From: Daniel Stodden <daniel.stodden@citrix.com>
Date: Tue, 15 Feb 2011 09:37:45 +0000 (-0800)
Subject: PR-1053: Further reduce tapdisk-stream.
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=0c862c559750c84a63a8e11b3fa02c01ef59bcd0;p=people%2Fdstodden%2Fblktap.git

PR-1053: Further reduce tapdisk-stream.

Drop the pipe end and custom event. Reissue requests right after prior
completion instead.

Signed-off-by: Daniel Stodden <daniel.stodden@citrix.com>
---

diff --git a/drivers/tapdisk-stream.c b/drivers/tapdisk-stream.c
index 1403707..e90c87f 100644
--- a/drivers/tapdisk-stream.c
+++ b/drivers/tapdisk-stream.c
@@ -79,14 +79,12 @@ struct tapdisk_stream {
 	td_stream_req_t                  reqs[TD_STREAM_MAX_REQS];
 	td_stream_req_t                 *free[TD_STREAM_MAX_REQS];
 	int                              n_free;
-
-	int                              poll_fd;
-	event_id_t                       poll_id;
 };
 
 static unsigned int tapdisk_stream_count;
 
 static void tapdisk_stream_close_image(td_stream_t *);
+static void tapdisk_stream_queue_requests(td_stream_t *);
 
 static void
 usage(const char *app, int err)
@@ -253,7 +251,7 @@ tapdisk_stream_complete_request(td_stream_t *s, td_stream_req_t *req,
 		return;
 	}
 
-	tapdisk_server_mask_event(s->poll_id, 0);
+	tapdisk_stream_queue_requests(s);
 }
 
 static void
@@ -306,10 +304,8 @@ tapdisk_stream_queue_requests(td_stream_t *s)
 		td_stream_req_t *req;
 
 		req = tapdisk_stream_alloc_req(s);
-		if (!req) {
-			tapdisk_server_mask_event(s->poll_id, 1);
+		if (!req)
 			break;
-		}
 
 		tapdisk_stream_queue_request(s, req);
 	}
@@ -396,59 +392,6 @@ void
 __tapdisk_stream_event_cb(event_id_t id, char mode, void *arg)
 {
 	td_stream_t *s = arg;
-	tapdisk_stream_queue_requests(s);
-}
-
-static void
-tapdisk_stream_destroy_event(struct tapdisk_stream *s)
-{
-	if (s->poll_id >= 0) {
-		tapdisk_server_unregister_event(s->poll_id);
-		s->poll_id = 0;
-	}
-
-	if (s->poll_fd >= 0) {
-		close(s->poll_fd);
-		s->poll_fd = -1;
-	}
-}
-
-static int
-tapdisk_stream_create_event(td_stream_t *s)
-{
-	int fd[2];
-	int err;
-
-	s->poll_id = -1;
-	s->poll_fd = -1;
-
-	err = pipe(fd);
-	if (err) {
-		err = -errno;
-		goto fail;
-	}
-
-	s->poll_fd = fd[0];
-
-	err = close(fd[1]);
-	BUG_ON(err);
-
-	s->poll_id =
-		tapdisk_server_register_event(SCHEDULER_POLL_READ_FD,
-					      s->poll_fd, 0,
-					      __tapdisk_stream_event_cb, s);
-	if (s->poll_id < 0)
-		goto fail;
-
-	return 0;
-
-fail:
-	if (err)
-		fprintf(stderr, "failed to register event: %d\n", err);
-
-	tapdisk_stream_destroy_event(s);
-
-	return err;
 }
 
 static int
@@ -466,8 +409,6 @@ tapdisk_stream_open_fds(struct tapdisk_stream *s)
 static void
 tapdisk_stream_close(struct tapdisk_stream *s)
 {
-	tapdisk_stream_destroy_event(s);
-
 	tapdisk_stream_destroy_reqs(s);
 
 	tapdisk_stream_close_image(s);
@@ -497,8 +438,6 @@ tapdisk_stream_open(struct tapdisk_stream *s, const char *name,
 		err = tapdisk_stream_set_position(s, count, skip);
 	if (!err)
 		err = tapdisk_stream_create_reqs(s);
-	if (!err)
-		err = tapdisk_stream_create_event(s);
 
 	if (err)
 		tapdisk_stream_close(s);