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, 193 insertions, 0 deletions

diff --git a/include/trace/events/mmc.h b/include/trace/events/mmc.h
new file mode 100644
index 000000000..f1c2e94f7
--- /dev/null
+++ b/include/trace/events/mmc.h
@@ -0,0 +1,193 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM mmc
+
+#if !defined(_TRACE_MMC_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_MMC_H
+
+#include <linux/blkdev.h>
+#include <linux/mmc/core.h>
+#include <linux/mmc/host.h>
+#include <linux/tracepoint.h>
+
+TRACE_EVENT(mmc_request_start,
+
+	TP_PROTO(struct mmc_host *host, struct mmc_request *mrq),
+
+	TP_ARGS(host, mrq),
+
+	TP_STRUCT__entry(
+		__field(u32,			cmd_opcode)
+		__field(u32,			cmd_arg)
+		__field(unsigned int,		cmd_flags)
+		__field(unsigned int,		cmd_retries)
+		__field(u32,			stop_opcode)
+		__field(u32,			stop_arg)
+		__field(unsigned int,		stop_flags)
+		__field(unsigned int,		stop_retries)
+		__field(u32,			sbc_opcode)
+		__field(u32,			sbc_arg)
+		__field(unsigned int,		sbc_flags)
+		__field(unsigned int,		sbc_retries)
+		__field(unsigned int,		blocks)
+		__field(unsigned int,		blk_addr)
+		__field(unsigned int,		blksz)
+		__field(unsigned int,		data_flags)
+		__field(int,			tag)
+		__field(unsigned int,		can_retune)
+		__field(unsigned int,		doing_retune)
+		__field(unsigned int,		retune_now)
+		__field(int,			need_retune)
+		__field(int,			hold_retune)
+		__field(unsigned int,		retune_period)
+		__field(struct mmc_request *,	mrq)
+		__string(name,			mmc_hostname(host))
+	),
+
+	TP_fast_assign(
+		__entry->cmd_opcode = mrq->cmd ? mrq->cmd->opcode : 0;
+		__entry->cmd_arg = mrq->cmd ? mrq->cmd->arg : 0;
+		__entry->cmd_flags = mrq->cmd ? mrq->cmd->flags : 0;
+		__entry->cmd_retries = mrq->cmd ? mrq->cmd->retries : 0;
+		__entry->stop_opcode = mrq->stop ? mrq->stop->opcode : 0;
+		__entry->stop_arg = mrq->stop ? mrq->stop->arg : 0;
+		__entry->stop_flags = mrq->stop ? mrq->stop->flags : 0;
+		__entry->stop_retries = mrq->stop ? mrq->stop->retries : 0;
+		__entry->sbc_opcode = mrq->sbc ? mrq->sbc->opcode : 0;
+		__entry->sbc_arg = mrq->sbc ? mrq->sbc->arg : 0;
+		__entry->sbc_flags = mrq->sbc ? mrq->sbc->flags : 0;
+		__entry->sbc_retries = mrq->sbc ? mrq->sbc->retries : 0;
+		__entry->blksz = mrq->data ? mrq->data->blksz : 0;
+		__entry->blocks = mrq->data ? mrq->data->blocks : 0;
+		__entry->blk_addr = mrq->data ? mrq->data->blk_addr : 0;
+		__entry->data_flags = mrq->data ? mrq->data->flags : 0;
+		__entry->tag = mrq->tag;
+		__entry->can_retune = host->can_retune;
+		__entry->doing_retune = host->doing_retune;
+		__entry->retune_now = host->retune_now;
+		__entry->need_retune = host->need_retune;
+		__entry->hold_retune = host->hold_retune;
+		__entry->retune_period = host->retune_period;
+		__assign_str(name);
+		__entry->mrq = mrq;
+	),
+
+	TP_printk("%s: start struct mmc_request[%p]: "
+		  "cmd_opcode=%u cmd_arg=0x%x cmd_flags=0x%x cmd_retries=%u "
+		  "stop_opcode=%u stop_arg=0x%x stop_flags=0x%x stop_retries=%u "
+		  "sbc_opcode=%u sbc_arg=0x%x sbc_flags=0x%x sbc_retires=%u "
+		  "blocks=%u block_size=%u blk_addr=%u data_flags=0x%x "
+		  "tag=%d can_retune=%u doing_retune=%u retune_now=%u "
+		  "need_retune=%d hold_retune=%d retune_period=%u",
+		  __get_str(name), __entry->mrq,
+		  __entry->cmd_opcode, __entry->cmd_arg,
+		  __entry->cmd_flags, __entry->cmd_retries,
+		  __entry->stop_opcode, __entry->stop_arg,
+		  __entry->stop_flags, __entry->stop_retries,
+		  __entry->sbc_opcode, __entry->sbc_arg,
+		  __entry->sbc_flags, __entry->sbc_retries,
+		  __entry->blocks, __entry->blksz,
+		  __entry->blk_addr, __entry->data_flags, __entry->tag,
+		  __entry->can_retune, __entry->doing_retune,
+		  __entry->retune_now, __entry->need_retune,
+		  __entry->hold_retune, __entry->retune_period)
+);
+
+TRACE_EVENT(mmc_request_done,
+
+	TP_PROTO(struct mmc_host *host, struct mmc_request *mrq),
+
+	TP_ARGS(host, mrq),
+
+	TP_STRUCT__entry(
+		__field(u32,			cmd_opcode)
+		__field(int,			cmd_err)
+		__array(u32,			cmd_resp,	4)
+		__field(unsigned int,		cmd_retries)
+		__field(u32,			stop_opcode)
+		__field(int,			stop_err)
+		__array(u32,			stop_resp,	4)
+		__field(unsigned int,		stop_retries)
+		__field(u32,			sbc_opcode)
+		__field(int,			sbc_err)
+		__array(u32,			sbc_resp,	4)
+		__field(unsigned int,		sbc_retries)
+		__field(unsigned int,		bytes_xfered)
+		__field(int,			data_err)
+		__field(int,			tag)
+		__field(unsigned int,		can_retune)
+		__field(unsigned int,		doing_retune)
+		__field(unsigned int,		retune_now)
+		__field(int,			need_retune)
+		__field(int,			hold_retune)
+		__field(unsigned int,		retune_period)
+		__field(struct mmc_request *,	mrq)
+		__string(name,			mmc_hostname(host))
+	),
+
+	TP_fast_assign(
+		__entry->cmd_opcode = mrq->cmd ? mrq->cmd->opcode : 0;
+		__entry->cmd_err = mrq->cmd ? mrq->cmd->error : 0;
+		__entry->cmd_resp[0] = mrq->cmd ? mrq->cmd->resp[0] : 0;
+		__entry->cmd_resp[1] = mrq->cmd ? mrq->cmd->resp[1] : 0;
+		__entry->cmd_resp[2] = mrq->cmd ? mrq->cmd->resp[2] : 0;
+		__entry->cmd_resp[3] = mrq->cmd ? mrq->cmd->resp[3] : 0;
+		__entry->cmd_retries = mrq->cmd ? mrq->cmd->retries : 0;
+		__entry->stop_opcode = mrq->stop ? mrq->stop->opcode : 0;
+		__entry->stop_err = mrq->stop ? mrq->stop->error : 0;
+		__entry->stop_resp[0] = mrq->stop ? mrq->stop->resp[0] : 0;
+		__entry->stop_resp[1] = mrq->stop ? mrq->stop->resp[1] : 0;
+		__entry->stop_resp[2] = mrq->stop ? mrq->stop->resp[2] : 0;
+		__entry->stop_resp[3] = mrq->stop ? mrq->stop->resp[3] : 0;
+		__entry->stop_retries = mrq->stop ? mrq->stop->retries : 0;
+		__entry->sbc_opcode = mrq->sbc ? mrq->sbc->opcode : 0;
+		__entry->sbc_err = mrq->sbc ? mrq->sbc->error : 0;
+		__entry->sbc_resp[0] = mrq->sbc ? mrq->sbc->resp[0] : 0;
+		__entry->sbc_resp[1] = mrq->sbc ? mrq->sbc->resp[1] : 0;
+		__entry->sbc_resp[2] = mrq->sbc ? mrq->sbc->resp[2] : 0;
+		__entry->sbc_resp[3] = mrq->sbc ? mrq->sbc->resp[3] : 0;
+		__entry->sbc_retries = mrq->sbc ? mrq->sbc->retries : 0;
+		__entry->bytes_xfered = mrq->data ? mrq->data->bytes_xfered : 0;
+		__entry->data_err = mrq->data ? mrq->data->error : 0;
+		__entry->tag = mrq->tag;
+		__entry->can_retune = host->can_retune;
+		__entry->doing_retune = host->doing_retune;
+		__entry->retune_now = host->retune_now;
+		__entry->need_retune = host->need_retune;
+		__entry->hold_retune = host->hold_retune;
+		__entry->retune_period = host->retune_period;
+		__assign_str(name);
+		__entry->mrq = mrq;
+	),
+
+	TP_printk("%s: end struct mmc_request[%p]: "
+		  "cmd_opcode=%u cmd_err=%d cmd_resp=0x%x 0x%x 0x%x 0x%x "
+		  "cmd_retries=%u stop_opcode=%u stop_err=%d "
+		  "stop_resp=0x%x 0x%x 0x%x 0x%x stop_retries=%u "
+		  "sbc_opcode=%u sbc_err=%d sbc_resp=0x%x 0x%x 0x%x 0x%x "
+		  "sbc_retries=%u bytes_xfered=%u data_err=%d tag=%d "
+		  "can_retune=%u doing_retune=%u retune_now=%u need_retune=%d "
+		  "hold_retune=%d retune_period=%u",
+		  __get_str(name), __entry->mrq,
+		  __entry->cmd_opcode, __entry->cmd_err,
+		  __entry->cmd_resp[0], __entry->cmd_resp[1],
+		  __entry->cmd_resp[2], __entry->cmd_resp[3],
+		  __entry->cmd_retries,
+		  __entry->stop_opcode, __entry->stop_err,
+		  __entry->stop_resp[0], __entry->stop_resp[1],
+		  __entry->stop_resp[2], __entry->stop_resp[3],
+		  __entry->stop_retries,
+		  __entry->sbc_opcode, __entry->sbc_err,
+		  __entry->sbc_resp[0], __entry->sbc_resp[1],
+		  __entry->sbc_resp[2], __entry->sbc_resp[3],
+		  __entry->sbc_retries,
+		  __entry->bytes_xfered, __entry->data_err, __entry->tag,
+		  __entry->can_retune, __entry->doing_retune,
+		  __entry->retune_now, __entry->need_retune,
+		  __entry->hold_retune, __entry->retune_period)
+);
+
+#endif /* _TRACE_MMC_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>