KVM: Don't pre-reserve xarray entries when storing empty/NULL attributesgrafted

Skip the xarray reservation loop when clearing all memory attributes, as
storing NULL only erases the entry and never needs to allocate, so no
reservation (and no cleanup of a failed one) is required in that case.

Suggested-by: Sean Christopherson <seanjc@google.com>
Cc: David Ballesteros <davimaba.v@proton.me>
Signed-off-by: Zeng Chi <zengchi@kylinos.cn>
Link: https://patch.msgid.link/20260921102442.1232375-1-zeng_chi911@163.com
[sean: split to separate patch]
Signed-off-by: Sean Christopherson <seanjc@google.com>

1 files changed, 189 insertions, 0 deletions

diff --git a/drivers/iommu/intel/trace.h b/drivers/iommu/intel/trace.h
new file mode 100644
index 000000000..9f0ab4353
--- /dev/null
+++ b/drivers/iommu/intel/trace.h
@@ -0,0 +1,189 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Intel IOMMU trace support
+ *
+ * Copyright (C) 2019 Intel Corporation
+ *
+ * Author: Lu Baolu <baolu.lu@linux.intel.com>
+ */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM intel_iommu
+
+#if !defined(_TRACE_INTEL_IOMMU_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_INTEL_IOMMU_H
+
+#include <linux/tracepoint.h>
+
+#include "iommu.h"
+
+#define MSG_MAX		256
+
+TRACE_EVENT(qi_submit,
+	TP_PROTO(struct intel_iommu *iommu, u64 qw0, u64 qw1, u64 qw2, u64 qw3),
+
+	TP_ARGS(iommu, qw0, qw1, qw2, qw3),
+
+	TP_STRUCT__entry(
+		__field(u64, qw0)
+		__field(u64, qw1)
+		__field(u64, qw2)
+		__field(u64, qw3)
+		__string(iommu, iommu->name)
+	),
+
+	TP_fast_assign(
+		__assign_str(iommu);
+		__entry->qw0 = qw0;
+		__entry->qw1 = qw1;
+		__entry->qw2 = qw2;
+		__entry->qw3 = qw3;
+	),
+
+	TP_printk("%s %s: 0x%llx 0x%llx 0x%llx 0x%llx",
+		  __print_symbolic(__entry->qw0 & 0xf,
+				   { QI_CC_TYPE,	"cc_inv" },
+				   { QI_IOTLB_TYPE,	"iotlb_inv" },
+				   { QI_DIOTLB_TYPE,	"dev_tlb_inv" },
+				   { QI_IEC_TYPE,	"iec_inv" },
+				   { QI_IWD_TYPE,	"inv_wait" },
+				   { QI_EIOTLB_TYPE,	"p_iotlb_inv" },
+				   { QI_PC_TYPE,	"pc_inv" },
+				   { QI_DEIOTLB_TYPE,	"p_dev_tlb_inv" },
+				   { QI_PGRP_RESP_TYPE,	"page_grp_resp" }),
+		__get_str(iommu),
+		__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);
+		__assign_str(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)
+	)
+);
+
+DECLARE_EVENT_CLASS(cache_tag_log,
+	TP_PROTO(struct cache_tag *tag),
+	TP_ARGS(tag),
+	TP_STRUCT__entry(
+		__string(iommu, tag->iommu->name)
+		__string(dev, dev_name(tag->dev))
+		__field(u16, type)
+		__field(u16, domain_id)
+		__field(u32, pasid)
+		__field(u32, users)
+	),
+	TP_fast_assign(
+		__assign_str(iommu);
+		__assign_str(dev);
+		__entry->type = tag->type;
+		__entry->domain_id = tag->domain_id;
+		__entry->pasid = tag->pasid;
+		__entry->users = tag->users;
+	),
+	TP_printk("%s/%s type %s did %d pasid %d ref %d",
+		  __get_str(iommu), __get_str(dev),
+		  __print_symbolic(__entry->type,
+			{ CACHE_TAG_IOTLB,		"iotlb" },
+			{ CACHE_TAG_DEVTLB,		"devtlb" },
+			{ CACHE_TAG_NESTING_IOTLB,	"nesting_iotlb" },
+			{ CACHE_TAG_NESTING_DEVTLB,	"nesting_devtlb" }),
+		__entry->domain_id, __entry->pasid, __entry->users
+	)
+);
+
+DEFINE_EVENT(cache_tag_log, cache_tag_assign,
+	TP_PROTO(struct cache_tag *tag),
+	TP_ARGS(tag)
+);
+
+DEFINE_EVENT(cache_tag_log, cache_tag_unassign,
+	TP_PROTO(struct cache_tag *tag),
+	TP_ARGS(tag)
+);
+
+DECLARE_EVENT_CLASS(cache_tag_flush,
+	TP_PROTO(struct cache_tag *tag, unsigned long start, unsigned long end,
+		 unsigned long addr, unsigned long mask),
+	TP_ARGS(tag, start, end, addr, mask),
+	TP_STRUCT__entry(
+		__string(iommu, tag->iommu->name)
+		__string(dev, dev_name(tag->dev))
+		__field(u16, type)
+		__field(u16, domain_id)
+		__field(u32, pasid)
+		__field(unsigned long, start)
+		__field(unsigned long, end)
+		__field(unsigned long, addr)
+		__field(unsigned long, mask)
+	),
+	TP_fast_assign(
+		__assign_str(iommu);
+		__assign_str(dev);
+		__entry->type = tag->type;
+		__entry->domain_id = tag->domain_id;
+		__entry->pasid = tag->pasid;
+		__entry->start = start;
+		__entry->end = end;
+		__entry->addr = addr;
+		__entry->mask = mask;
+	),
+	TP_printk("%s %s[%d] type %s did %d [0x%lx-0x%lx] addr 0x%lx mask 0x%lx",
+		  __get_str(iommu), __get_str(dev), __entry->pasid,
+		  __print_symbolic(__entry->type,
+			{ CACHE_TAG_IOTLB,		"iotlb" },
+			{ CACHE_TAG_DEVTLB,		"devtlb" },
+			{ CACHE_TAG_NESTING_IOTLB,	"nesting_iotlb" },
+			{ CACHE_TAG_NESTING_DEVTLB,	"nesting_devtlb" }),
+		__entry->domain_id, __entry->start, __entry->end,
+		__entry->addr, __entry->mask
+	)
+);
+
+DEFINE_EVENT(cache_tag_flush, cache_tag_flush_range,
+	TP_PROTO(struct cache_tag *tag, unsigned long start, unsigned long end,
+		 unsigned long addr, unsigned long mask),
+	TP_ARGS(tag, start, end, addr, mask)
+);
+
+DEFINE_EVENT(cache_tag_flush, cache_tag_flush_range_np,
+	TP_PROTO(struct cache_tag *tag, unsigned long start, unsigned long end,
+		 unsigned long addr, unsigned long mask),
+	TP_ARGS(tag, start, end, addr, mask)
+);
+#endif /* _TRACE_INTEL_IOMMU_H */
+
+/* This part must be outside protection */
+#undef TRACE_INCLUDE_PATH
+#undef TRACE_INCLUDE_FILE
+#define TRACE_INCLUDE_PATH ../../drivers/iommu/intel/
+#define TRACE_INCLUDE_FILE trace
+#include <trace/define_trace.h>