1 files changed, 17 insertions, 13 deletions

diff --git a/arch/x86/kernel/tsc_sync.c b/arch/x86/kernel/tsc_sync.c
index 9125efe66a0..0577825cf89 100644
--- a/arch/x86/kernel/tsc_sync.c
+++ b/arch/x86/kernel/tsc_sync.c
@@ -46,7 +46,7 @@ static __cpuinit void check_tsc_warp(void)
         cycles_t start, now, prev, end;
         int i;
 
-        start = get_cycles_sync();
+        start = get_cycles();
         /*
          * The measurement runs for 20 msecs:
          */
@@ -61,18 +61,18 @@ static __cpuinit void check_tsc_warp(void)
                  */
                 __raw_spin_lock(&sync_lock);
                 prev = last_tsc;
-                now = get_cycles_sync();
+                now = get_cycles();
                 last_tsc = now;
                 __raw_spin_unlock(&sync_lock);
 
                 /*
                  * Be nice every now and then (and also check whether
-                 * measurement is done [we also insert a 100 million
+                 * measurement is done [we also insert a 10 million
                  * loops safety exit, so we dont lock up in case the
                  * TSC readout is totally broken]):
                  */
                 if (unlikely(!(i & 7))) {
-                        if (now > end || i > 100000000)
+                        if (now > end || i > 10000000)
                                 break;
                         cpu_relax();
                         touch_nmi_watchdog();
@@ -87,7 +87,11 @@ static __cpuinit void check_tsc_warp(void)
                         nr_warps++;
                         __raw_spin_unlock(&sync_lock);
                 }
-
+        }
+        if (!(now-start)) {
+                printk("Warning: zero tsc calibration delta: %Ld [max: %Ld]\n",
+                        now-start, end-start);
+                WARN_ON(1);
         }
 }
 
@@ -129,24 +133,24 @@ void __cpuinit check_tsc_sync_source(int cpu)
         while (atomic_read(&stop_count) != cpus-1)
                 cpu_relax();
 
-        /*
-         * Reset it - just in case we boot another CPU later:
-         */
-        atomic_set(&start_count, 0);
-
         if (nr_warps) {
                 printk("\n");
                 printk(KERN_WARNING "Measured %Ld cycles TSC warp between CPUs,"
                                     " turning off TSC clock.\n", max_warp);
                 mark_tsc_unstable("check_tsc_sync_source failed");
-                nr_warps = 0;
-                max_warp = 0;
-                last_tsc = 0;
         } else {
                 printk(" passed.\n");
         }
 
         /*
+         * Reset it - just in case we boot another CPU later:
+         */
+        atomic_set(&start_count, 0);
+        nr_warps = 0;
+        max_warp = 0;
+        last_tsc = 0;
+
+        /*
          * Let the target continue with the bootup:
          */
         atomic_inc(&stop_count);