diff mbox

[api-next,V6,1/5] test: correct worker count calculation

Message ID 1459375796-23992-2-git-send-email-gary.robertson@linaro.org
State Accepted
Commit e43e013fccee3b22a2809d611eb2294f469ce82d
Headers show

Commit Message

gary.robertson@linaro.org March 30, 2016, 10:09 p.m. UTC
During the process of addressing Linaro BUG 2027 which relates to
inaccurate reporting of available CPUs by ODP linux-generic when
running atop a kernel compiled with NO_HZ_FULL support,
a number of instances were encountered in the validation and
performance test software where incorrect methods were used to
determine the proper (or maximum) number of worker threads to create.

    See Linaro BUG 2027 for details.
    	https://bugs.linaro.org/show_bug.cgi?id=2027

The use of odp_cpu_count() for this purpose is incorrect and
deprecated... odp_cpumask_default_worker() should always be used
to determine the set and number of CPUs available for creating
worker threads.

The use of odp_cpu_count() for this purpose in conjunction with the
correct means of determining available CPUs resulted in some tests
hanging in calls to odp_barrier_wait() as the barriers were initialized
to expect threads on ALL CPUs rather than on worker CPUs alone...
and there were too few worker threads created to satisfy the barriers.

The changes below correct all instances I could find of this deprecated
technique and allowed all tests to complete successfully with the
BUG 2027 patch applied. (BTW they also run correctly without that patch
after the application of the modifications included here.)

Signed-off-by: Gary S. Robertson <gary.robertson@linaro.org>
---
 test/validation/shmem/shmem.c |  3 ++-
 test/validation/timer/timer.c | 18 ++++++++++--------
 2 files changed, 12 insertions(+), 9 deletions(-)
diff mbox

Patch

diff --git a/test/validation/shmem/shmem.c b/test/validation/shmem/shmem.c
index ba4973d..0bf38d2 100644
--- a/test/validation/shmem/shmem.c
+++ b/test/validation/shmem/shmem.c
@@ -52,6 +52,7 @@  void shmem_test_odp_shm_sunnyday(void)
 	pthrd_arg thrdarg;
 	odp_shm_t shm;
 	test_shared_data_t *test_shared_data;
+	odp_cpumask_t unused;
 
 	shm = odp_shm_reserve(TESTNAME,
 			      sizeof(test_shared_data_t), ALIGE_SIZE, 0);
@@ -70,7 +71,7 @@  void shmem_test_odp_shm_sunnyday(void)
 	test_shared_data->foo = TEST_SHARE_FOO;
 	test_shared_data->bar = TEST_SHARE_BAR;
 
-	thrdarg.numthrds = odp_cpu_count();
+	thrdarg.numthrds = odp_cpumask_default_worker(&unused, 0);
 
 	if (thrdarg.numthrds > MAX_WORKERS)
 		thrdarg.numthrds = MAX_WORKERS;
diff --git a/test/validation/timer/timer.c b/test/validation/timer/timer.c
index 7b76dbf..aad11aa 100644
--- a/test/validation/timer/timer.c
+++ b/test/validation/timer/timer.c
@@ -14,7 +14,8 @@ 
 #endif
 
 #include <time.h>
-#include <odp_api.h>
+#include <odp.h>
+#include <odp/helper/linux.h>
 #include "odp_cunit_common.h"
 #include "test_debug.h"
 #include "timer.h"
@@ -41,12 +42,6 @@  static odp_atomic_u32_t ndelivtoolate;
  * caches may make this number lower than the capacity of the pool  */
 static odp_atomic_u32_t timers_allocated;
 
-/** @private min() function */
-static int min(int a, int b)
-{
-	return a < b ? a : b;
-}
-
 /* @private Timer helper structure */
 struct test_timer {
 	odp_timer_t tim; /* Timer handle */
@@ -457,10 +452,17 @@  void timer_test_odp_timer_all(void)
 	int rc;
 	odp_pool_param_t params;
 	odp_timer_pool_param_t tparam;
+	odp_cpumask_t unused;
+
 	/* Reserve at least one core for running other processes so the timer
 	 * test hopefully can run undisturbed and thus get better timing
 	 * results. */
-	int num_workers = min(odp_cpu_count() - 1, MAX_WORKERS);
+	int num_workers = odp_cpumask_default_worker(&unused, 0);
+
+	/* force to max CPU count */
+	if (num_workers > MAX_WORKERS)
+		num_workers = MAX_WORKERS;
+
 	/* On a single-CPU machine run at least one thread */
 	if (num_workers < 1)
 		num_workers = 1;