[PATCH 1/2] lib/core/fiber: Rename stack_direction to stack_growsdown

[Cyrill Gorcunov <gorcunov@gmail.com>]

Since growsdown (or growsup) is more clear and common name.
---
 src/lib/core/fiber.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/src/lib/core/fiber.c b/src/lib/core/fiber.c
index c55b3ab39..922a0bfe8 100644
--- a/src/lib/core/fiber.c
+++ b/src/lib/core/fiber.c
@@ -105,7 +105,7 @@ __thread struct cord *cord_ptr = NULL;
 pthread_t main_thread_id;
 
 static size_t page_size;
-static int stack_direction;
+static bool stack_growsdown;
 
 enum {
 	/* The minimum allowable fiber stack size in bytes */
@@ -808,7 +808,7 @@ fiber_stack_recycle(struct fiber *fiber)
 	 * it anyway.
 	 */
 	void *start, *end;
-	if (stack_direction < 0) {
+	if (stack_growsdown) {
 		start = fiber->stack;
 		end = page_align_down(fiber->stack_watermark);
 	} else {
@@ -842,7 +842,7 @@ fiber_stack_watermark_create(struct fiber *fiber)
 	 * we put the first mark at a random position.
 	 */
 	size_t offset = rand() % POISON_OFF * sizeof(poison_pool[0]);
-	if (stack_direction < 0) {
+	if (stack_growsdown) {
 		fiber->stack_watermark  = fiber->stack + fiber->stack_size;
 		fiber->stack_watermark -= FIBER_STACK_SIZE_WATERMARK;
 		fiber->stack_watermark += offset;
@@ -881,7 +881,7 @@ fiber_stack_create(struct fiber *fiber, size_t stack_size)
 	}
 	void *guard;
 	/* Adjust begin and size for stack memory chunk. */
-	if (stack_direction < 0) {
+	if (stack_growsdown) {
 		/*
 		 * A stack grows down. First page after begin of a
 		 * stack memory chunk should be protected and memory
@@ -922,7 +922,7 @@ fiber_stack_destroy(struct fiber *fiber, struct slab_cache *slabc)
 		ASAN_UNPOISON_MEMORY_REGION(fiber->stack, fiber->stack_size);
 #endif
 		void *guard;
-		if (stack_direction < 0)
+		if (stack_growsdown)
 			guard = page_align_down(fiber->stack - page_size);
 		else
 			guard = page_align_up(fiber->stack + fiber->stack_size);
@@ -1384,16 +1384,16 @@ cord_slab_cache(void)
 }
 
 static NOINLINE int
-check_stack_direction(void *prev_stack_frame)
+is_stack_growsdown(void *prev_stack_frame)
 {
-	return __builtin_frame_address(0) < prev_stack_frame ? -1: 1;
+	return __builtin_frame_address(0) < prev_stack_frame ? true : false;
 }
 
 void
 fiber_init(int (*invoke)(fiber_func f, va_list ap))
 {
 	page_size = sysconf(_SC_PAGESIZE);
-	stack_direction = check_stack_direction(__builtin_frame_address(0));
+	stack_growsdown = is_stack_growsdown(__builtin_frame_address(0));
 	fiber_invoke = invoke;
 	main_thread_id = pthread_self();
 	main_cord.loop = ev_default_loop(EVFLAG_AUTO | EVFLAG_ALLOCFD);
-- 
2.20.1