lua54/luabugs7.patch

From a1f77a234a053da46b06d5d4be00ffb30d3eb45b Mon Sep 17 00:00:00 2001
From: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Tue, 23 Aug 2022 16:06:23 -0300
Subject: [PATCH] Bug: set correct pause when (re)entering gen. collection.

---
 lgc.c | 63 +++++++++++++++++++++++++++++------------------------------
 1 file changed, 31 insertions(+), 32 deletions(-)

diff --git a/lgc.c b/lgc.c
index 42a73d813..317ea4508 100644
--- a/src/lgc.c
+++ b/src/lgc.c
@@ -1041,7 +1041,25 @@ void luaC_checkfinalizer (lua_State *L, GCObject *o, Table *mt) {
 ** =======================================================
 */
 
-static void setpause (global_State *g);
+
+/*
+** Set the "time" to wait before starting a new GC cycle; cycle will
+** start when memory use hits the threshold of ('estimate' * pause /
+** PAUSEADJ). (Division by 'estimate' should be OK: it cannot be zero,
+** because Lua cannot even start with less than PAUSEADJ bytes).
+*/
+static void setpause (global_State *g) {
+  l_mem threshold, debt;
+  int pause = getgcparam(g->gcpause);
+  l_mem estimate = g->GCestimate / PAUSEADJ;  /* adjust 'estimate' */
+  lua_assert(estimate > 0);
+  threshold = (pause < MAX_LMEM / estimate)  /* overflow? */
+            ? estimate * pause  /* no overflow */
+            : MAX_LMEM;  /* overflow; truncate to maximum */
+  debt = gettotalbytes(g) - threshold;
+  if (debt > 0) debt = 0;
+  luaE_setdebt(g, debt);
+}
 
 
 /*
@@ -1285,6 +1303,15 @@ static void atomic2gen (lua_State *L, global_State *g) {
 }
 
 
+/*
+** Set debt for the next minor collection, which will happen when
+** memory grows 'genminormul'%.
+*/
+static void setminordebt (global_State *g) {
+  luaE_setdebt(g, -(cast(l_mem, (gettotalbytes(g) / 100)) * g->genminormul));
+}
+
+
 /*
 ** Enter generational mode. Must go until the end of an atomic cycle
 ** to ensure that all objects are correctly marked and weak tables
@@ -1297,6 +1324,7 @@ static lu_mem entergen (lua_State *L, global_State *g) {
   luaC_runtilstate(L, bitmask(GCSpropagate));  /* start new cycle */
   numobjs = atomic(L);  /* propagates all and then do the atomic stuff */
   atomic2gen(L, g);
+  setminordebt(g);  /* set debt assuming next cycle will be minor */
   return numobjs;
 }
 
@@ -1342,15 +1370,6 @@ static lu_mem fullgen (lua_State *L, global_State *g) {
 }
 
 
-/*
-** Set debt for the next minor collection, which will happen when
-** memory grows 'genminormul'%.
-*/
-static void setminordebt (global_State *g) {
-  luaE_setdebt(g, -(cast(l_mem, (gettotalbytes(g) / 100)) * g->genminormul));
-}
-
-
 /*
 ** Does a major collection after last collection was a "bad collection".
 **
@@ -1422,8 +1441,8 @@ static void genstep (lua_State *L, global_State *g) {
       lu_mem numobjs = fullgen(L, g);  /* do a major collection */
       if (gettotalbytes(g) < majorbase + (majorinc / 2)) {
         /* collected at least half of memory growth since last major
-           collection; keep doing minor collections */
-        setminordebt(g);
+           collection; keep doing minor collections. */
+        lua_assert(g->lastatomic == 0);
       }
       else {  /* bad collection */
         g->lastatomic = numobjs;  /* signal that last collection was bad */
@@ -1449,26 +1468,6 @@ static void genstep (lua_State *L, global_State *g) {
 */
 
 
-/*
-** Set the "time" to wait before starting a new GC cycle; cycle will
-** start when memory use hits the threshold of ('estimate' * pause /
-** PAUSEADJ). (Division by 'estimate' should be OK: it cannot be zero,
-** because Lua cannot even start with less than PAUSEADJ bytes).
-*/
-static void setpause (global_State *g) {
-  l_mem threshold, debt;
-  int pause = getgcparam(g->gcpause);
-  l_mem estimate = g->GCestimate / PAUSEADJ;  /* adjust 'estimate' */
-  lua_assert(estimate > 0);
-  threshold = (pause < MAX_LMEM / estimate)  /* overflow? */
-            ? estimate * pause  /* no overflow */
-            : MAX_LMEM;  /* overflow; truncate to maximum */
-  debt = gettotalbytes(g) - threshold;
-  if (debt > 0) debt = 0;
-  luaE_setdebt(g, debt);
-}
-
-
 /*
 ** Enter first sweep phase.
 ** The call to 'sweeptolive' makes the pointer point to an object