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, 245 insertions, 0 deletions

diff --git a/include/trace/events/fsi.h b/include/trace/events/fsi.h
new file mode 100644
index 000000000..5ff15126a
--- /dev/null
+++ b/include/trace/events/fsi.h
@@ -0,0 +1,245 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM fsi
+
+#if !defined(_TRACE_FSI_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_FSI_H
+
+#include <linux/tracepoint.h>
+
+TRACE_EVENT(fsi_master_read,
+	TP_PROTO(const struct fsi_master *master, int link, int id,
+			uint32_t addr, size_t size),
+	TP_ARGS(master, link, id, addr, size),
+	TP_STRUCT__entry(
+		__field(int,	master_idx)
+		__field(int,	link)
+		__field(int,	id)
+		__field(__u32,	addr)
+		__field(size_t,	size)
+	),
+	TP_fast_assign(
+		__entry->master_idx = master->idx;
+		__entry->link = link;
+		__entry->id = id;
+		__entry->addr = addr;
+		__entry->size = size;
+	),
+	TP_printk("fsi%d:%02d:%02d %08x[%zu]",
+		__entry->master_idx,
+		__entry->link,
+		__entry->id,
+		__entry->addr,
+		__entry->size
+	)
+);
+
+TRACE_EVENT(fsi_master_write,
+	TP_PROTO(const struct fsi_master *master, int link, int id,
+			uint32_t addr, size_t size, const void *data),
+	TP_ARGS(master, link, id, addr, size, data),
+	TP_STRUCT__entry(
+		__field(int,	master_idx)
+		__field(int,	link)
+		__field(int,	id)
+		__field(__u32,	addr)
+		__field(size_t,	size)
+		__field(__u32,	data)
+	),
+	TP_fast_assign(
+		__entry->master_idx = master->idx;
+		__entry->link = link;
+		__entry->id = id;
+		__entry->addr = addr;
+		__entry->size = size;
+		__entry->data = 0;
+		memcpy(&__entry->data, data, size);
+	),
+	TP_printk("fsi%d:%02d:%02d %08x[%zu] <= {%*ph}",
+		__entry->master_idx,
+		__entry->link,
+		__entry->id,
+		__entry->addr,
+		__entry->size,
+		(int)__entry->size, &__entry->data
+	)
+);
+
+TRACE_EVENT(fsi_master_rw_result,
+	TP_PROTO(const struct fsi_master *master, int link, int id,
+			uint32_t addr, size_t size,
+			bool write, const void *data, int ret),
+	TP_ARGS(master, link, id, addr, size, write, data, ret),
+	TP_STRUCT__entry(
+		__field(int,	master_idx)
+		__field(int,	link)
+		__field(int,	id)
+		__field(__u32,	addr)
+		__field(size_t,	size)
+		__field(bool,	write)
+		__field(__u32,	data)
+		__field(int,	ret)
+	),
+	TP_fast_assign(
+		__entry->master_idx = master->idx;
+		__entry->link = link;
+		__entry->id = id;
+		__entry->addr = addr;
+		__entry->size = size;
+		__entry->write = write;
+		__entry->data = 0;
+		__entry->ret = ret;
+		if (__entry->write || !__entry->ret)
+			memcpy(&__entry->data, data, size);
+	),
+	TP_printk("fsi%d:%02d:%02d %08x[%zu] %s {%*ph} ret %d",
+		__entry->master_idx,
+		__entry->link,
+		__entry->id,
+		__entry->addr,
+		__entry->size,
+		__entry->write ? "<=" : "=>",
+		(int)__entry->size, &__entry->data,
+		__entry->ret
+	)
+);
+
+TRACE_EVENT(fsi_master_break,
+	TP_PROTO(const struct fsi_master *master, int link),
+	TP_ARGS(master, link),
+	TP_STRUCT__entry(
+		__field(int,	master_idx)
+		__field(int,	link)
+	),
+	TP_fast_assign(
+		__entry->master_idx = master->idx;
+		__entry->link = link;
+	),
+	TP_printk("fsi%d:%d",
+		__entry->master_idx,
+		__entry->link
+	)
+);
+
+TRACE_EVENT(fsi_master_scan,
+	TP_PROTO(const struct fsi_master *master, bool scan),
+	TP_ARGS(master, scan),
+	TP_STRUCT__entry(
+		__field(int,	master_idx)
+		__field(int,	n_links)
+		__field(bool,	scan)
+	),
+	TP_fast_assign(
+		__entry->master_idx = master->idx;
+		__entry->n_links = master->n_links;
+		__entry->scan = scan;
+	),
+	TP_printk("fsi%d (%d links) %s", __entry->master_idx, __entry->n_links,
+		  __entry->scan ? "scan" : "unscan")
+);
+
+TRACE_EVENT(fsi_master_unregister,
+	TP_PROTO(const struct fsi_master *master),
+	TP_ARGS(master),
+	TP_STRUCT__entry(
+		__field(int,	master_idx)
+		__field(int,	n_links)
+	),
+	TP_fast_assign(
+		__entry->master_idx = master->idx;
+		__entry->n_links = master->n_links;
+	),
+	TP_printk("fsi%d (%d links)", __entry->master_idx, __entry->n_links)
+);
+
+TRACE_EVENT(fsi_slave_init,
+	TP_PROTO(const struct fsi_slave *slave),
+	TP_ARGS(slave),
+	TP_STRUCT__entry(
+		__field(int,	master_idx)
+		__field(int,	master_n_links)
+		__field(int,	idx)
+		__field(int,	link)
+		__field(int,	chip_id)
+		__field(__u32,	cfam_id)
+		__field(__u32,	size)
+	),
+	TP_fast_assign(
+		__entry->master_idx = slave->master->idx;
+		__entry->master_n_links = slave->master->n_links;
+		__entry->idx = slave->cdev_idx;
+		__entry->link = slave->link;
+		__entry->chip_id = slave->chip_id;
+		__entry->cfam_id = slave->cfam_id;
+		__entry->size = slave->size;
+	),
+	TP_printk("fsi%d: idx:%d link:%d/%d cid:%d cfam:%08x %08x",
+		__entry->master_idx,
+		__entry->idx,
+		__entry->link,
+		__entry->master_n_links,
+		__entry->chip_id,
+		__entry->cfam_id,
+		__entry->size
+	)
+);
+
+TRACE_EVENT(fsi_slave_invalid_cfam,
+	TP_PROTO(const struct fsi_master *master, int link, uint32_t cfam_id),
+	TP_ARGS(master, link, cfam_id),
+	TP_STRUCT__entry(
+		__field(int,	master_idx)
+		__field(int,	master_n_links)
+		__field(int,	link)
+		__field(__u32,	cfam_id)
+	),
+	TP_fast_assign(
+		__entry->master_idx = master->idx;
+		__entry->master_n_links = master->n_links;
+		__entry->link = link;
+		__entry->cfam_id = cfam_id;
+	),
+	TP_printk("fsi%d: cfam:%08x link:%d/%d",
+		__entry->master_idx,
+		__entry->cfam_id,
+		__entry->link,
+		__entry->master_n_links
+	)
+);
+
+TRACE_EVENT(fsi_dev_init,
+	TP_PROTO(const struct fsi_device *dev),
+	TP_ARGS(dev),
+	TP_STRUCT__entry(
+		__field(int,	master_idx)
+		__field(int,	link)
+		__field(int,	type)
+		__field(int,	unit)
+		__field(int,	version)
+		__field(__u32,	addr)
+		__field(__u32,	size)
+	),
+	TP_fast_assign(
+		__entry->master_idx = dev->slave->master->idx;
+		__entry->link = dev->slave->link;
+		__entry->type = dev->engine_type;
+		__entry->unit = dev->unit;
+		__entry->version = dev->version;
+		__entry->addr = dev->addr;
+		__entry->size = dev->size;
+	),
+	TP_printk("fsi%d: slv%d: t:%02x u:%02x v:%02x %08x@%08x",
+		__entry->master_idx,
+		__entry->link,
+		__entry->type,
+		__entry->unit,
+		__entry->version,
+		__entry->size,
+		__entry->addr
+	)
+);
+
+#endif /* _TRACE_FSI_H */
+
+#include <trace/define_trace.h>