Commit 48b77ad6 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

block: cleanup tracing 



A couple tweaks to the tracing code:

 - trace the request size for all requests
 - trace request sector and nr_sectors only for fs requests, enforced by
   helpers
 - drop SCSI CDB tracing - we have SCSI tracing for this and are going
   to me the CDB out of the generic struct request soon.

With this the tracing code stops to know about BLOCK_PC requests entirely,
it's just FS vs passthrough requests now, where the latter includes any
driver-private requests.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarJens Axboe <axboe@fb.com>
parent 6d247d7f

include/linux/blktrace_api.h

+7 −7
Original line number Diff line number Diff line
@@ -110,16 +110,16 @@ struct compat_blk_user_trace_setup { 


#endif



#if defined(CONFIG_EVENT_TRACING) && defined(CONFIG_BLOCK)

extern void blk_fill_rwbs(char *rwbs, unsigned int op, int bytes);



static inline int blk_cmd_buf_len(struct request *rq)

static inline sector_t blk_rq_trace_sector(struct request *rq)

{

	return (rq->cmd_type == REQ_TYPE_BLOCK_PC) ? rq->cmd_len * 3 : 1;

	return (rq->cmd_type != REQ_TYPE_FS) ? 0 : blk_rq_pos(rq);

}



extern void blk_dump_cmd(char *buf, struct request *rq);

extern void blk_fill_rwbs(char *rwbs, unsigned int op, int bytes);



#endif /* CONFIG_EVENT_TRACING && CONFIG_BLOCK */

static inline unsigned int blk_rq_trace_nr_sectors(struct request *rq)

{

	return (rq->cmd_type != REQ_TYPE_FS) ? 0 : blk_rq_sectors(rq);

}



#endif

include/trace/events/block.h

+11 −16
Original line number Diff line number Diff line
@@ -73,19 +73,17 @@ DECLARE_EVENT_CLASS(block_rq_with_error, 
		__field(  unsigned int,	nr_sector		)

		__field(  int,		errors			)

		__array(  char,		rwbs,	RWBS_LEN	)

		__dynamic_array( char,	cmd,	blk_cmd_buf_len(rq)	)

		__dynamic_array( char,	cmd,	1		)

	),



	TP_fast_assign(

		__entry->dev	   = rq->rq_disk ? disk_devt(rq->rq_disk) : 0;

		__entry->sector    = (rq->cmd_type == REQ_TYPE_BLOCK_PC) ?

					0 : blk_rq_pos(rq);

		__entry->nr_sector = (rq->cmd_type == REQ_TYPE_BLOCK_PC) ?

					0 : blk_rq_sectors(rq);

		__entry->sector    = blk_rq_trace_sector(rq);

		__entry->nr_sector = blk_rq_trace_nr_sectors(rq);

		__entry->errors    = rq->errors;



		blk_fill_rwbs(__entry->rwbs, rq->cmd_flags, blk_rq_bytes(rq));

		blk_dump_cmd(__get_str(cmd), rq);

		__get_str(cmd)[0] = '\0';

	),



	TP_printk("%d,%d %s (%s) %llu + %u [%d]",
@@ -153,7 +151,7 @@ TRACE_EVENT(block_rq_complete, 
		__field(  unsigned int,	nr_sector		)

		__field(  int,		errors			)

		__array(  char,		rwbs,	RWBS_LEN	)

		__dynamic_array( char,	cmd,	blk_cmd_buf_len(rq)	)

		__dynamic_array( char,	cmd,	1		)

	),



	TP_fast_assign(
@@ -163,7 +161,7 @@ TRACE_EVENT(block_rq_complete, 
		__entry->errors    = rq->errors;



		blk_fill_rwbs(__entry->rwbs, rq->cmd_flags, nr_bytes);

		blk_dump_cmd(__get_str(cmd), rq);

		__get_str(cmd)[0] = '\0';

	),



	TP_printk("%d,%d %s (%s) %llu + %u [%d]",
@@ -186,20 +184,17 @@ DECLARE_EVENT_CLASS(block_rq, 
		__field(  unsigned int,	bytes			)

		__array(  char,		rwbs,	RWBS_LEN	)

		__array(  char,         comm,   TASK_COMM_LEN   )

		__dynamic_array( char,	cmd,	blk_cmd_buf_len(rq)	)

		__dynamic_array( char,	cmd,	1		)

	),



	TP_fast_assign(

		__entry->dev	   = rq->rq_disk ? disk_devt(rq->rq_disk) : 0;

		__entry->sector    = (rq->cmd_type == REQ_TYPE_BLOCK_PC) ?

					0 : blk_rq_pos(rq);

		__entry->nr_sector = (rq->cmd_type == REQ_TYPE_BLOCK_PC) ?

					0 : blk_rq_sectors(rq);

		__entry->bytes     = (rq->cmd_type == REQ_TYPE_BLOCK_PC) ?

					blk_rq_bytes(rq) : 0;

		__entry->sector    = blk_rq_trace_sector(rq);

		__entry->nr_sector = blk_rq_trace_nr_sectors(rq);

		__entry->bytes     = blk_rq_bytes(rq);



		blk_fill_rwbs(__entry->rwbs, rq->cmd_flags, blk_rq_bytes(rq));

		blk_dump_cmd(__get_str(cmd), rq);

		__get_str(cmd)[0] = '\0';

		memcpy(__entry->comm, current->comm, TASK_COMM_LEN);

	),

kernel/trace/blktrace.c

+6 −37
Original line number Diff line number Diff line
@@ -712,16 +712,14 @@ static void blk_add_trace_rq(struct request_queue *q, struct request *rq, 
	if (likely(!bt))

		return;



	if (rq->cmd_type == REQ_TYPE_BLOCK_PC) {

	if (rq->cmd_type != REQ_TYPE_FS)

		what |= BLK_TC_ACT(BLK_TC_PC);

		__blk_add_trace(bt, 0, nr_bytes, req_op(rq), rq->cmd_flags,

				what, rq->errors, rq->cmd_len, rq->cmd);

	} else  {

	else

		what |= BLK_TC_ACT(BLK_TC_FS);

		__blk_add_trace(bt, blk_rq_pos(rq), nr_bytes, req_op(rq),



	__blk_add_trace(bt, blk_rq_trace_sector(rq), nr_bytes, req_op(rq),

			rq->cmd_flags, what, rq->errors, 0, NULL);

}

}



static void blk_add_trace_rq_abort(void *ignore,

				   struct request_queue *q, struct request *rq)
@@ -972,11 +970,7 @@ void blk_add_driver_data(struct request_queue *q, 
	if (likely(!bt))

		return;



	if (rq->cmd_type == REQ_TYPE_BLOCK_PC)

		__blk_add_trace(bt, 0, blk_rq_bytes(rq), 0, 0,

				BLK_TA_DRV_DATA, rq->errors, len, data);

	else

		__blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), 0, 0,

	__blk_add_trace(bt, blk_rq_trace_sector(rq), blk_rq_bytes(rq), 0, 0,

				BLK_TA_DRV_DATA, rq->errors, len, data);

}

EXPORT_SYMBOL_GPL(blk_add_driver_data);
@@ -1752,31 +1746,6 @@ void blk_trace_remove_sysfs(struct device *dev) 


#ifdef CONFIG_EVENT_TRACING



void blk_dump_cmd(char *buf, struct request *rq)

{

	int i, end;

	int len = rq->cmd_len;

	unsigned char *cmd = rq->cmd;



	if (rq->cmd_type != REQ_TYPE_BLOCK_PC) {

		buf[0] = '\0';

		return;

	}



	for (end = len - 1; end >= 0; end--)

		if (cmd[end])

			break;

	end++;



	for (i = 0; i < len; i++) {

		buf += sprintf(buf, "%s%02x", i == 0 ? "" : " ", cmd[i]);

		if (i == end && end != len - 1) {

			sprintf(buf, " ..");

			break;

		}

	}

}



void blk_fill_rwbs(char *rwbs, unsigned int op, int bytes)

{

	int i = 0;

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