Attachment 926448 Details for Bug 1116957 – Path to GDB for gdb.command to optionally release GIL

[patch] Path to GDB for gdb.command to optionally release GIL

python_gil.patch (text/plain), 3.83 KB, created by Phil Muldoon on 2014-08-13 13:56:33 UTC

(hide)

Description:

Filename:

MIME Type:

Creator: Phil Muldoon

Created: 2014-08-13 13:56:33 UTC

Size: 3.83 KB

patch

obsolete

>diff --git a/gdb/doc/python.texi b/gdb/doc/python.texi
>index 4688783..afa458b 100644
>--- a/gdb/doc/python.texi
>+++ b/gdb/doc/python.texi
>@@ -230,6 +230,14 @@ returned as a string.  The default is @code{False}, in which case the
> return value is @code{None}.  If @var{to_string} is @code{True}, the
> @value{GDBN} virtual terminal will be temporarily set to unlimited width
> and height, and its pagination will be disabled; @pxref{Screen Size}.
>+
>+The @var{release_gil} flag specifies whether @value{GDBN} ought to
>+release the Python GIL before executing the command.  This is useful
>+in multi-threaded Python programs where by default the Python
>+interpreter will acquire the GIL and lock other threads from
>+executing.  After the command has completed executing in @value{GDBN}
>+the Python GIL is reacquired. This flag must be a boolean value.  If
>+omitted, it defaults to @code{False}.
> @end defun
> 
> @findex gdb.breakpoints
>diff --git a/gdb/python/python-internal.h b/gdb/python/python-internal.h
>index 6e7e600..8990a93 100644
>--- a/gdb/python/python-internal.h
>+++ b/gdb/python/python-internal.h
>@@ -141,6 +141,8 @@ typedef int Py_ssize_t;
> #define PyGILState_Release(ARG) ((void)(ARG))
> #define PyEval_InitThreads()
> #define PyThreadState_Swap(ARG) ((void)(ARG))
>+#define PyEval_SaveThread() ((void)(ARG))
>+#define PyEval_RestoreThread(ARG) ((void)(ARG))
> #define PyEval_ReleaseLock()
> #endif
> 
>diff --git a/gdb/python/python.c b/gdb/python/python.c
>index 40c4ec9..4c55be6 100644
>--- a/gdb/python/python.c
>+++ b/gdb/python/python.c
>@@ -617,14 +617,18 @@ execute_gdb_command (PyObject *self, PyObject *args, PyObject *kw)
> {
>   const char *arg;
>   PyObject *from_tty_obj = NULL, *to_string_obj = NULL;
>-  int from_tty, to_string;
>+  PyObject *release_gil_obj = NULL;
>+  int from_tty, to_string, release_gil;
>   volatile struct gdb_exception except;
>-  static char *keywords[] = {"command", "from_tty", "to_string", NULL };
>+  static char *keywords[] = {"command", "from_tty", "to_string",
>+			     "release_gil", NULL };
>   char *result = NULL;
>+  PyThreadState *state;
> 
>-  if (! PyArg_ParseTupleAndKeywords (args, kw, "s|O!O!", keywords, &arg,
>+  if (! PyArg_ParseTupleAndKeywords (args, kw, "s|O!O!O!", keywords, &arg,
> 				     &PyBool_Type, &from_tty_obj,
>-				     &PyBool_Type, &to_string_obj))
>+				     &PyBool_Type, &to_string_obj,
>+				     &PyBool_Type, &release_gil_obj))
>     return NULL;
> 
>   from_tty = 0;
>@@ -645,12 +649,28 @@ execute_gdb_command (PyObject *self, PyObject *args, PyObject *kw)
>       to_string = cmp;
>     }
> 
>+  release_gil = 0;
>+  if (release_gil_obj)
>+    {
>+      int cmp = PyObject_IsTrue (release_gil_obj);
>+      if (cmp < 0)
>+	return NULL;
>+      release_gil = cmp;
>+    }
>+
>   TRY_CATCH (except, RETURN_MASK_ALL)
>     {
>       /* Copy the argument text in case the command modifies it.  */
>       char *copy = xstrdup (arg);
>       struct cleanup *cleanup = make_cleanup (xfree, copy);
> 
>+      /* In the case of long running GDB commands, allow the user to
>+	 release the Python GIL acquired by Python.  Restore the GIL
>+	 after the command has completed before handing back to
>+	 Python.  */
>+      if (release_gil)
>+	state = PyEval_SaveThread();
>+
>       make_cleanup_restore_integer (&interpreter_async);
>       interpreter_async = 0;
> 
>@@ -663,9 +683,21 @@ execute_gdb_command (PyObject *self, PyObject *args, PyObject *kw)
> 	  execute_command (copy, from_tty);
> 	}
> 
>+      /* Reacquire the GIL if it was released earlier.  */
>+      if (release_gil)
>+	PyEval_RestoreThread (state);
>+
>       do_cleanups (cleanup);
>     }
>-  GDB_PY_HANDLE_EXCEPTION (except);
>+  if (except.reason < 0)
>+    {
>+      /* Reacquire the GIL if it was released earlier.  */
>+      if (release_gil)
>+	PyEval_RestoreThread (state);
>+
>+      gdbpy_convert_exception (except);
>+      return NULL;
>+    }
> 
>   /* Do any commands attached to breakpoint we stopped at.  */
>   bpstat_do_actions ();

Actions: View | Diff

Attachments on bug 1116957: 926448