Add buffer count for fiber_sem to improve the performance.

lib_fiber/c/include/fiber/fiber_sem.h

@@ -21,6 +21,14 @@ typedef struct ACL_FIBER_SEM ACL_FIBER_SEM;
 FIBER_API ACL_FIBER_SEM* acl_fiber_sem_create2(int num, unsigned flags);
 #define ACL_FIBER_SEM_F_ASYNC	(1 << 0)	/* If notifying in async mode */
 
+/**
+ * Create one fiber semaphore with the specified buff count and flags.
+ * @param num {int} the initial value of the semaphore, must >= 0
+ * @param buf {int} the buffed count before signal the waiters.
+ * @param flags {unsigned} the flags defined as ACL_FIBER_SEM_F_XXX
+ */
+FIBER_API ACL_FIBER_SEM* acl_fiber_sem_create3(int num, int buf, unsigned flags);
+
 FIBER_API ACL_FIBER_SEM* acl_fiber_sem_create(int num);
 
 /**

lib_fiber/c/src/sync/fiber_sem.c

@@ -6,6 +6,7 @@
 
 struct ACL_FIBER_SEM {
 	int num;
+	int buf;
 	unsigned flags;
 	RING waiting;
 	unsigned long tid;
@@ -17,11 +18,18 @@ ACL_FIBER_SEM *acl_fiber_sem_create(int num)
 }
 
 ACL_FIBER_SEM *acl_fiber_sem_create2(int num, unsigned flags)
+{
+	int buf = (flags & ACL_FIBER_SEM_F_ASYNC) ? 50000000 : 0;
+	return acl_fiber_sem_create3(num, buf, flags);
+}
+
+ACL_FIBER_SEM *acl_fiber_sem_create3(int num, int buf, unsigned flags)
 {
 	ACL_FIBER_SEM *sem = (ACL_FIBER_SEM *) mem_malloc(sizeof(ACL_FIBER_SEM));
 
 	sem->tid   = 0;
 	sem->num   = num;
+	sem->buf   = buf;
 	sem->flags = flags;
 	ring_init(&sem->waiting);
 	return sem;
@@ -178,6 +186,9 @@ int acl_fiber_sem_post(ACL_FIBER_SEM *sem)
 	sem->num++;
 
 	if ((ready = FIRST_FIBER(&sem->waiting)) == NULL) {
+		if (sem->num >= sem->buf) {
+			acl_fiber_yield();
+		}
 		return sem->num;
 	}
 
@@ -187,7 +198,7 @@ int acl_fiber_sem_post(ACL_FIBER_SEM *sem)
 	/* Help the fiber to be wakeup to decrease the sem number. */
 	num = sem->num--;
 
-	if (!(sem->flags & ACL_FIBER_SEM_F_ASYNC)) {
+	if (num >= sem->buf) {
 		acl_fiber_yield();
 	}
 

lib_fiber/cpp/include/fiber/fiber_sem.hpp

@@ -15,6 +15,7 @@ typedef enum {
 class FIBER_CPP_API fiber_sem {
 public:
 	explicit fiber_sem(int max, fiber_sem_attr_t attr = fiber_sem_t_async);
+	explicit fiber_sem(int max, int buf);
 	~fiber_sem();
 
 	int wait(int ms = -1);
@@ -55,6 +56,10 @@ class fiber_sbox : public box<T> {
 	: sem_(0, async ? fiber_sem_t_async : fiber_sem_t_sync)
 	, free_obj_(free_obj) {}
 
+	explicit fiber_sbox(int buf, bool free_obj = true)
+	: sem_(0, buf)
+	, free_obj_(free_obj) {}
+
 	~fiber_sbox() { clear(free_obj_); }
 
 	// @override
@@ -143,6 +148,9 @@ class fiber_sbox2 : public box2<T> {
 	explicit fiber_sbox2(bool async = true)
 	: sem_(0, async ? fiber_sem_t_async : fiber_sem_t_sync) {}
 
+	explicit fiber_sbox2(int buf)
+	: sem_(0, buf) {}
+
 	~fiber_sbox2() {}
 
 	// @override

lib_fiber/cpp/src/fiber_sem.cpp

@@ -14,6 +14,11 @@ fiber_sem::fiber_sem(int max, fiber_sem_attr_t attr)
 	sem_ = acl_fiber_sem_create2(max, flags);
 }
 
+fiber_sem::fiber_sem(int max, int buf)
+{
+	sem_ = acl_fiber_sem_create3(max, buf, 0);
+}
+
 fiber_sem::~fiber_sem()
 {
 	acl_fiber_sem_free(sem_);

lib_fiber/samples-c++1x/fiber_box/main.cpp

@@ -12,19 +12,18 @@ static void usage(const char* procname)
             " -n count\r\n"
             " -c fibers\r\n"
             " -t box_type[sbox2|tbox2]"
-            " -S [if in sync mode for sbox2]\r\n", procname);
+            " -b buf_count\r\n", procname);
 }
 
 int main(int argc, char *argv[])
 {
-    int  ch, n = 10, c = 1;
+    int  ch, n = 10, c = 1, buf = 0;
     std::string type = "sbox2";
-    bool sync = false;
 
     acl::acl_cpp_init();
     acl::log::stdout_open(true);
 
-    while ((ch = getopt(argc, argv, "hn:t:c:S")) > 0) {
+    while ((ch = getopt(argc, argv, "hn:t:c:b:")) > 0) {
         switch (ch) {
             case 'h':
                 usage(argv[0]);
@@ -38,8 +37,8 @@ int main(int argc, char *argv[])
             case 'c':
                 c = atoi(optarg);
                 break;
-            case 'S':
-                sync = true; 
+            case 'b':
+		buf = atoi(optarg);
                 break;
             default:
                 break;
@@ -49,7 +48,7 @@ int main(int argc, char *argv[])
     std::shared_ptr<acl::box2<int>> box;
 
     if (type == "sbox2") {
-        box = std::make_shared<acl::fiber_sbox2<int>>(!sync);
+        box = std::make_shared<acl::fiber_sbox2<int>>(buf);
     } else if (type == "tbox2") {
         box = std::make_shared<acl::fiber_tbox2<int>>();
     } else {
@@ -83,7 +82,7 @@ int main(int argc, char *argv[])
         };
     }
 
-	acl::fiber::schedule();
+    acl::fiber::schedule();
 
     struct timeval end;
     gettimeofday(&end, nullptr);