samples: coremark: Set cooperative priority for main thread

Drivers need to be run from non blocking thread.
We need preemptive priority during init.
Later we prefer cooperative priority
to ensure no interference with benchmark.

JIRA: NCSDK-30369

Signed-off-by: Jan Zyczkowski <[email protected]>

Author: zycz

samples/benchmarks/coremark/prj.conf

@@ -20,8 +20,6 @@ CONFIG_CBPRINTF_FP_SUPPORT=y
 
 CONFIG_GPIO=y
 
-CONFIG_MAIN_THREAD_PRIORITY=-1
-
 # Configuration variant:
 # Memory allocation using the stack memory
 # Single-threaded benchmark execution

samples/benchmarks/coremark/prj_flash_and_run.conf

@@ -20,8 +20,6 @@ CONFIG_CBPRINTF_FP_SUPPORT=y
 
 CONFIG_GPIO=y
 
-CONFIG_MAIN_THREAD_PRIORITY=-1
-
 # Configuration variant:
 # Memory allocation using the stack memory
 # Single-threaded benchmark execution

samples/benchmarks/coremark/prj_heap_memory.conf

@@ -20,8 +20,6 @@ CONFIG_CBPRINTF_FP_SUPPORT=y
 
 CONFIG_GPIO=y
 
-CONFIG_MAIN_THREAD_PRIORITY=-1
-
 # Configuration variant:
 # Memory allocation using the heap memory
 # Single-threaded benchmark execution

samples/benchmarks/coremark/prj_multiple_threads.conf

@@ -20,8 +20,6 @@ CONFIG_CBPRINTF_FP_SUPPORT=y
 
 CONFIG_GPIO=y
 
-CONFIG_MAIN_THREAD_PRIORITY=-1
-
 # Configuration variant:
 # Memory allocation using the stack memory
 # Multi-threaded benchmark execution

samples/benchmarks/coremark/prj_static_memory.conf

@@ -20,8 +20,6 @@ CONFIG_CBPRINTF_FP_SUPPORT=y
 
 CONFIG_GPIO=y
 
-CONFIG_MAIN_THREAD_PRIORITY=-1
-
 # Configuration variant:
 # Memory allocation using the static memory
 # Single-threaded benchmark execution

samples/benchmarks/coremark/src/main.c

@@ -15,6 +15,8 @@
 
 LOG_MODULE_REGISTER(app, LOG_LEVEL_INF);
 
+#define COOP_PRIO -1
+
 #ifndef CONFIG_APP_MODE_FLASH_AND_RUN
 /*
  * Get button configuration from the devicetree. This is mandatory.
@@ -170,8 +172,20 @@ static int button_init(void)
 	return ret;
 }
 
+static void main_thread_priority_cooperative_set(void)
+{
+	BUILD_ASSERT(CONFIG_MAIN_THREAD_PRIORITY >= 0);
+	k_thread_priority_set(k_current_get(), COOP_PRIO);
+}
+
 int main(void)
 {
+	/* Drivers need to be run from a non-blocking thread.
+	 * We need preemptive priority during init.
+	 * Later we prefer cooperative priority to ensure no interference with the benchmark.
+	 */
+	main_thread_priority_cooperative_set();
+
 	LOG_INF("CoreMark sample for %s", CONFIG_BOARD_TARGET);
 
 	if (IS_ENABLED(CONFIG_APP_MODE_FLASH_AND_RUN)) {