Dec 22, 2025 · Dec 22, 2025
diff --git a/Include/internal/pycore_tracemalloc.h b/Include/internal/pycore_tracemalloc.h
    } initialized;

    /* Is tracemalloc tracing memory allocations?
       Variable protected by the TABLES_LOCK(). */
       Variable protected by the TABLES_LOCK() and stored atomically.
       Atomic store is used so that it can read without locking for the
       general case of checking if tracemalloc is enabled.
       */
    int tracing;

    /* limit of the number of frames in a traceback, 1 by default.
diff --git a/Misc/NEWS.d/next/Core_and_Builtins/2025-12-22-12-03-09.gh-issue-143057.Majsre.rst b/Misc/NEWS.d/next/Core_and_Builtins/2025-12-22-12-03-09.gh-issue-143057.Majsre.rst
 Avoid locking in :c:func:`PyTraceMalloc_Track` and :c:func:`PyTraceMalloc_Untrack` when :mod:`tracemalloc` is not enabled.
diff --git a/Python/tracemalloc.c b/Python/tracemalloc.c

    /* everything is ready: start tracing Python memory allocations */
    TABLES_LOCK();
    tracemalloc_config.tracing = 1;
 _Py_atomic_store_int_relaxed(&tracemalloc_config.tracing, 1);
    TABLES_UNLOCK();

    return 0;
    }

    /* stop tracing Python memory allocations */
    tracemalloc_config.tracing = 0;
 _Py_atomic_store_int_relaxed(&tracemalloc_config.tracing, 0);

    /* unregister the hook on memory allocators */
    PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &allocators.raw);
 PyTraceMalloc_Track(unsigned int domain, uintptr_t ptr,
                    size_t size)
 {
    if (_Py_atomic_load_int_relaxed(&tracemalloc_config.tracing) == 0) {
        /* tracemalloc is not tracing: do nothing */
        return -2;
    }
    PyGILState_STATE gil_state = PyGILState_Ensure();
    TABLES_LOCK();

 int
 PyTraceMalloc_Untrack(unsigned int domain, uintptr_t ptr)
 {
    if (_Py_atomic_load_int_relaxed(&tracemalloc_config.tracing) == 0) {
        /* tracemalloc is not tracing: do nothing */
        return -2;
    }

    TABLES_LOCK();

    int result;
Original file line number	Diff line number	Diff line change
Expand Up		@@ -21,7 +21,10 @@ struct _PyTraceMalloc_Config {
		} initialized;

		/* Is tracemalloc tracing memory allocations?
		Variable protected by the TABLES_LOCK(). */
		Variable protected by the TABLES_LOCK() and stored atomically.
		Atomic store is used so that it can read without locking for the
		general case of checking if tracemalloc is enabled.
		*/
		int tracing;

		/* limit of the number of frames in a traceback, 1 by default.
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Original file line number	Diff line number	Diff line change
		@@ -0,0 +1 @@
		Avoid locking in :c:func:`PyTraceMalloc_Track` and :c:func:`PyTraceMalloc_Untrack` when :mod:`tracemalloc` is not enabled.
Original file line number	Diff line number	Diff line change
Expand Up		@@ -840,7 +840,7 @@ _PyTraceMalloc_Start(int max_nframe)

		/* everything is ready: start tracing Python memory allocations */
		TABLES_LOCK();
		tracemalloc_config.tracing = 1;
		_Py_atomic_store_int_relaxed(&tracemalloc_config.tracing, 1);
		TABLES_UNLOCK();

		return 0;
Expand All		@@ -857,7 +857,7 @@ _PyTraceMalloc_Stop(void)
		}

		/* stop tracing Python memory allocations */
		tracemalloc_config.tracing = 0;
		_Py_atomic_store_int_relaxed(&tracemalloc_config.tracing, 0);

		/* unregister the hook on memory allocators */
		PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &allocators.raw);
Expand DownExpand Up		@@ -1197,6 +1197,10 @@ int
		PyTraceMalloc_Track(unsigned int domain, uintptr_t ptr,
		size_t size)
		{
		if (_Py_atomic_load_int_relaxed(&tracemalloc_config.tracing) == 0) {
		/* tracemalloc is not tracing: do nothing */
		return -2;
		}
		PyGILState_STATE gil_state = PyGILState_Ensure();
		TABLES_LOCK();

Expand All		@@ -1218,6 +1222,11 @@ PyTraceMalloc_Track(unsigned int domain, uintptr_t ptr,
		int
		PyTraceMalloc_Untrack(unsigned int domain, uintptr_t ptr)
		{
		if (_Py_atomic_load_int_relaxed(&tracemalloc_config.tracing) == 0) {
		/* tracemalloc is not tracing: do nothing */
		return -2;
		}

		TABLES_LOCK();

		int result;
Expand Down