[ovs-dev] [PATCH v5 03/10] util: Add high resolution sleep support.

[Bhanuprakash Bodireddy]

This commit introduces xnanosleep() for the threads needing high
resolution sleep timeouts.

Signed-off-by: Bhanuprakash Bodireddy <bhanuprakash.bodireddy at intel.com>
---
 lib/timeval.c |  2 +-
 lib/timeval.h |  1 +
 lib/util.c    | 19 +++++++++++++++++++
 lib/util.h    |  1 +
 4 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/lib/timeval.c b/lib/timeval.c
index dd63f03..8190b41 100644
--- a/lib/timeval.c
+++ b/lib/timeval.c
@@ -474,7 +474,7 @@ xclock_gettime(clock_t id, struct timespec *ts)
     }
 }
 
-static void
+void
 msec_to_timespec(long long int ms, struct timespec *ts)
 {
     ts->tv_sec = ms / 1000;
diff --git a/lib/timeval.h b/lib/timeval.h
index 7957dad..110745c 100644
--- a/lib/timeval.h
+++ b/lib/timeval.h
@@ -69,6 +69,7 @@ size_t strftime_msec(char *s, size_t max, const char *format,
                      const struct tm_msec *);
 void xgettimeofday(struct timeval *);
 void xclock_gettime(clock_t, struct timespec *);
+void msec_to_timespec(long long int , struct timespec *);
 
 int get_cpu_usage(void);
 
diff --git a/lib/util.c b/lib/util.c
index 36e3731..4ad7eea 100644
--- a/lib/util.c
+++ b/lib/util.c
@@ -2197,6 +2197,25 @@ xsleep(unsigned int seconds)
     ovsrcu_quiesce_end();
 }
 
+/* High resolution sleep. */
+void
+xnanosleep(uint64_t ms)
+{
+    ovsrcu_quiesce_start();
+#ifdef __linux__
+    int retval;
+    struct timespec ts_sleep;
+    msec_to_timespec(ms, &ts_sleep);
+
+    int error = 0;
+    do {
+        retval = nanosleep(&ts_sleep, NULL);
+        error = retval < 0 ? errno : 0;
+    } while (error == EINTR);
+#endif
+    ovsrcu_quiesce_end();
+}
+
 /* Determine whether standard output is a tty or not. This is useful to decide
  * whether to use color output or not when --color option for utilities is set
  * to `auto`.
diff --git a/lib/util.h b/lib/util.h
index 764e0a0..0449fa1 100644
--- a/lib/util.h
+++ b/lib/util.h
@@ -489,6 +489,7 @@ ovs_u128_and(const ovs_u128 a, const ovs_u128 b)
 }
 
 void xsleep(unsigned int seconds);
+void xnanosleep(uint64_t ms);
 
 bool is_stdout_a_tty(void);
 
-- 
2.4.11