]> git.baikalelectronics.ru Git - kernel.git/commit
scsi: trace: Print driver_tag and scheduler_tag in SCSI trace
authorChangyuan Lyu <changyuanl@google.com>
Tue, 21 Jun 2022 18:11:25 +0000 (18:11 +0000)
committerMartin K. Petersen <martin.petersen@oracle.com>
Wed, 22 Jun 2022 01:43:23 +0000 (21:43 -0400)
commit34fa4bc7e85e076c50f7c259688d14133a9a51e1
tree3311bccf12d23b364826e08369217b0a74fb29ec
parent725105ae6c2adfd7b981a26f647e51dce9b077ee
scsi: trace: Print driver_tag and scheduler_tag in SCSI trace

Trace events like scsi_dispatch_cmd_start and scsi_dispatch_cmd_done are
useful for tracking a command throughout its lifetime. But for some ATA
passthrough commands, the information printed in current logs is not enough
to identify and match them. For example, if two threads send SMART cmd to
the same disk at the same time, their trace logs may look the same, which
makes it hard to match scsi_dispatch_cmd_done and scsi_dispatch_cmd_start.

Printing tags can help us solve the problem.  Further, if a command failed
for some reason and then is retried, its driver_tag will change. So
scheduler_tag is also included such that we can track the retries of a
command.

Link: https://lore.kernel.org/r/20220621181125.3211399-1-changyuanl@google.com
Reviewed-by: Vishakha Channapattan <vishakhavc@google.com>
Reviewed-by: Jolly Shah <jollys@google.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Changyuan Lyu <changyuanl@google.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
include/trace/events/scsi.h