From: Alastair Bridgewater <lisphacker@users.sourceforge.net>
Date: Sat, 7 Aug 2010 13:45:45 +0000 (+0000)
Subject: 1.0.41.18: threads: stop_for_gc_handler should check for foriegn contexts
X-Git-Url: http://repo.macrolet.net/gitweb/?a=commitdiff_plain;h=c808a8c105050a5384c94418a8c80fafdfdc78c4;p=sbcl.git

1.0.41.18: threads: stop_for_gc_handler should check for foriegn contexts

  * stop_for_gc_handler() was unconditionally calling
fake_foreign_function_call(), even though a thread can legitimately
receive SIG_STOP_FOR_GC while in foreign code (and this is even the
normal situation when waiting for a mutex or waitqueue).

  * Use the now-idiomatic was_in_lisp variable fix: Check for an
active foreign-function call, only call fake_foreign_function_call
if the context is in lisp code, only undo the fake call if the
context was in lisp code.
---

diff --git a/src/runtime/interrupt.c b/src/runtime/interrupt.c
index 9a02e7f..0d426fa 100644
--- a/src/runtime/interrupt.c
+++ b/src/runtime/interrupt.c
@@ -1185,6 +1185,7 @@ void
 sig_stop_for_gc_handler(int signal, siginfo_t *info, os_context_t *context)
 {
     struct thread *thread=arch_os_get_current_thread();
+    boolean was_in_lisp;
 
     /* Test for GC_INHIBIT _first_, else we'd trap on every single
      * pseudo atomic until gc is finally allowed. */
@@ -1205,8 +1206,12 @@ sig_stop_for_gc_handler(int signal, siginfo_t *info, os_context_t *context)
 
     /* Not PA and GC not inhibited -- we can stop now. */
 
-    /* need the context stored so it can have registers scavenged */
-    fake_foreign_function_call(context);
+    was_in_lisp = !foreign_function_call_active_p(arch_os_get_current_thread());
+
+    if (was_in_lisp) {
+        /* need the context stored so it can have registers scavenged */
+        fake_foreign_function_call(context);
+    }
 
     /* Not pending anymore. */
     SetSymbolValue(GC_PENDING,NIL,thread);
@@ -1251,7 +1256,9 @@ sig_stop_for_gc_handler(int signal, siginfo_t *info, os_context_t *context)
              fixnum_value(thread_state(thread)));
     }
 
-    undo_fake_foreign_function_call(context);
+    if (was_in_lisp) {
+        undo_fake_foreign_function_call(context);
+    }
 }
 
 #endif
diff --git a/version.lisp-expr b/version.lisp-expr
index c3d9faf..d82c631 100644
--- a/version.lisp-expr
+++ b/version.lisp-expr
@@ -17,4 +17,4 @@
 ;;; checkins which aren't released. (And occasionally for internal
 ;;; versions, especially for internal versions off the main CVS
 ;;; branch, it gets hairier, e.g. "0.pre7.14.flaky4.13".)
-"1.0.41.17"
+"1.0.41.18"