Place jump0 in wctx

We just want to initialize jump0 once per worker thread which we now achieve by placing jump0 in our worker context wctx. Previous to this, we would rerun the $PUSH every time we entered wt_work_cb, and thus actually push a new exception jump point to the stack - effectively a memory "leak" with run-away memory consumption as a consequence.
actonlang · Apr 5, 2024 · 2ed7582 · 2ed7582
1 parent c0044a4
commit 2ed7582
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Showing 2 changed files with 8 additions and 7 deletions.
diff --git a/base/rts/rts.c b/base/rts/rts.c
@@ -1500,7 +1500,6 @@ void wt_wake_cb(uv_async_t *ev) {
 void wt_work_cb(uv_check_t *ev) {
     WorkerCtx wctx = (WorkerCtx)pthread_getspecific(pkey_wctx);
     assert(wctx->id >= 0 && wctx->id < 256);
-    volatile JumpBuf jump0 = NULL;
 
     struct timespec ts_start, ts1, ts2, ts3;
     long long int runtime = 0;
@@ -1525,9 +1524,9 @@ void wt_work_cb(uv_check_t *ev) {
         wt_stats[wctx->id].state = WT_Working;
 
         $R r;
-        if (jump0 || $PUSH()) {                         // Normal path
-            if (!jump0) {
-                jump0 = wctx->jump_top;
+        if (wctx->jump0 || $PUSH()) {                         // Normal path
+            if (!wctx->jump0) {
+                wctx->jump0 = wctx->jump_top;
             }
             rtsd_printf("## Running actor %ld : %s", current->$globkey, current->$class->$GCINFO);
             r = cont->$class->__call__(cont, val);
@@ -1550,9 +1549,9 @@ void wt_work_cb(uv_check_t *ev) {
             else if (diff < (long long int)100 * 1000000000) { wt_stats[wctx->id].conts_100s++; }
             else                              { wt_stats[wctx->id].conts_inf++; }
         } else {                                        // Exceptional path
-            assert(jump0 != NULL);
-            assert(jump0->xval != NULL);
-            B_BaseException ex = jump0->xval;
+            assert(wctx->jump0 != NULL);
+            assert(wctx->jump0->xval != NULL);
+            B_BaseException ex = wctx->jump0->xval;
             rtsd_printf("## (%d) Actor %ld : %s longjmp exception: %s", wctx->id, current->$globkey, current->$class->$GCINFO, ex->$class->$GCINFO);
             r = $R_FAIL(ex);
         }
@@ -1704,6 +1703,7 @@ void *main_loop(void *idx) {
     wctx->id = (long)idx;
     wctx->uv_loop = uv_loops[wctx->id];
     wctx->jump_top = NULL;
+    wctx->jump0 = NULL;
     pthread_setspecific(pkey_wctx, (void *)wctx);
 
     char tname[11]; // Enough for "Worker XXX\0"

diff --git a/base/rts/rts.h b/base/rts/rts.h
@@ -231,6 +231,7 @@ struct WorkerCtx {
     long id;
     uv_loop_t *uv_loop;
     volatile JumpBuf jump_top;
+    volatile JumpBuf jump0;
 };
 
 JumpBuf $PUSH_BUF();