Commit 74eb87a0 authored by Lu Baolu's avatar Lu Baolu Committed by Joerg Roedel
Browse files

iommu/vt-d: Add cache invalidation latency sampling 



Queued invalidation execution time is performance critical and needs
to be monitored. This adds code to sample the execution time of IOTLB/
devTLB/ICE cache invalidation.

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/20210610020115.1637656-16-baolu.lu@linux.intel.com


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent 456bb0b9

drivers/iommu/intel/dmar.c

+31 −0
Original line number Diff line number Diff line
@@ -34,6 +34,7 @@ 
#include <trace/events/intel_iommu.h>



#include "../irq_remapping.h"

#include "perf.h"



typedef int (*dmar_res_handler_t)(struct acpi_dmar_header *, void *);

struct dmar_res_callback {
@@ -1342,15 +1343,33 @@ int qi_submit_sync(struct intel_iommu *iommu, struct qi_desc *desc, 
		   unsigned int count, unsigned long options)

{

	struct q_inval *qi = iommu->qi;

	s64 devtlb_start_ktime = 0;

	s64 iotlb_start_ktime = 0;

	s64 iec_start_ktime = 0;

	struct qi_desc wait_desc;

	int wait_index, index;

	unsigned long flags;

	int offset, shift;

	int rc, i;

	u64 type;



	if (!qi)

		return 0;



	type = desc->qw0 & GENMASK_ULL(3, 0);



	if ((type == QI_IOTLB_TYPE || type == QI_EIOTLB_TYPE) &&

	    dmar_latency_enabled(iommu, DMAR_LATENCY_INV_IOTLB))

		iotlb_start_ktime = ktime_to_ns(ktime_get());



	if ((type == QI_DIOTLB_TYPE || type == QI_DEIOTLB_TYPE) &&

	    dmar_latency_enabled(iommu, DMAR_LATENCY_INV_DEVTLB))

		devtlb_start_ktime = ktime_to_ns(ktime_get());



	if (type == QI_IEC_TYPE &&

	    dmar_latency_enabled(iommu, DMAR_LATENCY_INV_IEC))

		iec_start_ktime = ktime_to_ns(ktime_get());



restart:

	rc = 0;
@@ -1425,6 +1444,18 @@ int qi_submit_sync(struct intel_iommu *iommu, struct qi_desc *desc, 
	if (rc == -EAGAIN)

		goto restart;



	if (iotlb_start_ktime)

		dmar_latency_update(iommu, DMAR_LATENCY_INV_IOTLB,

				ktime_to_ns(ktime_get()) - iotlb_start_ktime);



	if (devtlb_start_ktime)

		dmar_latency_update(iommu, DMAR_LATENCY_INV_DEVTLB,

				ktime_to_ns(ktime_get()) - devtlb_start_ktime);



	if (iec_start_ktime)

		dmar_latency_update(iommu, DMAR_LATENCY_INV_IEC,

				ktime_to_ns(ktime_get()) - iec_start_ktime);



	return rc;

}