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: Lu 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: Joerg Roedel <jroedel@suse.de>

diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c
index cae1078cbfecbbe39a77a1ddf19663db492d76b8..d66f79acd14d0dedb231eb5076f158b9dc13b169 100644 (file)
--- a/drivers/iommu/intel/dmar.c
+++ b/drivers/iommu/intel/dmar.c
@@ -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 @@ restart:
        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;
 }