From 6cce23349147a2b8d4310d1ea9cb9e46da84c7e3 Mon Sep 17 00:00:00 2001
From: robertc <>
Date: Thu, 9 Jan 2003 19:27:14 +0000
Subject: [PATCH] extract async completion notification

---
 src/comm.cc          | 45 +++++++++++++++++++++++++++++++++++++++++++-
 src/comm.h           | 26 +++++++++++++++++++++++++
 src/fs/aufs/aiops.cc | 36 ++++-------------------------------
 3 files changed, 74 insertions(+), 33 deletions(-)

diff --git a/src/comm.cc b/src/comm.cc
index 51e6880e1f..acbbc80d00 100644
--- a/src/comm.cc
+++ b/src/comm.cc
@@ -1,6 +1,6 @@
 
 /*
- * $Id: comm.cc,v 1.360 2002/12/06 23:19:15 hno Exp $
+ * $Id: comm.cc,v 1.361 2003/01/09 12:27:14 robertc Exp $
  *
  * DEBUG: section 5     Socket Functions
  * AUTHOR: Harvest Derived
@@ -1885,3 +1885,46 @@ comm_accept(int fd, IOACB *handler, void *handler_data)
 	commSetSelect(fd, COMM_SELECT_READ, comm_accept_try, NULL, 0);
 #endif
 }
+
+void CommIO::Initialise()
+{
+    /* Initialize done pipe signal */
+    int DonePipe[2];
+    pipe(DonePipe);
+    DoneFD = DonePipe[1];
+    DoneReadFD = DonePipe[0];
+    fd_open(DonePipe[0], FD_PIPE, "async-io completetion event: main");
+    fd_open(DonePipe[1], FD_PIPE, "async-io completetion event: threads");
+    commSetNonBlocking(DonePipe[0]);
+    commSetNonBlocking(DonePipe[1]);
+    commSetSelect(DonePipe[0], COMM_SELECT_READ, NULLFDHandler, NULL, 0);
+    Initialised = true;
+}
+
+bool CommIO::Initialised = false;
+bool CommIO::DoneSignalled = false;
+int CommIO::DoneFD = -1;
+int CommIO::DoneReadFD = -1;
+
+void
+CommIO::FlushPipe()
+{
+    char buf[256];
+    read(DoneReadFD, buf, sizeof(buf));
+}
+
+void
+CommIO::NULLFDHandler(int fd, void *data)
+{
+    FlushPipe();
+    commSetSelect(fd, COMM_SELECT_READ, NULLFDHandler, NULL, 0);
+}
+
+void
+CommIO::ResetNotifications() 
+{
+    if (DoneSignalled) {
+	FlushPipe();
+	DoneSignalled = false;
+    }
+}
diff --git a/src/comm.h b/src/comm.h
index 7808d354c4..6ce1bfbf69 100644
--- a/src/comm.h
+++ b/src/comm.h
@@ -20,4 +20,30 @@ extern void comm_accept_setcheckperiod(int fd, int mdelay);
 
 extern void comm_write(int s, const char *buf, size_t len, IOWCB *callback, void *callback_data);
 
+/* Where should this belong? */
+class CommIO {
+public:
+  static inline void NotifyIOCompleted();
+  static void ResetNotifications();
+  static void Initialise();
+private:
+  static void NULLFDHandler(int, void *);
+  static void FlushPipe();
+  static bool Initialised;
+  static bool DoneSignalled;
+  static int DoneFD;
+  static int DoneReadFD;
+};
+
+/* Inline code. TODO: make structued approach to inlining */
+void
+CommIO::NotifyIOCompleted() {
+    if (!Initialised)
+	Initialise();
+    if (!DoneSignalled) {
+	DoneSignalled = true;
+	write(DoneFD, "!", 1);
+    }
+};
+
 #endif
diff --git a/src/fs/aufs/aiops.cc b/src/fs/aufs/aiops.cc
index 6dfda73166..d397b5ffa3 100644
--- a/src/fs/aufs/aiops.cc
+++ b/src/fs/aufs/aiops.cc
@@ -1,5 +1,5 @@
 /*
- * $Id: aiops.cc,v 1.20 2003/01/09 11:45:49 hno Exp $
+ * $Id: aiops.cc,v 1.21 2003/01/09 12:27:18 robertc Exp $
  *
  * DEBUG: section 43    AIOPS
  * AUTHOR: Stewart Forster <slf@connect.com.au>
@@ -46,6 +46,7 @@
 #if HAVE_SCHED_H
 #include	<sched.h>
 #endif
+#include "comm.h"
 
 #define RIDICULOUS_LENGTH	4096
 
@@ -146,9 +147,6 @@ static struct {
 
     NULL, &done_requests.head
 };
-static int done_fd = 0;
-static int done_fd_read = 0;
-static int done_signalled = 0;
 static pthread_attr_t globattr;
 #if HAVE_SCHED_H
 static struct sched_param globsched;
@@ -224,19 +222,10 @@ squidaio_xstrfree(char *str)
 	xfree(str);
 }
 
-static void
-squidaio_fdhandler(int fd, void *data)
-{
-    char junk[256];
-    read(done_fd_read, junk, sizeof(junk));
-    commSetSelect(fd, COMM_SELECT_READ, squidaio_fdhandler, NULL, 0);
-}
-
 static void
 squidaio_init(void)
 {
     int i;
-    int done_pipe[2];
     squidaio_thread_t *threadp;
 
     if (squidaio_initialised)
@@ -280,16 +269,6 @@ squidaio_init(void)
     done_queue.requests = 0;
     done_queue.blocked = 0;
 
-    /* Initialize done pipe signal */
-    pipe(done_pipe);
-    done_fd = done_pipe[1];
-    done_fd_read = done_pipe[0];
-    fd_open(done_pipe[0], FD_PIPE, "async-io completetion event: main");
-    fd_open(done_pipe[1], FD_PIPE, "async-io completetion event: threads");
-    commSetNonBlocking(done_pipe[0]);
-    commSetNonBlocking(done_pipe[1]);
-    commSetSelect(done_pipe[0], COMM_SELECT_READ, squidaio_fdhandler, NULL, 0);
-
     /* Create threads and get them to sit in their wait loop */
     squidaio_thread_pool = memPoolCreate("aio_thread", sizeof(squidaio_thread_t));
     assert(NUMTHREADS);
@@ -411,10 +390,7 @@ squidaio_thread_loop(void *ptr)
 	*done_queue.tailp = request;
 	done_queue.tailp = &request->next;
 	pthread_mutex_unlock(&done_queue.mutex);
-	if (!done_signalled) {
-	    done_signalled = 1;
-	    write(done_fd, "!", 1);
-	}
+	CommIO::NotifyIOCompleted();
 	threadp->requests++;
     }				/* while forever */
     return NULL;
@@ -829,11 +805,7 @@ squidaio_poll_done(void)
   AIO_REPOLL:
     request = done_requests.head;
     if (request == NULL && !polled) {
-	if (done_signalled) {
-	    char junk[256];
-	    read(done_fd_read, junk, sizeof(junk));
-	    done_signalled = 0;
-	}
+	CommIO::ResetNotifications();
 	squidaio_poll_queues();
 	polled = 1;
 	request = done_requests.head;
-- 
2.47.3