tipc: Prune down link-specific debugging code

Eliminates most link-specific debugging code in TIPC, which is now
largely unnecessary. All calls to the link-specific debugging macros
have been removed, as are the macros themselves; in addition, the optional
allocation of print buffers to hold debugging information for each link
endpoint has been removed. The ability for TIPC to print out helpful
diagnostic information when link retransmit failures occur has been
retained for the time being, as an aid in tracking down the cause of
such failures.

Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 36 insertions, 147 deletions

diff --git a/net/tipc/bcast.c b/net/tipc/bcast.c
index cb817d503c14..22a10fadc8c6 100644
--- a/net/tipc/bcast.c
+++ b/net/tipc/bcast.c
@@ -45,8 +45,6 @@
 
 #define BCLINK_WIN_DEFAULT 20           /* bcast link window size (default) */
 
-#define BCLINK_LOG_BUF_SIZE 0
-
 /*
  * Loss rate for incoming broadcast frames; used to test retransmission code.
  * Set to N to cause every N'th frame to be discarded; 0 => don't discard any.
@@ -774,7 +772,6 @@ int tipc_bclink_init(void)
         bcbearer = kzalloc(sizeof(*bcbearer), GFP_ATOMIC);
         bclink = kzalloc(sizeof(*bclink), GFP_ATOMIC);
         if (!bcbearer || !bclink) {
- nomem:
                 warn("Multicast link creation failed, no memory\n");
                 kfree(bcbearer);
                 bcbearer = NULL;
@@ -799,14 +796,6 @@ int tipc_bclink_init(void)
         bcl->state = WORKING_WORKING;
         strlcpy(bcl->name, tipc_bclink_name, TIPC_MAX_LINK_NAME);
 
-        if (BCLINK_LOG_BUF_SIZE) {
-                char *pb = kmalloc(BCLINK_LOG_BUF_SIZE, GFP_ATOMIC);
-
-                if (!pb)
-                        goto nomem;
-                tipc_printbuf_init(&bcl->print_buf, pb, BCLINK_LOG_BUF_SIZE);
-        }
-
         return 0;
 }
 
@@ -815,8 +804,6 @@ void tipc_bclink_stop(void)
         spin_lock_bh(&bc_lock);
         if (bcbearer) {
                 tipc_link_stop(bcl);
-                if (BCLINK_LOG_BUF_SIZE)
-                        kfree(bcl->print_buf.buf);
                 bcl = NULL;
                 kfree(bclink);
                 bclink = NULL;
diff --git a/net/tipc/link.c b/net/tipc/link.c
index cb10d20caef3..647f2ecfde50 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -96,63 +96,10 @@ static int  link_send_sections_long(struct port *sender,
 static void link_check_defragm_bufs(struct link *l_ptr);
 static void link_state_event(struct link *l_ptr, u32 event);
 static void link_reset_statistics(struct link *l_ptr);
-static void link_print(struct link *l_ptr, struct print_buf *buf,
-                       const char *str);
+static void link_print(struct link *l_ptr, const char *str);
 static void link_start(struct link *l_ptr);
 static int link_send_long_buf(struct link *l_ptr, struct sk_buff *buf);
 
-
-/*
- * Debugging code used by link routines only
- *
- * When debugging link problems on a system that has multiple links,
- * the standard TIPC debugging routines may not be useful since they
- * allow the output from multiple links to be intermixed.  For this reason
- * routines of the form "dbg_link_XXX()" have been created that will capture
- * debug info into a link's personal print buffer, which can then be dumped
- * into the TIPC system log (TIPC_LOG) upon request.
- *
- * To enable per-link debugging, use LINK_LOG_BUF_SIZE to specify the size
- * of the print buffer used by each link.  If LINK_LOG_BUF_SIZE is set to 0,
- * the dbg_link_XXX() routines simply send their output to the standard
- * debug print buffer (DBG_OUTPUT), if it has been defined; this can be useful
- * when there is only a single link in the system being debugged.
- *
- * Notes:
- * - When enabled, LINK_LOG_BUF_SIZE should be set to at least TIPC_PB_MIN_SIZE
- * - "l_ptr" must be valid when using dbg_link_XXX() macros
- */
-
-#define LINK_LOG_BUF_SIZE 0
-
-#define dbg_link(fmt, arg...) \
-        do { \
-                if (LINK_LOG_BUF_SIZE) \
-                        tipc_printf(&l_ptr->print_buf, fmt, ## arg); \
-        } while (0)
-#define dbg_link_msg(msg, txt) \
-        do { \
-                if (LINK_LOG_BUF_SIZE) \
-                        tipc_msg_dbg(&l_ptr->print_buf, msg, txt); \
-        } while (0)
-#define dbg_link_state(txt) \
-        do { \
-                if (LINK_LOG_BUF_SIZE) \
-                        link_print(l_ptr, &l_ptr->print_buf, txt); \
-        } while (0)
-#define dbg_link_dump() do { \
-        if (LINK_LOG_BUF_SIZE) { \
-                tipc_printf(LOG, "\n\nDumping link <%s>:\n", l_ptr->name); \
-                tipc_printbuf_move(LOG, &l_ptr->print_buf); \
-        } \
-} while (0)
-
-static void dbg_print_link(struct link *l_ptr, const char *str)
-{
-        if (DBG_OUTPUT != TIPC_NULL)
-                link_print(l_ptr, DBG_OUTPUT, str);
-}
-
 /*
  *  Simple link routines
  */
@@ -366,17 +313,6 @@ struct link *tipc_link_create(struct bearer *b_ptr, const u32 peer,
                 return NULL;
         }
 
-        if (LINK_LOG_BUF_SIZE) {
-                char *pb = kmalloc(LINK_LOG_BUF_SIZE, GFP_ATOMIC);
-
-                if (!pb) {
-                        kfree(l_ptr);
-                        warn("Link creation failed, no memory for print buffer\n");
-                        return NULL;
-                }
-                tipc_printbuf_init(&l_ptr->print_buf, pb, LINK_LOG_BUF_SIZE);
-        }
-
         l_ptr->addr = peer;
         if_name = strchr(b_ptr->publ.name, ':') + 1;
         sprintf(l_ptr->name, "%u.%u.%u:%s-%u.%u.%u:",
@@ -411,8 +347,6 @@ struct link *tipc_link_create(struct bearer *b_ptr, const u32 peer,
 
         l_ptr->owner = tipc_node_attach_link(l_ptr);
         if (!l_ptr->owner) {
-                if (LINK_LOG_BUF_SIZE)
-                        kfree(l_ptr->print_buf.buf);
                 kfree(l_ptr);
                 return NULL;
         }
@@ -447,8 +381,6 @@ void tipc_link_delete(struct link *l_ptr)
         tipc_node_detach_link(l_ptr->owner, l_ptr);
         tipc_link_stop(l_ptr);
         list_del_init(&l_ptr->link_list);
-        if (LINK_LOG_BUF_SIZE)
-                kfree(l_ptr->print_buf.buf);
         tipc_node_unlock(l_ptr->owner);
         k_term_timer(&l_ptr->timer);
         kfree(l_ptr);
@@ -607,7 +539,6 @@ void tipc_link_reset(struct link *l_ptr)
         link_init_max_pkt(l_ptr);
 
         l_ptr->state = RESET_UNKNOWN;
-        dbg_link_state("Resetting Link\n");
 
         if ((prev_state == RESET_UNKNOWN) || (prev_state == RESET_RESET))
                 return;
@@ -686,20 +617,14 @@ static void link_state_event(struct link *l_ptr, unsigned event)
                 }
                 return;   /* Changeover going on */
         }
-        dbg_link("STATE_EV: <%s> ", l_ptr->name);
 
         switch (l_ptr->state) {
         case WORKING_WORKING:
-                dbg_link("WW/");
                 switch (event) {
                 case TRAFFIC_MSG_EVT:
-                        dbg_link("TRF-");
-                        /* fall through */
                 case ACTIVATE_MSG:
-                        dbg_link("ACT\n");
                         break;
                 case TIMEOUT_EVT:
-                        dbg_link("TIM ");
                         if (l_ptr->next_in_no != l_ptr->checkpoint) {
                                 l_ptr->checkpoint = l_ptr->next_in_no;
                                 if (tipc_bclink_acks_missing(l_ptr->owner)) {
@@ -714,7 +639,6 @@ static void link_state_event(struct link *l_ptr, unsigned event)
                                 link_set_timer(l_ptr, cont_intv);
                                 break;
                         }
-                        dbg_link(" -> WU\n");
                         l_ptr->state = WORKING_UNKNOWN;
                         l_ptr->fsm_msg_cnt = 0;
                         tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
@@ -722,7 +646,6 @@ static void link_state_event(struct link *l_ptr, unsigned event)
                         link_set_timer(l_ptr, cont_intv / 4);
                         break;
                 case RESET_MSG:
-                        dbg_link("RES -> RR\n");
                         info("Resetting link <%s>, requested by peer\n",
                              l_ptr->name);
                         tipc_link_reset(l_ptr);
@@ -737,18 +660,14 @@ static void link_state_event(struct link *l_ptr, unsigned event)
                 }
                 break;
         case WORKING_UNKNOWN:
-                dbg_link("WU/");
                 switch (event) {
                 case TRAFFIC_MSG_EVT:
-                        dbg_link("TRF-");
                 case ACTIVATE_MSG:
-                        dbg_link("ACT -> WW\n");
                         l_ptr->state = WORKING_WORKING;
                         l_ptr->fsm_msg_cnt = 0;
                         link_set_timer(l_ptr, cont_intv);
                         break;
                 case RESET_MSG:
-                        dbg_link("RES -> RR\n");
                         info("Resetting link <%s>, requested by peer "
                              "while probing\n", l_ptr->name);
                         tipc_link_reset(l_ptr);
@@ -759,9 +678,7 @@ static void link_state_event(struct link *l_ptr, unsigned event)
                         link_set_timer(l_ptr, cont_intv);
                         break;
                 case TIMEOUT_EVT:
-                        dbg_link("TIM ");
                         if (l_ptr->next_in_no != l_ptr->checkpoint) {
-                                dbg_link("-> WW\n");
                                 l_ptr->state = WORKING_WORKING;
                                 l_ptr->fsm_msg_cnt = 0;
                                 l_ptr->checkpoint = l_ptr->next_in_no;
@@ -772,16 +689,11 @@ static void link_state_event(struct link *l_ptr, unsigned event)
                                 }
                                 link_set_timer(l_ptr, cont_intv);
                         } else if (l_ptr->fsm_msg_cnt < l_ptr->abort_limit) {
-                                dbg_link("Probing %u/%u,timer = %u ms)\n",
-                                         l_ptr->fsm_msg_cnt, l_ptr->abort_limit,
-                                         cont_intv / 4);
                                 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
                                                          1, 0, 0, 0, 0);
                                 l_ptr->fsm_msg_cnt++;
                                 link_set_timer(l_ptr, cont_intv / 4);
                         } else {        /* Link has failed */
-                                dbg_link("-> RU (%u probes unanswered)\n",
-                                         l_ptr->fsm_msg_cnt);
                                 warn("Resetting link <%s>, peer not responding\n",
                                      l_ptr->name);
                                 tipc_link_reset(l_ptr);
@@ -798,18 +710,13 @@ static void link_state_event(struct link *l_ptr, unsigned event)
                 }
                 break;
         case RESET_UNKNOWN:
-                dbg_link("RU/");
                 switch (event) {
                 case TRAFFIC_MSG_EVT:
-                        dbg_link("TRF-\n");
                         break;
                 case ACTIVATE_MSG:
                         other = l_ptr->owner->active_links[0];
-                        if (other && link_working_unknown(other)) {
-                                dbg_link("ACT\n");
+                        if (other && link_working_unknown(other))
                                 break;
-                        }
-                        dbg_link("ACT -> WW\n");
                         l_ptr->state = WORKING_WORKING;
                         l_ptr->fsm_msg_cnt = 0;
                         link_activate(l_ptr);
@@ -818,8 +725,6 @@ static void link_state_event(struct link *l_ptr, unsigned event)
                         link_set_timer(l_ptr, cont_intv);
                         break;
                 case RESET_MSG:
-                        dbg_link("RES\n");
-                        dbg_link(" -> RR\n");
                         l_ptr->state = RESET_RESET;
                         l_ptr->fsm_msg_cnt = 0;
                         tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 1, 0, 0, 0, 0);
@@ -827,11 +732,9 @@ static void link_state_event(struct link *l_ptr, unsigned event)
                         link_set_timer(l_ptr, cont_intv);
                         break;
                 case STARTING_EVT:
-                        dbg_link("START-");
                         l_ptr->started = 1;
                         /* fall through */
                 case TIMEOUT_EVT:
-                        dbg_link("TIM\n");
                         tipc_link_send_proto_msg(l_ptr, RESET_MSG, 0, 0, 0, 0, 0);
                         l_ptr->fsm_msg_cnt++;
                         link_set_timer(l_ptr, cont_intv);
@@ -841,18 +744,12 @@ static void link_state_event(struct link *l_ptr, unsigned event)
                 }
                 break;
         case RESET_RESET:
-                dbg_link("RR/ ");
                 switch (event) {
                 case TRAFFIC_MSG_EVT:
-                        dbg_link("TRF-");
-                        /* fall through */
                 case ACTIVATE_MSG:
                         other = l_ptr->owner->active_links[0];
-                        if (other && link_working_unknown(other)) {
-                                dbg_link("ACT\n");
+                        if (other && link_working_unknown(other))
                                 break;
-                        }
-                        dbg_link("ACT -> WW\n");
                         l_ptr->state = WORKING_WORKING;
                         l_ptr->fsm_msg_cnt = 0;
                         link_activate(l_ptr);
@@ -861,14 +758,11 @@ static void link_state_event(struct link *l_ptr, unsigned event)
                         link_set_timer(l_ptr, cont_intv);
                         break;
                 case RESET_MSG:
-                        dbg_link("RES\n");
                         break;
                 case TIMEOUT_EVT:
-                        dbg_link("TIM\n");
                         tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0);
                         l_ptr->fsm_msg_cnt++;
                         link_set_timer(l_ptr, cont_intv);
-                        dbg_link("fsm_msg_cnt %u\n", l_ptr->fsm_msg_cnt);
                         break;
                 default:
                         err("Unknown link event %u in RR state\n", event);
@@ -1515,8 +1409,7 @@ static void link_reset_all(unsigned long addr)
 
         for (i = 0; i < MAX_BEARERS; i++) {
                 if (n_ptr->links[i]) {
-                        link_print(n_ptr->links[i], TIPC_OUTPUT,
-                                   "Resetting link\n");
+                        link_print(n_ptr->links[i], "Resetting link\n");
                         tipc_link_reset(n_ptr->links[i]);
                 }
         }
@@ -1535,7 +1428,7 @@ static void link_retransmit_failure(struct link *l_ptr, struct sk_buff *buf)
 
                 /* Handle failure on standard link */
 
-                link_print(l_ptr, TIPC_OUTPUT, "Resetting link\n");
+                link_print(l_ptr, "Resetting link\n");
                 tipc_link_reset(l_ptr);
 
         } else {
@@ -1545,21 +1438,21 @@ static void link_retransmit_failure(struct link *l_ptr, struct sk_buff *buf)
                 struct tipc_node *n_ptr;
                 char addr_string[16];
 
-                tipc_printf(TIPC_OUTPUT, "Msg seq number: %u,  ", msg_seqno(msg));
-                tipc_printf(TIPC_OUTPUT, "Outstanding acks: %lu\n",
-                                     (unsigned long) TIPC_SKB_CB(buf)->handle);
+                info("Msg seq number: %u,  ", msg_seqno(msg));
+                info("Outstanding acks: %lu\n",
+                     (unsigned long) TIPC_SKB_CB(buf)->handle);
 
                 n_ptr = l_ptr->owner->next;
                 tipc_node_lock(n_ptr);
 
                 tipc_addr_string_fill(addr_string, n_ptr->addr);
-                tipc_printf(TIPC_OUTPUT, "Multicast link info for %s\n", addr_string);
-                tipc_printf(TIPC_OUTPUT, "Supported: %d,  ", n_ptr->bclink.supported);
-                tipc_printf(TIPC_OUTPUT, "Acked: %u\n", n_ptr->bclink.acked);
-                tipc_printf(TIPC_OUTPUT, "Last in: %u,  ", n_ptr->bclink.last_in);
-                tipc_printf(TIPC_OUTPUT, "Gap after: %u,  ", n_ptr->bclink.gap_after);
-                tipc_printf(TIPC_OUTPUT, "Gap to: %u\n", n_ptr->bclink.gap_to);
-                tipc_printf(TIPC_OUTPUT, "Nack sync: %u\n\n", n_ptr->bclink.nack_sync);
+                info("Multicast link info for %s\n", addr_string);
+                info("Supported: %d,  ", n_ptr->bclink.supported);
+                info("Acked: %u\n", n_ptr->bclink.acked);
+                info("Last in: %u,  ", n_ptr->bclink.last_in);
+                info("Gap after: %u,  ", n_ptr->bclink.gap_after);
+                info("Gap to: %u\n", n_ptr->bclink.gap_to);
+                info("Nack sync: %u\n\n", n_ptr->bclink.nack_sync);
 
                 tipc_k_signal((Handler)link_reset_all, (unsigned long)n_ptr->addr);
 
@@ -1581,7 +1474,6 @@ void tipc_link_retransmit(struct link *l_ptr, struct sk_buff *buf,
 
         if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr)) {
                 if (l_ptr->retransm_queue_size == 0) {
-                        dbg_print_link(l_ptr, "   ");
                         l_ptr->retransm_queue_head = msg_seqno(msg);
                         l_ptr->retransm_queue_size = retransmits;
                 } else {
@@ -2458,7 +2350,6 @@ static int link_recv_changeover_msg(struct link **l_ptr,
         if (dest_link->exp_msg_count == 0) {
                 warn("Link switchover error, "
                      "got too many tunnelled messages\n");
-                dbg_print_link(dest_link, "LINK:");
                 goto exit;
         }
         dest_link->exp_msg_count--;
@@ -3066,14 +2957,22 @@ u32 tipc_link_get_max_pkt(u32 dest, u32 selector)
         return res;
 }
 
-static void link_print(struct link *l_ptr, struct print_buf *buf,
-                       const char *str)
+static void link_print(struct link *l_ptr, const char *str)
 {
+        char print_area[256];
+        struct print_buf pb;
+        struct print_buf *buf = &pb;
+
+        tipc_printbuf_init(buf, print_area, sizeof(print_area));
+
         tipc_printf(buf, str);
-        if (link_reset_reset(l_ptr) || link_reset_unknown(l_ptr))
-                return;
         tipc_printf(buf, "Link %x<%s>:",
                     l_ptr->addr, l_ptr->b_ptr->publ.name);
+
+#ifdef CONFIG_TIPC_DEBUG
+        if (link_reset_reset(l_ptr) || link_reset_unknown(l_ptr))
+                goto print_state;
+
         tipc_printf(buf, ": NXO(%u):", mod(l_ptr->next_out_no));
         tipc_printf(buf, "NXI(%u):", mod(l_ptr->next_in_no));
         tipc_printf(buf, "SQUE");
@@ -3104,14 +3003,20 @@ static void link_print(struct link *l_ptr, struct print_buf *buf,
                                     l_ptr->deferred_inqueue_sz);
                 }
         }
+print_state:
+#endif
+
         if (link_working_unknown(l_ptr))
                 tipc_printf(buf, ":WU");
-        if (link_reset_reset(l_ptr))
+        else if (link_reset_reset(l_ptr))
                 tipc_printf(buf, ":RR");
-        if (link_reset_unknown(l_ptr))
+        else if (link_reset_unknown(l_ptr))
                 tipc_printf(buf, ":RU");
-        if (link_working_working(l_ptr))
+        else if (link_working_working(l_ptr))
                 tipc_printf(buf, ":WW");
         tipc_printf(buf, "\n");
+
+        tipc_printbuf_validate(buf);
+        info("%s", print_area);
 }
 
diff --git a/net/tipc/link.h b/net/tipc/link.h
index eeb0c015dba9..eca19c247b79 100644
--- a/net/tipc/link.h
+++ b/net/tipc/link.h
@@ -107,7 +107,6 @@
  * @long_msg_seq_no: next identifier to use for outbound fragmented messages
  * @defragm_buf: list of partially reassembled inbound message fragments
  * @stats: collects statistics regarding link activity
- * @print_buf: print buffer used to log link activity
  */
 
 struct link {
@@ -210,8 +209,6 @@ struct link {
                 u32 msg_lengths_total;
                 u32 msg_length_profile[7];
         } stats;
-
-        struct print_buf print_buf;
 };
 
 struct port;