Merge "generic_vm_defconfig: virtual io: Enable debug options"

arch/arm64/configs/generic_vm_defconfig

@@ -121,6 +121,7 @@ CONFIG_DMABUF_HEAPS=y
 CONFIG_UIO=y
 CONFIG_VIRTIO_MMIO=y
 CONFIG_VIRTIO_MMIO_SWIOTLB=y
+CONFIG_GH_VIRTIO_DEBUG=y
 CONFIG_ANDROID_VENDOR_HOOKS=y
 CONFIG_EXT4_FS=y
 CONFIG_EXT4_FS_POSIX_ACL=y

drivers/block/virtio_blk.c

@@ -16,6 +16,9 @@
 #include <linux/blk-mq-virtio.h>
 #include <linux/numa.h>
 #include <uapi/linux/virtio_ring.h>
+#ifdef CONFIG_GH_VIRTIO_DEBUG
+#include <trace/events/gh_virtio_frontend.h>
+#endif
 
 #define PART_BITS 4
 #define VQ_NAME_LEN 16
@@ -285,6 +288,9 @@ static void virtblk_done(struct virtqueue *vq)
 
 			if (likely(!blk_should_fake_timeout(req->q)))
 				blk_mq_complete_request(req);
+#ifdef CONFIG_GH_VIRTIO_DEBUG
+			trace_virtio_block_done(vq->vdev->index, req_op(req), blk_rq_pos(req));
+#endif
 			req_done = true;
 		}
 		if (unlikely(virtqueue_is_broken(vq)))
@@ -351,6 +357,10 @@ static blk_status_t virtio_queue_rq(struct blk_mq_hw_ctx *hctx,
 
 	spin_lock_irqsave(&vblk->vqs[qid].lock, flags);
 	err = virtblk_add_req(vblk->vqs[qid].vq, vbr);
+#ifdef CONFIG_GH_VIRTIO_DEBUG
+	trace_virtio_block_submit(vblk->vqs[qid].vq->vdev->index,
+		vbr->out_hdr.type, vbr->out_hdr.sector, vbr->out_hdr.ioprio, err);
+#endif
 	if (err) {
 		virtqueue_kick(vblk->vqs[qid].vq);
 		/* Don't stop the queue if -ENOMEM: we may have failed to

drivers/virtio/Kconfig

@@ -167,6 +167,15 @@ config VIRTIO_MMIO_SWIOTLB
 	  shared with another virtual machine which is hosting virtio
 	  backend drivers.
 
+config GH_VIRTIO_DEBUG
+	bool "Enable debug features for virtio front-end drivers on Gunyah Hypervisor"
+	depends on VIRTIO_MMIO
+	help
+	  Activating this feature provides additional tracepoints in various
+	  virtio drivers that will be useful to debug virtio transactions.
+	  Currently virtio block driver and mmio transport provide few
+	  tracepoints when this feature is enabled.
+
 config VIRTIO_MMIO_CMDLINE_DEVICES
 	bool "Memory mapped virtio devices parameter parsing"
 	depends on VIRTIO_MMIO

drivers/virtio/virtio_mmio.c

@@ -70,6 +70,13 @@
 #include <linux/virtio_config.h>
 #include <uapi/linux/virtio_mmio.h>
 #include <linux/virtio_ring.h>
+
+#ifdef CONFIG_GH_VIRTIO_DEBUG
+#define CREATE_TRACE_POINTS
+#include <trace/events/gh_virtio_frontend.h>
+#undef CREATE_TRACE_POINTS
+#endif
+
 #ifdef CONFIG_VIRTIO_MMIO_SWIOTLB
 #include <linux/swiotlb.h>
 #include <linux/dma-direct.h>
@@ -296,6 +303,9 @@ static bool vm_notify(struct virtqueue *vq)
 {
 	struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vq->vdev);
 
+#ifdef CONFIG_GH_VIRTIO_DEBUG
+	trace_virtio_mmio_vm_notify(vq->vdev->index, vq->index);
+#endif
 	/* We write the queue's selector into the notification register to
 	 * signal the other end */
 	writel(vq->index, vm_dev->base + VIRTIO_MMIO_QUEUE_NOTIFY);
@@ -313,6 +323,10 @@ static irqreturn_t vm_interrupt(int irq, void *opaque)
 
 	/* Read and acknowledge interrupts */
 	status = readl(vm_dev->base + VIRTIO_MMIO_INTERRUPT_STATUS);
+#ifdef CONFIG_GH_VIRTIO_DEBUG
+	trace_virtio_mmio_vm_interrupt(vm_dev->vdev.index, status);
+#endif
+
 	writel(status, vm_dev->base + VIRTIO_MMIO_INTERRUPT_ACK);
 
 	if (unlikely(status & VIRTIO_MMIO_INT_CONFIG)) {

drivers/virtio/virtio_ring.c

@@ -12,6 +12,9 @@
 #include <linux/hrtimer.h>
 #include <linux/dma-mapping.h>
 #include <linux/spinlock.h>
+#ifdef CONFIG_GH_VIRTIO_DEBUG
+#include <trace/events/gh_virtio_frontend.h>
+#endif
 #include <xen/xen.h>
 
 #ifdef DEBUG
@@ -656,6 +659,11 @@ static inline int virtqueue_add_split(struct virtqueue *_vq,
 
 	pr_debug("Added buffer head %i to %p\n", head, vq);
 	END_USE(vq);
+#ifdef CONFIG_GH_VIRTIO_DEBUG
+	trace_virtio_vring_split_add(_vq->vdev->index, head,
+			vq->split.avail_idx_shadow-1, descs_used, vq->vq.num_free);
+#endif
+
 
 	/* This is very unlikely, but theoretically possible.  Kick
 	 * just in case. */
@@ -745,6 +753,10 @@ static void detach_buf_split(struct vring_virtqueue *vq, unsigned int head,
 	/* Plus final descriptor */
 	vq->vq.num_free++;
 
+#ifdef CONFIG_GH_VIRTIO_DEBUG
+	trace_virtio_detach_buf(vq->vq.vdev->index, vq->free_head, vq->vq.num_free);
+#endif
+
 	if (vq->indirect) {
 		struct vring_desc *indir_desc =
 				vq->split.desc_state[head].indir_desc;
@@ -792,6 +804,11 @@ static void *virtqueue_get_buf_ctx_split(struct virtqueue *_vq,
 		return NULL;
 	}
 
+#ifdef CONFIG_GH_VIRTIO_DEBUG
+	trace_virtio_get_buf_ctx_split(_vq->vdev->index, vq->last_used_idx,
+			virtio16_to_cpu(vq->vq.vdev, vq->split.vring.used->idx));
+#endif
+
 	if (!more_used_split(vq)) {
 		pr_debug("No more buffers in queue\n");
 		END_USE(vq);

include/trace/events/gh_virtio_frontend.h

@@ -146,9 +146,9 @@ TRACE_EVENT(virtio_block_done,
 TRACE_EVENT(virtio_block_submit,
 
 	TP_PROTO(unsigned int dev_index, unsigned int type, unsigned int sector,
-				unsigned int ioprio, int err, unsigned int num),
+				unsigned int ioprio, int err),
 
-	TP_ARGS(dev_index, type, sector, ioprio, err, num),
+	TP_ARGS(dev_index, type, sector, ioprio, err),
 
 	TP_STRUCT__entry(
 		__field(unsigned int,	dev_index)
@@ -156,7 +156,6 @@ TRACE_EVENT(virtio_block_submit,
 		__field(unsigned int,	sector)
 		__field(unsigned int,	ioprio)
 		__field(int,	err)
-		__field(unsigned int,	num)
 	),
 
 	TP_fast_assign(
@@ -165,12 +164,10 @@ TRACE_EVENT(virtio_block_submit,
 		__entry->sector		= sector;
 		__entry->ioprio		= ioprio;
 		__entry->err		= err;
-		__entry->num		= num;
 	),
 
-	TP_printk("virtio%u type %x sector %u ioprio %u num %d err %d",
-			__entry->dev_index, __entry->type, __entry->sector,
-			__entry->ioprio, __entry->num, __entry->err)
+	TP_printk("virtio%u type %x sector %u ioprio %u err %d", __entry->dev_index,
+			__entry->type, __entry->sector, __entry->ioprio, __entry->err)
 );
 
 #endif /* _TRACE_GH_VIRTIO_FRONTEND_H */