Commit e93a67f5 authored by Lu Baolu's avatar Lu Baolu Committed by Joerg Roedel
Browse files

iommu/vt-d: Add prq_report trace event 



This adds a new trace event to track the page fault request report.
This event will provide almost all information defined in a page
request descriptor.

A sample output:
| prq_report: dmar0/0000:00:0a.0 seq# 1: rid=0x50 addr=0x559ef6f97 r---- pasid=0x2 index=0x1
| prq_report: dmar0/0000:00:0a.0 seq# 2: rid=0x50 addr=0x559ef6f9c rw--l pasid=0x2 index=0x1
| prq_report: dmar0/0000:00:0a.0 seq# 3: rid=0x50 addr=0x559ef6f98 r---- pasid=0x2 index=0x1
| prq_report: dmar0/0000:00:0a.0 seq# 4: rid=0x50 addr=0x559ef6f9d rw--l pasid=0x2 index=0x1
| prq_report: dmar0/0000:00:0a.0 seq# 5: rid=0x50 addr=0x559ef6f99 r---- pasid=0x2 index=0x1
| prq_report: dmar0/0000:00:0a.0 seq# 6: rid=0x50 addr=0x559ef6f9e rw--l pasid=0x2 index=0x1
| prq_report: dmar0/0000:00:0a.0 seq# 7: rid=0x50 addr=0x559ef6f9a r---- pasid=0x2 index=0x1
| prq_report: dmar0/0000:00:0a.0 seq# 8: rid=0x50 addr=0x559ef6f9f rw--l pasid=0x2 index=0x1

This will be helpful for I/O page fault related debugging.

Signed-off-by: default avatarLu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20210520031531.712333-1-baolu.lu@linux.intel.com
Link: https://lore.kernel.org/r/20210610020115.1637656-13-baolu.lu@linux.intel.com


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent d5b9e4bf

drivers/iommu/intel/svm.c

+7 −0
Original line number Diff line number Diff line
@@ -21,6 +21,7 @@ 
#include <linux/ioasid.h>

#include <asm/page.h>

#include <asm/fpu/api.h>

#include <trace/events/intel_iommu.h>



#include "pasid.h"

#include "../iommu-sva-lib.h"
@@ -976,12 +977,18 @@ static irqreturn_t prq_event_thread(int irq, void *d) 
				goto bad_req;

		}



		sdev->prq_seq_number++;



		/*

		 * If prq is to be handled outside iommu driver via receiver of

		 * the fault notifiers, we skip the page response here.

		 */

		if (intel_svm_prq_report(sdev->dev, req))

			handle_bad_prq_event(iommu, req, QI_RESP_INVALID);



		trace_prq_report(iommu, sdev->dev, req->qw_0, req->qw_1,

				 req->priv_data[0], req->priv_data[1],

				 sdev->prq_seq_number);

prq_advance:

		head = (head + sizeof(*req)) & PRQ_RING_MASK;

	}

include/linux/intel-iommu.h

+29 −0
Original line number Diff line number Diff line
@@ -778,6 +778,7 @@ struct intel_svm_dev { 
	struct device *dev;

	struct intel_iommu *iommu;

	struct iommu_sva sva;

	unsigned long prq_seq_number;

	u32 pasid;

	int users;

	u16 did;
@@ -828,4 +829,32 @@ static inline int iommu_calculate_max_sagaw(struct intel_iommu *iommu) 
#define intel_iommu_enabled (0)

#endif



static inline const char *decode_prq_descriptor(char *str, size_t size,

		u64 dw0, u64 dw1, u64 dw2, u64 dw3)

{

	char *buf = str;

	int bytes;



	bytes = snprintf(buf, size,

			 "rid=0x%llx addr=0x%llx %c%c%c%c%c pasid=0x%llx index=0x%llx",

			 FIELD_GET(GENMASK_ULL(31, 16), dw0),

			 FIELD_GET(GENMASK_ULL(63, 12), dw1),

			 dw1 & BIT_ULL(0) ? 'r' : '-',

			 dw1 & BIT_ULL(1) ? 'w' : '-',

			 dw0 & BIT_ULL(52) ? 'x' : '-',

			 dw0 & BIT_ULL(53) ? 'p' : '-',

			 dw1 & BIT_ULL(2) ? 'l' : '-',

			 FIELD_GET(GENMASK_ULL(51, 32), dw0),

			 FIELD_GET(GENMASK_ULL(11, 3), dw1));



	/* Private Data */

	if (dw0 & BIT_ULL(9)) {

		size -= bytes;

		buf += bytes;

		snprintf(buf, size, " private=0x%llx/0x%llx\n", dw2, dw3);

	}



	return str;

}



#endif

include/trace/events/intel_iommu.h

+37 −0
Original line number Diff line number Diff line
@@ -15,6 +15,8 @@ 
#include <linux/tracepoint.h>

#include <linux/intel-iommu.h>



#define MSG_MAX		256



TRACE_EVENT(qi_submit,

	TP_PROTO(struct intel_iommu *iommu, u64 qw0, u64 qw1, u64 qw2, u64 qw3),
@@ -51,6 +53,41 @@ TRACE_EVENT(qi_submit, 
		__entry->qw0, __entry->qw1, __entry->qw2, __entry->qw3

	)

);



TRACE_EVENT(prq_report,

	TP_PROTO(struct intel_iommu *iommu, struct device *dev,

		 u64 dw0, u64 dw1, u64 dw2, u64 dw3,

		 unsigned long seq),



	TP_ARGS(iommu, dev, dw0, dw1, dw2, dw3, seq),



	TP_STRUCT__entry(

		__field(u64, dw0)

		__field(u64, dw1)

		__field(u64, dw2)

		__field(u64, dw3)

		__field(unsigned long, seq)

		__string(iommu, iommu->name)

		__string(dev, dev_name(dev))

		__dynamic_array(char, buff, MSG_MAX)

	),



	TP_fast_assign(

		__entry->dw0 = dw0;

		__entry->dw1 = dw1;

		__entry->dw2 = dw2;

		__entry->dw3 = dw3;

		__entry->seq = seq;

		__assign_str(iommu, iommu->name);

		__assign_str(dev, dev_name(dev));

	),



	TP_printk("%s/%s seq# %ld: %s",

		__get_str(iommu), __get_str(dev), __entry->seq,

		decode_prq_descriptor(__get_str(buff), MSG_MAX, __entry->dw0,

				      __entry->dw1, __entry->dw2, __entry->dw3)

	)

);

#endif /* _TRACE_INTEL_IOMMU_H */



/* This part must be outside protection */