vlog: Make the most common module reference more direct.

Most vlog calls are for the log module owned by the translation unit being
compiled, but this module was referenced indirectly through a pointer
variable.  That seems silly, so this commit changes the code so that the
local vlog module is referred to directly, as &this_module.

We could get rid of the global variables for vlog modules entirely, but
I like getting linker errors when there's a duplicate module name.

Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Russell Bryant <russell@ovn.org>

include/openvswitch/vlog.h

@@ -170,46 +170,45 @@ void vlog_rate_limit(const struct vlog_module *, enum vlog_level,
                      struct vlog_rate_limit *, const char *, ...)
     OVS_PRINTF_FORMAT (4, 5);
 
-/* Creates and initializes a global instance of a module named MODULE, and
- * defines a static variable named THIS_MODULE that points to it, for use with
- * the convenience macros below. */
+/* Defines a logging module whose name is MODULE, which should generally be
+ * roughly the name of the source file, and makes it the module used by the
+ * logging convenience macros defined below. */
 #define VLOG_DEFINE_THIS_MODULE(MODULE)                                 \
-        /* This extra "extern" declaration makes sparse happy. */       \
-        extern struct vlog_module VLM_##MODULE;                         \
-        struct vlog_module VLM_##MODULE =                               \
-        {                                                               \
-            OVS_LIST_INITIALIZER(&VLM_##MODULE.list),                   \
+        static struct vlog_module this_module = {                       \
+            OVS_LIST_INITIALIZER(&this_module.list),                    \
             #MODULE,                                        /* name */  \
             { VLL_INFO, VLL_INFO, VLL_INFO },             /* levels */  \
             VLL_INFO,                                  /* min_level */  \
             true                               /* honor_rate_limits */  \
         };                                                              \
-        OVS_CONSTRUCTOR(init_##MODULE) {                                \
-                vlog_insert_module(&VLM_##MODULE.list);                 \
+        OVS_CONSTRUCTOR(init_this_module) {                             \
+            vlog_insert_module(&this_module.list);                      \
         }                                                               \
-        static struct vlog_module *const THIS_MODULE = &VLM_##MODULE
-
-/* Convenience macros.  These assume that THIS_MODULE points to a "struct
- * vlog_module" for the current module, as set up by e.g. the
- * VLOG_DEFINE_THIS_MODULE macro above.
+                                                                        \
+        /* Prevent duplicate module names, via linker error.            \
+         * The extra "extern" declaration makes sparse happy. */        \
+        extern struct vlog_module *VLM_##MODULE;                        \
+        struct vlog_module *VLM_##MODULE = &this_module;
+
+/* Macros for the current module as set up by VLOG_DEFINE_THIS_MODULE.
+ * These are usually what you want to use.
  *
  * Guaranteed to preserve errno.
  */
-#define VLOG_FATAL(...) vlog_fatal(THIS_MODULE, __VA_ARGS__)
-#define VLOG_ABORT(...) vlog_abort(THIS_MODULE, __VA_ARGS__)
+#define VLOG_FATAL(...) vlog_fatal(&this_module, __VA_ARGS__)
+#define VLOG_ABORT(...) vlog_abort(&this_module, __VA_ARGS__)
 #define VLOG_EMER(...) VLOG(VLL_EMER, __VA_ARGS__)
 #define VLOG_ERR(...) VLOG(VLL_ERR, __VA_ARGS__)
 #define VLOG_WARN(...) VLOG(VLL_WARN, __VA_ARGS__)
 #define VLOG_INFO(...) VLOG(VLL_INFO, __VA_ARGS__)
 #define VLOG_DBG(...) VLOG(VLL_DBG, __VA_ARGS__)
 
-/* More convenience macros, for testing whether a given level is enabled in
- * THIS_MODULE.  When constructing a log message is expensive, this enables it
- * to be skipped. */
-#define VLOG_IS_ERR_ENABLED() vlog_is_enabled(THIS_MODULE, VLL_ERR)
-#define VLOG_IS_WARN_ENABLED() vlog_is_enabled(THIS_MODULE, VLL_WARN)
-#define VLOG_IS_INFO_ENABLED() vlog_is_enabled(THIS_MODULE, VLL_INFO)
-#define VLOG_IS_DBG_ENABLED() vlog_is_enabled(THIS_MODULE, VLL_DBG)
+/* More convenience macros, for testing whether a given level is enabled.  When
+ * constructing a log message is expensive, this enables it to be skipped. */
+#define VLOG_IS_ERR_ENABLED() vlog_is_enabled(&this_module, VLL_ERR)
+#define VLOG_IS_WARN_ENABLED() vlog_is_enabled(&this_module, VLL_WARN)
+#define VLOG_IS_INFO_ENABLED() vlog_is_enabled(&this_module, VLL_INFO)
+#define VLOG_IS_DBG_ENABLED() vlog_is_enabled(&this_module, VLL_DBG)
 
 /* Convenience macros for rate-limiting.
  * Guaranteed to preserve errno.
@@ -224,10 +223,10 @@ void vlog_rate_limit(const struct vlog_module *, enum vlog_level,
 #define VLOG_ERR_BUF(ERRP, ...) VLOG_ERRP(ERRP, VLL_ERR, __VA_ARGS__)
 #define VLOG_WARN_BUF(ERRP, ...) VLOG_ERRP(ERRP, VLL_WARN, __VA_ARGS__)
 
-#define VLOG_DROP_ERR(RL) vlog_should_drop(THIS_MODULE, VLL_ERR, RL)
-#define VLOG_DROP_WARN(RL) vlog_should_drop(THIS_MODULE, VLL_WARN, RL)
-#define VLOG_DROP_INFO(RL) vlog_should_drop(THIS_MODULE, VLL_INFO, RL)
-#define VLOG_DROP_DBG(RL) vlog_should_drop(THIS_MODULE, VLL_DBG, RL)
+#define VLOG_DROP_ERR(RL) vlog_should_drop(&this_module, VLL_ERR, RL)
+#define VLOG_DROP_WARN(RL) vlog_should_drop(&this_module, VLL_WARN, RL)
+#define VLOG_DROP_INFO(RL) vlog_should_drop(&this_module, VLL_INFO, RL)
+#define VLOG_DROP_DBG(RL) vlog_should_drop(&this_module, VLL_DBG, RL)
 
 /* Macros for logging at most once per execution. */
 #define VLOG_ERR_ONCE(...) VLOG_ONCE(VLL_ERR, __VA_ARGS__)
@@ -267,22 +266,22 @@ void vlog_usage(void);
 #define VLOG(LEVEL, ...)                                \
     do {                                                \
         enum vlog_level level__ = LEVEL;                \
-        if (THIS_MODULE->min_level >= level__) {        \
-            vlog(THIS_MODULE, level__, __VA_ARGS__);    \
+        if (this_module.min_level >= level__) {         \
+            vlog(&this_module, level__, __VA_ARGS__);   \
         }                                               \
     } while (0)
-#define VLOG_RL(RL, LEVEL, ...)                                     \
-    do {                                                            \
-        enum vlog_level level__ = LEVEL;                            \
-        if (THIS_MODULE->min_level >= level__) {                    \
-            vlog_rate_limit(THIS_MODULE, level__, RL, __VA_ARGS__); \
-        }                                                           \
+#define VLOG_RL(RL, LEVEL, ...)                                         \
+    do {                                                                \
+        enum vlog_level level__ = LEVEL;                                \
+        if (this_module.min_level >= level__) {                         \
+            vlog_rate_limit(&this_module, level__, RL, __VA_ARGS__);    \
+        }                                                               \
     } while (0)
 #define VLOG_ONCE(LEVEL, ...)                                           \
     do {                                                                \
         static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER; \
         if (ovsthread_once_start(&once)) {                              \
-            vlog(THIS_MODULE, LEVEL, __VA_ARGS__);                      \
+            vlog(&this_module, LEVEL, __VA_ARGS__);                     \
             ovsthread_once_done(&once);                                 \
         }                                                               \
     } while (0)

lib/bfd.c

@@ -1,4 +1,4 @@
-/* Copyright (c) 2013, 2014, 2015 Nicira, Inc.
+/* Copyright (c) 2013, 2014, 2015, 2016 Nicira, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -1073,7 +1073,7 @@ log_msg(enum vlog_level level, const struct msg *p, const char *message,
 {
     struct ds ds = DS_EMPTY_INITIALIZER;
 
-    if (vlog_should_drop(THIS_MODULE, level, &rl)) {
+    if (vlog_should_drop(&this_module, level, &rl)) {
         return;
     }
 

lib/db-ctl-base.c

@@ -1992,7 +1992,7 @@ ctl_fatal(const char *format, ...)
     message = xvasprintf(format, args);
     va_end(args);
 
-    vlog_set_levels(&VLM_db_ctl_base, VLF_CONSOLE, VLL_OFF);
+    vlog_set_levels(&this_module, VLF_CONSOLE, VLL_OFF);
     VLOG_ERR("%s", message);
     ovs_error(0, "%s", message);
     ctl_exit(EXIT_FAILURE);

lib/dpif.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015 Nicira, Inc.
+ * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016 Nicira, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -1583,7 +1583,7 @@ flow_message_log_level(int error)
 static bool
 should_log_flow_message(int error)
 {
-    return !vlog_should_drop(THIS_MODULE, flow_message_log_level(error),
+    return !vlog_should_drop(&this_module, flow_message_log_level(error),
                              error ? &error_rl : &dpmsg_rl);
 }
 
@@ -1616,7 +1616,7 @@ log_flow_message(const struct dpif *dpif, int error, const char *operation,
         ds_put_cstr(&ds, ", actions:");
         format_odp_actions(&ds, actions, actions_len);
     }
-    vlog(THIS_MODULE, flow_message_log_level(error), "%s", ds_cstr(&ds));
+    vlog(&this_module, flow_message_log_level(error), "%s", ds_cstr(&ds));
     ds_destroy(&ds);
 }
 
@@ -1696,7 +1696,7 @@ log_execute_message(struct dpif *dpif, const struct dpif_execute *execute,
         }
         ds_put_format(&ds, " on packet %s", packet);
         ds_put_format(&ds, " mtu %d", execute->mtu);
-        vlog(THIS_MODULE, error ? VLL_WARN : VLL_DBG, "%s", ds_cstr(&ds));
+        vlog(&this_module, error ? VLL_WARN : VLL_DBG, "%s", ds_cstr(&ds));
         ds_destroy(&ds);
         free(packet);
     }

lib/jsonrpc.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2009, 2010, 2011, 2012, 2013, 2014, 2015 Nicira, Inc.
+ * Copyright (c) 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016 Nicira, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -343,7 +343,7 @@ jsonrpc_recv(struct jsonrpc *rpc, struct jsonrpc_msg **msgp)
                 const struct byteq *q = &rpc->input;
                 if (q->head <= q->size) {
                     stream_report_content(q->buffer, q->head, STREAM_JSONRPC,
-                                          THIS_MODULE, rpc->name);
+                                          &this_module, rpc->name);
                 }
                 return rpc->status;
             }

lib/ofp-prop.h

@@ -129,6 +129,6 @@ void ofpprop_end(struct ofpbuf *, size_t start_ofs);
 enum ofperr ofpprop_unknown(struct vlog_module *, bool loose, const char *msg,
                             uint64_t type);
 #define OFPPROP_UNKNOWN(LOOSE, MSG, TYPE) \
-    ofpprop_unknown(THIS_MODULE, LOOSE, MSG, TYPE)
+    ofpprop_unknown(&this_module, LOOSE, MSG, TYPE)
 
 #endif /* ofp-prop.h */

lib/stream-ssl.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015 Nicira, Inc.
+ * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016 Nicira, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -455,7 +455,7 @@ ssl_connect(struct stream *stream)
                                      : "SSL_accept"), retval, error, &unused);
                 shutdown(sslv->fd, SHUT_RDWR);
                 stream_report_content(sslv->head, sslv->n_head, STREAM_SSL,
-                                      THIS_MODULE, stream_get_name(stream));
+                                      &this_module, stream_get_name(stream));
                 return EPROTO;
             }
         } else if (bootstrap_ca_cert) {

lib/vconn-stream.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013 Nicira, Inc.
+ * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2016 Nicira, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -104,7 +104,7 @@ vconn_stream_close(struct vconn *vconn)
 
     if ((vconn->error == EPROTO || s->n_packets < 1) && s->rxbuf) {
         stream_report_content(s->rxbuf->data, s->rxbuf->size, STREAM_OPENFLOW,
-                              THIS_MODULE, vconn_get_name(vconn));
+                              &this_module, vconn_get_name(vconn));
     }
 
     stream_close(s->stream);

lib/vlog.c

@@ -209,7 +209,8 @@ vlog_get_destination_val(const char *name)
     return i;
 }
 
-void vlog_insert_module(struct ovs_list *vlog)
+void
+vlog_insert_module(struct ovs_list *vlog)
 {
     list_insert(&vlog_modules, vlog);
 }

ovn/utilities/ovn-nbctl.c

@@ -218,7 +218,7 @@ parse_options(int argc, char *argv[], struct shash *local_options)
             break;
 
         case OPT_NO_SYSLOG:
-            vlog_set_levels(&VLM_nbctl, VLF_SYSLOG, VLL_WARN);
+            vlog_set_levels(&this_module, VLF_SYSLOG, VLL_WARN);
             break;
 
         case OPT_DRY_RUN:

ovn/utilities/ovn-sbctl.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015 Nicira, Inc.
+ * Copyright (c) 2015, 2016 Nicira, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -231,7 +231,7 @@ parse_options(int argc, char *argv[], struct shash *local_options)
             break;
 
         case OPT_NO_SYSLOG:
-            vlog_set_levels(&VLM_sbctl, VLF_SYSLOG, VLL_WARN);
+            vlog_set_levels(&this_module, VLF_SYSLOG, VLL_WARN);
             break;
 
         case OPT_DRY_RUN:

tests/test-reconnect.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2009, 2010, 2011, 2012, 2014 Nicira, Inc.
+ * Copyright (c) 2009, 2010, 2011, 2012, 2014, 2016 Nicira, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.

utilities/ovs-vsctl.c

@@ -269,7 +269,7 @@ parse_options(int argc, char *argv[], struct shash *local_options)
             break;
 
         case OPT_NO_SYSLOG:
-            vlog_set_levels(&VLM_vsctl, VLF_SYSLOG, VLL_WARN);
+            vlog_set_levels(&this_module, VLF_SYSLOG, VLL_WARN);
             break;
 
         case OPT_NO_WAIT:

vtep/vtep-ctl.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2009, 2010, 2011, 2012, 2014, 2015 Nicira, Inc.
+ * Copyright (c) 2009, 2010, 2011, 2012, 2014, 2015, 2016 Nicira, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -223,7 +223,7 @@ parse_options(int argc, char *argv[], struct shash *local_options)
             break;
 
         case OPT_NO_SYSLOG:
-            vlog_set_levels(&VLM_vtep_ctl, VLF_SYSLOG, VLL_WARN);
+            vlog_set_levels(&this_module, VLF_SYSLOG, VLL_WARN);
             break;
 
         case OPT_DRY_RUN: