bio: doFastMemoryTest should try to kill io threads as well.

(cherry picked from commit f86602339968cc89e31bd51fb9d6c771c3ab26ee)

src/debug.c

@@ -1530,6 +1530,7 @@ static void killMainThread(void) {
 static void killThreads(void) {
     killMainThread();
     bioKillThreads();
+    killIOThreads();
 }
 
 /* Scans the (assumed) x86 code starting at addr, for a max of `len`

src/networking.c

@@ -3021,6 +3021,23 @@ void initThreadedIO(void) {
     }
 }
 
+void killIOThreads(void) {
+    int err, j;
+    for (j = 0; j < server.io_threads_num; j++) {
+        if (io_threads[j] == pthread_self()) continue;
+        if (io_threads[j] && pthread_cancel(io_threads[j]) == 0) {
+            if ((err = pthread_join(io_threads[j],NULL)) != 0) {
+                serverLog(LL_WARNING,
+                    "IO thread(tid:%lu) can not be joined: %s",
+                        (unsigned long)io_threads[j], strerror(err));
+            } else {
+                serverLog(LL_WARNING,
+                    "IO thread(tid:%lu) terminated",(unsigned long)io_threads[j]);
+            }
+        }
+    }
+}
+
 void startThreadedIO(void) {
     if (tio_debug) { printf("S"); fflush(stdout); }
     if (tio_debug) printf("--- STARTING THREADED IO ---\n");

src/server.h

@@ -2460,6 +2460,7 @@ int memtest_preserving_test(unsigned long *m, size_t bytes, int passes);
 void mixDigest(unsigned char *digest, void *ptr, size_t len);
 void xorDigest(unsigned char *digest, void *ptr, size_t len);
 int populateCommandTableParseFlags(struct redisCommand *c, char *strflags);
+void killIOThreads(void);
 
 /* TLS stuff */
 void tlsInit(void);