MINOR: clock: replace the timeval start_time with start_time_ns

Now that "now" is no more a timeval, there's no point keeping a copy
of it as a timeval, let's also switch start_time to nanoseconds, it
simplifies operations.

include/haproxy/clock.h

@@ -26,7 +26,7 @@
 #include <haproxy/api.h>
 
 extern struct timeval              start_date;    /* the process's start date in wall-clock time */
-extern struct timeval              start_time;    /* the process's start date in internal monotonic time */
+extern ullong                      start_time_ns; /* the process's start date in internal monotonic time (ns) */
 extern volatile ullong             global_now_ns; /* common monotonic date between all threads, in ns (wraps every 585 yr) */
 
 extern THREAD_LOCAL ullong         now_ns;        /* internal monotonic date derived from real clock, in ns (wraps every 585 yr) */

src/activity.c

@@ -1087,7 +1087,7 @@ static int cli_io_handler_show_activity(struct appctx *appctx)
 	} while (0)
 
 	/* retrieve uptime */
-	up = now_ns - tv_to_ns(&start_time);
+	up = now_ns - start_time_ns;
 	up_sec = ns_to_sec(up);
 	up_usec = (up / 1000U) % 1000000U;
 

src/clock.c

@@ -27,7 +27,7 @@
 #include <haproxy/tools.h>
 
 struct timeval                   start_date;      /* the process's start date in wall-clock time */
-struct timeval                   start_time;      /* the process's start date in internal monotonic time */
+ullong                           start_time_ns;   /* the process's start date in internal monotonic time (ns) */
 volatile ullong                  global_now_ns;   /* common monotonic date between all threads, in ns (wraps every 585 yr) */
 volatile uint                    global_now_ms;   /* common monotonic date in milliseconds (may wrap) */
 

src/haproxy.c

@@ -1509,7 +1509,7 @@ static void init_early(int argc, char **argv)
 	tzset();
 	clock_init_process_date();
 	start_date = date;
-	start_time = NS_TO_TV(now_ns);
+	start_time_ns = now_ns;
 	pid = getpid();
 
 	/* Set local host name and adjust some environment variables.

src/hlua_fcn.c

@@ -305,8 +305,7 @@ int hlua_now(lua_State *L)
 	 */
 	struct timeval tv;
 
-	tv = NS_TO_TV(now_ns);
-	tv_remain(&start_time, &tv, &tv);  // tv = now_ns - start_time
+	tv = NS_TO_TV(now_ns - start_time_ns);
 	tv_add(&tv, &tv, &start_date);
 
 	lua_newtable(L);

src/stats.c

@@ -3555,7 +3555,7 @@ static void stats_dump_html_info(struct stconn *sc, struct uri_auth *uri)
 {
 	struct appctx *appctx = __sc_appctx(sc);
 	struct show_stat_ctx *ctx = appctx->svcctx;
-	unsigned int up = (ns_to_sec(now_ns) - start_time.tv_sec);
+	unsigned int up = ns_to_sec(now_ns - start_time_ns);
 	char scope_txt[STAT_SCOPE_TXT_MAXLEN + sizeof STAT_SCOPE_PATTERN];
 	const char *scope_ptr = stats_scope_ptr(appctx, sc);
 	unsigned long long bps;
@@ -4628,7 +4628,7 @@ int stats_fill_info(struct field *info, int len, uint flags)
 	}
 	glob_out_b32 *= 32; // values are 32-byte units
 
-	up = now_ns - tv_to_ns(&start_time);
+	up = now_ns - start_time_ns;
 	up_sec = ns_to_sec(up);
 	up_usec = (up / 1000U) % 1000000U;