Commit 9eec21bf authored by Steve French's avatar Steve French
Browse files

smb3: add dynamic trace point to trace when credits obtained 



SMB3 crediting is used for flow control, and it can be useful to
trace for problem determination how many credits were acquired
and for which operation.

Here is an example ("trace-cmd record -e *add_credits"):
cifsd-9522    [010] ....  5995.202712: smb3_add_credits:
	server=localhost current_mid=0x12 credits=373 credits_to_add=10
cifsd-9522    [010] ....  5995.204040: smb3_add_credits:
	server=localhost current_mid=0x15 credits=400 credits_to_add=30

Reviewed-by: default avatarAurelien Aptel <aaptel@suse.com>
Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
parent acf96fef

fs/cifs/smb2ops.c

+3 −1
Original line number Diff line number Diff line
@@ -72,7 +72,7 @@ smb2_add_credits(struct TCP_Server_Info *server, 
	/* eg found case where write overlapping reconnect messed up credits */

	if (((optype & CIFS_OP_MASK) == CIFS_NEG_OP) && (*val != 0))

		trace_smb3_reconnect_with_invalid_credits(server->CurrentMid,

			server->hostname, *val);

			server->hostname, *val, add);

	if ((instance == 0) || (instance == server->reconnect_instance))

		*val += add;

	else
@@ -121,6 +121,8 @@ smb2_add_credits(struct TCP_Server_Info *server, 
		cifs_dbg(FYI, "disabling oplocks\n");

		break;

	default:

		trace_smb3_add_credits(server->CurrentMid,

			server->hostname, rc, add);

		cifs_dbg(FYI, "add %u credits total=%d\n", add, rc);

	}

}

fs/cifs/trace.h

+12 −6
Original line number Diff line number Diff line
@@ -878,33 +878,39 @@ DEFINE_SMB3_RECONNECT_EVENT(partial_send_reconnect); 
DECLARE_EVENT_CLASS(smb3_credit_class,

	TP_PROTO(__u64	currmid,

		char *hostname,

		int credits),

	TP_ARGS(currmid, hostname, credits),

		int credits,

		int credits_to_add),

	TP_ARGS(currmid, hostname, credits, credits_to_add),

	TP_STRUCT__entry(

		__field(__u64, currmid)

		__field(char *, hostname)

		__field(int, credits)

		__field(int, credits_to_add)

	),

	TP_fast_assign(

		__entry->currmid = currmid;

		__entry->hostname = hostname;

		__entry->credits = credits;

		__entry->credits_to_add = credits_to_add;

	),

	TP_printk("server=%s current_mid=0x%llx credits=%d",

	TP_printk("server=%s current_mid=0x%llx credits=%d credits_to_add=%d",

		__entry->hostname,

		__entry->currmid,

		__entry->credits)

		__entry->credits,

		__entry->credits_to_add)

)



#define DEFINE_SMB3_CREDIT_EVENT(name)        \

DEFINE_EVENT(smb3_credit_class, smb3_##name,  \

	TP_PROTO(__u64	currmid,		\

		char *hostname,			\

		int  credits),			\

	TP_ARGS(currmid, hostname, credits))

		int  credits,			\

		int  credits_to_add),		\

	TP_ARGS(currmid, hostname, credits, credits_to_add))



DEFINE_SMB3_CREDIT_EVENT(reconnect_with_invalid_credits);

DEFINE_SMB3_CREDIT_EVENT(credit_timeout);

DEFINE_SMB3_CREDIT_EVENT(add_credits);



#endif /* _CIFS_TRACE_H */

fs/cifs/transport.c

+3 −2
Original line number Diff line number Diff line
@@ -563,7 +563,7 @@ wait_for_free_credits(struct TCP_Server_Info *server, const int num_credits, 
			cifs_num_waiters_dec(server);

			if (!rc) {

				trace_smb3_credit_timeout(server->CurrentMid,

					server->hostname, num_credits);

					server->hostname, num_credits, 0);

				cifs_server_dbg(VFS, "wait timed out after %d ms\n",

					 timeout);

				return -ENOTSUPP;
@@ -604,7 +604,8 @@ wait_for_free_credits(struct TCP_Server_Info *server, const int num_credits, 
				if (!rc) {

					trace_smb3_credit_timeout(

						server->CurrentMid,

						server->hostname, num_credits);

						server->hostname, num_credits,

						0);

					cifs_server_dbg(VFS, "wait timed out after %d ms\n",

						 timeout);

					return -ENOTSUPP;

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