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, 239 insertions, 0 deletions

diff --git a/include/trace/events/spi.h b/include/trace/events/spi.h
new file mode 100644
index 000000000..e63d4a24d
--- /dev/null
+++ b/include/trace/events/spi.h
@@ -0,0 +1,239 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM spi
+
+#if !defined(_TRACE_SPI_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_SPI_H
+
+#include <linux/ktime.h>
+#include <linux/tracepoint.h>
+
+DECLARE_EVENT_CLASS(spi_controller,
+
+	TP_PROTO(struct spi_controller *controller),
+
+	TP_ARGS(controller),
+
+	TP_STRUCT__entry(
+		__field(        int,           bus_num             )
+	),
+
+	TP_fast_assign(
+		__entry->bus_num = controller->bus_num;
+	),
+
+	TP_printk("spi%d", (int)__entry->bus_num)
+
+);
+
+DEFINE_EVENT(spi_controller, spi_controller_idle,
+
+	TP_PROTO(struct spi_controller *controller),
+
+	TP_ARGS(controller)
+
+);
+
+DEFINE_EVENT(spi_controller, spi_controller_busy,
+
+	TP_PROTO(struct spi_controller *controller),
+
+	TP_ARGS(controller)
+
+);
+
+TRACE_EVENT(spi_setup,
+	TP_PROTO(struct spi_device *spi, int status),
+	TP_ARGS(spi, status),
+
+	TP_STRUCT__entry(
+		__field(int, bus_num)
+		__field(int, chip_select)
+		__field(unsigned long, mode)
+		__field(unsigned int, bits_per_word)
+		__field(unsigned int, max_speed_hz)
+		__field(int, status)
+	),
+
+	TP_fast_assign(
+		__entry->bus_num = spi->controller->bus_num;
+		__entry->chip_select =  spi_get_chipselect(spi, 0);
+		__entry->mode = spi->mode;
+		__entry->bits_per_word = spi->bits_per_word;
+		__entry->max_speed_hz = spi->max_speed_hz;
+		__entry->status = status;
+	),
+
+	TP_printk("spi%d.%d setup mode %lu, %s%s%s%s%u bits/w, %u Hz max --> %d",
+		  __entry->bus_num, __entry->chip_select,
+		  (__entry->mode & SPI_MODE_X_MASK),
+		  (__entry->mode & SPI_CS_HIGH) ? "cs_high, " : "",
+		  (__entry->mode & SPI_LSB_FIRST) ? "lsb, " : "",
+		  (__entry->mode & SPI_3WIRE) ? "3wire, " : "",
+		  (__entry->mode & SPI_LOOP) ? "loopback, " : "",
+		  __entry->bits_per_word, __entry->max_speed_hz,
+		  __entry->status)
+);
+
+TRACE_EVENT(spi_set_cs,
+	TP_PROTO(struct spi_device *spi, bool enable),
+	TP_ARGS(spi, enable),
+
+	TP_STRUCT__entry(
+		__field(int, bus_num)
+		__field(int, chip_select)
+		__field(unsigned long, mode)
+		__field(bool, enable)
+	),
+
+	TP_fast_assign(
+		__entry->bus_num = spi->controller->bus_num;
+		__entry->chip_select = spi_get_chipselect(spi, 0);
+		__entry->mode = spi->mode;
+		__entry->enable = enable;
+	),
+
+	TP_printk("spi%d.%d %s%s",
+		  __entry->bus_num, __entry->chip_select,
+		  __entry->enable ? "activate" : "deactivate",
+		  (__entry->mode & SPI_CS_HIGH) ? ", cs_high" : "")
+);
+
+DECLARE_EVENT_CLASS(spi_message,
+
+	TP_PROTO(struct spi_message *msg),
+
+	TP_ARGS(msg),
+
+	TP_STRUCT__entry(
+		__field(        int,            bus_num         )
+		__field(        int,            chip_select     )
+		__field(        struct spi_message *,   msg     )
+	),
+
+	TP_fast_assign(
+		__entry->bus_num = msg->spi->controller->bus_num;
+		__entry->chip_select = spi_get_chipselect(msg->spi, 0);
+		__entry->msg = msg;
+	),
+
+        TP_printk("spi%d.%d %p", (int)__entry->bus_num,
+		  (int)__entry->chip_select,
+		  (struct spi_message *)__entry->msg)
+);
+
+DEFINE_EVENT(spi_message, spi_message_submit,
+
+	TP_PROTO(struct spi_message *msg),
+
+	TP_ARGS(msg)
+
+);
+
+DEFINE_EVENT(spi_message, spi_message_start,
+
+	TP_PROTO(struct spi_message *msg),
+
+	TP_ARGS(msg)
+
+);
+
+TRACE_EVENT(spi_message_done,
+
+	TP_PROTO(struct spi_message *msg),
+
+	TP_ARGS(msg),
+
+	TP_STRUCT__entry(
+		__field(        int,            bus_num         )
+		__field(        int,            chip_select     )
+		__field(        struct spi_message *,   msg     )
+		__field(        unsigned,       frame           )
+		__field(        unsigned,       actual          )
+	),
+
+	TP_fast_assign(
+		__entry->bus_num = msg->spi->controller->bus_num;
+		__entry->chip_select = spi_get_chipselect(msg->spi, 0);
+		__entry->msg = msg;
+		__entry->frame = msg->frame_length;
+		__entry->actual = msg->actual_length;
+	),
+
+        TP_printk("spi%d.%d %p len=%u/%u", (int)__entry->bus_num,
+		  (int)__entry->chip_select,
+		  (struct spi_message *)__entry->msg,
+                  (unsigned)__entry->actual, (unsigned)__entry->frame)
+);
+
+/*
+ * Consider a buffer valid if non-NULL and if it doesn't match the dummy buffer
+ * that only exist to work with controllers that have SPI_CONTROLLER_MUST_TX or
+ * SPI_CONTROLLER_MUST_RX.
+ */
+#define spi_valid_txbuf(msg, xfer) \
+	(xfer->tx_buf && xfer->tx_buf != msg->spi->controller->dummy_tx)
+#define spi_valid_rxbuf(msg, xfer) \
+	(xfer->rx_buf && xfer->rx_buf != msg->spi->controller->dummy_rx)
+
+DECLARE_EVENT_CLASS(spi_transfer,
+
+	TP_PROTO(struct spi_message *msg, struct spi_transfer *xfer),
+
+	TP_ARGS(msg, xfer),
+
+	TP_STRUCT__entry(
+		__field(        int,            bus_num         )
+		__field(        int,            chip_select     )
+		__field(        struct spi_transfer *,   xfer   )
+		__field(        int,            len             )
+		__dynamic_array(u8, rx_buf,
+				spi_valid_rxbuf(msg, xfer) ?
+					(xfer->len < 64 ? xfer->len : 64) : 0)
+		__dynamic_array(u8, tx_buf,
+				spi_valid_txbuf(msg, xfer) ?
+					(xfer->len < 64 ? xfer->len : 64) : 0)
+	),
+
+	TP_fast_assign(
+		__entry->bus_num = msg->spi->controller->bus_num;
+		__entry->chip_select = spi_get_chipselect(msg->spi, 0);
+		__entry->xfer = xfer;
+		__entry->len = xfer->len;
+
+		if (spi_valid_txbuf(msg, xfer))
+			memcpy(__get_dynamic_array(tx_buf),
+			       xfer->tx_buf, __get_dynamic_array_len(tx_buf));
+
+		if (spi_valid_rxbuf(msg, xfer))
+			memcpy(__get_dynamic_array(rx_buf),
+			       xfer->rx_buf, __get_dynamic_array_len(rx_buf));
+	),
+
+	TP_printk("spi%d.%d %p len=%d tx=[%*phD] rx=[%*phD]",
+		  __entry->bus_num, __entry->chip_select,
+		  __entry->xfer, __entry->len,
+		  __get_dynamic_array_len(tx_buf), __get_dynamic_array(tx_buf),
+		  __get_dynamic_array_len(rx_buf), __get_dynamic_array(rx_buf))
+);
+
+DEFINE_EVENT(spi_transfer, spi_transfer_start,
+
+	TP_PROTO(struct spi_message *msg, struct spi_transfer *xfer),
+
+	TP_ARGS(msg, xfer)
+
+);
+
+DEFINE_EVENT(spi_transfer, spi_transfer_stop,
+
+	TP_PROTO(struct spi_message *msg, struct spi_transfer *xfer),
+
+	TP_ARGS(msg, xfer)
+
+);
+
+#endif /* _TRACE_POWER_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>