support non-timed eventflag

eventflag.c

@@ -1,5 +1,5 @@
 /*
- * eventflag.c - Eventflag with timeout
+ * eventflag.c - Eventflag with/without timeout
  *
  * Copyright (C) 2013 Flying Stone Technology
  * Author: NIIBE Yutaka <gniibe@fsij.org>
@@ -31,31 +31,64 @@
 #include <chopstx.h>
 #include <eventflag.h>
 
+enum {
+  EVENTFLAG_ERR_WAIT = CHOPSTX_ERR_JOIN + 1,
+  EVENTFLAG_ERR_TIMED_WAIT,
+};
+
+
 void
-eventflag_init (struct event_flag *ev, chopstx_t owner)
+eventflag_init (struct event_flag *ev, chopstx_t sleeper)
 {
-  ev->owner = owner;
-  ev->wait_usec = 0;
+  ev->sleeper = sleeper;
+
+  if (sleeper)
+    ev->u.wait_usec = 0;
+  else
+    chopstx_cond_init (&ev->u.cond);
+
   ev->flag = 0;
   chopstx_mutex_init (&ev->mutex);
 }
 
 
+eventmask_t
+eventflag_wait (struct event_flag *ev)
+{
+  int n;
+
+  if (ev->sleeper)
+    chx_fatal (EVENTFLAG_ERR_WAIT);
+
+  chopstx_mutex_lock (&ev->mutex);
+  if (!ev->flag)
+    chopstx_cond_wait (&ev->cond, &ev->mutex);
+
+  n = __builtin_ffs ((ev->flag & m));
+  ev->flag &= ~(1 << (n - 1));
+  chopstx_mutex_unlock (&ev->mutex);
+
+  return (1 << (n - 1));
+}
+
 eventmask_t
 eventflag_wait_timeout (struct event_flag *ev, uint32_t usec)
 {
   eventmask_t em = 0;
   int n;
 
+  if (ev->sleeper == 0)
+    chx_fatal (EVENTFLAG_ERR_TIMED_WAIT);
+
   chopstx_mutex_lock (&ev->mutex);
 
   if (!ev->flag)
     {
-      ev->wait_usec = usec;
+      ev->u.wait_usec = usec;
       chopstx_mutex_unlock (&ev->mutex);
-      chopstx_usec_wait_var (&ev->wait_usec);
+      chopstx_usec_wait_var (&ev->u.wait_usec);
       chopstx_mutex_lock (&ev->mutex);
-      ev->wait_usec = 0;
+      ev->u.wait_usec = 0;
     }
 
   n = __builtin_ffs (ev->flag);
@@ -75,10 +108,15 @@ eventflag_signal (struct event_flag *ev, eventmask_t m)
 {
   chopstx_mutex_lock (&ev->mutex);
   ev->flag |= m;
-  if (ev->wait_usec)
+  if (ev->sleeper)
     {
-      ev->wait_usec = 0;
-      chopstx_wakeup_usec_wait (ev->owner);
+      if (ev->u.wait_usec)
+	{
+	  ev->u.wait_usec = 0;
+	  chopstx_wakeup_usec_wait (ev->sleeper);
+	}
     }
+  else
+    chopstx_cond_signal (&ev->cond);
   chopstx_mutex_unlock (&ev->mutex);
 }

eventflag.h

@@ -1,10 +1,13 @@
 typedef uint32_t eventmask_t;
 
 struct eventflag {
-  chopstx_t owner;
-  uint32_t wait_usec;
+  chopstx_t sleeper;
   eventmask_t flag;
   chopstx_mutex_t mutex;
+  union {
+    uint32_t wait_usec;
+    chopstx_cond_t cond;
+  } u;
 };
 
 void eventflag_init (struct eventflag *ev, chopstx_t owner);