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, 119 insertions, 0 deletions

diff --git a/include/trace/events/mlxsw.h b/include/trace/events/mlxsw.h
new file mode 100644
index 000000000..19a25ed32
--- /dev/null
+++ b/include/trace/events/mlxsw.h
@@ -0,0 +1,119 @@
+/* SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0 */
+/* Copyright (c) 2019 Mellanox Technologies. All rights reserved */
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM mlxsw
+
+#if !defined(_MLXSW_TRACEPOINT_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _MLXSW_TRACEPOINT_H
+
+#include <linux/tracepoint.h>
+
+struct mlxsw_sp;
+struct mlxsw_sp_acl_atcam_region;
+struct mlxsw_sp_acl_tcam_vregion;
+
+TRACE_EVENT(mlxsw_sp_acl_atcam_entry_add_ctcam_spill,
+	TP_PROTO(const struct mlxsw_sp *mlxsw_sp,
+		 const struct mlxsw_sp_acl_atcam_region *aregion),
+
+	TP_ARGS(mlxsw_sp, aregion),
+
+	TP_STRUCT__entry(
+		__field(const void *, mlxsw_sp)
+		__field(const void *, aregion)
+	),
+
+	TP_fast_assign(
+		__entry->mlxsw_sp = mlxsw_sp;
+		__entry->aregion = aregion;
+	),
+
+	TP_printk("mlxsw_sp %p, aregion %p",
+		  __entry->mlxsw_sp, __entry->aregion)
+);
+
+TRACE_EVENT(mlxsw_sp_acl_tcam_vregion_rehash,
+	TP_PROTO(const struct mlxsw_sp *mlxsw_sp,
+		 const struct mlxsw_sp_acl_tcam_vregion *vregion),
+
+	TP_ARGS(mlxsw_sp, vregion),
+
+	TP_STRUCT__entry(
+		__field(const void *, mlxsw_sp)
+		__field(const void *, vregion)
+	),
+
+	TP_fast_assign(
+		__entry->mlxsw_sp = mlxsw_sp;
+		__entry->vregion = vregion;
+	),
+
+	TP_printk("mlxsw_sp %p, vregion %p",
+		  __entry->mlxsw_sp, __entry->vregion)
+);
+
+TRACE_EVENT(mlxsw_sp_acl_tcam_vregion_migrate,
+	TP_PROTO(const struct mlxsw_sp *mlxsw_sp,
+		 const struct mlxsw_sp_acl_tcam_vregion *vregion),
+
+	TP_ARGS(mlxsw_sp, vregion),
+
+	TP_STRUCT__entry(
+		__field(const void *, mlxsw_sp)
+		__field(const void *, vregion)
+	),
+
+	TP_fast_assign(
+		__entry->mlxsw_sp = mlxsw_sp;
+		__entry->vregion = vregion;
+	),
+
+	TP_printk("mlxsw_sp %p, vregion %p",
+		  __entry->mlxsw_sp, __entry->vregion)
+);
+
+TRACE_EVENT(mlxsw_sp_acl_tcam_vregion_migrate_end,
+	TP_PROTO(const struct mlxsw_sp *mlxsw_sp,
+		 const struct mlxsw_sp_acl_tcam_vregion *vregion),
+
+	TP_ARGS(mlxsw_sp, vregion),
+
+	TP_STRUCT__entry(
+		__field(const void *, mlxsw_sp)
+		__field(const void *, vregion)
+	),
+
+	TP_fast_assign(
+		__entry->mlxsw_sp = mlxsw_sp;
+		__entry->vregion = vregion;
+	),
+
+	TP_printk("mlxsw_sp %p, vregion %p",
+		  __entry->mlxsw_sp, __entry->vregion)
+);
+
+TRACE_EVENT(mlxsw_sp_acl_tcam_vregion_rehash_rollback_failed,
+	TP_PROTO(const struct mlxsw_sp *mlxsw_sp,
+		 const struct mlxsw_sp_acl_tcam_vregion *vregion),
+
+	TP_ARGS(mlxsw_sp, vregion),
+
+	TP_STRUCT__entry(
+		__field(const void *, mlxsw_sp)
+		__field(const void *, vregion)
+	),
+
+	TP_fast_assign(
+		__entry->mlxsw_sp = mlxsw_sp;
+		__entry->vregion = vregion;
+	),
+
+	TP_printk("mlxsw_sp %p, vregion %p",
+		  __entry->mlxsw_sp, __entry->vregion)
+);
+
+#endif /* _MLXSW_TRACEPOINT_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>