X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=snapshot.cc;h=24e8d073ca1330eb778b897955e500dab30f9c5e;hb=0d3c4eca7d657d93c5a30681f22d9856847370f9;hp=dab1a480d5910d84ed97ec2782e6fa73d7e50a85;hpb=db26d1e3370a583f8eef79194c87ba9d2ef92530;p=c11tester.git

diff --git a/snapshot.cc b/snapshot.cc
index dab1a480..24e8d073 100644
--- a/snapshot.cc
+++ b/snapshot.cc
@@ -14,6 +14,9 @@
 #include "context.h"
 #include "model.h"
 
+
+#if USE_MPROTECT_SNAPSHOT
+
 /** PageAlignedAdressUpdate return a page aligned address for the
  * address being added as a side effect the numBytes are also changed.
  */
@@ -22,8 +25,6 @@ static void * PageAlignAddressUpward(void *addr)
 	return (void *)((((uintptr_t)addr) + PAGESIZE - 1) & ~(PAGESIZE - 1));
 }
 
-#if USE_MPROTECT_SNAPSHOT
-
 /* Each SnapShotRecord lists the firstbackingpage that must be written to
  * revert to that snapshot */
 struct SnapShotRecord {
@@ -277,20 +278,14 @@ struct fork_snapshotter {
 	 */
 	volatile snapshot_id mIDToRollback;
 
-	/**
-	 * @brief The context for the shared (non-snapshot) stack
-	 *
-	 * This context is passed between the various processes which represent
-	 * various snapshot states. It should be used primarily for the
-	 * "client-side" code, not the main snapshot loop.
-	 */
-	ucontext_t shared_ctxt;
+
 
 	/** @brief Inter-process tracking of the next snapshot ID */
 	snapshot_id currSnapShotID;
 };
 
 static struct fork_snapshotter *fork_snap = NULL;
+ucontext_t shared_ctxt;
 
 /** @statics
  *   These variables are necessary because the stack is shared region and
@@ -381,7 +376,7 @@ static void fork_loop() {
 	/* switch back here when takesnapshot is called */
 	snapshotid = fork_snap->currSnapShotID;
 	if (model->params.nofork) {
-		setcontext(&fork_snap->shared_ctxt);
+		setcontext(&shared_ctxt);
 		_Exit(EXIT_SUCCESS);
 	}
 
@@ -394,7 +389,7 @@ static void fork_loop() {
 		modellock = 0;
 
 		if (0 == forkedID) {
-			setcontext(&fork_snap->shared_ctxt);
+			setcontext(&shared_ctxt);
 		} else {
 			DEBUG("parent PID: %d, child PID: %d, snapshot ID: %d\n",
 						getpid(), forkedID, snapshotid);
@@ -415,8 +410,8 @@ static void fork_loop() {
 
 static void fork_startExecution(ucontext_t *context, VoidFuncPtr entryPoint) {
 	/* setup an "exiting" context */
-	char stack[128];
-	create_context(&exit_ctxt, stack, sizeof(stack), fork_exit);
+	int exit_stack_size = 256;
+	create_context(&exit_ctxt, snapshot_calloc(exit_stack_size, 1), exit_stack_size, fork_exit);
 
 	/* setup the system context */
 	create_context(context, fork_snap->mStackBase, STACK_SIZE_DEFAULT, entryPoint);
@@ -425,7 +420,7 @@ static void fork_startExecution(ucontext_t *context, VoidFuncPtr entryPoint) {
 }
 
 static snapshot_id fork_take_snapshot() {
-	model_swapcontext(&fork_snap->shared_ctxt, &private_ctxt);
+	model_swapcontext(&shared_ctxt, &private_ctxt);
 	DEBUG("TAKESNAPSHOT RETURN\n");
 	return snapshotid;
 }
@@ -434,7 +429,7 @@ static void fork_roll_back(snapshot_id theID)
 {
 	DEBUG("Rollback\n");
 	fork_snap->mIDToRollback = theID;
-	model_swapcontext(&fork_snap->shared_ctxt, &exit_ctxt);
+	model_swapcontext(model->get_system_context(), &exit_ctxt);
 	fork_snap->mIDToRollback = -1;
 }