1: /*$Id: mal.c,v 1.57 2001/08/07 03:02:00 balay Exp $*/
  2: /*
  3:     Code that allows a user to dictate what malloc() PETSc uses.
  4: */
 5:  #include petsc.h
  6: #if defined(PETSC_HAVE_STDLIB_H)
  7: #include <stdlib.h>
  8: #endif
  9: #if defined(PETSC_HAVE_MALLOC_H)
 10: #include <malloc.h>
 11: #endif
 12: #include "petscfix.h"


 15: /*
 16:         We want to make sure that all mallocs of double or complex numbers are complex aligned.
 17:     1) on systems with memalign() we call that routine to get an aligned memory location
 18:     2) on systems without memalign() we 
 19:        - allocate one sizeof(PetscScalar) extra space
 20:        - we shift the pointer up slightly if needed to get PetscScalar aligned
 21:        - if shifted we store at ptr[-1] the amount of shift (plus a cookie)
 22: */
 23: #define SHIFT_COOKIE 456123

 25: /* need to use 16 and 8 below instead of sizeof() cause #if cannot handle sizeof() */
 26: #if !defined(PETSC_MEMALIGN)
 27: #  if defined(PETSC_USE_COMPLEX)
 28: #    define PETSC_MEMALIGN 16
 29: #  else
 30: #    define PETSC_MEMALIGN 8
 31: #  endif
 32: #endif

 34: #undef __FUNCT__  
 36: int PetscMallocAlign(size_t mem,int line,char *func,char *file,char *dir,void** result)
 37: {
 38:   if (mem == 0) SETERRQ(PETSC_ERR_MEM_MALLOC_0,"Cannot malloc size zero");
 39: #if defined(PETSC_HAVE_DOUBLE_ALIGN_MALLOC) && (PETSC_MEMALIGN == 8)
 40:   *result = malloc(mem);
 41: #elif defined(PETSC_HAVE_MEMALIGN)
 42:   *result = memalign(PETSC_MEMALIGN,mem);
 43: #else
 44:   {
 45:     int *ptr,shift;
 46:     /*
 47:       malloc space for two extra chunks and shift ptr 1 + enough to get it PetscScalar aligned
 48:     */
 49:     ptr = (int*)malloc(mem + 2*PETSC_MEMALIGN);
 50:     if (ptr) {
 51:       shift    = (int)(((unsigned long) ptr) % PETSC_MEMALIGN);
 52:       shift    = (2*PETSC_MEMALIGN - shift)/sizeof(int);
 53:       ptr     += shift;
 54:       ptr[-1]  = shift + SHIFT_COOKIE ;
 55:       *result  = (void*)ptr;
 56:     } else {
 57:       *result  = 0;
 58:     }
 59:   }
 60: #endif
 61:   if (!*result)  SETERRQ1(PETSC_ERR_MEM,"Memory requested %lu",(long)mem);
 62:   return 0;
 63: }

 65: #undef __FUNCT__  
 67: int PetscFreeAlign(void *ptr,int line,char *func,char *file,char *dir)
 68: {
 69:   int 0;

 71: #if (!(defined(PETSC_HAVE_DOUBLE_ALIGN_MALLOC) && (PETSC_MEMALIGN == 8)) && !defined(PETSC_HAVE_MEMALIGN))
 72:   int shift;
 73:   /*
 74:        Previous int tells us how many ints the pointer has been shifted from
 75:     the original address provided by the system malloc().
 76:   */
 77:   shift = ((int *)ptr)[-1] - SHIFT_COOKIE;
 78:   if (shift > PETSC_MEMALIGN-1) return PetscError(line,func,file,dir,1,1,"Likely memory corruption in heap");
 79:   ptr   = (void*)(((int*)ptr) - shift);
 80: #endif

 82: #if defined(PETSC_HAVE_FREE_RETURN_INT)
 83:   free(ptr);
 84:   if (ierr) {
 85:     return PetscError(line,func,file,dir,1,1,"System free returned error %dn",ierr);
 86:   }
 87: #else 
 88:   free(ptr);
 89: #endif
 90:   return ierr;
 91: }

 93: /*
 94:         We never use the system free directly because on many machines it 
 95:     does not return an error code.
 96: */
 97: #undef __FUNCT__  
 99: int PetscFreeDefault(void *ptr,int line,char *func,char *file,char *dir)
100: {
101: #if defined(PETSC_HAVE_FREE_RETURN_INT)
102:   int free(ptr);
103:   if (ierr) {
104:     return PetscError(line,func,file,dir,1,1,"System free returned error %dn",ierr);
105:   }
106: #else 
107:   free(ptr);
108: #endif
109:   return 0;
110: }

112: int  (*PetscTrMalloc)(size_t,int,char*,char*,char*,void**) = PetscMallocAlign;
113: int  (*PetscTrFree)(void *,int,char*,char *,char*)         = PetscFreeAlign;

115: PetscTruth petscsetmallocvisited = PETSC_FALSE;

117: #undef __FUNCT__  
119: /*@C
120:    PetscSetMalloc - Sets the routines used to do mallocs and frees.
121:    This routine MUST be called before PetscInitialize() and may be
122:    called only once.

124:    Not Collective

126:    Input Parameters:
127: +  malloc - the malloc routine
128: -  free - the free routine

130:    Level: developer

132:    Concepts: malloc
133:    Concepts: memory^allocation 

135: @*/
136: int PetscSetMalloc(int (*imalloc)(size_t,int,char*,char*,char*,void**),
137:                    int (*ifree)(void*,int,char*,char*,char*))
138: {
140:   if (petscsetmallocvisited && (imalloc != PetscTrMalloc || ifree != PetscTrFree)) SETERRQ(PETSC_ERR_SUP,"cannot call multiple times");
141:   PetscTrMalloc               = imalloc;
142:   PetscTrFree                 = ifree;
143:   petscsetmallocvisited       = PETSC_TRUE;
144:   return(0);
145: }

147: #undef __FUNCT__  
149: /*@C
150:    PetscClearMalloc - Resets the routines used to do mallocs and frees to the 
151:         defaults.

153:    Not Collective

155:    Level: developer

157:    Notes:
158:     In general one should never run a PETSc program with different malloc() and 
159:     free() settings for different parts; this is because one NEVER wants to 
160:     free() an address that was malloced by a different memory management system

162: @*/
163: int PetscClearMalloc(void)
164: {
166:   PetscTrMalloc         = PetscMallocAlign;
167:   PetscTrFree           = PetscFreeAlign;
168:   petscsetmallocvisited = PETSC_FALSE;
169:   return(0);
170: }