Privatize headers

[ust.git] / include / ust / clock.h

diff --git a/include/ust/clock.h b/include/ust/clock.h
index d4b6a9ddc1e2768a219beed14d0c6336b4d58b13..5e8f755b9c08573d1fd7ec110156fe3ea71bdaf4 100644 (file)
--- a/include/ust/clock.h
+++ b/include/ust/clock.h
@@ -15,11 +15,14 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
  */
 
-#ifndef UST_CLOCK_H
-#define UST_CLOCK_H
+#ifndef _UST_CLOCK_H
+#define _UST_CLOCK_H
 
+#include <time.h>
 #include <sys/time.h>
-#include <ust/kcompat/kcompat.h>
+#include <stdint.h>
+#include <stddef.h>
+#include <ust/core.h>
 
 /* TRACE CLOCK */
 
@@ -28,88 +31,73 @@
    - gettimeofday() clock
 
    Microbenchmarks on Linux 2.6.30 on Core2 Duo 3GHz (functions are inlined):
-     Calls (100000000) to tsc(): 4004035641 cycles or 40 cycles/call
-     Calls (100000000) to gettimeofday(): 9723158352 cycles or 97 cycles/call
+        Calls (100000000) to tsc(): 4004035641 cycles or 40 cycles/call
+        Calls (100000000) to gettimeofday(): 9723158352 cycles or 97 cycles/call
 
    For merging traces with the kernel, a time source compatible with that of
    the kernel is necessary.
 
+   Instead of gettimeofday(), we are now using clock_gettime for better
+   precision and monotonicity.
 */
 
-#define TRACE_CLOCK_GENERIC
-#ifdef TRACE_CLOCK_GENERIC
+/* Only available for x86 arch */
+#define CLOCK_TRACE_FREQ  14
+#define CLOCK_TRACE  15
+union lttng_timespec {
+       struct timespec ts;
+       uint64_t lttng_ts;
+};
 
-static __inline__ u64 trace_clock_read64(void)
-{
-       struct timeval tv;
-       u64 retval;
-
-       gettimeofday(&tv, NULL);
-       retval = tv.tv_sec;
-       retval *= 1000000;
-       retval += tv.tv_usec;
+extern int ust_clock_source;
 
-       return retval;
-}
+/* Choosing correct trace clock */
 
-#else
-
-#if __i386 || __x86_64
-
-/* WARNING: Make sure to set frequency and scaling functions that will not
- * result in lttv timestamps (sec.nsec) with seconds greater than 2**32-1.
- */
-static __inline__ u64 trace_clock_read64(void)
+static __inline__ uint64_t trace_clock_read64(void)
 {
-       uint32_t low;
-       uint32_t high;
+       struct timespec ts;
        uint64_t retval;
-       __asm__ volatile ("rdtsc\n" : "=a" (low), "=d" (high));
+       union lttng_timespec *lts = (union lttng_timespec *) &ts;
+
+       clock_gettime(ust_clock_source, &ts);
+       /*
+        * Clock source can change when loading the binary (tracectl.c)
+        * so we must check if the clock source has changed before
+        * returning the correct value
+        */
+       if (likely(ust_clock_source == CLOCK_TRACE)) {
+               retval = lts->lttng_ts;
+       } else { /* CLOCK_MONOTONIC */
+               retval = ts.tv_sec;
+               retval *= 1000000000;
+               retval += ts.tv_nsec;
+       }
 
-       retval = high;
-       retval <<= 32;
-       return retval | low;
+       return retval;
 }
 
-#endif /* __i386 || __x86_64 */
-
-#ifdef __PPC__
-
-static __inline__ u64 trace_clock_read64(void)
+#if __i386__ || __x86_64__
+static __inline__ uint64_t trace_clock_frequency(void)
 {
-       unsigned long tb_l;
-       unsigned long tb_h;
-       unsigned long tb_h2;
-       u64 tb;
-
-       __asm__ (
-               "1:\n\t"
-               "mftbu %[rhigh]\n\t"
-               "mftb %[rlow]\n\t"
-               "mftbu %[rhigh2]\n\t"
-               "cmpw %[rhigh],%[rhigh2]\n\t"
-               "bne 1b\n\t"
-       : [rhigh] "=r" (tb_h), [rhigh2] "=r" (tb_h2), [rlow] "=r" (tb_l));
-       
-       tb = tb_h;
-       tb <<= 32;
-       tb |= tb_l;
-
-       return tb;
+       struct timespec ts;
+       union lttng_timespec *lts = (union lttng_timespec *) &ts;
+
+       if (likely(ust_clock_source == CLOCK_TRACE)) {
+               clock_gettime(CLOCK_TRACE_FREQ, &ts);
+               return lts->lttng_ts;
+       }
+       return 1000000000LL;
 }
-
-#endif /* __PPC__ */
-
-#endif /* ! UST_TRACE_CLOCK_GENERIC */
-
-static __inline__ u64 trace_clock_frequency(void)
+#else /* #if __i386__ || __x86_64__ */
+static __inline__ uint64_t trace_clock_frequency(void)
 {
-       return 1000000LL;
+       return 1000000000LL;
 }
+#endif /* #else #if __i386__ || __x86_64__ */
 
-static __inline__ u32 trace_clock_freq_scale(void)
+static __inline__ uint32_t trace_clock_freq_scale(void)
 {
        return 1;
 }
 
-#endif /* UST_CLOCK_H */
+#endif /* _UST_CLOCK_H */