X-Git-Url: http://plrg.eecs.uci.edu/git/?p=cdsspec-compiler.git;a=blobdiff_plain;f=benchmark%2Fmpmc-queue%2Fmpmc-queue.h;h=046a248d0ef09e272b134c1c1be753eb7e7d37b9;hp=ff6a168f1c248cc2db457f8fa7b7da8dc818f91a;hb=d1aff50233aef12d3f8376bb4646de39f4112560;hpb=7537757f9cbddcfa61076053bea0bddad28e37ad;ds=sidebyside

diff --git a/benchmark/mpmc-queue/mpmc-queue.h b/benchmark/mpmc-queue/mpmc-queue.h
index ff6a168..046a248 100644
--- a/benchmark/mpmc-queue/mpmc-queue.h
+++ b/benchmark/mpmc-queue/mpmc-queue.h
@@ -134,7 +134,7 @@ public:
 		// (*1)
 		rl::backoff bo;
 		while (true) {
-			/**** Inadmissibility ****/
+			/**** Inadmissibility (testcase2.c) ****/
 			int written = m_written.load(mo_acquire);
 			if ((written & MASK) != wr) {
 				thrd_yield();
@@ -173,7 +173,7 @@ public:
 		@End
 	*/
 	void read_consume(t_element *bin) {
-		/**** Inadmissibility ****/
+		/**** Inadmissibility (testcase1.c) ****/
 		m_read.fetch_add(1,mo_release);
 		/**
 			@Begin
@@ -214,6 +214,14 @@ public:
 				return NULL;
 			}
 			
+			// FIXME: Theoretically we have a bug here, it is not so likely to
+			// happen!!! The following acq_rel can not guarantee that the load
+			// acquire on m_read to read the most recent value. However, it can
+			// decrease the chance of the load acquire of m_read to read a too
+			// old value. Same as the case in read_fetch(). Maybe making things
+			// SC can fix it. We can run testcase3.c to expose this bug (set the
+			// array size  = 1, the MASK = 1).
+			
 			/**** Inadmissibility (testcase3.cc, MASK = 1, size = 1) ****/
 			bool succ = m_rdwr.compare_exchange_weak(rdwr,(rd<<16) |
 				((wr+1)&MASK),mo_acq_rel);
@@ -241,7 +249,7 @@ public:
 		// (*1)
 		rl::backoff bo;
 		while (true) {
-			/**** Inadmissibility ****/
+			/**** Inadmissibility (testcase1.c) ****/
 			int read = m_read.load(mo_acquire);
 			if ((read & MASK) != rd)
 				thrd_yield();
@@ -273,19 +281,19 @@ public:
 	/**
 		@Begin
 		@Interface: Publish 
-		@Commit_point_set: Publish_W_RMW
+		@Commit_point_set: PublishFetchAdd
 		@ID: (call_id_t) bin 
 		//@Action: model_print("Publish: %d\n", bin);
 		@End
 	*/
 	void write_publish(t_element *bin)
 	{
-		/**** Inadmissibility ****/
+		/**** Inadmissibility (testcase2.c) ****/
 		int tmp = m_written.fetch_add(1,mo_release);
 		/**
 			@Begin
 			@Commit_point_define_check: true
-			@Label: Publish_W_RMW
+			@Label: PublishFetchAdd
 			@End
 		*/
 		printf("publish: m_written=%d\n", tmp + 1);