[PATCH v4] mmc: Provide tracepoints for request processing

From: Baolin Wang
Date: Wed Mar 30 2016 - 23:17:39 EST


This patch provides some tracepoints for the lifecycle of a mmc request from
starting to completion to help with performance analysis of MMC subsystem.

Changes since v3:
- Add "retries" and "re-tune state" in the trace print.
- Move trace_mmc_request_start() to __mmc_start_request() function to avoid
missing valuable information about which command/request is being sent.

Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx>
---
drivers/mmc/core/core.c | 7 ++
include/trace/events/mmc.h | 182 ++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 189 insertions(+)
create mode 100644 include/trace/events/mmc.h

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index f95d41f..98ff0f9 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -36,6 +36,9 @@
#include <linux/mmc/sd.h>
#include <linux/mmc/slot-gpio.h>

+#define CREATE_TRACE_POINTS
+#include <trace/events/mmc.h>
+
#include "core.h"
#include "bus.h"
#include "host.h"
@@ -140,6 +143,8 @@ void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq)
cmd->retries = 0;
}

+ trace_mmc_request_done(host, mrq);
+
if (err && cmd->retries && !mmc_card_removed(host->card)) {
/*
* Request starter must handle retries - see
@@ -215,6 +220,8 @@ static void __mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
}
}

+ trace_mmc_request_start(host, mrq);
+
host->ops->request(host, mrq);
}

diff --git a/include/trace/events/mmc.h b/include/trace/events/mmc.h
new file mode 100644
index 0000000..a72f9b9
--- /dev/null
+++ b/include/trace/events/mmc.h
@@ -0,0 +1,182 @@
+#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, blksz)
+ __field(unsigned int, data_flags)
+ __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->opcode;
+ __entry->cmd_arg = mrq->cmd->arg;
+ __entry->cmd_flags = mrq->cmd->flags;
+ __entry->cmd_retries = mrq->cmd->retries;
+ __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->data_flags = mrq->data ? mrq->data->flags : 0;
+ __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, mmc_hostname(host));
+ __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 data_flags=0x%x "
+ "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->data_flags,
+ __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(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->opcode;
+ __entry->cmd_err = mrq->cmd->error;
+ memcpy(__entry->cmd_resp, mrq->cmd->resp, 4);
+ __entry->cmd_retries = mrq->cmd->retries;
+ __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->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, mmc_hostname(host));
+ __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 "
+ "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->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>
--
1.7.9.5