From: mquinson <mquinson@48e7efb5-ca39-0410-a469-dd3cf9ba447f>
Date: Mon, 22 Mar 2010 16:29:22 +0000 (+0000)
Subject: Use nanosecond timers if found
X-Git-Tag: SVN~441
X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/commitdiff_plain/04cb78f32377e433ce4d2d152e03a68c32c42fd0

Use nanosecond timers if found

git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/simgrid/simgrid/trunk@7298 48e7efb5-ca39-0410-a469-dd3cf9ba447f
---

diff --git a/configure.ac b/configure.ac
index 4e693038e2..2f9d91fe70 100644
--- a/configure.ac
+++ b/configure.ac
@@ -32,6 +32,11 @@ dnl We do build a proper DLL when using win32
 AC_LIBTOOL_WIN32_DLL
 AC_PROG_LIBTOOL
 
+SIMGRID_DEP=""
+SMPI_DEP=""
+GRAS_DEP=""
+
+
 ###############
 ## SVN version check
 ##
@@ -71,7 +76,7 @@ AC_CHECK_FUNCS([gettimeofday usleep \
                 sysconf\
                 readv\
 		popen\
-		signal])
+		signal])	   
   
 dnl GNU systems before POSIX2008 need the _GNU_SOURCE definition to find getline (and simgrid does pass this)             
 AC_MSG_CHECKING(a usable getline)
@@ -91,7 +96,14 @@ AC_LINK_IFELSE([
     AC_DEFINE(SIMGRID_NEED_GETLINE, 1, enable the getline replacement)
     AC_MSG_RESULT(not found (activating internal implementation))
   ])
-              
+
+dnl AC_MSG_CHECKING(POSIX timer functions)
+AC_CHECK_LIB(rt, [clock_gettime], [
+    AC_DEFINE(HAVE_POSIX_GETTIME, 1, POSIX timer functions were found)
+    SIMGRID_DEP="$SIMGRID_DEP -lrt"
+    GRAS_DEP="$GRAS_DEP -lrt"
+  ])
+
 # check for a working snprintf (or use xbt/snprintf.c, which comes from http://www.ijs.si/software/snprintf/)
 AC_FUNC_SNPRINTF
 # check for asprintf function familly (or request the replacements from xbt/snprintf.c)
@@ -273,19 +285,15 @@ fi
 
 SG_CONFIGURE_PART(Checking extra libraries dependencies...)
 
-SIMGRID_DEP=""
-SMPI_DEP=""
-GRAS_DEP=""
-
 if test xpthread=xyes ; then 
   # if the pthreads are usable
   if test "x$with_context" = "xpthread" ; then
     # if we use them to implement the xbt_context
-    SIMGRID_DEP="-lpthread"
+    SIMGRID_DEP="$SIMGRID_DEP -lpthread"
   fi
   # we need them in any case for the gras lib (which is multithreaded), but on windows (of course)
   if test "x$with_context" != "xwindows" ; then
-    GRAS_DEP="-lpthread"
+    GRAS_DEP="$GRAS_DEP -lpthread"
   fi
 fi
 AC_SEARCH_LIBS([connect],[socket],[],[],[]) # need -lsocket on solaris
diff --git a/src/xbt/xbt_os_time.c b/src/xbt/xbt_os_time.c
index ebd1f8bff7..3b0a26b2b7 100644
--- a/src/xbt/xbt_os_time.c
+++ b/src/xbt/xbt_os_time.c
@@ -85,35 +85,37 @@ void xbt_os_sleep(double sec)
 
 
 struct s_xbt_os_timer {
-#ifdef HAVE_GETTIMEOFDAY
+#ifdef HAVE_POSIX_GETTIME
+  struct timespec start, stop;
+#elif defined(HAVE_GETTIMEOFDAY)
   struct timeval start, stop;
 #else
   unsigned long int start, stop;
 #endif
 };
 
-xbt_os_timer_t xbt_os_timer_new(void)
-{
+xbt_os_timer_t xbt_os_timer_new(void) {
   return xbt_new0(struct s_xbt_os_timer, 1);
 }
 
-void xbt_os_timer_free(xbt_os_timer_t timer)
-{
+void xbt_os_timer_free(xbt_os_timer_t timer) {
   free(timer);
 }
 
-void xbt_os_timer_start(xbt_os_timer_t timer)
-{
-#ifdef HAVE_GETTIMEOFDAY
+void xbt_os_timer_start(xbt_os_timer_t timer) {
+#ifdef HAVE_POSIX_GETTIME
+  clock_gettime(CLOCK_PROCESS_CPUTIME_ID,&(timer->start));
+#elif defined(HAVE_GETTIMEOFDAY)
   gettimeofday(&(timer->start), NULL);
 #else
   timer->start = (unsigned long int) (time(NULL));
 #endif
 }
 
-void xbt_os_timer_stop(xbt_os_timer_t timer)
-{
-#ifdef HAVE_GETTIMEOFDAY
+void xbt_os_timer_stop(xbt_os_timer_t timer) {
+#ifdef HAVE_POSIX_GETTIME
+  clock_gettime(CLOCK_PROCESS_CPUTIME_ID,&(timer->stop));
+#elif defined(HAVE_GETTIMEOFDAY)
   gettimeofday(&(timer->stop), NULL);
 #else
   timer->stop = (unsigned long int) (time(NULL));
@@ -122,7 +124,11 @@ void xbt_os_timer_stop(xbt_os_timer_t timer)
 
 double xbt_os_timer_elapsed(xbt_os_timer_t timer)
 {
-#ifdef HAVE_GETTIMEOFDAY
+#ifdef HAVE_POSIX_GETTIME
+  return ((double) timer->stop.tv_sec) - ((double) timer->start.tv_sec) +
+      ((((double) timer->stop.tv_nsec) -
+        ((double) timer->start.tv_nsec)) / 1e-9);
+#elif defined(HAVE_GETTIMEOFDAY)
   return ((double) timer->stop.tv_sec) - ((double) timer->start.tv_sec) +
     ((((double) timer->stop.tv_usec) -
       ((double) timer->start.tv_usec)) / 1000000.0);