Rework fatal error chapter

Update #2811.

c-user/fatal_error.rst

@@ -13,34 +13,40 @@ Introduction
 ============
 
 The fatal error manager processes all fatal or irrecoverable errors and other
-sources of system termination (for example after ``exit()``).  The directives
+sources of system termination (for example after :c:func:`exit()`).  Fatal
+errors are identified by the (fatal source, error code) pair.  The directives
 provided by the fatal error manager are:
 
-- rtems_fatal_error_occurred_ - Invoke the fatal error handler
+- rtems_fatal_ - Invoke the fatal error handler
-
-- rtems_fatal_ - Invoke the fatal error handler with error source
 
 - rtems_exception_frame_print_ - Print the CPU exception frame
 
-- rtems_fatal_source_text_ - Return the falet source text
+- rtems_fatal_source_text_ - Return the fatal source text
 
 - rtems_internal_error_text_ - Return the error code text
 
+- rtems_fatal_error_occurred_ - Invoke the fatal error handler (deprecated)
+
 Background
 ==========
+
+Overview
+--------
+
 .. index:: fatal error detection
 .. index:: fatal error processing
 .. index:: fatal error user extension
 
 The fatal error manager is called upon detection of an irrecoverable error
-condition by either RTEMS or the application software.  Fatal errors can be
+condition by either RTEMS or the application software.  Fatal errors are also
-detected from three sources:
+used in case it is difficult or impossible to return an error condition by
+other means, e.g. a return value of a directive call.  Fatal errors can be
+detected from various sources, for example
 
-- the executive (RTEMS)
+- the executive (RTEMS),
-
+- support libraries,
-- user system code
+- user system code, and
-
+- user application code.
-- user application code
 
 RTEMS automatically invokes the fatal error manager upon detection of an error
 it considers to be fatal.  Similarly, the user should invoke the fatal error
@@ -50,10 +56,11 @@ Each static or dynamic user extension set may include a fatal error handler.
 The fatal error handler in the static extension set can be used to provide
 access to debuggers and monitors which may be present on the target hardware.
 If any user-supplied fatal error handlers are installed, the fatal error
-manager will invoke them.  If no user handlers are configured or if all the
+manager will invoke them.  Usually, the board support package provides a fatal
-user handler return control to the fatal error manager, then the RTEMS default
+error extesion which resets the board.  If no user handlers are configured or
-fatal error handler is invoked.  If the default fatal error handler is invoked,
+if all the user handler return control to the fatal error manager, then the
-then the system state is marked as failed.
+RTEMS default fatal error handler is invoked.  If the default fatal error
+handler is invoked, then the system state is marked as failed.
 
 Although the precise behavior of the default fatal error handler is processor
 specific, in general, it will disable all maskable interrupts, place the error
@@ -62,6 +69,174 @@ a register), and halt the processor.  The precise actions of the RTEMS fatal
 error are discussed in the Default Fatal Error Processing chapter of the
 Applications Supplement document for a specific target processor.
 
+Fatal Sources
+-------------
+
+The following fatal sources are defined for RTEMS via the
+:c:type:`rtems_fatal_source` enumeration.
+
+INTERNAL_ERROR_CORE
+    Errors of the core operating system.  See :ref:`internal_errors`.
+
+INTERNAL_ERROR_RTEMS_API
+    Errors of the Classic API.
+
+INTERNAL_ERROR_POSIX_API
+    Errors of the POSIX API.
+
+RTEMS_FATAL_SOURCE_BDBUF
+    Fatal source for the block device cache.  See
+    :c:type:`rtems_bdbuf_fatal_code`.
+
+RTEMS_FATAL_SOURCE_APPLICATION
+    Fatal source for application-specific errors.  The fatal code is
+    application-specific.
+
+RTEMS_FATAL_SOURCE_EXIT
+    Fatal source of :c:func:`exit()`.  The fatal code is the :c:func:`exit()`
+    status code.
+
+RTEMS_FATAL_SOURCE_BSP
+    Fatal source for BSP errors.  The fatal codes are defined in
+    :file:`<bsp/fatal.h>`.  Examples are interrupt and exception
+    initialization.  See :c:type:`bsp_fatal_code` and :c:func:`bsp_fatal()`.
+
+RTEMS_FATAL_SOURCE_ASSERT
+    Fatal source of :c:macro:`assert()`.  The fatal code is the pointer value
+    of the assert context.  See :c:type:`rtems_assert_context`.
+
+RTEMS_FATAL_SOURCE_STACK_CHECKER
+    Fatal source of the stack checker.  The fatal code is the object name of
+    the executing task.
+
+RTEMS_FATAL_SOURCE_EXCEPTION
+    Fatal source of the exceptions.  The fatal code is the pointer value of the
+    exception frame pointer.  See :c:type:`rtems_exception_frame` and
+    :ref:`rtems_exception_frame_print`.
+
+RTEMS_FATAL_SOURCE_SMP
+    Fatal source of SMP domain.  See :c:type:`SMP_Fatal_code`.
+
+.. _internal_errors:
+
+Internal Error Codes
+--------------------
+
+The following error codes are defined for the :c:data:`INTERNAL_ERROR_CORE`
+fatal source.
+
+INTERNAL_ERROR_NO_CONFIGURATION_TABLE
+  Document me.
+
+INTERNAL_ERROR_NO_CPU_TABLE
+  Document me.
+
+INTERNAL_ERROR_TOO_LITTLE_WORKSPACE
+    Document me.
+
+INTERNAL_ERROR_WORKSPACE_ALLOCATION
+    Document me.
+
+INTERNAL_ERROR_INTERRUPT_STACK_TOO_SMALL
+    Document me.
+
+INTERNAL_ERROR_THREAD_EXITTED
+    Document me.
+
+INTERNAL_ERROR_INCONSISTENT_MP_INFORMATION
+    Document me.
+
+INTERNAL_ERROR_INVALID_NODE
+    Document me.
+
+INTERNAL_ERROR_NO_MPCI
+    Document me.
+
+INTERNAL_ERROR_BAD_PACKET
+    Document me.
+
+INTERNAL_ERROR_OUT_OF_PACKETS
+    Document me.
+
+INTERNAL_ERROR_OUT_OF_GLOBAL_OBJECTS
+    Document me.
+
+INTERNAL_ERROR_OUT_OF_PROXIES
+    Document me.
+
+INTERNAL_ERROR_INVALID_GLOBAL_ID
+    Document me.
+
+INTERNAL_ERROR_BAD_STACK_HOOK
+    Document me.
+
+INTERNAL_ERROR_BAD_ATTRIBUTES
+    Document me.
+
+INTERNAL_ERROR_IMPLEMENTATION_KEY_CREATE_INCONSISTENCY
+    Document me.
+
+INTERNAL_ERROR_THREAD_QUEUE_ENQUEUE_FROM_BAD_STATE
+    Document me.
+
+INTERNAL_ERROR_UNLIMITED_AND_MAXIMUM_IS_0
+    Document me.
+
+INTERNAL_ERROR_GXX_KEY_ADD_FAILED
+    Document me.
+
+INTERNAL_ERROR_GXX_MUTEX_INIT_FAILED
+    Document me.
+
+INTERNAL_ERROR_NO_MEMORY_FOR_HEAP
+    Document me.
+
+INTERNAL_ERROR_CPU_ISR_INSTALL_VECTOR
+    Document me.
+
+INTERNAL_ERROR_RESOURCE_IN_USE
+    Document me.
+
+INTERNAL_ERROR_RTEMS_INIT_TASK_ENTRY_IS_NULL
+    Document me.
+
+INTERNAL_ERROR_POSIX_INIT_THREAD_ENTRY_IS_NULL
+    Document me.
+
+INTERNAL_ERROR_THREAD_QUEUE_DEADLOCK
+    Document me.
+
+INTERNAL_ERROR_THREAD_QUEUE_ENQUEUE_STICKY_FROM_BAD_STATE
+    Document me.
+
+INTERNAL_ERROR_BAD_THREAD_DISPATCH_DISABLE_LEVEL
+    Document me.
+
+INTERNAL_ERROR_BAD_THREAD_DISPATCH_ENVIRONMENT
+    On SMP configurations, it is a fatal error to call blocking operating
+    system with interrupts disabled, since this prevents delivery of
+    inter-processor interrupts.  This could lead to executing threads which are
+    not allowed to execute resulting in undefined system behaviour.
+
+    Some CPU ports, for example the ARM Cortex-M port, have a similar problem,
+    since the interrupt state is not a part of the thread context.
+
+    This fatal error is detected in the operating system core function
+    :c:func:`_Thread_Do_dispatch()` responsible to carry out a thread dispatch.
+
+    An example code to provoke this fatal error is:
+
+    .. code-block:: c
+
+        void bad(void)
+        {
+          rtems_interrupt_level level;
+
+          rtems_interrupt_local_disable(level);
+          rtems_task_suspend(RTEMS_SELF);
+          rtems_interrupt_local_enable(level);
+        }
+
 Operations
 ==========
 
@@ -69,40 +244,45 @@ Operations
 
 Announcing a Fatal Error
 ------------------------
-.. index:: _Internal_errors_What_happened
+.. index:: _Terminate
 
-The ``rtems_fatal_error_occurred`` directive is invoked when a fatal error is
+The :c:func:`_Terminate()` internal error handler is invoked when the
-detected.  Before invoking any user-supplied fatal error handlers or the RTEMS
+application or the executive itself determines that a fatal error has occurred
-fatal error handler, the ``rtems_fatal_error_occurred`` directive stores useful
+or a final system state is reached (for example after :c:func:`rtems_fatal()`
-information in the variable ``_Internal_errors_What_happened``.  This structure
+or :c:func:`exit()`).
-contains three pieces of information:
 
-- the source of the error (API or executive core),
+The first action of the internal error handler is to call the fatal handler of
+the user extensions.  For the initial extensions the following conditions are
+required
 
-- whether the error was generated internally by the executive, and a
+- a valid stack pointer and enough stack space,
 
-- a numeric code to indicate the error type.
+- a valid code memory, and
 
-The error type indicator is dependent on the source of the error and whether or
+- valid read-only data.
-not the error was internally generated by the executive.  If the error was
-generated from an API, then the error code will be of that API's error or
-status codes.  The status codes for the RTEMS API are in
-cpukit/rtems/include/rtems/rtems/status.h.  Those for the POSIX API can be
-found in <errno.h>.
 
-The ``rtems_fatal_error_occurred`` directive is responsible for invoking an
+For the initial extensions the read-write data (including .bss segment) is not
-optional user-supplied fatal error handler and/or the RTEMS fatal error
+required on single processor configurations.  On SMP configurations, however,
-handler.  All fatal error handlers are passed an error code to describe the
+the read-write data must be initialized since this function must determine the
-error detected.
+state of the other processors and request them to shut-down if necessary.
 
-Occasionally, an application requires more sophisticated fatal error processing
+Non-initial extensions require in addition valid read-write data.  The board
-such as passing control to a debugger.  For these cases, a user-supplied fatal
+support package (BSP) may install an initial extension that performs a system
-error handler can be specified in the RTEMS configuration table.  The User
+reset.  In this case the non-initial extensions will be not called.
-Extension Table field fatal contains the address of the fatal error handler to
+
-be executed when the ``rtems_fatal_error_occurred`` directive is called.  If
+The fatal handler are called with three parameters:
-the field is set to NULL or if the configured fatal error handler returns to
+
-the executive, then the default handler provided by RTEMS is executed.  This
+- the fatal source,
-default handler will halt execution on the processor where the error occurred.
+
+- a legacy parameter, the internal error indicator, and
+
+- an error code with a fatal source dependent content.
+
+Once all fatal handler executed, the error information will be stored to
+:c:data:`_Internal_errors_What_happened` and the system state is set to
+:c:macro:`SYSTEM_STATE_TERMINATED`.
+
+The final step is to call the CPU port specific :c:func:`_CPU_Fatal_halt()`.
 
 Directives
 ==========
@@ -111,53 +291,14 @@ This section details the fatal error manager's directives.  A subsection is
 dedicated to each of this manager's directives and describes the calling
 sequence, related constants, usage, and status codes.
 
-.. raw:: latex
-
-   \clearpage
-
-.. _rtems_fatal_error_occurred:
-
-FATAL_ERROR_OCCURRED - Invoke the fatal error handler
------------------------------------------------------
-.. index:: announce fatal error
-.. index:: fatal error, announce
-.. index:: rtems_fatal_error_occurred
-
-CALLING SEQUENCE:
-    .. code-block:: c
-
-        void rtems_fatal_error_occurred(
-            uint32_t  the_error
-        );
-
-DIRECTIVE STATUS CODES:
-    NONE
-
-DESCRIPTION:
-    This directive processes fatal errors.  If the FATAL error extension is
-    defined in the configuration table, then the user-defined error extension
-    is called.  If configured and the provided FATAL error extension returns,
-    then the RTEMS default error handler is invoked.  This directive can be
-    invoked by RTEMS or by the user's application code including initialization
-    tasks, other tasks, and ISRs.
-
-NOTES:
-    This directive supports local operations only.
-
-    Unless the user-defined error extension takes special actions such as
-    restarting the calling task, this directive WILL NOT RETURN to the caller.
-
-    The user-defined extension for this directive may wish to initiate a global
-    shutdown.
-
 .. raw:: latex
 
    \clearpage
 
 .. _rtems_fatal:
 
-FATAL - Invoke the fatal error handler with error source
+FATAL - Invoke the fatal error
---------------------------------------------------------
+------------------------------
 .. index:: announce fatal error
 .. index:: fatal error, announce
 .. index:: rtems_fatal
@@ -168,14 +309,14 @@ CALLING SEQUENCE:
         void rtems_fatal(
            rtems_fatal_source source,
            rtems_fatal_code   error
-        );
+        ) RTEMS_NO_RETURN;
 
 DIRECTIVE STATUS CODES:
-    NONE
+    NONE - This function will not return to the caller.
 
 DESCRIPTION:
     This directive invokes the internal error handler with is internal set to
-    false.  See also ``rtems_fatal_error_occurred``.
+    false.
 
 .. raw:: latex
 
@@ -250,3 +391,44 @@ DIRECTIVE STATUS CODES:
 DESCRIPTION:
     Returns a text for an internal error code.  The text for each internal
     error code is the enumerator constant.
+
+.. raw:: latex
+
+   \clearpage
+
+.. _rtems_fatal_error_occurred:
+
+FATAL_ERROR_OCCURRED - Invoke the fatal error handler (deprecated)
+------------------------------------------------------------------
+.. index:: announce fatal error
+.. index:: fatal error, announce
+.. index:: rtems_fatal_error_occurred
+
+CALLING SEQUENCE:
+    .. code-block:: c
+
+        void rtems_fatal_error_occurred(
+            uint32_t  the_error
+        ) RTEMS_NO_RETURN;
+
+DIRECTIVE STATUS CODES:
+    NONE - This function will not return to the caller.
+
+DESCRIPTION:
+    This directive processes fatal errors.  If the FATAL error extension is
+    defined in the configuration table, then the user-defined error extension
+    is called.  If configured and the provided FATAL error extension returns,
+    then the RTEMS default error handler is invoked.  This directive can be
+    invoked by RTEMS or by the user's application code including initialization
+    tasks, other tasks, and ISRs.
+
+NOTES:
+    This directive is deprecated and should not be used in new code.
+
+    This directive supports local operations only.
+
+    Unless the user-defined error extension takes special actions such as
+    restarting the calling task, this directive WILL NOT RETURN to the caller.
+
+    The user-defined extension for this directive may wish to initiate a global
+    shutdown.