Date: 2013-07-02T14:38:49+00:00

Actual source code: mal.c
petsc-3.4.2 2013-07-02

      2: /*
      3:     Code that allows a user to dictate what malloc() PETSc uses.
      4: */
      5: #include <petscsys.h>             /*I   "petscsys.h"   I*/
      6: #if defined(PETSC_HAVE_MALLOC_H)
      7: #include <malloc.h>
      8: #endif

     10: /*
     11:         We want to make sure that all mallocs of double or complex numbers are complex aligned.
     12:     1) on systems with memalign() we call that routine to get an aligned memory location
     13:     2) on systems without memalign() we
     14:        - allocate one sizeof(PetscScalar) extra space
     15:        - we shift the pointer up slightly if needed to get PetscScalar aligned
     16:        - if shifted we store at ptr[-1] the amount of shift (plus a classid)
     17: */
     18: #define SHIFT_CLASSID 456123

     22: PetscErrorCode  PetscMallocAlign(size_t mem,int line,const char func[],const char file[],const char dir[],void **result)
     23: {
     24: #if defined(PETSC_HAVE_DOUBLE_ALIGN_MALLOC) && (PETSC_MEMALIGN == 8)
     25:   *result = malloc(mem);
     26: #elif defined(PETSC_HAVE_MEMALIGN)
     27:   *result = memalign(PETSC_MEMALIGN,mem);
     28: #else
     29:   {
     30:     int *ptr,shift;
     31:     /*
     32:       malloc space for two extra chunks and shift ptr 1 + enough to get it PetscScalar aligned
     33:     */
     34:     ptr = (int*)malloc(mem + 2*PETSC_MEMALIGN);
     35:     if (ptr) {
     36:       shift        = (int)(((PETSC_UINTPTR_T) ptr) % PETSC_MEMALIGN);
     37:       shift        = (2*PETSC_MEMALIGN - shift)/sizeof(int);
     38:       ptr[shift-1] = shift + SHIFT_CLASSID;
     39:       ptr         += shift;
     40:       *result      = (void*)ptr;
     41:     } else {
     42:       *result      = 0;
     43:     }
     44:   }
     45: #endif
     46:   if (!*result) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_MEM,"Memory requested %.0f",(PetscLogDouble)mem);
     47:   return 0;
     48: }

     52: PetscErrorCode  PetscFreeAlign(void *ptr,int line,const char func[],const char file[],const char dir[])
     53: {
     54: #if (!(defined(PETSC_HAVE_DOUBLE_ALIGN_MALLOC) && (PETSC_MEMALIGN == 8)) && !defined(PETSC_HAVE_MEMALIGN))
     55:   int shift;
     56:   /*
     57:        Previous int tells us how many ints the pointer has been shifted from
     58:     the original address provided by the system malloc().
     59:   */
     60:   shift = *(((int*)ptr)-1) - SHIFT_CLASSID;
     61:   if (shift > PETSC_MEMALIGN-1) return PetscError(PETSC_COMM_SELF,line,func,file,dir,PETSC_ERR_PLIB,PETSC_ERROR_INITIAL,"Likely memory corruption in heap");
     62:   if (shift < 0) return PetscError(PETSC_COMM_SELF,line,func,file,dir,PETSC_ERR_PLIB,PETSC_ERROR_INITIAL,"Likely memory corruption in heap");
     63:   ptr = (void*)(((int*)ptr) - shift);
     64: #endif

     66: #if defined(PETSC_HAVE_FREE_RETURN_INT)
     67:   int err = free(ptr);
     68:   if (err) return PetscError(PETSC_COMM_SELF,line,func,file,dir,PETSC_ERR_PLIB,PETSC_ERROR_INITIAL,"System free returned error %d\n",err);
     69: #else
     70:   free(ptr);
     71: #endif
     72:   return 0;
     73: }

     75: /*
     76:         We never use the system free directly because on many machines it
     77:     does not return an error code.
     78: */
     81: PetscErrorCode  PetscFreeDefault(void *ptr,int line,char *func,char *file,char *dir)
     82: {
     83: #if defined(PETSC_HAVE_FREE_RETURN_INT)
     84:   int err = free(ptr);
     85:   if (err) return PetscError(PETSC_COMM_SELF,line,func,file,dir,PETSC_ERR_PLIB,PETSC_ERROR_INITIAL,"System free returned error %d\n",err);
     86: #else
     87:   free(ptr);
     88: #endif
     89:   return 0;
     90: }

     92: PetscErrorCode (*PetscTrMalloc)(size_t,int,const char[],const char[],const char[],void**) = PetscMallocAlign;
     93: PetscErrorCode (*PetscTrFree)(void*,int,const char[],const char[],const char[])           = PetscFreeAlign;

     95: PetscBool petscsetmallocvisited = PETSC_FALSE;

     99: /*@C
    100:    PetscMallocSet - Sets the routines used to do mallocs and frees.
    101:    This routine MUST be called before PetscInitialize() and may be
    102:    called only once.

    104:    Not Collective

    106:    Input Parameters:
    107: +  malloc - the malloc routine
    108: -  free - the free routine

    110:    Level: developer

    112:    Concepts: malloc
    113:    Concepts: memory^allocation

    115: @*/
    116: PetscErrorCode  PetscMallocSet(PetscErrorCode (*imalloc)(size_t,int,const char[],const char[],const char[],void**),
    117:                                               PetscErrorCode (*ifree)(void*,int,const char[],const char[],const char[]))
    118: {
    120:   if (petscsetmallocvisited && (imalloc != PetscTrMalloc || ifree != PetscTrFree)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"cannot call multiple times");
    121:   PetscTrMalloc         = imalloc;
    122:   PetscTrFree           = ifree;
    123:   petscsetmallocvisited = PETSC_TRUE;
    124:   return(0);
    125: }

    129: /*@C
    130:    PetscMallocClear - Resets the routines used to do mallocs and frees to the
    131:         defaults.

    133:    Not Collective

    135:    Level: developer

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

    142: @*/
    143: PetscErrorCode  PetscMallocClear(void)
    144: {
    146:   PetscTrMalloc         = PetscMallocAlign;
    147:   PetscTrFree           = PetscFreeAlign;
    148:   petscsetmallocvisited = PETSC_FALSE;
    149:   return(0);
    150: }