libtest: Add T_get_one_clock_tick_busy()

Update #3199.

cpukit/Makefile.am

@@ -1858,6 +1858,7 @@ librtemstest_a_SOURCES += libtest/testparallel.c
 librtemstest_a_SOURCES += libtest/testwrappers.c
 librtemstest_a_SOURCES += libtest/t-test.c
 librtemstest_a_SOURCES += libtest/t-test-busy.c
+librtemstest_a_SOURCES += libtest/t-test-busy-tick.c
 librtemstest_a_SOURCES += libtest/t-test-checks.c
 librtemstest_a_SOURCES += libtest/t-test-checks-eno.c
 librtemstest_a_SOURCES += libtest/t-test-checks-psx.c

cpukit/include/rtems/test-info.h

@@ -304,12 +304,6 @@ void rtems_test_parallel(
  */
 void rtems_test_busy_cpu_usage(time_t seconds, long nanoseconds);
 
-/**
- * @brief Returns a count value for T_busy() which yields roughly a
- * duration of one clock tick.
- */
-uint_fast32_t rtems_test_get_one_tick_busy_count(void);
-
 /** @} */
 
 #ifdef __cplusplus

cpukit/include/rtems/test.h

@@ -2263,6 +2263,8 @@ void T_case_body_##name(void)
 
 void T_busy(uint_fast32_t);
 
+uint_fast32_t T_get_one_clock_tick_busy(void);
+
 void T_report_hash_sha256(T_event, const char *);
 
 void T_check_heap(T_event, const char *);

cpukit/libtest/t-test-busy-tick.c

@@ -0,0 +1,121 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+
+/**
+ * @file
+ *
+ * @ingroup RTEMSTestFrameworkImpl
+ *
+ * @brief Implementation of T_get_one_clock_tick_busy().
+ */
+
+/*
+ * Copyright (C) 2014, 2020 embedded brains GmbH (http://www.embedded-brains.de)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <rtems/test.h>
+
+#include <rtems.h>
+
+static uint_fast32_t
+T_estimate_busy_loop_maximum(void)
+{
+	uint_fast32_t initial;
+	uint_fast32_t units;
+
+	initial = rtems_clock_get_ticks_since_boot();
+	units = 0;
+
+	while (initial == rtems_clock_get_ticks_since_boot()) {
+		++units;
+	}
+
+	return units;
+}
+
+static uint_fast32_t
+T_wait_for_tick_change(void)
+{
+	uint_fast32_t initial;
+	uint_fast32_t now;
+
+	initial = rtems_clock_get_ticks_since_boot();
+
+	do {
+		now = rtems_clock_get_ticks_since_boot();
+	} while (now == initial);
+
+	return now;
+}
+
+uint_fast32_t
+T_get_one_clock_tick_busy(void)
+{
+	uint_fast32_t last;
+	uint_fast32_t now;
+	uint_fast32_t a;
+	uint_fast32_t b;
+	uint_fast32_t m;
+
+	/* Choose a lower bound */
+	a = 1;
+
+	/* Estimate an upper bound */
+
+	T_wait_for_tick_change();
+	b = 2 * T_estimate_busy_loop_maximum();
+
+	while (true) {
+		last = T_wait_for_tick_change();
+		T_busy(b);
+		now = rtems_clock_get_ticks_since_boot();
+
+		if (now != last) {
+			break;
+		}
+
+		b *= 2;
+		last = now;
+	}
+
+	/* Find a good value */
+	do {
+		m = (a + b) / 2;
+
+		last = T_wait_for_tick_change();
+		T_busy(m);
+		now = rtems_clock_get_ticks_since_boot();
+
+		if (now != last) {
+			b = m;
+		} else {
+			a = m;
+		}
+	} while (b - a > 1);
+
+	return m;
+}

cpukit/libtest/testbusy.c

@@ -18,81 +18,8 @@
 #endif
 
 #include <rtems/test-info.h>
-#include <rtems.h>
-#include <rtems/test.h>
 #include <rtems/score/threadimpl.h>
 
-static uint_fast32_t estimate_busy_loop_maximum( void )
-{
-  uint_fast32_t units = 0;
-  uint_fast32_t initial = rtems_clock_get_ticks_since_boot();
-
-  while ( initial == rtems_clock_get_ticks_since_boot() ) {
-    ++units;
-  }
-
-  return units;
-}
-
-static uint_fast32_t wait_for_tick_change( void )
-{
-  uint_fast32_t initial = rtems_clock_get_ticks_since_boot();
-  uint_fast32_t now;
-
-  do {
-    now = rtems_clock_get_ticks_since_boot();
-  } while ( now == initial );
-
-  return now;
-}
-
-uint_fast32_t rtems_test_get_one_tick_busy_count( void )
-{
-  uint_fast32_t last;
-  uint_fast32_t now;
-  uint_fast32_t a;
-  uint_fast32_t b;
-  uint_fast32_t m;
-
-  /* Choose a lower bound */
-  a = 1;
-
-  /* Estimate an upper bound */
-
-  wait_for_tick_change();
-  b = 2 * estimate_busy_loop_maximum();
-
-  while ( true ) {
-    last = wait_for_tick_change();
-    T_busy( b );
-    now = rtems_clock_get_ticks_since_boot();
-
-    if ( now != last ) {
-      break;
-    }
-
-    b *= 2;
-    last = now;
-  }
-
-  /* Find a good value */
-  do {
-    m = ( a + b ) / 2;
-
-    last = wait_for_tick_change();
-    T_busy( m );
-    now = rtems_clock_get_ticks_since_boot();
-
-    if ( now != last ) {
-      b = m;
-    } else {
-      a = m;
-    }
-  } while ( b - a > 1 );
-
-  return m;
-}
-
 void rtems_test_busy_cpu_usage( time_t seconds, long nanoseconds )
 {
   Thread_Control    *executing;

testsuites/sptests/spintrcritical_support/intrcritical.c

@@ -71,7 +71,7 @@ void interrupt_critical_section_test_support_initialize(
     rtems_test_assert( sc == RTEMS_SUCCESSFUL );
   }
 
-  m = rtems_test_get_one_tick_busy_count();
+  m = T_get_one_clock_tick_busy();
 
   interrupt_critical.minimum = 0;
   interrupt_critical.maximum = m;