Re: [PATCH v5 09/10] iommu/vt-d: Add trace events for device dma map/unmap

From: Lu Baolu
Date: Thu Jul 25 2019 - 22:25:34 EST


Hi,

On 7/25/19 8:26 PM, Steven Rostedt wrote:
On Thu, 25 Jul 2019 11:17:16 +0800
Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> wrote:

This adds trace support for the Intel IOMMU driver. It
also declares some events which could be used to trace
the events when an IOVA is being mapped or unmapped in
a domain.

Cc: Ashok Raj <ashok.raj@xxxxxxxxx>
Cc: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
Cc: Kevin Tian <kevin.tian@xxxxxxxxx>
Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
---
drivers/iommu/Makefile | 1 +
drivers/iommu/intel-trace.c | 14 +++++
include/trace/events/intel_iommu.h | 95 ++++++++++++++++++++++++++++++
3 files changed, 110 insertions(+)
create mode 100644 drivers/iommu/intel-trace.c
create mode 100644 include/trace/events/intel_iommu.h

This patch looks fine, but I don't see the use cases for anything but
trace_bounce_map_single() and trace_bounce_unmap_single() used.

This only adds trace event/point for this case. We will add more later.


Other than that.

Reviewed-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>

Thank you!

Best regards,
Baolu


-- Steve


diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile
index f13f36ae1af6..bfe27b2755bd 100644
--- a/drivers/iommu/Makefile
+++ b/drivers/iommu/Makefile
@@ -17,6 +17,7 @@ obj-$(CONFIG_ARM_SMMU) += arm-smmu.o
obj-$(CONFIG_ARM_SMMU_V3) += arm-smmu-v3.o
obj-$(CONFIG_DMAR_TABLE) += dmar.o
obj-$(CONFIG_INTEL_IOMMU) += intel-iommu.o intel-pasid.o
+obj-$(CONFIG_INTEL_IOMMU) += intel-trace.o
obj-$(CONFIG_INTEL_IOMMU_DEBUGFS) += intel-iommu-debugfs.o
obj-$(CONFIG_INTEL_IOMMU_SVM) += intel-svm.o
obj-$(CONFIG_IPMMU_VMSA) += ipmmu-vmsa.o
diff --git a/drivers/iommu/intel-trace.c b/drivers/iommu/intel-trace.c
new file mode 100644
index 000000000000..bfb6a6e37a88
--- /dev/null
+++ b/drivers/iommu/intel-trace.c
@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Intel IOMMU trace support
+ *
+ * Copyright (C) 2019 Intel Corporation
+ *
+ * Author: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
+ */
+
+#include <linux/string.h>
+#include <linux/types.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/intel_iommu.h>
diff --git a/include/trace/events/intel_iommu.h b/include/trace/events/intel_iommu.h
new file mode 100644
index 000000000000..3fdeaad93b2e
--- /dev/null
+++ b/include/trace/events/intel_iommu.h
@@ -0,0 +1,95 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Intel IOMMU trace support
+ *
+ * Copyright (C) 2019 Intel Corporation
+ *
+ * Author: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
+ */
+#ifdef CONFIG_INTEL_IOMMU
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM intel_iommu
+
+#if !defined(_TRACE_INTEL_IOMMU_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_INTEL_IOMMU_H
+
+#include <linux/tracepoint.h>
+#include <linux/intel-iommu.h>
+
+DECLARE_EVENT_CLASS(dma_map,
+ TP_PROTO(struct device *dev, dma_addr_t dev_addr, phys_addr_t phys_addr,
+ size_t size),
+
+ TP_ARGS(dev, dev_addr, phys_addr, size),
+
+ TP_STRUCT__entry(
+ __string(dev_name, dev_name(dev))
+ __field(dma_addr_t, dev_addr)
+ __field(phys_addr_t, phys_addr)
+ __field(size_t, size)
+ ),
+
+ TP_fast_assign(
+ __assign_str(dev_name, dev_name(dev));
+ __entry->dev_addr = dev_addr;
+ __entry->phys_addr = phys_addr;
+ __entry->size = size;
+ ),
+
+ TP_printk("dev=%s dev_addr=0x%llx phys_addr=0x%llx size=%zu",
+ __get_str(dev_name),
+ (unsigned long long)__entry->dev_addr,
+ (unsigned long long)__entry->phys_addr,
+ __entry->size)
+);
+
+DEFINE_EVENT(dma_map, bounce_map_single,
+ TP_PROTO(struct device *dev, dma_addr_t dev_addr, phys_addr_t phys_addr,
+ size_t size),
+ TP_ARGS(dev, dev_addr, phys_addr, size)
+);
+
+DEFINE_EVENT(dma_map, bounce_map_sg,
+ TP_PROTO(struct device *dev, dma_addr_t dev_addr, phys_addr_t phys_addr,
+ size_t size),
+ TP_ARGS(dev, dev_addr, phys_addr, size)
+);
+
+DECLARE_EVENT_CLASS(dma_unmap,
+ TP_PROTO(struct device *dev, dma_addr_t dev_addr, size_t size),
+
+ TP_ARGS(dev, dev_addr, size),
+
+ TP_STRUCT__entry(
+ __string(dev_name, dev_name(dev))
+ __field(dma_addr_t, dev_addr)
+ __field(size_t, size)
+ ),
+
+ TP_fast_assign(
+ __assign_str(dev_name, dev_name(dev));
+ __entry->dev_addr = dev_addr;
+ __entry->size = size;
+ ),
+
+ TP_printk("dev=%s dev_addr=0x%llx size=%zu",
+ __get_str(dev_name),
+ (unsigned long long)__entry->dev_addr,
+ __entry->size)
+);
+
+DEFINE_EVENT(dma_unmap, bounce_unmap_single,
+ TP_PROTO(struct device *dev, dma_addr_t dev_addr, size_t size),
+ TP_ARGS(dev, dev_addr, size)
+);
+
+DEFINE_EVENT(dma_unmap, bounce_unmap_sg,
+ TP_PROTO(struct device *dev, dma_addr_t dev_addr, size_t size),
+ TP_ARGS(dev, dev_addr, size)
+);
+
+#endif /* _TRACE_INTEL_IOMMU_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
+#endif /* CONFIG_INTEL_IOMMU */