/[MITgcm]/MITgcm/eesupp/src/barrier.F
ViewVC logotype

Diff of /MITgcm/eesupp/src/barrier.F

Parent Directory Parent Directory | Revision Log Revision Log | View Revision Graph Revision Graph | View Patch Patch

revision 1.1 by cnh, Wed Apr 22 19:15:30 1998 UTC revision 1.6 by adcroft, Tue May 18 17:39:21 1999 UTC
# Line 1  Line 1 
1  C $Id$  C $Header$
2    
3  #include "CPP_EEOPTIONS.h"  #include "CPP_EEOPTIONS.h"
4    
5        SUBROUTINE BARRIER_INIT        SUBROUTINE BARRIER_INIT
6          IMPLICIT NONE
7    
8    #include "SIZE.h"
9  #include "EEPARAMS.h"  #include "EEPARAMS.h"
10  #include "EESUPPORT.h"  #include "EESUPPORT.h"
11  #include "BARRIER.h"  #include "BARRIER.h"
# Line 44  C     | coherency over process caches an Line 47  C     | coherency over process caches an
47  C     | Also we have to be a bit careful regarding sequential    |  C     | Also we have to be a bit careful regarding sequential    |
48  C     | consistency - or lack of it. At the moment the code      |  C     | consistency - or lack of it. At the moment the code      |
49  C     | assumes a total store order memory model, which some     |  C     | assumes a total store order memory model, which some     |
50  C     | machines don't have! However, I have yet to find a       |  C     | machines do not have! However, I have yet to find a      |
51  C     | problem with this I think because the tolerances in      |  C     | problem with this I think because the tolerances in      |
52  C     | terms of memory ordering i.e. a little bit of reordering |  C     | terms of memory ordering i.e. a little bit of reordering |
53  C     | probably won't break the barrier mechanism!              |  C     | probably will not break the barrier mechanism!           |
54  C     | On non-cache coherent systems e.g. T3E we need to use    |  C     | On non-cache coherent systems e.g. T3E we need to use    |
55  C     | a library function to do barriers.                       |  C     | a library function to do barriers.                       |
56  C     | Note - The PANIC tests can be removed for working code   |  C     | Note - The PANIC tests can be removed for working code   |
# Line 60  C     |        lines to make your code " Line 63  C     |        lines to make your code "
63  C     |        stopping in these PANIC blocks then something is  |  C     |        stopping in these PANIC blocks then something is  |
64  C     |        wrong with your program and it needs to be fixed. |  C     |        wrong with your program and it needs to be fixed. |
65  C     \==========================================================/  C     \==========================================================/
66    
67    #include "SIZE.h"
68  #include "EEPARAMS.h"  #include "EEPARAMS.h"
69  #include "EESUPPORT.h"  #include "EESUPPORT.h"
70  #include "BARRIER.h"  #include "BARRIER.h"
# Line 75  C     I     - Loop counter Line 80  C     I     - Loop counter
80        INTEGER I        INTEGER I
81    
82  CcnhDebugStarts  CcnhDebugStarts
83  C     IF ( myThid .EQ. 1 ) THEN  C      WRITE(myThid,*) ' Barrier entered '
 C      WRITE(0,*) ' Barrier entered '  
 C     ENDIF  
84  CcnhDebugEnds  CcnhDebugEnds
85    
86  C--   Check that thread number is expected range  C--   Check that thread number is expected range
87        IF ( myThid .LT. 1 .OR. myThid .GT. nThreads ) THEN        IF ( myThid .LT. 1 .OR. myThid .GT. nThreads ) THEN
88         WRITE(0,*) '!!!!!!! PANIC !!!!!!! CATASTROPHIC ERROR'         WRITE(0,*) '!!!!!!! PANIC !!!!!!! CATASTROPHIC ERROR'
89         WRITE(0,*) '!!!!!!! PANIC !!!!!!! in S/R BARRIER  myThid = ', myThid, ' nThreads = ', nThreads         WRITE(0,*) '!!!!!!! PANIC !!!!!!! in S/R BARRIER  myThid = ',
90         &  myThid, ' nThreads = ', nThreads
91         STOP 'ABNROMAL END: S/R BARRIER'         STOP 'ABNROMAL END: S/R BARRIER'
92        ENDIF        ENDIF
93    
94  C--   When every threads key1 is valid thread 1 will open door1.  C--   When every threads key1 is valid thread 1 will open door1.
95        IF ( key1(1,myThid) .EQ. VALID ) THEN        IF ( key1(1,myThid) .EQ. VALID ) THEN
96         WRITE(0,*) '!!!!!!! PANIC !!!!!!! CATASTROPHIC ERROR'         WRITE(0,*) '!!!!!!! PANIC !!!!!!! CATASTROPHIC ERROR'
97         WRITE(0,*) '!!!!!!! PANIC !!!!!!! in S/R BARRIER  myThid = ', myThid, ' key1 already validated'         WRITE(0,*) '!!!!!!! PANIC !!!!!!! in S/R BARRIER  myThid = ',
98         &  myThid, ' key1 already validated'
99         STOP 'ABNROMAL END: S/R BARRIER'         STOP 'ABNROMAL END: S/R BARRIER'
100        ENDIF        ENDIF
101        key1(1,myThid) = VALID        key1(1,myThid) = VALID
# Line 129  C--   door3 because they have to go thro Line 134  C--   door3 because they have to go thro
134  C--   When every threads key2 is valid thread 1 will open door2.  C--   When every threads key2 is valid thread 1 will open door2.
135  C     Notes  C     Notes
136  C     =====  C     =====
 C      I don't understand memory ordering and sequential consistency.  
137  C     I think that to work with any memory model ( i.e. relaxed,  C     I think that to work with any memory model ( i.e. relaxed,
138  C     partial store, total store) the variables key1, key2 and key3  C     partial store, total store) the variables key1, key2 and key3
139  C     might need to be set to invalid by thread 1.  C     might need to be set to invalid by thread 1.
140  C      C    
141        IF ( key2(1,myThid) .EQ. VALID ) THEN        IF ( key2(1,myThid) .EQ. VALID ) THEN
142         WRITE(0,*) '!!!!!!! PANIC !!!!!!! CATASTROPHIC ERROR'         WRITE(0,*) '!!!!!!! PANIC !!!!!!! CATASTROPHIC ERROR'
143         WRITE(0,*) '!!!!!!! PANIC !!!!!!! in S/R BARRIER  myThid = ', myThid, ' key2 already validated'         WRITE(0,*) '!!!!!!! PANIC !!!!!!! in S/R BARRIER  myThid = ',
144         &  myThid, ' key2 already validated'
145         STOP 'ABNROMAL END: S/R BARRIER'         STOP 'ABNROMAL END: S/R BARRIER'
146        ENDIF        ENDIF
147        key2(1,myThid) = VALID        key2(1,myThid) = VALID
# Line 171  C--   door1 because they have to go thro Line 176  C--   door1 because they have to go thro
176  C--   When every threads key3 is valid thread 1 will open door3.  C--   When every threads key3 is valid thread 1 will open door3.
177        IF ( key3(1,myThid) .EQ. VALID ) THEN        IF ( key3(1,myThid) .EQ. VALID ) THEN
178         WRITE(0,*) '!!!!!!! PANIC !!!!!!! CATASTROPHIC ERROR'         WRITE(0,*) '!!!!!!! PANIC !!!!!!! CATASTROPHIC ERROR'
179         WRITE(0,*) '!!!!!!! PANIC !!!!!!! in S/R BARRIER  myThid = ', myThid, ' key3 already validated'         WRITE(0,*) '!!!!!!! PANIC !!!!!!! in S/R BARRIER  myThid = ',
180         &  myThid, ' key3 already validated'
181         STOP 'ABNROMAL END: S/R BARRIER'         STOP 'ABNROMAL END: S/R BARRIER'
182        ENDIF        ENDIF
183        key3(1,myThid) = VALID        key3(1,myThid) = VALID
# Line 203  C--   door2 because they have to go thro Line 209  C--   door2 because they have to go thro
209        ENDIF        ENDIF
210    
211  CcnhDebugStarts  CcnhDebugStarts
212  C     IF ( myThid .EQ. 1 ) THEN  C      WRITE(myThid,*) ' Barrier exited '
 C      WRITE(0,*) ' Barrier exited '  
 C     ENDIF  
213  CcnhDebugEnds  CcnhDebugEnds
214            
215        RETURN        RETURN
216        END        END
   
 C $Id$  
Legend:
Removed from v.1.1  
changed lines
  Added in v.1.6
  ViewVC Help
Powered by ViewVC 1.1.22