From f9d0b1256fd5a9ae90fa8e8418bd450ec6b7f5f2 Mon Sep 17 00:00:00 2001 From: Antoine Pitrou Date: Sun, 9 Dec 2012 14:28:26 +0100 Subject: [PATCH] Issue #13390: New function :func:`sys.getallocatedblocks()` returns the number of memory blocks currently allocated. Also, the ``-R`` option to regrtest uses this function to guard against memory allocation leaks. --- Doc/library/sys.rst | 14 ++++++++++++ Include/objimpl.h | 2 ++ Lib/test/regrtest.py | 54 ++++++++++++++++++++++++++++++-------------- Lib/test/support.py | 2 +- Lib/test/test_sys.py | 24 ++++++++++++++++++++ Misc/NEWS | 6 +++++ Objects/obmalloc.c | 21 ++++++++++++++++- Python/pythonrun.c | 7 +++--- Python/sysmodule.c | 15 ++++++++++++ 9 files changed, 123 insertions(+), 22 deletions(-) diff --git a/Doc/library/sys.rst b/Doc/library/sys.rst index c327f21ee07..ee1f2b23a6d 100644 --- a/Doc/library/sys.rst +++ b/Doc/library/sys.rst @@ -393,6 +393,20 @@ always available. .. versionadded:: 3.1 +.. function:: getallocatedblocks() + + Return the number of memory blocks currently allocated by the interpreter, + regardless of their size. This function is mainly useful for debugging + small memory leaks. Because of the interpreter's internal caches, the + result can vary from call to call; you may have to call + :func:`_clear_type_cache()` to get more predictable results. + + .. versionadded:: 3.4 + + .. impl-detail:: + Not all Python implementations may be able to return this information. + + .. function:: getcheckinterval() Return the interpreter's "check interval"; see :func:`setcheckinterval`. diff --git a/Include/objimpl.h b/Include/objimpl.h index 3d5f5094048..63465009e3a 100644 --- a/Include/objimpl.h +++ b/Include/objimpl.h @@ -98,6 +98,8 @@ PyAPI_FUNC(void *) PyObject_Malloc(size_t); PyAPI_FUNC(void *) PyObject_Realloc(void *, size_t); PyAPI_FUNC(void) PyObject_Free(void *); +/* This function returns the number of allocated memory blocks, regardless of size */ +PyAPI_FUNC(Py_ssize_t) _Py_GetAllocatedBlocks(void); /* Macros */ #ifdef WITH_PYMALLOC diff --git a/Lib/test/regrtest.py b/Lib/test/regrtest.py index 892ff6b443f..5d9d82d6735 100755 --- a/Lib/test/regrtest.py +++ b/Lib/test/regrtest.py @@ -615,7 +615,7 @@ def main(tests=None, testdir=None, verbose=0, quiet=False, sys.exit(2) from queue import Queue from subprocess import Popen, PIPE - debug_output_pat = re.compile(r"\[\d+ refs\]$") + debug_output_pat = re.compile(r"\[\d+ refs, \d+ blocks\]$") output = Queue() pending = MultiprocessTests(tests) opt_args = support.args_from_interpreter_flags() @@ -1320,33 +1320,50 @@ def dash_R(the_module, test, indirect_test, huntrleaks): del sys.modules[the_module.__name__] exec('import ' + the_module.__name__) - deltas = [] nwarmup, ntracked, fname = huntrleaks fname = os.path.join(support.SAVEDCWD, fname) repcount = nwarmup + ntracked + rc_deltas = [0] * repcount + alloc_deltas = [0] * repcount + print("beginning", repcount, "repetitions", file=sys.stderr) print(("1234567890"*(repcount//10 + 1))[:repcount], file=sys.stderr) sys.stderr.flush() - dash_R_cleanup(fs, ps, pic, zdc, abcs) for i in range(repcount): - rc_before = sys.gettotalrefcount() run_the_test() + alloc_after, rc_after = dash_R_cleanup(fs, ps, pic, zdc, abcs) sys.stderr.write('.') sys.stderr.flush() - dash_R_cleanup(fs, ps, pic, zdc, abcs) - rc_after = sys.gettotalrefcount() if i >= nwarmup: - deltas.append(rc_after - rc_before) + rc_deltas[i] = rc_after - rc_before + alloc_deltas[i] = alloc_after - alloc_before + alloc_before, rc_before = alloc_after, rc_after print(file=sys.stderr) - if any(deltas): - msg = '%s leaked %s references, sum=%s' % (test, deltas, sum(deltas)) - print(msg, file=sys.stderr) - sys.stderr.flush() - with open(fname, "a") as refrep: - print(msg, file=refrep) - refrep.flush() - return True - return False + # These checkers return False on success, True on failure + def check_rc_deltas(deltas): + return any(deltas) + def check_alloc_deltas(deltas): + # At least 1/3rd of 0s + if 3 * deltas.count(0) < len(deltas): + return True + # Nothing else than 1s, 0s and -1s + if not set(deltas) <= {1,0,-1}: + return True + return False + failed = False + for deltas, item_name, checker in [ + (rc_deltas, 'references', check_rc_deltas), + (alloc_deltas, 'memory blocks', check_alloc_deltas)]: + if checker(deltas): + msg = '%s leaked %s %s, sum=%s' % ( + test, deltas[nwarmup:], item_name, sum(deltas)) + print(msg, file=sys.stderr) + sys.stderr.flush() + with open(fname, "a") as refrep: + print(msg, file=refrep) + refrep.flush() + failed = True + return failed def dash_R_cleanup(fs, ps, pic, zdc, abcs): import gc, copyreg @@ -1412,8 +1429,11 @@ def dash_R_cleanup(fs, ps, pic, zdc, abcs): else: ctypes._reset_cache() - # Collect cyclic trash. + # Collect cyclic trash and read memory statistics immediately after. + func1 = sys.getallocatedblocks + func2 = sys.gettotalrefcount gc.collect() + return func1(), func2() def warm_caches(): # char cache diff --git a/Lib/test/support.py b/Lib/test/support.py index 4d639040f56..b98f2bf4236 100644 --- a/Lib/test/support.py +++ b/Lib/test/support.py @@ -1772,7 +1772,7 @@ def strip_python_stderr(stderr): This will typically be run on the result of the communicate() method of a subprocess.Popen object. """ - stderr = re.sub(br"\[\d+ refs\]\r?\n?", b"", stderr).strip() + stderr = re.sub(br"\[\d+ refs, \d+ blocks\]\r?\n?", b"", stderr).strip() return stderr def args_from_interpreter_flags(): diff --git a/Lib/test/test_sys.py b/Lib/test/test_sys.py index a1074c33d96..055592ba070 100644 --- a/Lib/test/test_sys.py +++ b/Lib/test/test_sys.py @@ -6,6 +6,7 @@ import textwrap import warnings import operator import codecs +import gc # count the number of test runs, used to create unique # strings to intern in test_intern() @@ -611,6 +612,29 @@ class SysModuleTest(unittest.TestCase): ret, out, err = assert_python_ok(*args) self.assertIn(b"free PyDictObjects", err) + @unittest.skipUnless(hasattr(sys, "getallocatedblocks"), + "sys.getallocatedblocks unavailable on this build") + def test_getallocatedblocks(self): + # Some sanity checks + a = sys.getallocatedblocks() + self.assertIs(type(a), int) + self.assertGreater(a, 0) + try: + # While we could imagine a Python session where the number of + # multiple buffer objects would exceed the sharing of references, + # it is unlikely to happen in a normal test run. + self.assertLess(a, sys.gettotalrefcount()) + except AttributeError: + # gettotalrefcount() not available + pass + gc.collect() + b = sys.getallocatedblocks() + self.assertLessEqual(b, a) + gc.collect() + c = sys.getallocatedblocks() + self.assertIn(c, range(b - 50, b + 50)) + + class SizeofTest(unittest.TestCase): def setUp(self): diff --git a/Misc/NEWS b/Misc/NEWS index f69c05caec2..c305f65293e 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -163,6 +163,9 @@ Core and Builtins Library ------- +- Issue #13390: New function :func:`sys.getallocatedblocks()` returns the + number of memory blocks currently allocated. + - Issue #16628: Fix a memory leak in ctypes.resize(). - Issue #13614: Fix setup.py register failure with invalid rst in description. @@ -433,6 +436,9 @@ Extension Modules Tests ----- +- Issue #13390: The ``-R`` option to regrtest now also checks for memory + allocation leaks, using :func:`sys.getallocatedblocks()`. + - Issue #16559: Add more tests for the json module, including some from the official test suite at json.org. Patch by Serhiy Storchaka. diff --git a/Objects/obmalloc.c b/Objects/obmalloc.c index 6225ebbbf13..c82c978e4da 100644 --- a/Objects/obmalloc.c +++ b/Objects/obmalloc.c @@ -525,6 +525,15 @@ static size_t ntimes_arena_allocated = 0; /* High water mark (max value ever seen) for narenas_currently_allocated. */ static size_t narenas_highwater = 0; +static Py_ssize_t _Py_AllocatedBlocks = 0; + +Py_ssize_t +_Py_GetAllocatedBlocks(void) +{ + return _Py_AllocatedBlocks; +} + + /* Allocate a new arena. If we run out of memory, return NULL. Else * allocate a new arena, and return the address of an arena_object * describing the new arena. It's expected that the caller will set @@ -785,6 +794,8 @@ PyObject_Malloc(size_t nbytes) if (nbytes > PY_SSIZE_T_MAX) return NULL; + _Py_AllocatedBlocks++; + /* * This implicitly redirects malloc(0). */ @@ -901,6 +912,7 @@ PyObject_Malloc(size_t nbytes) * and free list are already initialized. */ bp = pool->freeblock; + assert(bp != NULL); pool->freeblock = *(block **)bp; UNLOCK(); return (void *)bp; @@ -958,7 +970,12 @@ redirect: */ if (nbytes == 0) nbytes = 1; - return (void *)malloc(nbytes); + { + void *result = malloc(nbytes); + if (!result) + _Py_AllocatedBlocks--; + return result; + } } /* free */ @@ -978,6 +995,8 @@ PyObject_Free(void *p) if (p == NULL) /* free(NULL) has no effect */ return; + _Py_AllocatedBlocks--; + #ifdef WITH_VALGRIND if (UNLIKELY(running_on_valgrind > 0)) goto redirect; diff --git a/Python/pythonrun.c b/Python/pythonrun.c index dd320175741..f0d8550773f 100644 --- a/Python/pythonrun.c +++ b/Python/pythonrun.c @@ -38,9 +38,10 @@ #ifndef Py_REF_DEBUG #define PRINT_TOTAL_REFS() #else /* Py_REF_DEBUG */ -#define PRINT_TOTAL_REFS() fprintf(stderr, \ - "[%" PY_FORMAT_SIZE_T "d refs]\n", \ - _Py_GetRefTotal()) +#define PRINT_TOTAL_REFS() fprintf(stderr, \ + "[%" PY_FORMAT_SIZE_T "d refs, " \ + "%" PY_FORMAT_SIZE_T "d blocks]\n", \ + _Py_GetRefTotal(), _Py_GetAllocatedBlocks()) #endif #ifdef __cplusplus diff --git a/Python/sysmodule.c b/Python/sysmodule.c index 92c5b676116..20792c243c2 100644 --- a/Python/sysmodule.c +++ b/Python/sysmodule.c @@ -894,6 +894,19 @@ one higher than you might expect, because it includes the (temporary)\n\ reference as an argument to getrefcount()." ); +static PyObject * +sys_getallocatedblocks(PyObject *self) +{ + return PyLong_FromSsize_t(_Py_GetAllocatedBlocks()); +} + +PyDoc_STRVAR(getallocatedblocks_doc, +"getallocatedblocks() -> integer\n\ +\n\ +Return the number of memory blocks currently allocated, regardless of their\n\ +size." +); + #ifdef COUNT_ALLOCS static PyObject * sys_getcounts(PyObject *self) @@ -1062,6 +1075,8 @@ static PyMethodDef sys_methods[] = { {"getdlopenflags", (PyCFunction)sys_getdlopenflags, METH_NOARGS, getdlopenflags_doc}, #endif + {"getallocatedblocks", (PyCFunction)sys_getallocatedblocks, METH_NOARGS, + getallocatedblocks_doc}, #ifdef COUNT_ALLOCS {"getcounts", (PyCFunction)sys_getcounts, METH_NOARGS}, #endif