Fix: show warning for broken clock work-around

[lttng-modules.git] / wrapper / trace-clock.h

diff --git a/wrapper/trace-clock.h b/wrapper/trace-clock.h
index 561094b3ae924a6545cf795f0ba838040c1273fe..05472dc1cebcb341970e2f659ca64f1cefc058fa 100644 (file)
--- a/wrapper/trace-clock.h
+++ b/wrapper/trace-clock.h
@@ -39,12 +39,25 @@
 #include "percpu-defs.h"
 #include "random.h"
 
-#if ((LTTNG_KERNEL_RANGE(3,10,0, 3,10,14) && !LTTNG_RHEL_KERNEL_RANGE(3,10,0,7,0, 3,10,14,0,0)) \
+#if ((LTTNG_KERNEL_RANGE(3,10,0, 3,10,14) && !LTTNG_RHEL_KERNEL_RANGE(3,10,0,123,0,0, 3,10,14,0,0,0)) \
        || LTTNG_KERNEL_RANGE(3,11,0, 3,11,3))
 #error "Linux kernels 3.10 and 3.11 introduce a deadlock in the timekeeping subsystem. Fixed by commit 7bd36014460f793c19e7d6c94dab67b0afcfcb7f \"timekeeping: Fix HRTICK related deadlock from ntp lock changes\" in Linux."
 #endif
 
-#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,17,0))
+/*
+ * Upstream Linux commit 27727df240c7 ("Avoid taking lock in NMI path with
+ * CONFIG_DEBUG_TIMEKEEPING") introduces a buggy ktime_get_mono_fast_ns().
+ * This is fixed by patch "timekeeping: Fix __ktime_get_fast_ns() regression".
+ */
+#if (LTTNG_KERNEL_RANGE(4,8,0, 4,8,1) \
+       || LTTNG_KERNEL_RANGE(4,7,4, 4,7,7) \
+       || LTTNG_KERNEL_RANGE(4,4,20, 4,4,24) \
+       || LTTNG_KERNEL_RANGE(4,1,32, 4,1,34))
+#define LTTNG_CLOCK_NMI_SAFE_BROKEN
+#endif
+
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,17,0) \
+       && !defined(LTTNG_CLOCK_NMI_SAFE_BROKEN))
 
 DECLARE_PER_CPU(local_t, lttng_last_tsc);