From: Willy Tarreau <w@1wt.eu>
Date: Thu, 5 Mar 2009 13:54:50 +0000 (+0100)
Subject: [MINOR] add curr_sec_ms and curr_sec_ms_scaled for current second.
X-Git-Tag: v1.3.16-rc1~30
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=755905857ac26c28d9886ab94c410b6fec4de192;p=thirdparty%2Fhaproxy.git

[MINOR] add curr_sec_ms and curr_sec_ms_scaled for current second.

Several algorithms will need to know the millisecond value within
the current second. Instead of doing a divide every time it is needed,
it's better to compute it when it changes, which is when now and now_ms
are recomputed.

curr_sec_ms_scaled is the same multiplied by 2^32/1000, which will be
useful to compute some ratios based on the position within last second.
---

diff --git a/include/common/time.h b/include/common/time.h
index 07d3070eb6..abc1ccfa3f 100644
--- a/include/common/time.h
+++ b/include/common/time.h
@@ -54,6 +54,8 @@
 #define MINTIME(old, new)	(((new)<0)?(old):(((old)<0||(new)<(old))?(new):(old)))
 #define SETNOW(a)		(*a=now)
 
+extern unsigned int   curr_sec_ms;      /* millisecond of current second (0..999) */
+extern unsigned int   curr_sec_ms_scaled;  /* millisecond of current second (0..2^32-1) */
 extern unsigned int   now_ms;           /* internal date in milliseconds (may wrap) */
 extern struct timeval now;              /* internal date is a monotonic function of real clock */
 extern struct timeval date;             /* the real current date */
diff --git a/src/time.c b/src/time.c
index 5318dcdf26..1b0f72c45b 100644
--- a/src/time.c
+++ b/src/time.c
@@ -1,7 +1,7 @@
 /*
  * Time calculation functions.
  *
- * Copyright 2000-2008 Willy Tarreau <w@1wt.eu>
+ * Copyright 2000-2009 Willy Tarreau <w@1wt.eu>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
@@ -16,6 +16,8 @@
 #include <common/standard.h>
 #include <common/time.h>
 
+unsigned int   curr_sec_ms;      /* millisecond of current second (0..999) */
+unsigned int   curr_sec_ms_scaled;  /* millisecond of current second (0..2^32-1) */
 unsigned int   now_ms;          /* internal date in milliseconds (may wrap) */
 struct timeval now;             /* internal date is a monotonic function of real clock */
 struct timeval date;            /* the real current date */
@@ -162,7 +164,7 @@ REGPRM2 void tv_update_date(int max_wait, int interrupted)
 	gettimeofday(&date, NULL);
 	if (unlikely(max_wait < 0)) {
 		tv_zero(&tv_offset);
-		now = date;
+		adjusted = date;
 		goto to_ms;
 	}
 	__tv_add(&adjusted, &date, &tv_offset);
@@ -175,26 +177,26 @@ REGPRM2 void tv_update_date(int max_wait, int interrupted)
 	 * MAX_DELAY_MS to cover additional time.
 	 */
 	_tv_ms_add(&deadline, &now, max_wait + MAX_DELAY_MS);
-	if (unlikely(__tv_isge(&adjusted, &deadline))) {
-		goto fixup; /* jump in the future */
-	}
-	now = adjusted;
-	goto to_ms;
+	if (likely(__tv_islt(&adjusted, &deadline)))
+		goto to_ms; /* OK time is within expected range */
  fixup:
 	/* Large jump. If the poll was interrupted, we consider that the date
 	 * has not changed (immediate wake-up), otherwise we add the poll
 	 * time-out to the previous date. The new offset is recomputed.
 	 */
-	if (!interrupted)
-		_tv_ms_add(&now, &now, max_wait);
-	tv_offset.tv_sec  = now.tv_sec  - date.tv_sec;
-	tv_offset.tv_usec = now.tv_usec - date.tv_usec;
+	_tv_ms_add(&adjusted, &now, interrupted ? 0 : max_wait);
+
+	tv_offset.tv_sec  = adjusted.tv_sec  - date.tv_sec;
+	tv_offset.tv_usec = adjusted.tv_usec - date.tv_usec;
 	if (tv_offset.tv_usec < 0) {
 		tv_offset.tv_usec += 1000000;
 		tv_offset.tv_sec--;
 	}
  to_ms:
-	now_ms = now.tv_sec * 1000 + now.tv_usec / 1000;
+	now = adjusted;
+	curr_sec_ms = now.tv_usec / 1000;            /* ms of current second */
+	curr_sec_ms_scaled = curr_sec_ms * 4294971;  /* ms * 2^32 / 1000 */
+	now_ms = now.tv_sec * 1000 + curr_sec_ms;
 	return;
 }