clock: output clock description in metadata

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

diff --git a/wrapper/trace-clock.h b/wrapper/trace-clock.h
index 18cda2aa1355dc98306ab8fe3a1b24f2e9ecdb9b..1140b94bcd1de2ae292a5dc9c4f9ffd4653271aa 100644 (file)
--- a/wrapper/trace-clock.h
+++ b/wrapper/trace-clock.h
@@ -7,8 +7,8 @@
  * Dual LGPL v2.1/GPL v2 license.
  */
 
-#ifndef _LTT_TRACE_CLOCK_H
-#define _LTT_TRACE_CLOCK_H
+#ifndef _LTTNG_TRACE_CLOCK_H
+#define _LTTNG_TRACE_CLOCK_H
 
 #ifdef CONFIG_HAVE_TRACE_CLOCK
 #include <linux/trace-clock.h>
@@ -28,7 +28,7 @@ static inline u64 trace_clock_monotonic_wrapper(void)
         * nest over the xtime write seqlock and deadlock.
         */
        if (in_nmi())
-               return 0;
+               return (u64) -EIO;
 
        ktime = ktime_get();
        return (u64) ktime.tv64;
@@ -44,27 +44,30 @@ static inline u64 trace_clock_read64(void)
        return (u64) trace_clock_monotonic_wrapper();
 }
 
-static inline u64 trace_clock_frequency(void)
+static inline u64 trace_clock_freq(void)
 {
-       return (u64)NSEC_PER_SEC;
+       return (u64) NSEC_PER_SEC;
 }
 
-static inline u32 trace_clock_freq_scale(void)
+static inline const char *trace_clock_uuid(void)
 {
-       return 1;
+       return "CLOCK_MONOTONIC";
 }
 
 static inline int get_trace_clock(void)
 {
+       /*
+        * LTTng: Using mainline kernel monotonic clock. NMIs will not be
+        * traced, and expect significant performance degradation compared to
+        * the LTTng trace clocks. Integration of the LTTng 0.x trace clocks
+        * into LTTng 2.0 is planned in a near future.
+        */
        printk(KERN_WARNING "LTTng: Using mainline kernel monotonic clock.\n");
        printk(KERN_WARNING "  * NMIs will not be traced,\n");
        printk(KERN_WARNING "  * expect significant performance degradation compared to the\n");
        printk(KERN_WARNING "    LTTng trace clocks.\n");
-       printk(KERN_WARNING "You should consider deploying a kernel with the the LTTng kernel\n");
-       printk(KERN_WARNING "patches, or, better, ask the Linux tracing maintainers to integrate\n");
-       printk(KERN_WARNING "them if you care deeply about this.\n");
-
-#warning "LTTng: Using mainline kernel monotonic clock. NMIs will not be traced, and expect significant performance degradation compared to the LTTng trace clocks. You should consider deploying a kernel with the the LTTng kernel patches, or, better, ask the Linux tracing maintainers to integrate them if you care deeply about this."
+       printk(KERN_WARNING "Integration of the LTTng 0.x trace clocks into LTTng 2.0 is planned\n");
+       printk(KERN_WARNING "in a near future.\n");
 
        return 0;
 }
@@ -75,4 +78,4 @@ static inline void put_trace_clock(void)
 
 #endif /* CONFIG_HAVE_TRACE_CLOCK */
 
-#endif /* _LTT_TRACE_CLOCK_H */
+#endif /* _LTTNG_TRACE_CLOCK_H */