[prev in list] [next in list] [prev in thread] [next in thread]
List: ltp-list
Subject: [LTP] [PATCH] prio-wake: enable using more than 95 threads
From: Darren Hart <dvhltc () us ! ibm ! com>
Date: 2010-01-28 19:38:48
Message-ID: 4B61E7C8.9090602 () us ! ibm ! com
[Download RAW message or body]
prio-wake: enable using more than 95 threads
prio-wake will currently spew pthread errors on systems with more
than 95 CPUS, or if an -n value > 95 is specified on the command line.
To avoid this, spread threads out equally over the priorities by
calculated the number of threads per priority.
Tested with all pathological numbers (i.e. mod=0 mod=1, etc) of threads.
Ran 10000 times in parallel. Confirmed failure continues to exist without
requeue PI (as it should) and success is seen with requeue PI
(as it should be).
Signed-off-by: Darren Hart <dvhltc@us.ibm.com>
Acked-By: Dinakar Guniguntala <dino@in.ibm.com>
Acked-by: Vernon Mauery <vernux@us.ibm.com>
Acked-by: Gowrishankar <gowrishankar.m@in.ibm.com>
---
func/prio-wake/prio-wake.c | 24 +++++++++++++++++++-----
1 file changed, 19 insertions(+), 5 deletions(-)
Index: realtime/func/prio-wake/prio-wake.c
===================================================================
--- realtime.orig/func/prio-wake/prio-wake.c
+++ realtime/func/prio-wake/prio-wake.c
@@ -54,6 +54,8 @@
#include <errno.h>
#include <sys/syscall.h>
#include <librttest.h>
+#include <libstats.h>
+
volatile int running_threads = 0;
static int rt_threads = 0;
static int locked_broadcast = 1;
@@ -164,8 +166,10 @@ void *worker_thread(void* arg)
int main(int argc, char* argv[])
{
- int pri_boost;
+ int threads_per_prio;
int numcpus;
+ int numprios;
+ int prio;
int i;
setup();
@@ -184,19 +188,29 @@ int main(int argc, char* argv[])
printf("Calling pthread_cond_broadcast() with mutex: %s\n\n",
locked_broadcast ? "LOCKED" : "UNLOCKED");
- pri_boost = 3;
-
beginrun = rt_gettime();
init_pi_mutex(&mutex);
+ /* calculate the number of threads per priority */
+ /* we get num numprios -1 for the workers, leaving one for the master */
+ numprios = sched_get_priority_max(SCHED_FIFO) -
+ sched_get_priority_min(SCHED_FIFO);
+
+ threads_per_prio = rt_threads / numprios;
+ if (rt_threads % numprios)
+ threads_per_prio++;
+
/* start the worker threads */
+ prio = sched_get_priority_min(SCHED_FIFO);
for (i = rt_threads; i > 0; i--) {
- create_fifo_thread(worker_thread, (void*)(intptr_t)i, \
sched_get_priority_min(SCHED_FIFO) + pri_boost++); + if ((i != rt_threads && (i % \
threads_per_prio) == 0)) + prio++;
+ create_fifo_thread(worker_thread, (void*)(intptr_t)i, prio);
}
/* start the master thread */
- create_fifo_thread(master_thread, (void*)(intptr_t)i, \
sched_get_priority_min(SCHED_FIFO) + pri_boost); + create_fifo_thread(master_thread, \
(void*)(intptr_t)i, ++prio);
/* wait for threads to complete */
join_threads();
--
Darren Hart
IBM Linux Technology Center
Real-Time Linux Team
------------------------------------------------------------------------------
The Planet: dedicated and managed hosting, cloud storage, colocation
Stay online with enterprise data centers and the best network in the business
Choose flexible plans and management services without long-term contracts
Personal 24x7 support from experience hosting pros just a phone call away.
http://p.sf.net/sfu/theplanet-com
_______________________________________________
Ltp-list mailing list
Ltp-list@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/ltp-list
[prev in list] [next in list] [prev in thread] [next in thread]
Configure |
About |
News |
Add a list |
Sponsored by KoreLogic