[RFA/doco] document support for Ravenscar profile

[Joel Brobecker <brobecker at adacore dot com>]

This announces the support for debugging Ada programs using
the Ravenscar Profile, as well as documents the new commands
introduced as part of this effort.

    http://www.sourceware.org/ml/gdb-patches/2010-09/msg00408.html

gdb/ChangeLog:

        * NEWS: Announce Ravenscar Profile support.

gdb/doc/ChangeLog:

        * gdb.texinfo (The Ravenscar Profile): New node.

OK to commit?

Thanks,
---
 gdb/NEWS            |    3 +++
 gdb/doc/gdb.texinfo |   35 +++++++++++++++++++++++++++++++++++
 2 files changed, 38 insertions(+), 0 deletions(-)

diff --git a/gdb/NEWS b/gdb/NEWS
index 01d2f46..c982caf 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -67,6 +67,9 @@
   ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
      and i686 LynxOS (version 5.x).
 
+* Ada task switching is now supported on sparc-elf targets when
+  debugging a program using the Ravenscar Profile.
+
 *** Changes in GDB 7.2
 
 * Shared library support for remote targets by default
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 07f9ad6..9cdd00e 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -12861,6 +12861,8 @@ to be difficult.
 * Stopping Before Main Program:: Debugging the program during elaboration.
 * Ada Tasks::                   Listing and setting breakpoints in tasks.
 * Ada Tasks and Core Files::    Tasking Support when Debugging Core Files
+* The Ravenscar Profile::       Tasking Support when using the Ravenscar
+                                   Profile
 * Ada Glitches::                Known peculiarities of Ada mode.
 @end menu
 
@@ -13411,6 +13413,39 @@ privileges, using the command @samp{"set write on"} (@pxref{Patching}).
 Under these circumstances, you should make a backup copy of the core
 file before inspecting it with @value{GDBN}.
 
+@node The Ravenscar Profile
+@subsubsection Tasking Support when using the Ravenscar Profile
+@cindex Ravenscar Profile
+
+The @dfn{Ravenscar Profile} is a subset of the Ada tasking features,
+specifically designed for systems with safety-critical real-time
+requirements. With GNAT, the activation of this profile requires
+the use of a specific Runtime.
+
+@table @code
+@kindex set ravenscar task-switching on
+@cindex enable task switching with program using Ravenscar Profile
+@item set ravenscar task-switching on
+Allows task switching when debugging a program that uses the Ravenscar
+Profile.  This is the default.
+
+@kindex set ravenscar task-switching off
+@cindex disable task switching with program using Ravenscar Profile
+@item set ravenscar task-switching off
+Turn off task switching when debugging a program that uses the Ravenscar
+Profile.  This is mostly intended to help disable the code that adds
+support for the Ravenscar Profile, in case a bug in either @value{GDBN}
+or in the Ravenscar runtime is preventing @value{GDBN} from working
+properly.  To be completely effective, this command should be run
+before the program is started.
+
+@kindex show ravenscar task-switching
+@item show ravenscar task-switching
+Show whether it is possible to switch from task to task in a program
+using the Ravenscar Profile.
+
+@end table
+
 @node Ada Glitches
 @subsubsection Known Peculiarities of Ada Mode
 @cindex Ada, problems
-- 
1.7.1