client: improve thread naming

kernel/mars_client.c

@@ -54,12 +54,56 @@ int max_client_channels = 2;
 
 int max_client_bulk = 16;
 
+/* //////////////////////// human readable numbers //////////////////////// */
+
+#define MAX_HUMAN_NR 512
+
+struct human_number_generator {
+	int hum_got;
+	u8  hum_wrap;
+	u8  hum_table[MAX_HUMAN_NR];
+};
+
+typedef u8 human_numbers_t[MAX_HUMAN_NR];
+
+/* No locking necessary for now (no parallelism).
+ */
+static
+int get_human_nr(struct human_number_generator *hum_gen)
+{
+	int restarted = 0;
+	int searched = MAX_HUMAN_NR;
+	int res = (hum_gen->hum_got + 1) % MAX_HUMAN_NR;
+
+ restart:
+	while (searched-- >= 0) {
+		u8 cand = hum_gen->hum_table[res];
+		if (cand == hum_gen->hum_wrap) {
+			hum_gen->hum_table[res]++;
+			return res;
+		}
+	}
+	/* no candidate found: aliases are no longer avoidable */
+	hum_gen->hum_wrap = (hum_gen->hum_wrap + 1) % MAX_HUMAN_NR;
+	if (!restarted++)
+		goto restart;
+	/* fallback is now exhausted: we need to lie */
+	return 0;
+}
+
+static
+void put_human_nr(struct human_number_generator *hum_gen, int nr)
+{
+	int index = nr % MAX_HUMAN_NR;
+	hum_gen->hum_table[index] = hum_gen->hum_wrap;
+}
+
+static struct human_number_generator global_numbers;
+
 ///////////////////////// own helper functions ////////////////////////
 
 static atomic_t sender_count = ATOMIC_INIT(0);
 
-static int thread_count = 0;
-
 static
 void _do_resubmit(struct client_channel *ch)
 {
@@ -176,7 +220,12 @@ int _setup_channel(struct client_bundle *bundle, int ch_nr)
 	ch->socket.s_recv_abort = mars_client_abort;
 	ch->is_open = true;
 
-	ch->receiver.thread = brick_thread_create(receiver_thread, ch, "mars_receiver%d.%d.%d", bundle->thread_count, ch_nr, ch->thread_count++);
+	ch->receiver.thread =
+		brick_thread_create(receiver_thread, ch,
+				    "mars_rcv%d.%d/%d",
+				    bundle->last_thread_nr,
+				    ch->thread_restart_count++,
+				    ch_nr);
 	if (unlikely(!ch->receiver.thread)) {
 		MARS_ERR("cannot start receiver thread %d, status = %d\n", ch_nr, status);
 		status = -ENOENT;
@@ -369,9 +418,13 @@ int _setup_bundle(struct client_bundle *bundle, const char *str)
 	}
 	*bundle->host++ = '\0';
 
-	bundle->thread_count = thread_count++;
-	bundle->sender.thread = brick_thread_create(sender_thread, bundle, "mars_sender%d", bundle->thread_count);
+	bundle->last_thread_nr = get_human_nr(&global_numbers);
+	bundle->sender.thread =
+		brick_thread_create(sender_thread, bundle,
+				    "mars_snd%d",
+				    bundle->last_thread_nr);
 	if (unlikely(!bundle->sender.thread)) {
+		put_human_nr(&global_numbers, bundle->last_thread_nr);
 		MARS_ERR("cannot start sender thread for '%s' @%s\n",
 			 bundle->path,
 			 bundle->host);
@@ -887,11 +940,11 @@ static int sender_thread(void *data)
 		// timeouting is a rather expensive operation, don't do it too often
 		if (do_timeout) {
 			do_timeout = false;
-			_maintain_bundle(&output->bundle);
+			_maintain_bundle(bundle);
 			_do_timeout_all(output, false);
 		}
 
-		brick_wait_smp(output->bundle.sender_event,
+		brick_wait_smp(bundle->sender_event,
 						 !list_empty(&output->mref_list) ||
 						 output->get_info,
 						 2 * HZ);
@@ -912,8 +965,8 @@ static int sender_thread(void *data)
 			status = _request_info(ch);
 			if (unlikely(status < 0)) {
 				MARS_WRN("cannot send info request '%s' @%s, status = %d\n",
-					 output->bundle.path,
-					 output->bundle.host,
+					 bundle->path,
+					 bundle->host,
 					 status);
 				do_timeout = true;
 				brick_msleep(1000);
@@ -995,8 +1048,8 @@ static int sender_thread(void *data)
 			ch = NULL;
 			// retry submission on next occasion..
 			MARS_WRN("mref send '%s' @%s failed, status = %d\n",
-				 output->bundle.path,
-				 output->bundle.host,
+				 bundle->path,
+				 bundle->host,
 				 status);
 
 			brick_msleep(100);
@@ -1006,8 +1059,8 @@ static int sender_thread(void *data)
 
 	if (unlikely(status < 0)) {
 		MARS_WRN("sender thread '%s' @%s terminated with status = %d\n",
-			 output->bundle.path,
-			 output->bundle.host,
+			 bundle->path,
+			 bundle->host,
 			 status);
 	}
 
@@ -1023,9 +1076,10 @@ static int sender_thread(void *data)
 	if (!atomic_dec_return(&sender_count))
 		mars_limit_reset(&client_limiter);
 
-	brick_wake_smp(&output->bundle.sender_event);
-	MARS_DBG("sender terminated\n");
 	atomic_dec(&brick->sender_count);
+	put_human_nr(&global_numbers, bundle->last_thread_nr);
+	brick_wake_smp(&bundle->sender_event);
+	MARS_DBG("sender terminated\n");
 	atomic_dec(&client_sender_count);
 	return status;
 }

kernel/mars_client.h

@@ -81,8 +81,8 @@ struct client_channel {
 	struct list_head wait_list;
 	struct client_output *output;
 	long current_space;
-	int thread_count;
 	int recv_error;
+	int thread_restart_count;
 	int ch_nr;
 	bool is_used;
 	bool is_open;
@@ -93,7 +93,7 @@ struct client_bundle {
 	char *host;
 	char *path;
 	struct mars_tcp_params *params;
-	int thread_count;
+	int last_thread_nr;
 	int old_channel;
 	wait_queue_head_t sender_event;
 	struct client_threadinfo sender;