diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c
index 7c9ac163d115..cb91dadeb465 100644
--- a/drivers/dma-buf/dma-buf.c
+++ b/drivers/dma-buf/dma-buf.c
@@ -115,6 +115,9 @@ static void dma_buf_release(struct dentry *dentry)
 	if (dmabuf->resv == (struct dma_resv *)&dmabuf[1])
 		dma_resv_fini(dmabuf->resv);
 
+	if (atomic64_read(&dmabuf->num_unique_refs))
+		pr_err("destroying dmabuf with non-zero task refs\n");
+
 	WARN_ON(!list_empty(&dmabuf->attachments));
 	module_put(dmabuf->owner);
 	kfree(dmabuf->name);
@@ -199,6 +202,8 @@ static int new_task_dmabuf_record(struct task_struct *task, struct dma_buf *dmab
 	rec->refcnt = 1;
 	list_add(&rec->node, &task->dmabuf_info->dmabufs);
 
+	atomic64_inc(&dmabuf->num_unique_refs);
+
 	return 0;
 }
 
@@ -276,6 +281,7 @@ void dma_buf_unaccount_task(struct dma_buf *dmabuf, struct task_struct *task)
 		list_del(&rec->node);
 		kfree(rec);
 		task->dmabuf_info->rss -= dmabuf->size;
+		atomic64_dec(&dmabuf->num_unique_refs);
 	}
 err:
 	spin_unlock(&task->dmabuf_info->lock);
@@ -851,6 +857,8 @@ struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info)
 		dmabuf->resv = resv;
 	}
 
+	atomic64_set(&dmabuf->num_unique_refs, 0);
+
 	file->private_data = dmabuf;
 	file->f_path.dentry->d_fsdata = dmabuf;
 	dmabuf->file = file;
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 6b91ddcab7e2..2eee67e06ffe 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -3397,6 +3397,39 @@ static const struct file_operations proc_dmabuf_rss_hwm_operations = {
 	.llseek		= seq_lseek,
 	.release	= single_release,
 };
+
+static int proc_dmabuf_pss_show(struct seq_file *m, struct pid_namespace *ns,
+		     struct pid *pid, struct task_struct *task)
+{
+	struct task_dma_buf_record *rec;
+	u64 pss = 0;
+
+	if (!task->dmabuf_info) {
+		pr_err("%s dmabuf accounting record was not allocated\n", __func__);
+		return -ENOMEM;
+	}
+
+	if (!(task->flags & PF_KTHREAD)) {
+		spin_lock(&task->dmabuf_info->lock);
+		list_for_each_entry(rec, &task->dmabuf_info->dmabufs, node) {
+			s64 refs = atomic64_read(&rec->dmabuf->num_unique_refs);
+
+			if (refs <= 0) {
+				pr_err("dmabuf has <= refs %lld\n", refs);
+				continue;
+			}
+
+			pss += rec->dmabuf->size / (size_t)refs;
+		}
+		spin_unlock(&task->dmabuf_info->lock);
+
+		seq_printf(m, "%llu\n", pss);
+	} else {
+		seq_puts(m, "0\n");
+	}
+
+	return 0;
+}
 #endif
 
 /*
@@ -3525,6 +3558,7 @@ static const struct pid_entry tgid_base_stuff[] = {
 #ifdef CONFIG_DMA_SHARED_BUFFER
 	ONE("dmabuf_rss", S_IRUGO, proc_dmabuf_rss_show),
 	REG("dmabuf_rss_hwm", S_IRUGO|S_IWUSR, proc_dmabuf_rss_hwm_operations),
+	ONE("dmabuf_pss", S_IRUGO, proc_dmabuf_pss_show),
 #endif
 };
 
diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h
index a362c8ba7a21..267bf322272f 100644
--- a/include/linux/dma-buf.h
+++ b/include/linux/dma-buf.h
@@ -25,6 +25,7 @@
 #include <linux/workqueue.h>
 #include <linux/android_kabi.h>
 #ifndef __GENKSYMS__
+#include <linux/atomic.h>
 #include <linux/refcount.h>
 #endif
 
@@ -534,6 +535,13 @@ struct dma_buf {
 	} *sysfs_entry;
 #endif
 
+	/**
+	 * @num_unique_refs:
+	 *
+	 * The number of tasks that reference this buffer. For calculating PSS.
+	 */
+	atomic64_t num_unique_refs;
+
 	ANDROID_KABI_RESERVE(1);
 	ANDROID_KABI_RESERVE(2);
 };