On 9/29/20 7:59 AM, Roman Bolshakov wrote:
> trace-cmd report doesn't show events from target subsystem because
> scsi_command_size() leaks through event format string:
>
> [target:target_sequencer_start] function scsi_command_size not defined
> [target:target_cmd_complete] function scsi_command_size not defined
>
> Addition of scsi_command_size() to plugin_scsi.c in trace-cmd doesn't
> help because an expression is used inside TP_printk(). trace-cmd event
> parser doesn't understand minus sign inside [ ]:
>
> Error: expected ']' but read '-'
>
> Rather than duplicating kernel code in plugin_scsi.c, it's better to
> provide a dedicated field for CONTROL byte.
>
> Signed-off-by: Roman Bolshakov <r.bolshakov@xxxxxxxxx>
> ---
> include/scsi/scsi_common.h | 7 +++++++
> include/trace/events/target.h | 12 ++++++------
> 2 files changed, 13 insertions(+), 6 deletions(-)
>
> diff --git a/include/scsi/scsi_common.h b/include/scsi/scsi_common.h
> index 731ac09ed231..5b567b43e1b1 100644
> --- a/include/scsi/scsi_common.h
> +++ b/include/scsi/scsi_common.h
> @@ -25,6 +25,13 @@ scsi_command_size(const unsigned char *cmnd)
> scsi_varlen_cdb_length(cmnd) : COMMAND_SIZE(cmnd[0]);
> }
>
> +static inline unsigned char
> +scsi_command_control(const unsigned char *cmnd)
> +{
> + return (cmnd[0] == VARIABLE_LENGTH_CMD) ?
> + cmnd[1] : cmnd[COMMAND_SIZE(cmnd[0]) - 1];
> +}
> +
> /* Returns a human-readable name for the device */
> extern const char *scsi_device_type(unsigned type);
>
> diff --git a/include/trace/events/target.h b/include/trace/events/target.h
> index 77408edd29d2..67fad2677ed5 100644
> --- a/include/trace/events/target.h
> +++ b/include/trace/events/target.h
> @@ -141,6 +141,7 @@ TRACE_EVENT(target_sequencer_start,
> __field( unsigned int, opcode )
> __field( unsigned int, data_length )
> __field( unsigned int, task_attribute )
> + __field( unsigned char, control )
> __array( unsigned char, cdb, TCM_MAX_COMMAND_SIZE )
> __string( initiator, cmd->se_sess->se_node_acl->initiatorname )
> ),
> @@ -151,6 +152,7 @@ TRACE_EVENT(target_sequencer_start,
> __entry->opcode = cmd->t_task_cdb[0];
> __entry->data_length = cmd->data_length;
> __entry->task_attribute = cmd->sam_task_attr;
> + __entry->control = scsi_command_control(cmd->t_task_cdb);
> memcpy(__entry->cdb, cmd->t_task_cdb, TCM_MAX_COMMAND_SIZE);
> __assign_str(initiator, cmd->se_sess->se_node_acl->initiatorname);
> ),
> @@ -160,9 +162,7 @@ TRACE_EVENT(target_sequencer_start,
> __entry->tag, show_opcode_name(__entry->opcode),
> __entry->data_length, __print_hex(__entry->cdb, 16),
> show_task_attribute_name(__entry->task_attribute),
> - scsi_command_size(__entry->cdb) <= 16 ?
> - __entry->cdb[scsi_command_size(__entry->cdb) - 1] :
> - __entry->cdb[1]
> + __entry->control
> )
> );
>
> @@ -178,6 +178,7 @@ TRACE_EVENT(target_cmd_complete,
> __field( unsigned int, opcode )
> __field( unsigned int, data_length )
> __field( unsigned int, task_attribute )
> + __field( unsigned char, control )
> __field( unsigned char, scsi_status )
> __field( unsigned char, sense_length )
> __array( unsigned char, cdb, TCM_MAX_COMMAND_SIZE )
> @@ -191,6 +192,7 @@ TRACE_EVENT(target_cmd_complete,
> __entry->opcode = cmd->t_task_cdb[0];
> __entry->data_length = cmd->data_length;
> __entry->task_attribute = cmd->sam_task_attr;
> + __entry->control = scsi_command_control(cmd->t_task_cdb);
> __entry->scsi_status = cmd->scsi_status;
> __entry->sense_length = cmd->scsi_status == SAM_STAT_CHECK_CONDITION ?
> min(18, ((u8 *) cmd->sense_buffer)[SPC_ADD_SENSE_LEN_OFFSET] + 8) : 0;
> @@ -208,9 +210,7 @@ TRACE_EVENT(target_cmd_complete,
> show_opcode_name(__entry->opcode),
> __entry->data_length, __print_hex(__entry->cdb, 16),
> show_task_attribute_name(__entry->task_attribute),
> - scsi_command_size(__entry->cdb) <= 16 ?
> - __entry->cdb[scsi_command_size(__entry->cdb) - 1] :
> - __entry->cdb[1]
> + __entry->control
> )
> );
>
I'm not an expert on the tracing side of the code, but the target/scsi
parts look ok to me.
Reviewed-by: Mike Christie <michael.christie@xxxxxxxxxx>
