X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=lib%2Fpoll-loop.h;h=6614ebe58f7a3a81e2600f9514f3bc3d24629823;hb=bbb8dee92d639331e8bd81823638267dcc895396;hp=89c8e573e71d51e5212035dae2ac78d5634b707b;hpb=d474bd01bbdbbbdc94de525cef4099cb06cabf22;p=sliver-openvswitch.git

diff --git a/lib/poll-loop.h b/lib/poll-loop.h
index 89c8e573e..6614ebe58 100644
--- a/lib/poll-loop.h
+++ b/lib/poll-loop.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2008, 2009 Nicira Networks.
+ * Copyright (c) 2008, 2009, 2010, 2011, 2013 Nicira, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,7 +16,7 @@
 
 /* High-level wrapper around the "poll" system call.
  *
- * Intended usage is for the program's main loop to go about its business
+ * The intended usage is for each thread's main loop to go about its business
  * servicing whatever events it needs to.  Then, when it runs out of immediate
  * tasks, it calls each subordinate module's "wait" function, which in turn
  * calls one (or more) of the functions poll_fd_wait(), poll_immediate_wake(),
@@ -24,27 +24,51 @@
  * occurs.  Then the main loop calls poll_block(), which blocks until one of
  * the registered events happens.
  *
- * There is also some support for autonomous subroutines that are executed by
- * poll_block() when a file descriptor becomes ready.  To prevent these
- * routines from starving if events are continuously ready, the application
- * should bound the amount of work it does between poll_block() calls. */
-
+ *
+ * Thread-safety
+ * =============
+ *
+ * The poll set is per-thread, so all functions in this module are thread-safe.
+ */
 #ifndef POLL_LOOP_H
 #define POLL_LOOP_H 1
 
 #include <poll.h>
+#include "util.h"
+
+#ifdef  __cplusplus
+extern "C" {
+#endif
+
+
+/* Schedule events to wake up the following poll_block().
+ *
+ * The poll_loop logs the 'where' argument to each function at "debug" level
+ * when an event causes a wakeup.  Ordinarily, it is automatically filled in
+ * with the location in the source of the call, and the caller should therefore
+ * omit it.  But, if the function you are implementing is very generic, so that
+ * its location in the source would not be very helpful for debugging, you can
+ * avoid the macro expansion and pass a different argument, e.g.:
+ *      (poll_fd_wait)(fd, events, where);
+ * See timer_wait() for an example.
+ */
+void poll_fd_wait(int fd, short int events, const char *where);
+#define poll_fd_wait(fd, events) poll_fd_wait(fd, events, SOURCE_LOCATOR)
+
+void poll_timer_wait(long long int msec, const char *where);
+#define poll_timer_wait(msec) poll_timer_wait(msec, SOURCE_LOCATOR)
 
-struct poll_waiter;
+void poll_timer_wait_until(long long int msec, const char *where);
+#define poll_timer_wait_until(msec) poll_timer_wait_until(msec, SOURCE_LOCATOR)
 
-/* Schedule events to wake up the following poll_block(). */
-struct poll_waiter *poll_fd_wait(int fd, short int events);
-void poll_timer_wait(int msec);
-void poll_immediate_wake(void);
+void poll_immediate_wake(const char *where);
+#define poll_immediate_wake() poll_immediate_wake(SOURCE_LOCATOR)
 
 /* Wait until an event occurs. */
 void poll_block(void);
 
-/* Cancel a file descriptor callback or event. */
-void poll_cancel(struct poll_waiter *);
+#ifdef  __cplusplus
+}
+#endif
 
 #endif /* poll-loop.h */