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: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/include/linux/blktrace_api.h b/include/linux/blktrace_api.h
index e417f08..a143a67 100644
--- a/include/linux/blktrace_api.h
+++ b/include/linux/blktrace_api.h
@@ -110,16 +110,16 @@ struct compat_blk_user_trace_setup {
#endif
-#if defined(CONFIG_EVENT_TRACING) && defined(CONFIG_BLOCK)
-
-static inline int blk_cmd_buf_len(struct request *rq)
-{
- return (rq->cmd_type == REQ_TYPE_BLOCK_PC) ? rq->cmd_len * 3 : 1;
-}
-
-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 sector_t blk_rq_trace_sector(struct request *rq)
+{
+ return (rq->cmd_type != REQ_TYPE_FS) ? 0 : blk_rq_pos(rq);
+}
+
+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
diff --git a/include/trace/events/block.h b/include/trace/events/block.h
index 3e02e3a..a88ed13 100644
--- a/include/trace/events/block.h
+++ b/include/trace/events/block.h
@@ -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);
),
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index 95cecbf..512b347 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -712,15 +712,13 @@ 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),
- rq->cmd_flags, what, rq->errors, 0, NULL);
- }
+
+ __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,
@@ -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;