scsi: iscsi: Capture iscsi debug messages using tracepoints

This commit enhances iscsi initiator modules to capture iscsi debug
messages using linux kernel tracepoint facility:

https://www.kernel.org/doc/Documentation/trace/tracepoints.txt

The following tracepoint events have been created under the iscsi
tracepoint event group:

iscsi_dbg_conn - to capture connection debug messages (libiscsi module)

iscsi_dbg_session - to capture session debug messages (libiscsi module)

iscsi_dbg_eh - to capture error handling debug messages (libiscsi module)

iscsi_dbg_tcp - to capture iscsi tcp debug messages (libiscsi_tcp module)

iscsi_dbg_sw_tcp - to capture iscsi sw tcp debug messages (iscsi_tcp module)

iscsi_dbg_trans_session - to cpature iscsi transsport sess debug messages
	(scsi_transport_iscsi module)

iscsi_dbg_trans_conn - to capture iscsi transport conn debug messages
	(scsi_transport_iscsi module)

[mkp: typos]

Signed-off-by: Fred Herard <fred.herard@oracle.com>
Reviewed-by: Rajan Shanmugavelu <rajan.shanmugavelu@oracle.com>
Reviewed-by: Lee Duncan <lduncan@suse.com>
Reviewed-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Fred Herard 2018-11-21 12:04:43 -05:00 committed by Martin K. Petersen
parent 4c5765e485
commit c2332b0049
5 changed files with 158 additions and 1 deletions

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@ -44,6 +44,7 @@
#include <scsi/scsi_host.h>
#include <scsi/scsi.h>
#include <scsi/scsi_transport_iscsi.h>
#include <trace/events/iscsi.h>
#include "iscsi_tcp.h"
@ -72,6 +73,9 @@ MODULE_PARM_DESC(debug_iscsi_tcp, "Turn on debugging for iscsi_tcp module "
iscsi_conn_printk(KERN_INFO, _conn, \
"%s " dbg_fmt, \
__func__, ##arg); \
iscsi_dbg_trace(trace_iscsi_dbg_sw_tcp, \
&(_conn)->cls_conn->dev, \
"%s " dbg_fmt, __func__, ##arg);\
} while (0);

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@ -40,6 +40,7 @@
#include <scsi/scsi_transport.h>
#include <scsi/scsi_transport_iscsi.h>
#include <scsi/libiscsi.h>
#include <trace/events/iscsi.h>
static int iscsi_dbg_lib_conn;
module_param_named(debug_libiscsi_conn, iscsi_dbg_lib_conn, int,
@ -68,6 +69,9 @@ MODULE_PARM_DESC(debug_libiscsi_eh,
iscsi_conn_printk(KERN_INFO, _conn, \
"%s " dbg_fmt, \
__func__, ##arg); \
iscsi_dbg_trace(trace_iscsi_dbg_conn, \
&(_conn)->cls_conn->dev, \
"%s " dbg_fmt, __func__, ##arg);\
} while (0);
#define ISCSI_DBG_SESSION(_session, dbg_fmt, arg...) \
@ -76,6 +80,9 @@ MODULE_PARM_DESC(debug_libiscsi_eh,
iscsi_session_printk(KERN_INFO, _session, \
"%s " dbg_fmt, \
__func__, ##arg); \
iscsi_dbg_trace(trace_iscsi_dbg_session, \
&(_session)->cls_session->dev, \
"%s " dbg_fmt, __func__, ##arg); \
} while (0);
#define ISCSI_DBG_EH(_session, dbg_fmt, arg...) \
@ -84,6 +91,9 @@ MODULE_PARM_DESC(debug_libiscsi_eh,
iscsi_session_printk(KERN_INFO, _session, \
"%s " dbg_fmt, \
__func__, ##arg); \
iscsi_dbg_trace(trace_iscsi_dbg_eh, \
&(_session)->cls_session->dev, \
"%s " dbg_fmt, __func__, ##arg); \
} while (0);
inline void iscsi_conn_queue_work(struct iscsi_conn *conn)

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@ -43,6 +43,7 @@
#include <scsi/scsi_host.h>
#include <scsi/scsi.h>
#include <scsi/scsi_transport_iscsi.h>
#include <trace/events/iscsi.h>
#include "iscsi_tcp.h"
@ -65,6 +66,9 @@ MODULE_PARM_DESC(debug_libiscsi_tcp, "Turn on debugging for libiscsi_tcp "
iscsi_conn_printk(KERN_INFO, _conn, \
"%s " dbg_fmt, \
__func__, ##arg); \
iscsi_dbg_trace(trace_iscsi_dbg_tcp, \
&(_conn)->cls_conn->dev, \
"%s " dbg_fmt, __func__, ##arg);\
} while (0);
static int iscsi_tcp_hdr_recv_done(struct iscsi_tcp_conn *tcp_conn,

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@ -37,6 +37,18 @@
#define ISCSI_TRANSPORT_VERSION "2.0-870"
#define CREATE_TRACE_POINTS
#include <trace/events/iscsi.h>
/*
* Export tracepoint symbols to be used by other modules.
*/
EXPORT_TRACEPOINT_SYMBOL_GPL(iscsi_dbg_conn);
EXPORT_TRACEPOINT_SYMBOL_GPL(iscsi_dbg_eh);
EXPORT_TRACEPOINT_SYMBOL_GPL(iscsi_dbg_session);
EXPORT_TRACEPOINT_SYMBOL_GPL(iscsi_dbg_tcp);
EXPORT_TRACEPOINT_SYMBOL_GPL(iscsi_dbg_sw_tcp);
static int dbg_session;
module_param_named(debug_session, dbg_session, int,
S_IRUGO | S_IWUSR);
@ -59,6 +71,9 @@ MODULE_PARM_DESC(debug_conn,
iscsi_cls_session_printk(KERN_INFO, _session, \
"%s: " dbg_fmt, \
__func__, ##arg); \
iscsi_dbg_trace(trace_iscsi_dbg_trans_session, \
&(_session)->dev, \
"%s " dbg_fmt, __func__, ##arg); \
} while (0);
#define ISCSI_DBG_TRANS_CONN(_conn, dbg_fmt, arg...) \
@ -66,7 +81,10 @@ MODULE_PARM_DESC(debug_conn,
if (dbg_conn) \
iscsi_cls_conn_printk(KERN_INFO, _conn, \
"%s: " dbg_fmt, \
__func__, ##arg); \
__func__, ##arg); \
iscsi_dbg_trace(trace_iscsi_dbg_trans_conn, \
&(_conn)->dev, \
"%s " dbg_fmt, __func__, ##arg); \
} while (0);
struct iscsi_internal {
@ -4497,6 +4515,20 @@ int iscsi_unregister_transport(struct iscsi_transport *tt)
}
EXPORT_SYMBOL_GPL(iscsi_unregister_transport);
void iscsi_dbg_trace(void (*trace)(struct device *dev, struct va_format *),
struct device *dev, const char *fmt, ...)
{
struct va_format vaf;
va_list args;
va_start(args, fmt);
vaf.fmt = fmt;
vaf.va = &args;
trace(dev, &vaf);
va_end(args);
}
EXPORT_SYMBOL_GPL(iscsi_dbg_trace);
static __init int iscsi_transport_init(void)
{
int err;

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@ -0,0 +1,107 @@
#undef TRACE_SYSTEM
#define TRACE_SYSTEM iscsi
#if !defined(_TRACE_ISCSI_H) || defined(TRACE_HEADER_MULTI_READ)
#define _TRACE_ISCSI_H
#include <linux/tracepoint.h>
/* max debug message length */
#define ISCSI_MSG_MAX 256
/*
* Declare tracepoint helper function.
*/
void iscsi_dbg_trace(void (*trace)(struct device *dev, struct va_format *),
struct device *dev, const char *fmt, ...);
/*
* Declare event class for iscsi debug messages.
*/
DECLARE_EVENT_CLASS(iscsi_log_msg,
TP_PROTO(struct device *dev, struct va_format *vaf),
TP_ARGS(dev, vaf),
TP_STRUCT__entry(
__string(dname, dev_name(dev) )
__dynamic_array(char, msg, ISCSI_MSG_MAX )
),
TP_fast_assign(
__assign_str(dname, dev_name(dev));
vsnprintf(__get_str(msg), ISCSI_MSG_MAX, vaf->fmt, *vaf->va);
),
TP_printk("%s: %s",__get_str(dname), __get_str(msg)
)
);
/*
* Define event to capture iscsi connection debug messages.
*/
DEFINE_EVENT(iscsi_log_msg, iscsi_dbg_conn,
TP_PROTO(struct device *dev, struct va_format *vaf),
TP_ARGS(dev, vaf)
);
/*
* Define event to capture iscsi session debug messages.
*/
DEFINE_EVENT(iscsi_log_msg, iscsi_dbg_session,
TP_PROTO(struct device *dev, struct va_format *vaf),
TP_ARGS(dev, vaf)
);
/*
* Define event to capture iscsi error handling debug messages.
*/
DEFINE_EVENT(iscsi_log_msg, iscsi_dbg_eh,
TP_PROTO(struct device *dev, struct va_format *vaf),
TP_ARGS(dev, vaf)
);
/*
* Define event to capture iscsi tcp debug messages.
*/
DEFINE_EVENT(iscsi_log_msg, iscsi_dbg_tcp,
TP_PROTO(struct device *dev, struct va_format *vaf),
TP_ARGS(dev, vaf)
);
/*
* Define event to capture iscsi sw tcp debug messages.
*/
DEFINE_EVENT(iscsi_log_msg, iscsi_dbg_sw_tcp,
TP_PROTO(struct device *dev, struct va_format *vaf),
TP_ARGS(dev, vaf)
);
/*
* Define event to capture iscsi transport session debug messages.
*/
DEFINE_EVENT(iscsi_log_msg, iscsi_dbg_trans_session,
TP_PROTO(struct device *dev, struct va_format *vaf),
TP_ARGS(dev, vaf)
);
/*
* Define event to capture iscsi transport connection debug messages.
*/
DEFINE_EVENT(iscsi_log_msg, iscsi_dbg_trans_conn,
TP_PROTO(struct device *dev, struct va_format *vaf),
TP_ARGS(dev, vaf)
);
#endif /* _TRACE_ISCSI_H */
/* This part must be outside protection */
#include <trace/define_trace.h>