[PATCH] s390: qeth driver fixes [4/6]

[PATCH 7/9] s390: qeth driver fixes [4/6]

From: Frank Pavlic <fpavlic@de.ibm.com>
	- fix kernel crash due to race,
	  set card->state to SOFTSETUP after
	  card and card->dev are initialized properly.
	- remove CONFIG_QETH_PERF_STATS, use sysfs attribute instead,
	  as we want to have the ability to turn on/off the
	  statistics at runtime.
Signed-off-by: Frank Pavlic <fpavlic@de.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

drivers/s390/net/Kconfig

@@ -92,15 +92,6 @@ config QETH_VLAN
 	  If CONFIG_QETH is switched on, this option will include IEEE
 	  802.1q VLAN support in the qeth device driver.
 
-config QETH_PERF_STATS
-	bool "Performance statistics in /proc"
-	depends on QETH
-	help
-	  When switched on, this option will add a file in the proc-fs
-	  (/proc/qeth_perf_stats) containing performance statistics. It
-	  may slightly impact performance, so this is only recommended for
-	  internal tuning of the device driver.
-
 config CCWGROUP
  	tristate
 	default (LCS || CTC || QETH)

drivers/s390/net/qeth.h

@@ -176,7 +176,6 @@ extern struct ccwgroup_driver qeth_ccwgroup_driver;
 /**
  * card stuff
  */
-#ifdef CONFIG_QETH_PERF_STATS
 struct qeth_perf_stats {
 	unsigned int bufs_rec;
 	unsigned int bufs_sent;
@@ -211,8 +210,10 @@ struct qeth_perf_stats {
 	unsigned int large_send_cnt;
 	unsigned int sg_skbs_sent;
 	unsigned int sg_frags_sent;
+	/* initial values when measuring starts */
+	unsigned long initial_rx_packets;
+	unsigned long initial_tx_packets;
 };
-#endif /* CONFIG_QETH_PERF_STATS */
 
 /* Routing stuff */
 struct qeth_routing_info {
@@ -767,6 +768,7 @@ struct qeth_card_options {
 	int fake_ll;
 	int layer2;
 	enum qeth_large_send_types large_send;
+	int performance_stats;
 };
 
 /*
@@ -819,9 +821,7 @@ struct qeth_card {
 	struct list_head cmd_waiter_list;
 	/* QDIO buffer handling */
 	struct qeth_qdio_info qdio;
-#ifdef CONFIG_QETH_PERF_STATS
 	struct qeth_perf_stats perf_stats;
-#endif /* CONFIG_QETH_PERF_STATS */
 	int use_hard_stop;
 	int (*orig_hard_header)(struct sk_buff *,struct net_device *,
 				unsigned short,void *,void *,unsigned);
@@ -1049,13 +1049,11 @@ qeth_get_arphdr_type(int cardtype, int linktype)
 	}
 }
 
-#ifdef CONFIG_QETH_PERF_STATS
 static inline int
 qeth_get_micros(void)
 {
 	return (int) (get_clock() >> 12);
 }
-#endif
 
 static inline int
 qeth_get_qdio_q_format(struct qeth_card *card)

drivers/s390/net/qeth_eddp.c

@@ -179,9 +179,8 @@ qeth_eddp_fill_buffer(struct qeth_qdio_out_q *queue,
 			flush_cnt++;
 		}
 	} else {
-#ifdef CONFIG_QETH_PERF_STATS
+		if (queue->card->options.performance_stats)
 			queue->card->perf_stats.skbs_sent_pack++;
-#endif
 		QETH_DBF_TEXT(trace, 6, "fillbfpa");
 		if (buf->next_element_to_fill >=
 				QETH_MAX_BUFFER_ELEMENTS(queue->card)) {

drivers/s390/net/qeth_main.c

@@ -1073,6 +1073,7 @@ qeth_set_intial_options(struct qeth_card *card)
 		card->options.layer2 = 1;
 	else
 		card->options.layer2 = 0;
+	card->options.performance_stats = 1;
 }
 
 /**
@@ -2564,9 +2565,8 @@ qeth_process_inbound_buffer(struct qeth_card *card,
 	/* get first element of current buffer */
 	element = (struct qdio_buffer_element *)&buf->buffer->element[0];
 	offset = 0;
-#ifdef CONFIG_QETH_PERF_STATS
+	if (card->options.performance_stats)
 		card->perf_stats.bufs_rec++;
-#endif
 	while((skb = qeth_get_next_skb(card, buf->buffer, &element,
 				       &offset, &hdr))) {
 		skb->dev = card->dev;
@@ -2697,17 +2697,18 @@ qeth_queue_input_buffer(struct qeth_card *card, int index)
 		 * 'index') un-requeued -> this buffer is the first buffer that
 		 * will be requeued the next time
 		 */
-#ifdef CONFIG_QETH_PERF_STATS
+		if (card->options.performance_stats) {
 			card->perf_stats.inbound_do_qdio_cnt++;
-		card->perf_stats.inbound_do_qdio_start_time = qeth_get_micros();
-#endif
+			card->perf_stats.inbound_do_qdio_start_time =
+				qeth_get_micros();
+		}
 		rc = do_QDIO(CARD_DDEV(card),
 			     QDIO_FLAG_SYNC_INPUT | QDIO_FLAG_UNDER_INTERRUPT,
 			     0, queue->next_buf_to_init, count, NULL);
-#ifdef CONFIG_QETH_PERF_STATS
-		card->perf_stats.inbound_do_qdio_time += qeth_get_micros() -
+		if (card->options.performance_stats)
+			card->perf_stats.inbound_do_qdio_time +=
+				qeth_get_micros() -
 				card->perf_stats.inbound_do_qdio_start_time;
-#endif
 		if (rc){
 			PRINT_WARN("qeth_queue_input_buffer's do_QDIO "
 				   "return %i (device %s).\n",
@@ -2743,10 +2744,10 @@ qeth_qdio_input_handler(struct ccw_device * ccwdev, unsigned int status,
 	QETH_DBF_TEXT(trace, 6, "qdinput");
 	card = (struct qeth_card *) card_ptr;
 	net_dev = card->dev;
-#ifdef CONFIG_QETH_PERF_STATS
+	if (card->options.performance_stats) {
 		card->perf_stats.inbound_cnt++;
 		card->perf_stats.inbound_start_time = qeth_get_micros();
-#endif
+	}
 	if (status & QDIO_STATUS_LOOK_FOR_ERROR) {
 		if (status & QDIO_STATUS_ACTIVATE_CHECK_CONDITION){
 			QETH_DBF_TEXT(trace, 1,"qdinchk");
@@ -2768,10 +2769,9 @@ qeth_qdio_input_handler(struct ccw_device * ccwdev, unsigned int status,
 		qeth_put_buffer_pool_entry(card, buffer->pool_entry);
 		qeth_queue_input_buffer(card, index);
 	}
-#ifdef CONFIG_QETH_PERF_STATS
+	if (card->options.performance_stats)
 		card->perf_stats.inbound_time += qeth_get_micros() -
 			card->perf_stats.inbound_start_time;
-#endif
 }
 
 static inline int
@@ -2861,10 +2861,11 @@ qeth_flush_buffers(struct qeth_qdio_out_q *queue, int under_int,
 	}
 
 	queue->card->dev->trans_start = jiffies;
-#ifdef CONFIG_QETH_PERF_STATS
+	if (queue->card->options.performance_stats) {
 		queue->card->perf_stats.outbound_do_qdio_cnt++;
-	queue->card->perf_stats.outbound_do_qdio_start_time = qeth_get_micros();
-#endif
+		queue->card->perf_stats.outbound_do_qdio_start_time =
+			qeth_get_micros();
+	}
 	if (under_int)
 		rc = do_QDIO(CARD_DDEV(queue->card),
 			     QDIO_FLAG_SYNC_OUTPUT | QDIO_FLAG_UNDER_INTERRUPT,
@@ -2872,10 +2873,10 @@ qeth_flush_buffers(struct qeth_qdio_out_q *queue, int under_int,
 	else
 		rc = do_QDIO(CARD_DDEV(queue->card), QDIO_FLAG_SYNC_OUTPUT,
 			     queue->queue_no, index, count, NULL);
-#ifdef CONFIG_QETH_PERF_STATS
-	queue->card->perf_stats.outbound_do_qdio_time += qeth_get_micros() -
+	if (queue->card->options.performance_stats)
+		queue->card->perf_stats.outbound_do_qdio_time +=
+			qeth_get_micros() -
 			queue->card->perf_stats.outbound_do_qdio_start_time;
-#endif
 	if (rc){
 		QETH_DBF_TEXT(trace, 2, "flushbuf");
 		QETH_DBF_TEXT_(trace, 2, " err%d", rc);
@@ -2887,9 +2888,8 @@ qeth_flush_buffers(struct qeth_qdio_out_q *queue, int under_int,
 		return;
 	}
 	atomic_add(count, &queue->used_buffers);
-#ifdef CONFIG_QETH_PERF_STATS
+	if (queue->card->options.performance_stats)
 		queue->card->perf_stats.bufs_sent += count;
-#endif
 }
 
 /*
@@ -2904,9 +2904,8 @@ qeth_switch_to_packing_if_needed(struct qeth_qdio_out_q *queue)
 		    >= QETH_HIGH_WATERMARK_PACK){
 			/* switch non-PACKING -> PACKING */
 			QETH_DBF_TEXT(trace, 6, "np->pack");
-#ifdef CONFIG_QETH_PERF_STATS
+			if (queue->card->options.performance_stats)
 				queue->card->perf_stats.sc_dp_p++;
-#endif
 			queue->do_pack = 1;
 		}
 	}
@@ -2929,9 +2928,8 @@ qeth_switch_to_nonpacking_if_needed(struct qeth_qdio_out_q *queue)
 		    <= QETH_LOW_WATERMARK_PACK) {
 			/* switch PACKING -> non-PACKING */
 			QETH_DBF_TEXT(trace, 6, "pack->np");
-#ifdef CONFIG_QETH_PERF_STATS
+			if (queue->card->options.performance_stats)
 				queue->card->perf_stats.sc_p_dp++;
-#endif
 			queue->do_pack = 0;
 			/* flush packing buffers */
 			buffer = &queue->bufs[queue->next_buf_to_fill];
@@ -2999,11 +2997,10 @@ qeth_check_outbound_queue(struct qeth_qdio_out_q *queue)
 			    !atomic_read(&queue->set_pci_flags_count))
 				flush_cnt +=
 					qeth_flush_buffers_on_no_pci(queue);
-#ifdef CONFIG_QETH_PERF_STATS
-			if (q_was_packing)
+			if (queue->card->options.performance_stats &&
+			    q_was_packing)
 				queue->card->perf_stats.bufs_sent_pack +=
 					flush_cnt;
-#endif
 			if (flush_cnt)
 				qeth_flush_buffers(queue, 1, index, flush_cnt);
 			atomic_set(&queue->state, QETH_OUT_Q_UNLOCKED);
@@ -3033,10 +3030,11 @@ qeth_qdio_output_handler(struct ccw_device * ccwdev, unsigned int status,
 			return;
 		}
 	}
-#ifdef CONFIG_QETH_PERF_STATS
+	if (card->options.performance_stats) {
 		card->perf_stats.outbound_handler_cnt++;
-	card->perf_stats.outbound_handler_start_time = qeth_get_micros();
-#endif
+		card->perf_stats.outbound_handler_start_time =
+			qeth_get_micros();
+	}
 	for(i = first_element; i < (first_element + count); ++i){
 		buffer = &queue->bufs[i % QDIO_MAX_BUFFERS_PER_Q];
 		/*we only handle the KICK_IT error by doing a recovery */
@@ -3055,10 +3053,9 @@ qeth_qdio_output_handler(struct ccw_device * ccwdev, unsigned int status,
 		qeth_check_outbound_queue(queue);
 
 	netif_wake_queue(queue->card->dev);
-#ifdef CONFIG_QETH_PERF_STATS
+	if (card->options.performance_stats)
 		card->perf_stats.outbound_handler_time += qeth_get_micros() -
 			card->perf_stats.outbound_handler_start_time;
-#endif
 }
 
 static void
@@ -3684,10 +3681,10 @@ qeth_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
 		/* return OK; otherwise ksoftirqd goes to 100% */
 		return NETDEV_TX_OK;
 	}
-#ifdef CONFIG_QETH_PERF_STATS
+	if (card->options.performance_stats) {
 		card->perf_stats.outbound_cnt++;
 		card->perf_stats.outbound_start_time = qeth_get_micros();
-#endif
+	}
 	netif_stop_queue(dev);
 	if ((rc = qeth_send_packet(card, skb))) {
 		if (rc == -EBUSY) {
@@ -3701,10 +3698,9 @@ qeth_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
 		}
 	}
 	netif_wake_queue(dev);
-#ifdef CONFIG_QETH_PERF_STATS
+	if (card->options.performance_stats)
 		card->perf_stats.outbound_time += qeth_get_micros() -
 			card->perf_stats.outbound_start_time;
-#endif
 	return rc;
 }
 
@@ -4213,9 +4209,8 @@ qeth_fill_buffer(struct qeth_qdio_out_q *queue,
 		flush_cnt = 1;
 	} else {
 		QETH_DBF_TEXT(trace, 6, "fillbfpa");
-#ifdef CONFIG_QETH_PERF_STATS
+		if (queue->card->options.performance_stats)
 			queue->card->perf_stats.skbs_sent_pack++;
-#endif
 		if (buf->next_element_to_fill >=
 				QETH_MAX_BUFFER_ELEMENTS(queue->card)) {
 			/*
@@ -4380,10 +4375,8 @@ qeth_do_send_packet(struct qeth_card *card, struct qeth_qdio_out_q *queue,
 			qeth_flush_buffers(queue, 0, start_index, flush_count);
 	}
 	/* at this point the queue is UNLOCKED again */
-#ifdef CONFIG_QETH_PERF_STATS
-	if (do_pack)
+	if (queue->card->options.performance_stats && do_pack)
 		queue->card->perf_stats.bufs_sent_pack += flush_count;
-#endif /* CONFIG_QETH_PERF_STATS */
 
 	return rc;
 }
@@ -4420,10 +4413,8 @@ qeth_send_packet(struct qeth_card *card, struct sk_buff *skb)
 	enum qeth_large_send_types large_send = QETH_LARGE_SEND_NO;
 	struct qeth_eddp_context *ctx = NULL;
 	int tx_bytes = skb->len;
-#ifdef CONFIG_QETH_PERF_STATS
 	unsigned short nr_frags = skb_shinfo(skb)->nr_frags;
 	unsigned short tso_size = skb_shinfo(skb)->gso_size;
-#endif
 	struct sk_buff *new_skb, *new_skb2;
 	int rc;
 
@@ -4505,7 +4496,7 @@ qeth_send_packet(struct qeth_card *card, struct sk_buff *skb)
 		card->stats.tx_bytes += tx_bytes;
 		if (new_skb != skb)
 			dev_kfree_skb_any(skb);
-#ifdef CONFIG_QETH_PERF_STATS
+		if (card->options.performance_stats) {
 			if (tso_size &&
 			    !(large_send == QETH_LARGE_SEND_NO)) {
 				card->perf_stats.large_send_bytes += tx_bytes;
@@ -4517,7 +4508,7 @@ qeth_send_packet(struct qeth_card *card, struct sk_buff *skb)
 				card->perf_stats.sg_frags_sent +=
 					nr_frags + 1;
 			}
-#endif /* CONFIG_QETH_PERF_STATS */
+		}
 	} else {
 		card->stats.tx_dropped++;
 		__qeth_free_new_skb(skb, new_skb);
@@ -7878,12 +7869,12 @@ __qeth_set_online(struct ccwgroup_device *gdev, int recovery_mode)
 		QETH_DBF_TEXT_(setup, 2, "5err%d", rc);
 		goto out_remove;
 	}
-	card->state = CARD_STATE_SOFTSETUP;
 
 	if ((rc = qeth_init_qdio_queues(card))){
 		QETH_DBF_TEXT_(setup, 2, "6err%d", rc);
 		goto out_remove;
 	}
+	card->state = CARD_STATE_SOFTSETUP;
 	netif_carrier_on(card->dev);
 
 	qeth_set_allowed_threads(card, 0xffffffff, 0);

drivers/s390/net/qeth_proc.c

@@ -173,7 +173,6 @@ static struct file_operations qeth_procfile_fops = {
 #define QETH_PERF_PROCFILE_NAME "qeth_perf"
 static struct proc_dir_entry *qeth_perf_procfile;
 
-#ifdef CONFIG_QETH_PERF_STATS
 static int
 qeth_perf_procfile_seq_show(struct seq_file *s, void *it)
 {
@@ -192,14 +191,21 @@ qeth_perf_procfile_seq_show(struct seq_file *s, void *it)
 			CARD_DDEV_ID(card),
 			QETH_CARD_IFNAME(card)
 		  );
+	if (!card->options.performance_stats)
+		seq_printf(s, "Performance statistics are deactivated.\n");
 	seq_printf(s, "  Skb's/buffers received                 : %lu/%u\n"
 		      "  Skb's/buffers sent                     : %lu/%u\n\n",
-		        card->stats.rx_packets, card->perf_stats.bufs_rec,
-		        card->stats.tx_packets, card->perf_stats.bufs_sent
+		        card->stats.rx_packets -
+				card->perf_stats.initial_rx_packets,
+			card->perf_stats.bufs_rec,
+		        card->stats.tx_packets -
+				card->perf_stats.initial_tx_packets,
+			card->perf_stats.bufs_sent
 		  );
 	seq_printf(s, "  Skb's/buffers sent without packing     : %lu/%u\n"
 		      "  Skb's/buffers sent with packing        : %u/%u\n\n",
-		   card->stats.tx_packets - card->perf_stats.skbs_sent_pack,
+		   card->stats.tx_packets - card->perf_stats.initial_tx_packets
+					  - card->perf_stats.skbs_sent_pack,
 		   card->perf_stats.bufs_sent - card->perf_stats.bufs_sent_pack,
 		   card->perf_stats.skbs_sent_pack,
 		   card->perf_stats.bufs_sent_pack
@@ -275,11 +281,6 @@ static struct file_operations qeth_perf_procfile_fops = {
 	.release = seq_release,
 };
 
-#define qeth_perf_procfile_created qeth_perf_procfile
-#else
-#define qeth_perf_procfile_created 1
-#endif /* CONFIG_QETH_PERF_STATS */
-
 int __init
 qeth_create_procfs_entries(void)
 {
@@ -288,15 +289,13 @@ qeth_create_procfs_entries(void)
 	if (qeth_procfile)
 		qeth_procfile->proc_fops = &qeth_procfile_fops;
 
-#ifdef CONFIG_QETH_PERF_STATS
 	qeth_perf_procfile = create_proc_entry(QETH_PERF_PROCFILE_NAME,
 					   S_IFREG | 0444, NULL);
 	if (qeth_perf_procfile)
 		qeth_perf_procfile->proc_fops = &qeth_perf_procfile_fops;
-#endif /* CONFIG_QETH_PERF_STATS */
 
 	if (qeth_procfile &&
-	    qeth_perf_procfile_created)
+	    qeth_perf_procfile)
 		return 0;
 	else
 		return -ENOMEM;

drivers/s390/net/qeth_sys.c

@@ -742,6 +742,47 @@ qeth_dev_layer2_store(struct device *dev, struct device_attribute *attr, const c
 static DEVICE_ATTR(layer2, 0644, qeth_dev_layer2_show,
 		   qeth_dev_layer2_store);
 
+static ssize_t
+qeth_dev_performance_stats_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct qeth_card *card = dev->driver_data;
+
+	if (!card)
+		return -EINVAL;
+
+	return sprintf(buf, "%i\n", card->options.performance_stats ? 1:0);
+}
+
+static ssize_t
+qeth_dev_performance_stats_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct qeth_card *card = dev->driver_data;
+	char *tmp;
+	int i;
+
+	if (!card)
+		return -EINVAL;
+
+	i = simple_strtoul(buf, &tmp, 16);
+	if ((i == 0) || (i == 1)) {
+		if (i == card->options.performance_stats)
+			return count;
+		card->options.performance_stats = i;
+		if (i == 0)
+			memset(&card->perf_stats, 0,
+				sizeof(struct qeth_perf_stats));
+		card->perf_stats.initial_rx_packets = card->stats.rx_packets;
+		card->perf_stats.initial_tx_packets = card->stats.tx_packets;
+	} else {
+		PRINT_WARN("performance_stats: write 0 or 1 to this file!\n");
+		return -EINVAL;
+	}
+	return count;
+}
+
+static DEVICE_ATTR(performance_stats, 0644, qeth_dev_performance_stats_show,
+		   qeth_dev_performance_stats_store);
+
 static ssize_t
 qeth_dev_large_send_show(struct device *dev, struct device_attribute *attr, char *buf)
 {
@@ -928,6 +969,7 @@ static struct device_attribute * qeth_device_attrs[] = {
 	&dev_attr_canonical_macaddr,
 	&dev_attr_layer2,
 	&dev_attr_large_send,
+	&dev_attr_performance_stats,
 	NULL,
 };