PERFORCE change 123584 for review

[Andrew Turner]

http://perforce.freebsd.org/chv.cgi?CH=123584

Change 123584 by andrew at andrew_hermies on 2007/07/16 11:29:13

	When using kqueue to check for updates only check to directory that changed rather than all directories

Affected files ...

.. //depot/projects/soc2007/andrew-update/backend/facund-be.c#13 edit

Differences ...

==== //depot/projects/soc2007/andrew-update/backend/facund-be.c#13 (text+ko) ====

@@ -138,7 +138,7 @@
 
 		/* Create an event to look for files being added to the dir */
 		EV_SET(&events[pos], dir_fd[pos], EVFILT_VNODE, EV_ADD,
-		    NOTE_WRITE | NOTE_DELETE | NOTE_EXTEND, 0, NULL);
+		    NOTE_WRITE | NOTE_DELETE | NOTE_EXTEND, 0, (void *)pos);
 	}
 
 	use_kqueue = 1;
@@ -150,13 +150,47 @@
 	kq = kqueue();
 	if (kq == -1)
 		use_kqueue = 0;
+
+	pos = dir_count;
+
+	/*
+	 * This is the main loop to check for updates. It will
+	 * either wait for file system activity on the update
+	 * directories of just sleep for a fixed amount of time
+	 * then scan all directories.
+	 */
 	while(1) {
-		for (pos = 0; base_dirs[pos] != NULL; pos++) {
-			if (has_update(base_dirs[pos])) {
-				printf("Updates found in %s\n", base_dirs[pos]);
-				found_updates = 1;
+		assert(pos <= dir_count);
+		if (use_kqueue == 0 || pos == dir_count) {
+			/*
+			 * We are using sleep to wait for updates or
+			 * kqueue timed out. This means we have to check
+			 * all directories to see if they have an update.
+			 */
+			for (pos = 0; base_dirs[pos] != NULL; pos++) {
+				if (has_update(base_dirs[pos])) {
+					printf("Updates found in %s\n",
+					    base_dirs[pos]);
+					found_updates = 1;
+				}
+			}
+			/* Check we have looked at all directories */
+			assert(pos == dir_count);
+		} else {
+			/*
+			 * We are using kqueue to wait for updates.
+			 * pos will contain the position in base_dirs of
+			 * the directory that had file system activity.
+			 */
+			if (pos < dir_count) {
+				if (has_update(base_dirs[pos])) {
+					printf("Updates found in %s\n",
+					    base_dirs[pos]);
+					found_updates = 1;
+				}
 			}
 		}
+		pos = dir_count;
 
 		/*
 		 * Wait for any disk activity to
@@ -170,9 +204,20 @@
 		/* Wait for posible updates */
 		if (use_kqueue == 1) {
 			/* Wait for posible updates ready to be installed */
-			if (kevent(kq, events, dir_count, &changes, 1, &timeout)
-			    == -1) {
-				use_kqueue = 1;
+			int error;
+
+			error = kevent(kq, events, dir_count, &changes, 1,
+			    &timeout);
+
+			if (error == -1) {
+				/*
+				 * There was an error in
+				 * kqueue, change to sleep
+				 */
+				use_kqueue = 0;
+			} else if (error > 0) {
+				/* Read in the item that changed */
+				pos = (size_t)changes.udata;
 			}
 		} else {
 			sleep(default_check_period);