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, 268 insertions, 0 deletions

diff --git a/include/trace/events/v4l2.h b/include/trace/events/v4l2.h
new file mode 100644
index 000000000..248bc09bf
--- /dev/null
+++ b/include/trace/events/v4l2.h
@@ -0,0 +1,268 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM v4l2
+
+#if !defined(_TRACE_V4L2_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_V4L2_H
+
+#include <linux/tracepoint.h>
+#include <media/videobuf2-v4l2.h>
+
+/* Enums require being exported to userspace, for user tool parsing */
+#undef EM
+#undef EMe
+#define EM(a, b)	TRACE_DEFINE_ENUM(a);
+#define EMe(a, b)	TRACE_DEFINE_ENUM(a);
+
+#define show_type(type)							\
+	__print_symbolic(type, SHOW_TYPE)
+
+#define SHOW_TYPE							\
+	EM( V4L2_BUF_TYPE_VIDEO_CAPTURE,	"VIDEO_CAPTURE" )	\
+	EM( V4L2_BUF_TYPE_VIDEO_OUTPUT,		"VIDEO_OUTPUT" )	\
+	EM( V4L2_BUF_TYPE_VIDEO_OVERLAY,	"VIDEO_OVERLAY" )	\
+	EM( V4L2_BUF_TYPE_VBI_CAPTURE,		"VBI_CAPTURE" )		\
+	EM( V4L2_BUF_TYPE_VBI_OUTPUT,		"VBI_OUTPUT" )		\
+	EM( V4L2_BUF_TYPE_SLICED_VBI_CAPTURE,   "SLICED_VBI_CAPTURE" )	\
+	EM( V4L2_BUF_TYPE_SLICED_VBI_OUTPUT,    "SLICED_VBI_OUTPUT" )	\
+	EM( V4L2_BUF_TYPE_VIDEO_OUTPUT_OVERLAY, "VIDEO_OUTPUT_OVERLAY" ) \
+	EM( V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE, "VIDEO_CAPTURE_MPLANE" ) \
+	EM( V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE,  "VIDEO_OUTPUT_MPLANE" )	\
+	EM( V4L2_BUF_TYPE_SDR_CAPTURE,          "SDR_CAPTURE" )		\
+	EM( V4L2_BUF_TYPE_SDR_OUTPUT,           "SDR_OUTPUT" )		\
+	EM( V4L2_BUF_TYPE_META_CAPTURE,		"META_CAPTURE" )	\
+	EMe(V4L2_BUF_TYPE_PRIVATE,		"PRIVATE" )
+
+SHOW_TYPE
+
+#define show_field(field)						\
+	__print_symbolic(field, SHOW_FIELD)
+
+#define SHOW_FIELD							\
+	EM( V4L2_FIELD_ANY,		"ANY" )				\
+	EM( V4L2_FIELD_NONE,		"NONE" )			\
+	EM( V4L2_FIELD_TOP,		"TOP" )				\
+	EM( V4L2_FIELD_BOTTOM,		"BOTTOM" )			\
+	EM( V4L2_FIELD_INTERLACED,	"INTERLACED" )			\
+	EM( V4L2_FIELD_SEQ_TB,		"SEQ_TB" )			\
+	EM( V4L2_FIELD_SEQ_BT,		"SEQ_BT" )			\
+	EM( V4L2_FIELD_ALTERNATE,	"ALTERNATE" )			\
+	EM( V4L2_FIELD_INTERLACED_TB,	"INTERLACED_TB" )		\
+	EMe( V4L2_FIELD_INTERLACED_BT,	"INTERLACED_BT" )
+
+SHOW_FIELD
+
+/*
+ * Now redefine the EM() and EMe() macros to map the enums to the strings
+ * that will be printed in the output.
+ */
+#undef EM
+#undef EMe
+#define EM(a, b)	{a, b},
+#define EMe(a, b)	{a, b}
+
+/* V4L2_TC_TYPE_* are macros, not defines, they do not need processing */
+
+#define show_timecode_type(type)					\
+	__print_symbolic(type,						\
+		{ V4L2_TC_TYPE_24FPS,		"24FPS" },		\
+		{ V4L2_TC_TYPE_25FPS,		"25FPS" },		\
+		{ V4L2_TC_TYPE_30FPS,		"30FPS" },		\
+		{ V4L2_TC_TYPE_50FPS,		"50FPS" },		\
+		{ V4L2_TC_TYPE_60FPS,		"60FPS" })
+
+#define show_flags(flags)						      \
+	__print_flags(flags, "|",					      \
+		{ V4L2_BUF_FLAG_MAPPED,		     "MAPPED" },	      \
+		{ V4L2_BUF_FLAG_QUEUED,		     "QUEUED" },	      \
+		{ V4L2_BUF_FLAG_DONE,		     "DONE" },		      \
+		{ V4L2_BUF_FLAG_KEYFRAME,	     "KEYFRAME" },	      \
+		{ V4L2_BUF_FLAG_PFRAME,		     "PFRAME" },	      \
+		{ V4L2_BUF_FLAG_BFRAME,		     "BFRAME" },	      \
+		{ V4L2_BUF_FLAG_ERROR,		     "ERROR" },		      \
+		{ V4L2_BUF_FLAG_TIMECODE,	     "TIMECODE" },	      \
+		{ V4L2_BUF_FLAG_PREPARED,	     "PREPARED" },	      \
+		{ V4L2_BUF_FLAG_NO_CACHE_INVALIDATE, "NO_CACHE_INVALIDATE" }, \
+		{ V4L2_BUF_FLAG_NO_CACHE_CLEAN,	     "NO_CACHE_CLEAN" },      \
+		{ V4L2_BUF_FLAG_TIMESTAMP_MASK,	     "TIMESTAMP_MASK" },      \
+		{ V4L2_BUF_FLAG_TIMESTAMP_UNKNOWN,   "TIMESTAMP_UNKNOWN" },   \
+		{ V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC, "TIMESTAMP_MONOTONIC" }, \
+		{ V4L2_BUF_FLAG_TIMESTAMP_COPY,	     "TIMESTAMP_COPY" },      \
+		{ V4L2_BUF_FLAG_LAST,                "LAST" })
+
+#define show_timecode_flags(flags)					  \
+	__print_flags(flags, "|",					  \
+		{ V4L2_TC_FLAG_DROPFRAME,       "DROPFRAME" },		  \
+		{ V4L2_TC_FLAG_COLORFRAME,      "COLORFRAME" },		  \
+		{ V4L2_TC_USERBITS_USERDEFINED,	"USERBITS_USERDEFINED" }, \
+		{ V4L2_TC_USERBITS_8BITCHARS,	"USERBITS_8BITCHARS" })
+
+DECLARE_EVENT_CLASS(v4l2_event_class,
+	TP_PROTO(int minor, struct v4l2_buffer *buf),
+
+	TP_ARGS(minor, buf),
+
+	TP_STRUCT__entry(
+		__field(int, minor)
+		__field(u32, index)
+		__field(u32, type)
+		__field(u32, bytesused)
+		__field(u32, flags)
+		__field(u32, field)
+		__field(s64, timestamp)
+		__field(u32, timecode_type)
+		__field(u32, timecode_flags)
+		__field(u8, timecode_frames)
+		__field(u8, timecode_seconds)
+		__field(u8, timecode_minutes)
+		__field(u8, timecode_hours)
+		__field(u8, timecode_userbits0)
+		__field(u8, timecode_userbits1)
+		__field(u8, timecode_userbits2)
+		__field(u8, timecode_userbits3)
+		__field(u32, sequence)
+	),
+
+	TP_fast_assign(
+		__entry->minor = minor;
+		__entry->index = buf->index;
+		__entry->type = buf->type;
+		__entry->bytesused = buf->bytesused;
+		__entry->flags = buf->flags;
+		__entry->field = buf->field;
+		__entry->timestamp = v4l2_buffer_get_timestamp(buf);
+		__entry->timecode_type = buf->timecode.type;
+		__entry->timecode_flags = buf->timecode.flags;
+		__entry->timecode_frames = buf->timecode.frames;
+		__entry->timecode_seconds = buf->timecode.seconds;
+		__entry->timecode_minutes = buf->timecode.minutes;
+		__entry->timecode_hours = buf->timecode.hours;
+		__entry->timecode_userbits0 = buf->timecode.userbits[0];
+		__entry->timecode_userbits1 = buf->timecode.userbits[1];
+		__entry->timecode_userbits2 = buf->timecode.userbits[2];
+		__entry->timecode_userbits3 = buf->timecode.userbits[3];
+		__entry->sequence = buf->sequence;
+	),
+
+	TP_printk("minor = %d, index = %u, type = %s, bytesused = %u, "
+		  "flags = %s, field = %s, timestamp = %llu, "
+		  "timecode = { type = %s, flags = %s, frames = %u, "
+		  "seconds = %u, minutes = %u, hours = %u, "
+		  "userbits = { %u %u %u %u } }, sequence = %u", __entry->minor,
+		  __entry->index, show_type(__entry->type),
+		  __entry->bytesused,
+		  show_flags(__entry->flags),
+		  show_field(__entry->field),
+		  __entry->timestamp,
+		  show_timecode_type(__entry->timecode_type),
+		  show_timecode_flags(__entry->timecode_flags),
+		  __entry->timecode_frames,
+		  __entry->timecode_seconds,
+		  __entry->timecode_minutes,
+		  __entry->timecode_hours,
+		  __entry->timecode_userbits0,
+		  __entry->timecode_userbits1,
+		  __entry->timecode_userbits2,
+		  __entry->timecode_userbits3,
+		  __entry->sequence
+	)
+)
+
+DEFINE_EVENT(v4l2_event_class, v4l2_dqbuf,
+	TP_PROTO(int minor, struct v4l2_buffer *buf),
+	TP_ARGS(minor, buf)
+);
+
+DEFINE_EVENT(v4l2_event_class, v4l2_qbuf,
+	TP_PROTO(int minor, struct v4l2_buffer *buf),
+	TP_ARGS(minor, buf)
+);
+
+DECLARE_EVENT_CLASS(vb2_v4l2_event_class,
+	TP_PROTO(struct vb2_queue *q, struct vb2_buffer *vb),
+	TP_ARGS(q, vb),
+
+	TP_STRUCT__entry(
+		__field(int, minor)
+		__field(u32, flags)
+		__field(u32, field)
+		__field(u64, timestamp)
+		__field(u32, timecode_type)
+		__field(u32, timecode_flags)
+		__field(u8, timecode_frames)
+		__field(u8, timecode_seconds)
+		__field(u8, timecode_minutes)
+		__field(u8, timecode_hours)
+		__field(u8, timecode_userbits0)
+		__field(u8, timecode_userbits1)
+		__field(u8, timecode_userbits2)
+		__field(u8, timecode_userbits3)
+		__field(u32, sequence)
+	),
+
+	TP_fast_assign(
+		struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
+		struct v4l2_fh *owner = q->owner;
+
+		__entry->minor = owner ? owner->vdev->minor : -1;
+		__entry->flags = vbuf->flags;
+		__entry->field = vbuf->field;
+		__entry->timestamp = vb->timestamp;
+		__entry->timecode_type = vbuf->timecode.type;
+		__entry->timecode_flags = vbuf->timecode.flags;
+		__entry->timecode_frames = vbuf->timecode.frames;
+		__entry->timecode_seconds = vbuf->timecode.seconds;
+		__entry->timecode_minutes = vbuf->timecode.minutes;
+		__entry->timecode_hours = vbuf->timecode.hours;
+		__entry->timecode_userbits0 = vbuf->timecode.userbits[0];
+		__entry->timecode_userbits1 = vbuf->timecode.userbits[1];
+		__entry->timecode_userbits2 = vbuf->timecode.userbits[2];
+		__entry->timecode_userbits3 = vbuf->timecode.userbits[3];
+		__entry->sequence = vbuf->sequence;
+	),
+
+	TP_printk("minor=%d flags = %s, field = %s, "
+		  "timestamp = %llu, timecode = { type = %s, flags = %s, "
+		  "frames = %u, seconds = %u, minutes = %u, hours = %u, "
+		  "userbits = { %u %u %u %u } }, sequence = %u", __entry->minor,
+		  show_flags(__entry->flags),
+		  show_field(__entry->field),
+		  __entry->timestamp,
+		  show_timecode_type(__entry->timecode_type),
+		  show_timecode_flags(__entry->timecode_flags),
+		  __entry->timecode_frames,
+		  __entry->timecode_seconds,
+		  __entry->timecode_minutes,
+		  __entry->timecode_hours,
+		  __entry->timecode_userbits0,
+		  __entry->timecode_userbits1,
+		  __entry->timecode_userbits2,
+		  __entry->timecode_userbits3,
+		  __entry->sequence
+	)
+)
+
+DEFINE_EVENT(vb2_v4l2_event_class, vb2_v4l2_buf_done,
+	TP_PROTO(struct vb2_queue *q, struct vb2_buffer *vb),
+	TP_ARGS(q, vb)
+);
+
+DEFINE_EVENT(vb2_v4l2_event_class, vb2_v4l2_buf_queue,
+	TP_PROTO(struct vb2_queue *q, struct vb2_buffer *vb),
+	TP_ARGS(q, vb)
+);
+
+DEFINE_EVENT(vb2_v4l2_event_class, vb2_v4l2_dqbuf,
+	TP_PROTO(struct vb2_queue *q, struct vb2_buffer *vb),
+	TP_ARGS(q, vb)
+);
+
+DEFINE_EVENT(vb2_v4l2_event_class, vb2_v4l2_qbuf,
+	TP_PROTO(struct vb2_queue *q, struct vb2_buffer *vb),
+	TP_ARGS(q, vb)
+);
+
+#endif /* if !defined(_TRACE_V4L2_H) || defined(TRACE_HEADER_MULTI_READ) */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>