On 2015-05-26 21:07, anna-maria@xxxxxxxxx wrote:
+ case OPT_SECALIGNED:
+ secaligned = 1;
+ if (optarg != NULL)
+ offset = atoi(optarg) * 1000;
+ else if (optind < argc && atoi(argv[optind]))
The conversion to microseconds is missing as well.
+ offset = atoi(argv[optind]);
+ else
The patch is fixed.
Anna-Maria
cyclictest starts the test threads at a random point in time. For
fully reproducible tests it is required to schedule the threads with a
specified offset from the timer tick. The influence of the tick can be
measured by running the test with offset = 0 and offset =
tickinterval/2.
To achieve this we rely on the fact, that the kernel starts the tick
at CLOCK_MONOTONIC time 0. So it's guaranteed that the tick timer
expires always every second (if the interval between the ticks defined
by CONFIG_HZ is a whole-number divider of a second). Setting the
global start time of the test threads to a full second (plus offset)
and the interval to the interval between the ticks, the threads are
scheduled with the specified offset to the tick.
Add a new option --secaligned which select this mode and modify the
--aligned option code to support this. The --secaligned and --aligned
options are mutually exclusive.
Signed-off-by Anna-Maria Gleixner <anna-maria@xxxxxxxxx>
---
src/cyclictest/cyclictest.c | 39
++++++++++++++++++++++++++++++++++-----
1 file changed, 34 insertions(+), 5 deletions(-)
Index: rt-tests/src/cyclictest/cyclictest.c
===================================================================
--- rt-tests.orig/src/cyclictest/cyclictest.c
+++ rt-tests/src/cyclictest/cyclictest.c
@@ -185,6 +185,7 @@ static int ct_debug;
static int use_fifo = 0;
static pthread_t fifo_threadid;
static int aligned = 0;
+static int secaligned = 0;
static int offset = 0;
static int laptop = 0;
@@ -798,14 +799,27 @@ void *timerthread(void *param)
fatal("timerthread%d: failed to set priority to %d\n", par->cpu,
par->prio);
/* Get current time */
- if(aligned){
+ if (aligned || secaligned) {
pthread_barrier_wait(&globalt_barr);
- if(par->tnum==0)
+ if (par->tnum == 0) {
clock_gettime(par->clock, &globalt);
+ if (secaligned) {
+ /* Ensure that the thread start timestamp is not
+ in the past */
+ if (globalt.tv_nsec > 900000000)
+ globalt.tv_sec += 2;
+ else
+ globalt.tv_sec++;
+ globalt.tv_nsec = 0;
+ }
+ }
pthread_barrier_wait(&align_barr);
now = globalt;
if(offset) {
- now.tv_nsec += offset * par->tnum;
+ if (aligned)
+ now.tv_nsec += offset * par->tnum;
+ else
+ now.tv_nsec += offset;
tsnorm(&now);
}
}
@@ -1056,6 +1070,8 @@ static void display_help(int error)
"-R --resolution check clock resolution, calling
clock_gettime() many\n"
" times. list of clock_gettime()
values will be\n"
" reported with -X\n"
+ " --secaligned [USEC] align thread wakeups to the next
full second,\n"
+ " and apply the optional offset\n"
"-s --system use sys_nanosleep and
sys_setitimer\n"
"-S --smp Standard SMP testing: options -a
-t -n and\n"
" same priority of all threads\n"
@@ -1204,7 +1220,7 @@ enum option_values {
OPT_QUIET, OPT_PRIOSPREAD, OPT_RELATIVE, OPT_RESOLUTION, OPT_SYSTEM,
OPT_SMP, OPT_THREADS, OPT_TRACER, OPT_UNBUFFERED, OPT_NUMA,
OPT_VERBOSE,
OPT_WAKEUP, OPT_WAKEUPRT, OPT_DBGCYCLIC, OPT_POLICY, OPT_HELP,
OPT_NUMOPTS,
- OPT_ALIGNED, OPT_LAPTOP,
+ OPT_ALIGNED, OPT_LAPTOP, OPT_SECALIGNED,
};
/* Process commandline options */
@@ -1251,6 +1267,7 @@ static void process_options (int argc, c
{"priospread", no_argument, NULL, OPT_PRIOSPREAD },
{"relative", no_argument, NULL, OPT_RELATIVE },
{"resolution", no_argument, NULL, OPT_RESOLUTION },
+ {"secaligned", optional_argument, NULL, OPT_SECALIGNED },
{"system", no_argument, NULL, OPT_SYSTEM },
{"smp", no_argument, NULL, OPT_SMP },
{"threads", optional_argument, NULL, OPT_THREADS },
@@ -1391,6 +1408,15 @@ static void process_options (int argc, c
case OPT_RESOLUTION:
check_clock_resolution = 1; break;
case 's':
+ case OPT_SECALIGNED:
+ secaligned = 1;
+ if (optarg != NULL)
+ offset = atoi(optarg) * 1000;
+ else if (optind < argc && atoi(argv[optind]))
+ offset = atoi(argv[optind]) * 1000;
+ else
+ offset = 0;
+ break;
case OPT_SYSTEM:
use_system = MODE_SYS_OFFSET; break;
case 'S':
@@ -1528,7 +1554,10 @@ static void process_options (int argc, c
if (num_threads < 1)
error = 1;
- if (aligned) {
+ if (aligned && secaligned)
+ error = 1;
+
+ if (aligned || secaligned) {
pthread_barrier_init(&globalt_barr, NULL, num_threads);
pthread_barrier_init(&align_barr, NULL, num_threads);
}
--
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