diff --git a/Objects/floatobject.c b/Objects/floatobject.c --- a/Objects/floatobject.c +++ b/Objects/floatobject.c @@ -16,53 +16,14 @@ /* Special free list - - Since some Python programs can spend much of their time allocating - and deallocating floats, these operations should be very fast. - Therefore we use a dedicated allocation scheme with a much lower - overhead (in space and time) than straight malloc(): a simple - dedicated free list, filled when necessary with memory from malloc(). - - block_list is a singly-linked list of all PyFloatBlocks ever allocated, - linked via their next members. PyFloatBlocks are never returned to the - system before shutdown (PyFloat_Fini). - free_list is a singly-linked list of available PyFloatObjects, linked via abuse of their ob_type members. */ -#define BLOCK_SIZE 1000 /* 1K less typical malloc overhead */ -#define BHEAD_SIZE 8 /* Enough for a 64-bit pointer */ -#define N_FLOATOBJECTS ((BLOCK_SIZE - BHEAD_SIZE) / sizeof(PyFloatObject)) - -struct _floatblock { - struct _floatblock *next; - PyFloatObject objects[N_FLOATOBJECTS]; -}; - -typedef struct _floatblock PyFloatBlock; - -static PyFloatBlock *block_list = NULL; +#define MAX_FREELIST 10 +static int n_freelist = 0; static PyFloatObject *free_list = NULL; -static PyFloatObject * -fill_free_list(void) -{ - PyFloatObject *p, *q; - /* XXX Float blocks escape the object heap. Use PyObject_MALLOC ??? */ - p = (PyFloatObject *) PyMem_MALLOC(sizeof(PyFloatBlock)); - if (p == NULL) - return (PyFloatObject *) PyErr_NoMemory(); - ((PyFloatBlock *)p)->next = block_list; - block_list = (PyFloatBlock *)p; - p = &((PyFloatBlock *)p)->objects[0]; - q = p + N_FLOATOBJECTS; - while (--q > p) - Py_TYPE(q) = (struct _typeobject *)(q-1); - Py_TYPE(q) = NULL; - return p + N_FLOATOBJECTS - 1; -} - double PyFloat_GetMax(void) { @@ -151,14 +112,16 @@ PyObject * PyFloat_FromDouble(double fval) { - register PyFloatObject *op; - if (free_list == NULL) { - if ((free_list = fill_free_list()) == NULL) - return NULL; + register PyFloatObject *op = free_list; + if (op != NULL) { + free_list = (PyFloatObject *)Py_TYPE(op); + n_freelist--; + } else { + op = PyObject_MALLOC(sizeof(PyFloatObject)); + if (!op) + return PyErr_NoMemory(); } /* Inline PyObject_New */ - op = free_list; - free_list = (PyFloatObject *)Py_TYPE(op); PyObject_INIT(op, &PyFloat_Type); op->ob_fval = fval; return (PyObject *) op; @@ -217,6 +180,11 @@ float_dealloc(PyFloatObject *op) { if (PyFloat_CheckExact(op)) { + if (n_freelist >= MAX_FREELIST) { + PyObject_FREE(op); + return; + } + n_freelist++; Py_TYPE(op) = (struct _typeobject *)free_list; free_list = op; } @@ -1932,96 +1900,21 @@ int PyFloat_ClearFreeList(void) { - PyFloatObject *p; - PyFloatBlock *list, *next; - int i; - int u; /* remaining unfreed floats per block */ - int freelist_size = 0; - - list = block_list; - block_list = NULL; + PyFloatObject *f = free_list, *next; + while (f) { + next = (PyFloatObject*) Py_TYPE(f); + PyObject_FREE(f); + f = next; + } free_list = NULL; - while (list != NULL) { - u = 0; - for (i = 0, p = &list->objects[0]; - i < N_FLOATOBJECTS; - i++, p++) { - if (PyFloat_CheckExact(p) && Py_REFCNT(p) != 0) - u++; - } - next = list->next; - if (u) { - list->next = block_list; - block_list = list; - for (i = 0, p = &list->objects[0]; - i < N_FLOATOBJECTS; - i++, p++) { - if (!PyFloat_CheckExact(p) || - Py_REFCNT(p) == 0) { - Py_TYPE(p) = (struct _typeobject *) - free_list; - free_list = p; - } - } - } - else { - PyMem_FREE(list); - } - freelist_size += u; - list = next; - } - return freelist_size; + n_freelist = 0; + return 0; } void PyFloat_Fini(void) { - PyFloatObject *p; - PyFloatBlock *list; - int i; - int u; /* total unfreed floats per block */ - - u = PyFloat_ClearFreeList(); - - if (!Py_VerboseFlag) - return; - fprintf(stderr, "# cleanup floats"); - if (!u) { - fprintf(stderr, "\n"); - } - else { - fprintf(stderr, - ": %d unfreed float%s\n", - u, u == 1 ? "" : "s"); - } - if (Py_VerboseFlag > 1) { - list = block_list; - while (list != NULL) { - for (i = 0, p = &list->objects[0]; - i < N_FLOATOBJECTS; - i++, p++) { - if (PyFloat_CheckExact(p) && - Py_REFCNT(p) != 0) { - char *buf = PyOS_double_to_string( - PyFloat_AS_DOUBLE(p), 'r', - 0, 0, NULL); - if (buf) { - /* XXX(twouters) cast - refcount to long - until %zd is - universally - available - */ - fprintf(stderr, - "# \n", - p, (long)Py_REFCNT(p), buf); - PyMem_Free(buf); - } - } - } - list = list->next; - } - } + (void)PyFloat_ClearFreeList(); } /*----------------------------------------------------------------------------