blob: a9cc0e34efd65bb2b526cc13e7c986a1739fa8e4 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
|
From 8959451a8ec5dc83dcb2dba6701abe8bf419e12c Mon Sep 17 00:00:00 2001
Message-Id: <8959451a8ec5dc83dcb2dba6701abe8bf419e12c.1358783585.git.Jim.Somerville@windriver.com>
From: Jim Somerville <Jim.Somerville@windriver.com>
Date: Mon, 21 Jan 2013 10:50:18 -0500
Subject: [PATCH 1/1] cyclictest: finish removal of 1 second first loops
Observation:
Huge latencies reported close to 1 second when certain options
are used in cyclictest.
Problem:
[ commit da4956cbcaf7945554f30e4d3a9be09b1431b19a
use interval on first loop instead of 1 second ]
removed the 1 second first timing loop out of the main path
in cyclictest but left it in two other paths, namely the ones
triggered by these two options:
-r --relative use relative timer instead of absolute
-s --system use sys_nanosleep and sys_setitimer
This causes huge latencies of close to 1 second to be reported
by cyclictest with certain uses of those two options.
Fix:
Extend the original commit to remove the 1 second hardcoded
timer values from the RELTIME and ITIMER options. Use the
the actual interval instead.
Upstream-Status: Accepted
[ https://git.kernel.org/cgit/linux/kernel/git/clrkwllms/rt-tests.git/commit/?h=work&id=1b92da30837e9552aba209cbdf938877f0fd3bbf ]
Signed-off-by: Jim Somerville <Jim.Somerville@windriver.com>
---
src/cyclictest/cyclictest.c | 6 ++----
1 files changed, 2 insertions(+), 4 deletions(-)
diff --git a/src/cyclictest/cyclictest.c b/src/cyclictest/cyclictest.c
index 11b6cea..8487409 100644
--- a/src/cyclictest/cyclictest.c
+++ b/src/cyclictest/cyclictest.c
@@ -741,17 +741,15 @@ void *timerthread(void *param)
if (par->timermode == TIMER_ABSTIME)
tspec.it_value = next;
else {
- tspec.it_value.tv_nsec = 0;
- tspec.it_value.tv_sec = 1;
+ tspec.it_value = interval;
}
timer_settime(timer, par->timermode, &tspec, NULL);
}
if (par->mode == MODE_SYS_ITIMER) {
- itimer.it_value.tv_sec = 1;
- itimer.it_value.tv_usec = 0;
itimer.it_interval.tv_sec = interval.tv_sec;
itimer.it_interval.tv_usec = interval.tv_nsec / 1000;
+ itimer.it_value = itimer.it_interval;
setitimer (ITIMER_REAL, &itimer, NULL);
}
--
1.7.4.1
|
