xref: /petsc/src/sys/classes/viewer/impls/vu/petscvu.c (revision 3ba1676111f5c958fe6c2729b46ca4d523958bb3)
15c6c1daeSBarry Smith 
2af0996ceSBarry Smith #include <petsc/private/viewerimpl.h> /*I     "petscsys.h"   I*/
35c6c1daeSBarry Smith 
45c6c1daeSBarry Smith #define QUEUESTRINGSIZE 1024
55c6c1daeSBarry Smith 
65c6c1daeSBarry Smith typedef struct _PrintfQueue *PrintfQueue;
75c6c1daeSBarry Smith struct _PrintfQueue {
85c6c1daeSBarry Smith   char        string[QUEUESTRINGSIZE];
95c6c1daeSBarry Smith   PrintfQueue next;
105c6c1daeSBarry Smith };
115c6c1daeSBarry Smith 
125c6c1daeSBarry Smith typedef struct {
135c6c1daeSBarry Smith   FILE         *fd;
145c6c1daeSBarry Smith   PetscFileMode mode; /* The mode in which to open the file */
155c6c1daeSBarry Smith   char         *filename;
165c6c1daeSBarry Smith   PetscBool     vecSeen; /* The flag indicating whether any vector has been viewed so far */
175c6c1daeSBarry Smith   PrintfQueue   queue, queueBase;
185c6c1daeSBarry Smith   int           queueLength;
195c6c1daeSBarry Smith } PetscViewer_VU;
205c6c1daeSBarry Smith 
21d71ae5a4SJacob Faibussowitsch static PetscErrorCode PetscViewerFileClose_VU(PetscViewer viewer)
22d71ae5a4SJacob Faibussowitsch {
235c6c1daeSBarry Smith   PetscViewer_VU *vu = (PetscViewer_VU *)viewer->data;
245c6c1daeSBarry Smith 
255c6c1daeSBarry Smith   PetscFunctionBegin;
2648a46eb9SPierre Jolivet   if (vu->vecSeen) PetscCall(PetscViewerVUPrintDeferred(viewer, "};\n\n"));
279566063dSJacob Faibussowitsch   PetscCall(PetscViewerVUFlushDeferred(viewer));
289566063dSJacob Faibussowitsch   PetscCall(PetscFClose(PetscObjectComm((PetscObject)viewer), vu->fd));
290298fd71SBarry Smith   vu->fd = NULL;
309566063dSJacob Faibussowitsch   PetscCall(PetscFree(vu->filename));
31*3ba16761SJacob Faibussowitsch   PetscFunctionReturn(PETSC_SUCCESS);
325c6c1daeSBarry Smith }
335c6c1daeSBarry Smith 
34d71ae5a4SJacob Faibussowitsch PetscErrorCode PetscViewerDestroy_VU(PetscViewer viewer)
35d71ae5a4SJacob Faibussowitsch {
365c6c1daeSBarry Smith   PetscViewer_VU *vu = (PetscViewer_VU *)viewer->data;
375c6c1daeSBarry Smith 
385c6c1daeSBarry Smith   PetscFunctionBegin;
399566063dSJacob Faibussowitsch   PetscCall(PetscViewerFileClose_VU(viewer));
409566063dSJacob Faibussowitsch   PetscCall(PetscFree(vu));
412e956fe4SStefano Zampini   PetscCall(PetscObjectComposeFunction((PetscObject)viewer, "PetscViewerFileSetName_C", NULL));
422e956fe4SStefano Zampini   PetscCall(PetscObjectComposeFunction((PetscObject)viewer, "PetscViewerFileGetName_C", NULL));
432e956fe4SStefano Zampini   PetscCall(PetscObjectComposeFunction((PetscObject)viewer, "PetscViewerFileSetMode_C", NULL));
442e956fe4SStefano Zampini   PetscCall(PetscObjectComposeFunction((PetscObject)viewer, "PetscViewerFileGetMode_C", NULL));
45*3ba16761SJacob Faibussowitsch   PetscFunctionReturn(PETSC_SUCCESS);
465c6c1daeSBarry Smith }
475c6c1daeSBarry Smith 
48d71ae5a4SJacob Faibussowitsch PetscErrorCode PetscViewerFlush_VU(PetscViewer viewer)
49d71ae5a4SJacob Faibussowitsch {
505c6c1daeSBarry Smith   PetscViewer_VU *vu = (PetscViewer_VU *)viewer->data;
515c6c1daeSBarry Smith   PetscMPIInt     rank;
525c6c1daeSBarry Smith   int             err;
535c6c1daeSBarry Smith 
545c6c1daeSBarry Smith   PetscFunctionBegin;
559566063dSJacob Faibussowitsch   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)viewer), &rank));
56dd400576SPatrick Sanan   if (rank == 0) {
575c6c1daeSBarry Smith     err = fflush(vu->fd);
5828b400f6SJacob Faibussowitsch     PetscCheck(!err, PETSC_COMM_SELF, PETSC_ERR_SYS, "fflush() failed on file");
595c6c1daeSBarry Smith   }
60*3ba16761SJacob Faibussowitsch   PetscFunctionReturn(PETSC_SUCCESS);
615c6c1daeSBarry Smith }
625c6c1daeSBarry Smith 
63d71ae5a4SJacob Faibussowitsch static PetscErrorCode PetscViewerFileSetMode_VU(PetscViewer viewer, PetscFileMode mode)
64d71ae5a4SJacob Faibussowitsch {
657e4fd573SVaclav Hapla   PetscViewer_VU *vu = (PetscViewer_VU *)viewer->data;
667e4fd573SVaclav Hapla 
677e4fd573SVaclav Hapla   PetscFunctionBegin;
687e4fd573SVaclav Hapla   vu->mode = mode;
69*3ba16761SJacob Faibussowitsch   PetscFunctionReturn(PETSC_SUCCESS);
707e4fd573SVaclav Hapla }
717e4fd573SVaclav Hapla 
72d71ae5a4SJacob Faibussowitsch static PetscErrorCode PetscViewerFileGetMode_VU(PetscViewer viewer, PetscFileMode *type)
73d71ae5a4SJacob Faibussowitsch {
747e4fd573SVaclav Hapla   PetscViewer_VU *vu = (PetscViewer_VU *)viewer->data;
757e4fd573SVaclav Hapla 
767e4fd573SVaclav Hapla   PetscFunctionBegin;
777e4fd573SVaclav Hapla   *type = vu->mode;
78*3ba16761SJacob Faibussowitsch   PetscFunctionReturn(PETSC_SUCCESS);
797e4fd573SVaclav Hapla }
807e4fd573SVaclav Hapla 
81d71ae5a4SJacob Faibussowitsch static PetscErrorCode PetscViewerFileGetName_VU(PetscViewer viewer, const char **name)
82d71ae5a4SJacob Faibussowitsch {
835c6c1daeSBarry Smith   PetscViewer_VU *vu = (PetscViewer_VU *)viewer->data;
845c6c1daeSBarry Smith 
855c6c1daeSBarry Smith   PetscFunctionBegin;
865c6c1daeSBarry Smith   *name = vu->filename;
87*3ba16761SJacob Faibussowitsch   PetscFunctionReturn(PETSC_SUCCESS);
885c6c1daeSBarry Smith }
895c6c1daeSBarry Smith 
90d71ae5a4SJacob Faibussowitsch static PetscErrorCode PetscViewerFileSetName_VU(PetscViewer viewer, const char name[])
91d71ae5a4SJacob Faibussowitsch {
925c6c1daeSBarry Smith   PetscViewer_VU *vu = (PetscViewer_VU *)viewer->data;
935c6c1daeSBarry Smith   char            fname[PETSC_MAX_PATH_LEN];
945c6c1daeSBarry Smith   int             rank;
955c6c1daeSBarry Smith 
965c6c1daeSBarry Smith   PetscFunctionBegin;
97*3ba16761SJacob Faibussowitsch   if (!name) PetscFunctionReturn(PETSC_SUCCESS);
989566063dSJacob Faibussowitsch   PetscCall(PetscViewerFileClose_VU(viewer));
999566063dSJacob Faibussowitsch   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)viewer), &rank));
100*3ba16761SJacob Faibussowitsch   if (rank != 0) PetscFunctionReturn(PETSC_SUCCESS);
1019566063dSJacob Faibussowitsch   PetscCall(PetscStrallocpy(name, &vu->filename));
1029566063dSJacob Faibussowitsch   PetscCall(PetscFixFilename(name, fname));
1035c6c1daeSBarry Smith   switch (vu->mode) {
104d71ae5a4SJacob Faibussowitsch   case FILE_MODE_READ:
105d71ae5a4SJacob Faibussowitsch     vu->fd = fopen(fname, "r");
106d71ae5a4SJacob Faibussowitsch     break;
107d71ae5a4SJacob Faibussowitsch   case FILE_MODE_WRITE:
108d71ae5a4SJacob Faibussowitsch     vu->fd = fopen(fname, "w");
109d71ae5a4SJacob Faibussowitsch     break;
110d71ae5a4SJacob Faibussowitsch   case FILE_MODE_APPEND:
111d71ae5a4SJacob Faibussowitsch     vu->fd = fopen(fname, "a");
112d71ae5a4SJacob Faibussowitsch     break;
1135c6c1daeSBarry Smith   case FILE_MODE_UPDATE:
1145c6c1daeSBarry Smith     vu->fd = fopen(fname, "r+");
115a297a907SKarl Rupp     if (!vu->fd) vu->fd = fopen(fname, "w+");
1165c6c1daeSBarry Smith     break;
1175c6c1daeSBarry Smith   case FILE_MODE_APPEND_UPDATE:
1185c6c1daeSBarry Smith     /* I really want a file which is opened at the end for updating,
1195c6c1daeSBarry Smith        not a+, which opens at the beginning, but makes writes at the end.
1205c6c1daeSBarry Smith     */
1215c6c1daeSBarry Smith     vu->fd = fopen(fname, "r+");
122a297a907SKarl Rupp     if (!vu->fd) vu->fd = fopen(fname, "w+");
123*3ba16761SJacob Faibussowitsch     else {
124*3ba16761SJacob Faibussowitsch       int ret = fseek(vu->fd, 0, SEEK_END);
125*3ba16761SJacob Faibussowitsch       PetscCheck(!ret, PETSC_COMM_SELF, PETSC_ERR_LIB, "fseek() failed with error code %d", ret);
126*3ba16761SJacob Faibussowitsch     }
1275c6c1daeSBarry Smith     break;
128d71ae5a4SJacob Faibussowitsch   default:
129d71ae5a4SJacob Faibussowitsch     SETERRQ(PetscObjectComm((PetscObject)viewer), PETSC_ERR_SUP, "Unsupported file mode %s", PetscFileModes[vu->mode]);
1305c6c1daeSBarry Smith   }
1315c6c1daeSBarry Smith 
13228b400f6SJacob Faibussowitsch   PetscCheck(vu->fd, PETSC_COMM_SELF, PETSC_ERR_FILE_OPEN, "Cannot open PetscViewer file: %s", fname);
1335c6c1daeSBarry Smith #if defined(PETSC_USE_LOG)
134*3ba16761SJacob Faibussowitsch   PetscCall(PetscLogObjectState((PetscObject)viewer, "File: %s", name));
1355c6c1daeSBarry Smith #endif
136*3ba16761SJacob Faibussowitsch   PetscFunctionReturn(PETSC_SUCCESS);
1375c6c1daeSBarry Smith }
1385c6c1daeSBarry Smith 
139811af0c4SBarry Smith /*MC
140811af0c4SBarry Smith    PETSCVIEWERVU - A viewer that prints to a VU file
141811af0c4SBarry Smith 
142811af0c4SBarry Smith   Level: beginner
143811af0c4SBarry Smith 
144d1f92df0SBarry Smith .seealso: [](sec_viewers), `PetscViewerVUFlushDeferred()`, `PetscViewerVUGetPointer()`, `PetscViewerVUSetVecSeen()`, `PetscViewerVUGetVecSeen()`,
145811af0c4SBarry Smith           `PetscViewerVUPrintDeferred()`, `PetscViewerVUFlushDeferred()`
146811af0c4SBarry Smith M*/
147d71ae5a4SJacob Faibussowitsch PETSC_EXTERN PetscErrorCode PetscViewerCreate_VU(PetscViewer viewer)
148d71ae5a4SJacob Faibussowitsch {
1495c6c1daeSBarry Smith   PetscViewer_VU *vu;
1505c6c1daeSBarry Smith 
1515c6c1daeSBarry Smith   PetscFunctionBegin;
1524dfa11a4SJacob Faibussowitsch   PetscCall(PetscNew(&vu));
1535c6c1daeSBarry Smith   viewer->data = (void *)vu;
1545c6c1daeSBarry Smith 
1555c6c1daeSBarry Smith   viewer->ops->destroy          = PetscViewerDestroy_VU;
1565c6c1daeSBarry Smith   viewer->ops->flush            = PetscViewerFlush_VU;
157559f443fSBarry Smith   viewer->ops->getsubviewer     = NULL;
158559f443fSBarry Smith   viewer->ops->restoresubviewer = NULL;
1595c6c1daeSBarry Smith 
1600298fd71SBarry Smith   vu->fd          = NULL;
1615c6c1daeSBarry Smith   vu->mode        = FILE_MODE_WRITE;
1620298fd71SBarry Smith   vu->filename    = NULL;
1635c6c1daeSBarry Smith   vu->vecSeen     = PETSC_FALSE;
1640298fd71SBarry Smith   vu->queue       = NULL;
1650298fd71SBarry Smith   vu->queueBase   = NULL;
1665c6c1daeSBarry Smith   vu->queueLength = 0;
1675c6c1daeSBarry Smith 
1689566063dSJacob Faibussowitsch   PetscCall(PetscObjectComposeFunction((PetscObject)viewer, "PetscViewerFileSetName_C", PetscViewerFileSetName_VU));
1699566063dSJacob Faibussowitsch   PetscCall(PetscObjectComposeFunction((PetscObject)viewer, "PetscViewerFileGetName_C", PetscViewerFileGetName_VU));
1709566063dSJacob Faibussowitsch   PetscCall(PetscObjectComposeFunction((PetscObject)viewer, "PetscViewerFileSetMode_C", PetscViewerFileSetMode_VU));
1719566063dSJacob Faibussowitsch   PetscCall(PetscObjectComposeFunction((PetscObject)viewer, "PetscViewerFileGetMode_C", PetscViewerFileGetMode_VU));
172*3ba16761SJacob Faibussowitsch   PetscFunctionReturn(PETSC_SUCCESS);
1735c6c1daeSBarry Smith }
1745c6c1daeSBarry Smith 
1755c6c1daeSBarry Smith /*@C
176811af0c4SBarry Smith   PetscViewerVUGetPointer - Extracts the file pointer from a `PETSCVIEWERVU` `PetscViewer`.
1775c6c1daeSBarry Smith 
1785c6c1daeSBarry Smith   Not Collective
1795c6c1daeSBarry Smith 
1805c6c1daeSBarry Smith   Input Parameter:
181811af0c4SBarry Smith . viewer - The `PetscViewer`
1825c6c1daeSBarry Smith 
1835c6c1daeSBarry Smith   Output Parameter:
1845c6c1daeSBarry Smith . fd     - The file pointer
1855c6c1daeSBarry Smith 
1865c6c1daeSBarry Smith   Level: intermediate
1875c6c1daeSBarry Smith 
188d1f92df0SBarry Smith .seealso: [](sec_viewers), `PETSCVIEWERVU`, `PetscViewerASCIIGetPointer()`
1895c6c1daeSBarry Smith @*/
190d71ae5a4SJacob Faibussowitsch PetscErrorCode PetscViewerVUGetPointer(PetscViewer viewer, FILE **fd)
191d71ae5a4SJacob Faibussowitsch {
1925c6c1daeSBarry Smith   PetscViewer_VU *vu = (PetscViewer_VU *)viewer->data;
1935c6c1daeSBarry Smith 
1945c6c1daeSBarry Smith   PetscFunctionBegin;
1955c6c1daeSBarry Smith   PetscValidHeaderSpecific(viewer, PETSC_VIEWER_CLASSID, 1);
1965c6c1daeSBarry Smith   PetscValidPointer(fd, 2);
1975c6c1daeSBarry Smith   *fd = vu->fd;
198*3ba16761SJacob Faibussowitsch   PetscFunctionReturn(PETSC_SUCCESS);
1995c6c1daeSBarry Smith }
2005c6c1daeSBarry Smith 
2015c6c1daeSBarry Smith /*@C
2025c6c1daeSBarry Smith   PetscViewerVUSetVecSeen - Sets the flag which indicates whether we have viewed
2035c6c1daeSBarry Smith   a vector. This is usually called internally rather than by a user.
2045c6c1daeSBarry Smith 
2055c6c1daeSBarry Smith   Not Collective
2065c6c1daeSBarry Smith 
2075c6c1daeSBarry Smith   Input Parameters:
208811af0c4SBarry Smith + viewer  - The `PETSCVIEWERVU` `PetscViewer`
2095c6c1daeSBarry Smith - vecSeen - The flag which indicates whether we have viewed a vector
2105c6c1daeSBarry Smith 
211811af0c4SBarry Smith   Level: developer
2125c6c1daeSBarry Smith 
213d1f92df0SBarry Smith .seealso: [](sec_viewers), `PETSCVIEWERVU`, `PetscViewerVUGetVecSeen()`
2145c6c1daeSBarry Smith @*/
215d71ae5a4SJacob Faibussowitsch PetscErrorCode PetscViewerVUSetVecSeen(PetscViewer viewer, PetscBool vecSeen)
216d71ae5a4SJacob Faibussowitsch {
2175c6c1daeSBarry Smith   PetscViewer_VU *vu = (PetscViewer_VU *)viewer->data;
2185c6c1daeSBarry Smith 
2195c6c1daeSBarry Smith   PetscFunctionBegin;
2205c6c1daeSBarry Smith   vu->vecSeen = vecSeen;
221*3ba16761SJacob Faibussowitsch   PetscFunctionReturn(PETSC_SUCCESS);
2225c6c1daeSBarry Smith }
2235c6c1daeSBarry Smith 
2245c6c1daeSBarry Smith /*@C
2255c6c1daeSBarry Smith   PetscViewerVUGetVecSeen - Gets the flag which indicates whether we have viewed
2265c6c1daeSBarry Smith   a vector. This is usually called internally rather than by a user.
2275c6c1daeSBarry Smith 
2285c6c1daeSBarry Smith   Not Collective
2295c6c1daeSBarry Smith 
2305c6c1daeSBarry Smith   Input Parameter:
231811af0c4SBarry Smith . viewer  - The `PETSCVIEWERVU` `PetscViewer`
2325c6c1daeSBarry Smith 
2335c6c1daeSBarry Smith   Output Parameter:
2345c6c1daeSBarry Smith . vecSeen - The flag which indicates whether we have viewed a vector
2355c6c1daeSBarry Smith 
2365c6c1daeSBarry Smith   Level: advanced
2375c6c1daeSBarry Smith 
238d1f92df0SBarry Smith .seealso: [](sec_viewers), `PETSCVIEWERVU`, `PetscViewerVUGetVecSeen()`
2395c6c1daeSBarry Smith @*/
240d71ae5a4SJacob Faibussowitsch PetscErrorCode PetscViewerVUGetVecSeen(PetscViewer viewer, PetscBool *vecSeen)
241d71ae5a4SJacob Faibussowitsch {
2425c6c1daeSBarry Smith   PetscViewer_VU *vu = (PetscViewer_VU *)viewer->data;
2435c6c1daeSBarry Smith 
2445c6c1daeSBarry Smith   PetscFunctionBegin;
2455c6c1daeSBarry Smith   PetscValidHeaderSpecific(viewer, PETSC_VIEWER_CLASSID, 1);
246dadcf809SJacob Faibussowitsch   PetscValidBoolPointer(vecSeen, 2);
2475c6c1daeSBarry Smith   *vecSeen = vu->vecSeen;
248*3ba16761SJacob Faibussowitsch   PetscFunctionReturn(PETSC_SUCCESS);
2495c6c1daeSBarry Smith }
2505c6c1daeSBarry Smith 
2515c6c1daeSBarry Smith /*@C
2525c6c1daeSBarry Smith   PetscViewerVUPrintDeferred - Prints to the deferred write cache instead of the file.
2535c6c1daeSBarry Smith 
2545c6c1daeSBarry Smith   Not Collective
2555c6c1daeSBarry Smith 
2565c6c1daeSBarry Smith   Input Parameters:
257811af0c4SBarry Smith + viewer - The `PETSCVIEWERVU` `PetscViewer`
2585c6c1daeSBarry Smith - format - The format string
2595c6c1daeSBarry Smith 
2605c6c1daeSBarry Smith   Level: intermediate
2615c6c1daeSBarry Smith 
262d1f92df0SBarry Smith .seealso: [](sec_viewers), `PETSCVIEWERVU`, `PetscViewerVUFlushDeferred()`
2635c6c1daeSBarry Smith @*/
264d71ae5a4SJacob Faibussowitsch PetscErrorCode PetscViewerVUPrintDeferred(PetscViewer viewer, const char format[], ...)
265d71ae5a4SJacob Faibussowitsch {
2665c6c1daeSBarry Smith   PetscViewer_VU *vu = (PetscViewer_VU *)viewer->data;
2675c6c1daeSBarry Smith   va_list         Argp;
2685c6c1daeSBarry Smith   size_t          fullLength;
2695c6c1daeSBarry Smith   PrintfQueue     next;
2705c6c1daeSBarry Smith 
2715c6c1daeSBarry Smith   PetscFunctionBegin;
2729566063dSJacob Faibussowitsch   PetscCall(PetscNew(&next));
2735c6c1daeSBarry Smith   if (vu->queue) {
2745c6c1daeSBarry Smith     vu->queue->next = next;
2755c6c1daeSBarry Smith     vu->queue       = next;
2760298fd71SBarry Smith     vu->queue->next = NULL;
2775c6c1daeSBarry Smith   } else {
2785c6c1daeSBarry Smith     vu->queueBase = vu->queue = next;
2795c6c1daeSBarry Smith   }
2805c6c1daeSBarry Smith   vu->queueLength++;
2815c6c1daeSBarry Smith 
2825c6c1daeSBarry Smith   va_start(Argp, format);
2839566063dSJacob Faibussowitsch   PetscCall(PetscArrayzero(next->string, QUEUESTRINGSIZE));
2849566063dSJacob Faibussowitsch   PetscCall(PetscVSNPrintf(next->string, QUEUESTRINGSIZE, format, &fullLength, Argp));
2855c6c1daeSBarry Smith   va_end(Argp);
286*3ba16761SJacob Faibussowitsch   PetscFunctionReturn(PETSC_SUCCESS);
2875c6c1daeSBarry Smith }
2885c6c1daeSBarry Smith 
2895c6c1daeSBarry Smith /*@C
2905c6c1daeSBarry Smith   PetscViewerVUFlushDeferred - Flushes the deferred write cache to the file.
2915c6c1daeSBarry Smith 
2925c6c1daeSBarry Smith   Not Collective
2935c6c1daeSBarry Smith 
2945c6c1daeSBarry Smith   Input Parameter:
295811af0c4SBarry Smith . viewer - The `PETSCVIEWERVU` `PetscViewer`
2965c6c1daeSBarry Smith 
2975c6c1daeSBarry Smith   Level: intermediate
2985c6c1daeSBarry Smith 
299d1f92df0SBarry Smith .seealso: [](sec_viewers), `PETSCVIEWERVU`, `PetscViewerVUPrintDeferred()`
3005c6c1daeSBarry Smith @*/
301d71ae5a4SJacob Faibussowitsch PetscErrorCode PetscViewerVUFlushDeferred(PetscViewer viewer)
302d71ae5a4SJacob Faibussowitsch {
3035c6c1daeSBarry Smith   PetscViewer_VU *vu   = (PetscViewer_VU *)viewer->data;
3045c6c1daeSBarry Smith   PrintfQueue     next = vu->queueBase;
3055c6c1daeSBarry Smith   PrintfQueue     previous;
3065c6c1daeSBarry Smith   int             i;
3075c6c1daeSBarry Smith 
3085c6c1daeSBarry Smith   PetscFunctionBegin;
3095c6c1daeSBarry Smith   for (i = 0; i < vu->queueLength; i++) {
310*3ba16761SJacob Faibussowitsch     PetscCall(PetscFPrintf(PetscObjectComm((PetscObject)viewer), vu->fd, "%s", next->string));
3115c6c1daeSBarry Smith     previous = next;
3125c6c1daeSBarry Smith     next     = next->next;
3139566063dSJacob Faibussowitsch     PetscCall(PetscFree(previous));
3145c6c1daeSBarry Smith   }
3150298fd71SBarry Smith   vu->queue       = NULL;
3165c6c1daeSBarry Smith   vu->queueLength = 0;
317*3ba16761SJacob Faibussowitsch   PetscFunctionReturn(PETSC_SUCCESS);
3185c6c1daeSBarry Smith }
319