
+        /* failed */
+        if (timer_mode)
+                oprofile_timer_exit();
+        else
+                oprofile_arch_exit();
+
+        return err;
 }
 
 
 static void __exit oprofile_exit(void)
 {
-        oprofile_timer_exit();
         oprofilefs_unregister();
-        oprofile_arch_exit();
+        if (timer_mode)
+                oprofile_timer_exit();
+        else
+                oprofile_arch_exit();
 }
 
 
diff --git a/drivers/oprofile/timer_int.c b/drivers/oprofile/timer_int.c
index 3ef44624f510..878fba126582 100644
--- a/drivers/oprofile/timer_int.c
+++ b/drivers/oprofile/timer_int.c
@@ -110,6 +110,7 @@ int oprofile_timer_init(struct oprofile_operations *ops)
         ops->start = oprofile_hrtimer_start;
         ops->stop = oprofile_hrtimer_stop;
         ops->cpu_type = "timer";
+        printk(KERN_INFO "oprofile: using timer interrupt.\n");
         return 0;
 }