Fix single flip test

The single flip test requires to keep track of parity evolution across the loop
iterations. Keep it as a local variable so we don't end up adding unexisting
dependencies.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>

diff --git a/formal-model/urcu-controldataflow/urcu.spin b/formal-model/urcu-controldataflow/urcu.spin
index 484205a1dd999a9fd6c97f214e964b9aa2a884ff..6ec1655654367c75e78ca547dcbaf07fe4af73ca 100644 (file)
--- a/formal-model/urcu-controldataflow/urcu.spin
+++ b/formal-model/urcu-controldataflow/urcu.spin
@@ -592,7 +592,7 @@ non_atomic3_end:
 
                goto non_atomic3_skip;
 non_atomic3:
-               smp_mb_recv(i, j);      
+               smp_mb_recv(i, j);
                goto non_atomic3_end;
 non_atomic3_skip:
 
@@ -841,6 +841,11 @@ active proctype urcu_writer()
        byte i, j;
        byte tmp, tmp2, tmpa;
        byte old_gen;
+       byte cur_gp_val = 0;    /*
+                                * Keep a local trace of the current parity so
+                                * we don't add non-existing dependencies on the global
+                                * GP update. Needed to test single flip case.
+                                */
 
        wait_init_done();
 
@@ -884,11 +889,14 @@ progress_writer1:
                PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_SECOND_WAIT);
 #endif
 
-               do
+               do :: 1 ->
+               atomic {
+               if
                :: CONSUME_TOKENS(proc_urcu_writer,
                                  WRITE_PROD_NONE,
                                  WRITE_PROC_FIRST_MB) ->
-                       smp_mb_send(i, j);
+                       goto smp_mb_send1;
+smp_mb_send1_end:
                        PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_FIRST_MB);
 
                /* first flip */
@@ -911,9 +919,10 @@ progress_writer1:
                        ooo_mem(i);
                        /* ONLY WAITING FOR READER 0 */
                        tmp2 = READ_CACHED_VAR(urcu_active_readers[0]);
+                       cur_gp_val = cur_gp_val ^ RCU_GP_CTR_BIT;
                        if
                        :: (tmp2 & RCU_GP_CTR_NEST_MASK)
-                                       && ((tmp2 ^ RCU_GP_CTR_BIT) & RCU_GP_CTR_BIT) ->
+                                       && ((tmp2 ^ cur_gp_val) & RCU_GP_CTR_BIT) ->
                                PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_FIRST_WAIT_LOOP);
                        :: else ->
                                PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_FIRST_WAIT);
@@ -927,7 +936,8 @@ progress_writer1:
                                  | WRITE_PROC_FIRST_MB,        /* can be reordered before/after flips */
                                  0) ->
 #ifndef GEN_ERROR_WRITER_PROGRESS
-                       smp_mb_send(i, j);
+                       goto smp_mb_send2;
+smp_mb_send2_end:
 #else
                        ooo_mem(i);
 #endif
@@ -942,7 +952,6 @@ progress_writer1:
                                  | WRITE_PROC_FIRST_READ_GP
                                  | WRITE_PROC_FIRST_MB,
                                  WRITE_PROC_SECOND_READ_GP) ->
-                       //smp_mb_send(i, j);            //TEST
                        ooo_mem(i);
                        tmpa = READ_CACHED_VAR(urcu_gp_ctr);
                        PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_SECOND_READ_GP);
@@ -964,9 +973,10 @@ progress_writer1:
                        ooo_mem(i);
                        /* ONLY WAITING FOR READER 0 */
                        tmp2 = READ_CACHED_VAR(urcu_active_readers[0]);
+                       cur_gp_val = cur_gp_val ^ RCU_GP_CTR_BIT;
                        if
                        :: (tmp2 & RCU_GP_CTR_NEST_MASK)
-                                       && ((tmp2 ^ 0) & RCU_GP_CTR_BIT) ->
+                                       && ((tmp2 ^ cur_gp_val) & RCU_GP_CTR_BIT) ->
                                PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_SECOND_WAIT_LOOP);
                        :: else ->
                                PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_SECOND_WAIT);
@@ -982,7 +992,8 @@ progress_writer1:
                                  | WRITE_PROC_FIRST_MB,        /* can be reordered before/after flips */
                                  0) ->
 #ifndef GEN_ERROR_WRITER_PROGRESS
-                       smp_mb_send(i, j);
+                       goto smp_mb_send3;
+smp_mb_send3_end:
 #else
                        ooo_mem(i);
 #endif
@@ -999,12 +1010,15 @@ progress_writer1:
                                  | WRITE_PROC_SECOND_WRITE_GP
                                  | WRITE_PROC_FIRST_MB,
                                  WRITE_PROC_SECOND_MB) ->
-                       smp_mb_send(i, j);
+                       goto smp_mb_send4;
+smp_mb_send4_end:
                        PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_SECOND_MB);
 
                :: CONSUME_TOKENS(proc_urcu_writer, WRITE_PROC_ALL_TOKENS, 0) ->
                        CLEAR_TOKENS(proc_urcu_writer, WRITE_PROC_ALL_TOKENS_CLEAR);
                        break;
+               fi;
+               }
                od;
 
                write_lock = 0;
@@ -1028,6 +1042,25 @@ progress_writer2:
 #endif
                skip;
        od;
+
+       /* Non-atomic parts of the loop */
+       goto end;
+smp_mb_send1:
+       smp_mb_send(i, j);
+       goto smp_mb_send1_end;
+#ifndef GEN_ERROR_WRITER_PROGRESS
+smp_mb_send2:
+       smp_mb_send(i, j);
+       goto smp_mb_send2_end;
+smp_mb_send3:
+       smp_mb_send(i, j);
+       goto smp_mb_send3_end;
+#endif
+smp_mb_send4:
+       smp_mb_send(i, j);
+       goto smp_mb_send4_end;
+end:
+       skip;
 }
 
 /* no name clash please */