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Concurrent Systems/notes/7- MUTEX-free concurrency.md

@@ -139,7 +139,7 @@ Idea: every operation is started by the invoking process and finalized by the ne
 This is needed for the so called ABA problem with compare&set:
 - A typical use of compare&set is
 ```
-	stmp <- X
+	tmp <- X
 	...
 	if X.compare&set(tmp, v) then ...
 ```
@@ -153,13 +153,14 @@ TOP : a register that can be read or compare&setted
 
 ```
 push(w) :=
-	while true do ⟨i,v,s⟩ <- TOP
-	conclude(i,v,s)
-	if i=k then
-		return FULL
-		newtop <- ⟨i+1,w,STACK[i+1].seq_num+1⟩
-		if TOP.compare&set(⟨i,v,s⟩,newtop) then
-			return OK
+	while true do
+		⟨i,v,s⟩ <- TOP
+		conclude(i,v,s)
+		if i=k then
+			return FULL
+			newtop <- ⟨i+1,w,STACK[i+1].seq_num+1⟩
+			if TOP.compare&set(⟨i,v,s⟩,newtop) then
+				return OK
 
 conclude(i, v, s) :=
 	tmp <- STACK[i].val