qcacmn: Move locking for qdf_net_buf_debug_look_up to the colision list

At a cost of keeping 1023 more spinlocks in memory, we can avoid
spinlock contention between different hash keys while performing
the lookup.

Change-Id: Icca2bf0b49186176caf1ea40fb508efa7e7c89b4
CRs-Fixed: 1013620

qdf/linux/src/qdf_nbuf.c

@@ -528,10 +528,10 @@ struct qdf_nbuf_track_t {
 	size_t size;
 };
 
-spinlock_t g_qdf_net_buf_track_lock;
+static spinlock_t g_qdf_net_buf_track_lock[QDF_NET_BUF_TRACK_MAX_SIZE];
 typedef struct qdf_nbuf_track_t QDF_NBUF_TRACK;
 
-QDF_NBUF_TRACK *gp_qdf_net_buf_track_tbl[QDF_NET_BUF_TRACK_MAX_SIZE];
+static QDF_NBUF_TRACK *gp_qdf_net_buf_track_tbl[QDF_NET_BUF_TRACK_MAX_SIZE];
 
 /**
  * qdf_net_buf_debug_init() - initialize network buffer debug functionality
@@ -547,16 +547,11 @@ QDF_NBUF_TRACK *gp_qdf_net_buf_track_tbl[QDF_NET_BUF_TRACK_MAX_SIZE];
 void qdf_net_buf_debug_init(void)
 {
 	uint32_t i;
-	unsigned long irq_flag;
-
-	spin_lock_init(&g_qdf_net_buf_track_lock);
 
-	spin_lock_irqsave(&g_qdf_net_buf_track_lock, irq_flag);
-
-	for (i = 0; i < QDF_NET_BUF_TRACK_MAX_SIZE; i++)
+	for (i = 0; i < QDF_NET_BUF_TRACK_MAX_SIZE; i++) {
 		gp_qdf_net_buf_track_tbl[i] = NULL;
-
-	spin_unlock_irqrestore(&g_qdf_net_buf_track_lock, irq_flag);
+		spin_lock_init(&g_qdf_net_buf_track_lock[i]);
+	}
 
 	return;
 }
@@ -576,9 +571,8 @@ void qdf_net_buf_debug_exit(void)
 	QDF_NBUF_TRACK *p_node;
 	QDF_NBUF_TRACK *p_prev;
 
-	spin_lock_irqsave(&g_qdf_net_buf_track_lock, irq_flag);
-
 	for (i = 0; i < QDF_NET_BUF_TRACK_MAX_SIZE; i++) {
+		spin_lock_irqsave(&g_qdf_net_buf_track_lock[i], irq_flag);
 		p_node = gp_qdf_net_buf_track_tbl[i];
 		while (p_node) {
 			p_prev = p_node;
@@ -588,10 +582,9 @@ void qdf_net_buf_debug_exit(void)
 				  p_prev->file_name, p_prev->line_num,
 				  p_prev->size);
 		}
+		spin_unlock_irqrestore(&g_qdf_net_buf_track_lock[i], irq_flag);
 	}
 
-	spin_unlock_irqrestore(&g_qdf_net_buf_track_lock, irq_flag);
-
 	return;
 }
 EXPORT_SYMBOL(qdf_net_buf_debug_exit);
@@ -608,19 +601,17 @@ void qdf_net_buf_debug_clean(void)
 	QDF_NBUF_TRACK *p_node;
 	QDF_NBUF_TRACK *p_prev;
 
-	spin_lock_irqsave(&g_qdf_net_buf_track_lock, irq_flag);
-
 	for (i = 0; i < QDF_NET_BUF_TRACK_MAX_SIZE; i++) {
+		spin_lock_irqsave(&g_qdf_net_buf_track_lock[i], irq_flag);
 		p_node = gp_qdf_net_buf_track_tbl[i];
 		while (p_node) {
 			p_prev = p_node;
 			p_node = p_node->p_next;
 			qdf_mem_free(p_prev);
 		}
+		spin_unlock_irqrestore(&g_qdf_net_buf_track_lock[i], irq_flag);
 	}
 
-	spin_unlock_irqrestore(&g_qdf_net_buf_track_lock, irq_flag);
-
 	return;
 }
 EXPORT_SYMBOL(qdf_net_buf_debug_clean);
@@ -681,9 +672,9 @@ void qdf_net_buf_debug_add_node(qdf_nbuf_t net_buf, size_t size,
 
 	new_node = (QDF_NBUF_TRACK *) qdf_mem_malloc(sizeof(*new_node));
 
-	spin_lock_irqsave(&g_qdf_net_buf_track_lock, irq_flag);
-
 	i = qdf_net_buf_debug_hash(net_buf);
+	spin_lock_irqsave(&g_qdf_net_buf_track_lock[i], irq_flag);
+
 	p_node = qdf_net_buf_debug_look_up(net_buf);
 
 	if (p_node) {
@@ -712,7 +703,7 @@ void qdf_net_buf_debug_add_node(qdf_nbuf_t net_buf, size_t size,
 	}
 
 done:
-	spin_unlock_irqrestore(&g_qdf_net_buf_track_lock, irq_flag);
+	spin_unlock_irqrestore(&g_qdf_net_buf_track_lock[i], irq_flag);
 
 	return;
 }
@@ -732,9 +723,9 @@ void qdf_net_buf_debug_delete_node(qdf_nbuf_t net_buf)
 	unsigned long irq_flag;
 	QDF_NBUF_TRACK *p_prev;
 
-	spin_lock_irqsave(&g_qdf_net_buf_track_lock, irq_flag);
-
 	i = qdf_net_buf_debug_hash(net_buf);
+	spin_lock_irqsave(&g_qdf_net_buf_track_lock[i], irq_flag);
+
 	p_head = gp_qdf_net_buf_track_tbl[i];
 
 	/* Unallocated SKB */
@@ -770,7 +761,7 @@ done:
 		QDF_ASSERT(0);
 	}
 
-	spin_unlock_irqrestore(&g_qdf_net_buf_track_lock, irq_flag);
+	spin_unlock_irqrestore(&g_qdf_net_buf_track_lock[i], irq_flag);
 
 	return;
 }