Merge branch 'maint'

* maint:
  Fix tracing of processes executing dirty
  Perform check_process_code while process is executing dirty
  Fix purge of code
  Reclaim literal area after purge has completed
  Separate literal area from code

Conflicts:
	erts/emulator/beam/global.h

2 files changed, 23 insertions, 12 deletions

diff --git a/erts/doc/src/erl_nif.xml b/erts/doc/src/erl_nif.xml
index 2b627281fe..4ec5ab78d8 100644
--- a/erts/doc/src/erl_nif.xml
+++ b/erts/doc/src/erl_nif.xml
@@ -488,18 +488,6 @@ return term;</code>
               sending process is not alive. Deallocation of certain internal
               resources, such as process heap and process control block, is
               delayed until the dirty NIF has completed.</p>
-            <p>Known issue that are planned to be fixed:</p>
-            <list type="bulleted">
-              <item>
-                <p>As purging of a module might need to garbage
-                  collect a process to determine if it has
-                  references to the module, a process executing a dirty
-                  NIF can delay purging for a very long time. Delaying
-                  a purge operation implies delaying <em>all</em> code
-                  loading operations, which can cause severe problems for
-                  the system as a whole.</p>
-              </item>
-            </list>
           </item>
         </taglist>
       </item>
diff --git a/erts/doc/src/erlang.xml b/erts/doc/src/erlang.xml
index 2b7a3b85e5..51ebddc155 100644
--- a/erts/doc/src/erlang.xml
+++ b/erts/doc/src/erlang.xml
@@ -776,6 +776,29 @@ Z = erlang:adler32_combine(X,Y,iolist_size(Data2)).</code>
             by passing option <c>{allow_gc, false}</c>.</p>
           </item>
         </taglist>
+	<note>
+	<p>
+	  Up until ERTS version 8.*, the check process code operation
+	  checks for all types of references to the old code. That is,
+	  direct references (e.g. return addresses on the process
+	  stack), indirect references (<c>fun</c>s in process
+	  context), and references to literals in the code.
+	</p>
+	<p>
+	  As of ERTS version 9.0, the check process code operation
+	  only checks for direct references to the code. Indirect
+	  references via <c>fun</c>s will be ignored. If such
+	  <c>fun</c>s exist and are used after a purge of the old
+	  code, an exception will be raised upon usage (same as
+	  the case when the <c>fun</c> is received by the process
+	  after the purge). Literals will be taken care of (copied)
+	  at a  later stage. This behavior can as of ERTS version
+	  8.1 be enabled when
+	  <seealso marker="doc/installation_guide:INSTALL#Advanced-configuration-and-build-of-ErlangOTP_Configuring">building OTP</seealso>,
+	  and will automatically be enabled if dirty scheduler
+	  support is enabled.
+	</p>
+	</note>
         <p>See also <seealso marker="kernel:code">
           <c>kernel:code(3)</c></seealso>.</p>
         <p>Failures:</p>