[PATCH 0/7] iommu: Add event tracing feature to iommu

[PATCH 0/7] iommu: Add event tracing feature to iommu

[Shuah Khan]

This patch set adds tracing feature to iommu driver to report various
iommu events. Classes iommu_group, iommu_device, and iommu_map_unmap
are defined.

iommu_group class events can be enabled to trigger when devices get added
to and removed from an iommu group. Trace information includes iommu group
id and device name.

iommu:add_device_to_group
iommu:remove_device_from_group

iommu_device class events can be enabled to trigger when devices are attached
to and detached from a domain. Trace information includes device name.

iommu:attach_device_to_domain
iommu:detach_device_from_domain

iommu_map_unmap class events can be enabled to trigger when iommu map and
unmap iommu ops complete. Trace information includes iova, physical address
(map event only), and size.

iommu:map
iommu:unmap

In addition to defining the new traces, iommu driver is changed to call trace
events.

Changes since the last patch set:
- Addressed feedback: removed iommu_amd_event class.
- Generated patch with the new trace event defines.
- Generated individual patches for each trace event call in iommu driver

Shuah Khan (7):
  iommu: Add event tracing feature to iommu
  iommu: Change iommu driver to call add_device_to_group trace event
  iommu: Change iommu driver to call remove_device_to_group trace event
  iommu: Change iommu driver to call attach_device_to_domain trace
    event
  iommu: Change iommu driver to call detach_device_to_domain trace
    event
  iommu: Change iommu driver to call map trace event
  iommu: Change iommu driver to call unmap trace event

 drivers/iommu/Makefile       |    1 +
 drivers/iommu/iommu-traces.c |   24 ++++++++
 drivers/iommu/iommu.c        |   15 ++++-
 include/trace/events/iommu.h |  129 ++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 168 insertions(+), 1 deletion(-)
 create mode 100644 drivers/iommu/iommu-traces.c
 create mode 100644 include/trace/events/iommu.h

-- 
1.7.10.4

[PATCH 1/7] iommu: Add event tracing feature to iommu

[Shuah Khan]

Add tracing feature to iommu to report various iommu events. Classes
iommu_group, iommu_device, and iommu_map_unmap are defined.

iommu_group class events can be enabled to trigger when devices get added
to and removed from an iommu group. Trace information includes iommu group
id and device name.

iommu:add_device_to_group
iommu:remove_device_from_group

iommu_device class events can be enabled to trigger when devices are attached
to and detached from a domain. Trace information includes device name.

iommu:attach_device_to_domain
iommu:detach_device_from_domain

iommu_map_unmap class events can be enabled to trigger when iommu map and
unmap iommu ops. Trace information includes iova, physical address (map event
only), and size.

iommu:map
iommu:unmap

Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
---
 drivers/iommu/Makefile       |    1 +
 drivers/iommu/iommu-traces.c |   24 ++++++++
 drivers/iommu/iommu.c        |    1 +
 include/trace/events/iommu.h |  129 ++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 155 insertions(+)
 create mode 100644 drivers/iommu/iommu-traces.c
 create mode 100644 include/trace/events/iommu.h

diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile
index bbe7041..9015c45 100644
--- a/drivers/iommu/Makefile
+++ b/drivers/iommu/Makefile
@@ -1,4 +1,5 @@
 obj-$(CONFIG_IOMMU_API) += iommu.o
+obj-$(CONFIG_IOMMU_API) += iommu-traces.o
 obj-$(CONFIG_OF_IOMMU)	+= of_iommu.o
 obj-$(CONFIG_MSM_IOMMU) += msm_iommu.o msm_iommu_dev.o
 obj-$(CONFIG_AMD_IOMMU) += amd_iommu.o amd_iommu_init.o
diff --git a/drivers/iommu/iommu-traces.c b/drivers/iommu/iommu-traces.c
new file mode 100644
index 0000000..a2af60f
--- /dev/null
+++ b/drivers/iommu/iommu-traces.c
@@ -0,0 +1,24 @@
+/*
+ * iommu trace points
+ *
+ * Copyright (C) 2013 Shuah Khan <shuah.kh@samsung.com>
+ *
+ */
+
+#include <linux/string.h>
+#include <linux/types.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/iommu.h>
+
+/* iommu_group_event */
+EXPORT_TRACEPOINT_SYMBOL_GPL(add_device_to_group);
+EXPORT_TRACEPOINT_SYMBOL_GPL(remove_device_from_group);
+
+/* iommu_device_event */
+EXPORT_TRACEPOINT_SYMBOL_GPL(attach_device_to_domain);
+EXPORT_TRACEPOINT_SYMBOL_GPL(detach_device_from_domain);
+
+/* iommu_map_unmap */
+EXPORT_TRACEPOINT_SYMBOL_GPL(map);
+EXPORT_TRACEPOINT_SYMBOL_GPL(unmap);
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index fbe9ca7..58f6a16 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -29,6 +29,7 @@
 #include <linux/idr.h>
 #include <linux/notifier.h>
 #include <linux/err.h>
+#include <trace/events/iommu.h>
 
 static struct kset *iommu_group_kset;
 static struct ida iommu_group_ida;
diff --git a/include/trace/events/iommu.h b/include/trace/events/iommu.h
new file mode 100644
index 0000000..86bcc5a
--- /dev/null
+++ b/include/trace/events/iommu.h
@@ -0,0 +1,129 @@
+/*
+ * iommu trace points
+ *
+ * Copyright (C) 2013 Shuah Khan <shuah.kh@samsung.com>
+ *
+ */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM iommu
+
+#if !defined(_TRACE_IOMMU_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_IOMMU_H
+
+#include <linux/tracepoint.h>
+#include <linux/pci.h>
+
+struct device;
+
+DECLARE_EVENT_CLASS(iommu_group_event,
+
+	TP_PROTO(int group_id, struct device *dev),
+
+	TP_ARGS(group_id, dev),
+
+	TP_STRUCT__entry(
+		__field(int, gid)
+		__string(device, dev_name(dev))
+	),
+
+	TP_fast_assign(
+		__entry->gid = group_id;
+		__assign_str(device, dev_name(dev));
+	),
+
+	TP_printk("IOMMU: groupID=%d device=%s",
+			__entry->gid, __get_str(device)
+	)
+);
+
+DEFINE_EVENT(iommu_group_event, add_device_to_group,
+
+	TP_PROTO(int group_id, struct device *dev),
+
+	TP_ARGS(group_id, dev)
+
+);
+
+DEFINE_EVENT(iommu_group_event, remove_device_from_group,
+
+	TP_PROTO(int group_id, struct device *dev),
+
+	TP_ARGS(group_id, dev)
+);
+
+DECLARE_EVENT_CLASS(iommu_device_event,
+
+	TP_PROTO(struct device *dev),
+
+	TP_ARGS(dev),
+
+	TP_STRUCT__entry(
+		__string(device, dev_name(dev))
+	),
+
+	TP_fast_assign(
+		__assign_str(device, dev_name(dev));
+	),
+
+	TP_printk("IOMMU: device=%s", __get_str(device)
+	)
+);
+
+DEFINE_EVENT(iommu_device_event, attach_device_to_domain,
+
+	TP_PROTO(struct device *dev),
+
+	TP_ARGS(dev)
+);
+
+DEFINE_EVENT(iommu_device_event, detach_device_from_domain,
+
+	TP_PROTO(struct device *dev),
+
+	TP_ARGS(dev)
+);
+
+DECLARE_EVENT_CLASS(iommu_map_unmap,
+
+	TP_PROTO(unsigned long iova, phys_addr_t paddr, size_t size),
+
+	TP_ARGS(iova, paddr, size),
+
+	TP_STRUCT__entry(
+		__field(u64, iova)
+		__field(u64, paddr)
+		__field(int, size)
+	),
+
+	TP_fast_assign(
+		__entry->iova = iova;
+		__entry->paddr = paddr;
+		__entry->size = size;
+	),
+
+	TP_printk("IOMMU: iova=0x%016llx paddr=0x%016llx size=0x%x",
+			__entry->iova, __entry->paddr, __entry->size
+	)
+);
+
+DEFINE_EVENT(iommu_map_unmap, map,
+
+	TP_PROTO(unsigned long iova, phys_addr_t paddr, size_t size),
+
+	TP_ARGS(iova, paddr, size)
+);
+
+DEFINE_EVENT_PRINT(iommu_map_unmap, unmap,
+
+	TP_PROTO(unsigned long iova, phys_addr_t paddr, size_t size),
+
+	TP_ARGS(iova, paddr, size),
+
+	TP_printk("IOMMU: iova=0x%016llx size=0x%x",
+			__entry->iova, __entry->size
+	)
+);
+#endif /* _TRACE_IOMMU_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
-- 
1.7.10.4

[PATCH 2/7] iommu: Change iommu driver to call add_device_to_group trace event

[Shuah Khan]

Change iommu driver to call add_device_to_group trace event. This iommu_group
class event can be enabled to trigger when devices get added to an iommu group.
Trace information includes iommu group id and device name.

Testing:
The following is trace is generated when intel-iommu driver adds devices to
to iommu groups during boot-time during its initialization:

       swapper/0-1     [003] ....     1.854793: add_device_to_group: IOMMU: groupID=0 device=0000:00:00.0
       swapper/0-1     [003] ....     1.854797: add_device_to_group: IOMMU: groupID=1 device=0000:00:02.0

Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
---
 drivers/iommu/iommu.c |    2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 58f6a16..349c92d 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -364,6 +364,8 @@ rename:
 	/* Notify any listeners about change to group. */
 	blocking_notifier_call_chain(&group->notifier,
 				     IOMMU_GROUP_NOTIFY_ADD_DEVICE, dev);
+
+	trace_add_device_to_group(group->id, dev);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(iommu_group_add_device);
-- 
1.7.10.4

[PATCH 3/7] iommu: Change iommu driver to call remove_device_to_group trace event

[Shuah Khan]

Change iommu driver to call remove_device_to_group trace event. This
iommu_group class event can be enabled to trigger when devices get
removed from an iommu group. Trace information includes iommu group id and
device name.

Testing:
Added trace calls to iommu_prepare_identity_map() for testing some of the
conditions that are hard to trigger. Here is the trace from the testing:

       swapper/0-1     [003] ....     1.854101: remove_device_from_group: IOMMU: groupID=0 device=0000:00:02.0

Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
---
 drivers/iommu/iommu.c |    2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 349c92d..278055b 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -402,6 +402,8 @@ void iommu_group_remove_device(struct device *dev)
 	sysfs_remove_link(group->devices_kobj, device->name);
 	sysfs_remove_link(&dev->kobj, "iommu_group");
 
+	trace_remove_device_from_group(group->id, dev);
+
 	kfree(device->name);
 	kfree(device);
 	dev->iommu_group = NULL;
-- 
1.7.10.4

[PATCH 4/7] iommu: Change iommu driver to call attach_device_to_domain trace event

[Shuah Khan]

Change iommu driver to call attach_device_to_domain trace event. This
iommu_device class event can be enabled to trigger when devices are attached
to a domain. Trace information includes device name.

Testing:
Added trace calls to iommu_prepare_identity_map() for testing some of the
conditions that are hard to trigger. Here is the trace from the testing:

      swapper/0-1     [003] ....     1.854102: attach_device_to_domain: IOMMU: device=0000:00:02.0

Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
---
 drivers/iommu/iommu.c |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 278055b..74c371c 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -685,10 +685,14 @@ EXPORT_SYMBOL_GPL(iommu_domain_free);
 
 int iommu_attach_device(struct iommu_domain *domain, struct device *dev)
 {
+	int ret;
 	if (unlikely(domain->ops->attach_dev == NULL))
 		return -ENODEV;
 
-	return domain->ops->attach_dev(domain, dev);
+	ret = domain->ops->attach_dev(domain, dev);
+	if (!ret)
+		trace_attach_device_to_domain(dev);
+	return ret;
 }
 EXPORT_SYMBOL_GPL(iommu_attach_device);
 
-- 
1.7.10.4

[PATCH 5/7] iommu: Change iommu driver to call detach_device_to_domain trace event

[Shuah Khan]

Change iommu driver to call detach_device_to_domain trace event. This
iommu_device class event can be enabled to trigger when devices are detached
from a domain. Trace information includes device name.

Testing:
Added trace calls to iommu_prepare_identity_map() for testing some of the
conditions that are hard to trigger. Here is the trace from the testing:

       swapper/0-1     [003] ....     1.854102: detach_device_from_domain: IOMMU: device=0000:00:02.0

Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
---
 drivers/iommu/iommu.c |    1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 74c371c..b630754 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -702,6 +702,7 @@ void iommu_detach_device(struct iommu_domain *domain, struct device *dev)
 		return;
 
 	domain->ops->detach_dev(domain, dev);
+	trace_detach_device_from_domain(dev);
 }
 EXPORT_SYMBOL_GPL(iommu_detach_device);
 
-- 
1.7.10.4

[PATCH 6/7] iommu: Change iommu driver to call map trace event

[Shuah Khan]

Change iommu driver to call map trace event. This iommu_map_unmap class event
can be enabled to trigger when iommu map iommu ops is called. Trace information
includes iova, physical address (map event only), and size.

Testing:
Added trace calls to iommu_prepare_identity_map() for testing some of the
conditions that are hard to trigger. Here is the trace from the testing:

       swapper/0-1     [003] ....     1.854102: map: IOMMU: iova=0x00000000cb800000 paddr=0x00000000cf9fffff size=0x400

Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
---
 drivers/iommu/iommu.c |    2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index b630754..ea49fe8 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -842,6 +842,8 @@ int iommu_map(struct iommu_domain *domain, unsigned long iova,
 	/* unroll mapping in case something went wrong */
 	if (ret)
 		iommu_unmap(domain, orig_iova, orig_size - size);
+	else
+		trace_map(iova, paddr, size);
 
 	return ret;
 }
-- 
1.7.10.4

[PATCH 7/7] iommu: Change iommu driver to call unmap trace event

[Shuah Khan]

Change iommu driver to call unmap trace event. This iommu_map_unmap class
event can be enabled to trigger when iommu unmap iommu ops is called. Trace
information includes iova, physical address (map event only), and size.

Testing:
Added trace calls to iommu_prepare_identity_map() for testing some of the
conditions that are hard to trigger. Here is the trace from the testing:

       swapper/0-1     [003] ....     1.854102: unmap: IOMMU: iova=0x00000000cb800000 size=0x400

Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
---
 drivers/iommu/iommu.c |    1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index ea49fe8..d8c53c7 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -892,6 +892,7 @@ size_t iommu_unmap(struct iommu_domain *domain, unsigned long iova, size_t size)
 		unmapped += unmapped_page;
 	}
 
+	trace_unmap(iova, 0, size);
 	return unmapped;
 }
 EXPORT_SYMBOL_GPL(iommu_unmap);
-- 
1.7.10.4

Re: [PATCH 0/7] iommu: Add event tracing feature to iommu

[Joerg Roedel]

On Thu, Aug 15, 2013 at 11:59:22AM -0600, Shuah Khan wrote:
> Shuah Khan (7):
>   iommu: Add event tracing feature to iommu
>   iommu: Change iommu driver to call add_device_to_group trace event
>   iommu: Change iommu driver to call remove_device_to_group trace event
>   iommu: Change iommu driver to call attach_device_to_domain trace
>     event
>   iommu: Change iommu driver to call detach_device_to_domain trace
>     event
>   iommu: Change iommu driver to call map trace event
>   iommu: Change iommu driver to call unmap trace event

Applied to tracing branch, thanks Shuah.