iommu/vt-d: Add qi_submit trace event

This adds a new trace event to track the submissions of requests to the
invalidation queue. This event will provide the information like:
- IOMMU name
- Invalidation type
- Descriptor raw data

A sample output like:
| qi_submit: iotlb_inv dmar1: 0x100e2 0x0 0x0 0x0
| qi_submit: dev_tlb_inv dmar1: 0x1000000003 0x7ffffffffffff001 0x0 0x0
| qi_submit: iotlb_inv dmar2: 0x800f2 0xf9a00005 0x0 0x0

This will be helpful for queued invalidation related debugging.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20210114090400.736104-1-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c
index 004feaed3c72..bd51f33642e0 100644
--- a/drivers/iommu/intel/dmar.c
+++ b/drivers/iommu/intel/dmar.c
@@ -31,6 +31,7 @@
 #include <linux/limits.h>
 #include <asm/irq_remapping.h>
 #include <asm/iommu_table.h>
+#include <trace/events/intel_iommu.h>
 
 #include "../irq_remapping.h"
 
@@ -1307,6 +1308,8 @@ restart:
 		offset = ((index + i) % QI_LENGTH) << shift;
 		memcpy(qi->desc + offset, &desc[i], 1 << shift);
 		qi->desc_status[(index + i) % QI_LENGTH] = QI_IN_USE;
+		trace_qi_submit(iommu, desc[i].qw0, desc[i].qw1,
+				desc[i].qw2, desc[i].qw3);
 	}
 	qi->desc_status[wait_index] = QI_IN_USE;