log: track log level changes

Add a log message when registering log types and changing log levels.

__rte_log_register previous handled both legacy and dynamic logtypes.
To simplify the code, __rte_log_register is reworked to only handle
dynamic logtypes and takes a log level.

Example:
$ DPDK_TEST=logs_autotest ./build/app/test/dpdk-test --no-huge -m 512 \
  --log-level=lib.eal:debug
...
RTE>>logs_autotest
== dynamic log types
EAL: logtype1 log level changed from disabled to info
EAL: logtype2 log level changed from disabled to info
EAL: logtype1 log level changed from info to error
EAL: logtype3 log level changed from error to emergency
EAL: logtype2 log level changed from info to emergency
EAL: logtype3 log level changed from emergency to debug
EAL: logtype1 log level changed from error to debug
EAL: logtype2 log level changed from emergency to debug
error message
critical message
critical message
error message
== static log types
TESTAPP1: error message
TESTAPP1: critical message
TESTAPP2: critical message
TESTAPP1: error message
Test OK

Suggested-by: Ilya Maximets <i.maximets@ovn.org>
Signed-off-by: David Marchand <david.marchand@redhat.com>
Acked-by: Andrew Rybchenko <arybchenko@solarflare.com>
Acked-by: Lukasz Wojciechowski <l.wojciechow@partner.samsung.com>
Acked-by: Thomas Monjalon <thomas@monjalon.net>

diff --git a/lib/librte_eal/common/eal_common_log.c b/lib/librte_eal/common/eal_common_log.c
index 4c1d514..bed83a4 100644 (file)
--- a/lib/librte_eal/common/eal_common_log.c
+++ b/lib/librte_eal/common/eal_common_log.c
@@ -135,6 +135,21 @@ rte_log_can_log(uint32_t logtype, uint32_t level)
        return true;
 }
 
+static void
+logtype_set_level(uint32_t type, uint32_t level)
+{
+       uint32_t current = rte_logs.dynamic_types[type].loglevel;
+
+       if (current != level) {
+               rte_logs.dynamic_types[type].loglevel = level;
+               RTE_LOG(DEBUG, EAL, "%s log level changed from %s to %s\n",
+                       rte_logs.dynamic_types[type].name == NULL ?
+                               "" : rte_logs.dynamic_types[type].name,
+                       eal_log_level2str(current),
+                       eal_log_level2str(level));
+       }
+}
+
 int
 rte_log_set_level(uint32_t type, uint32_t level)
 {
@@ -143,7 +158,7 @@ rte_log_set_level(uint32_t type, uint32_t level)
        if (level > RTE_LOG_MAX)
                return -1;
 
-       rte_logs.dynamic_types[type].loglevel = level;
+       logtype_set_level(type, level);
 
        return 0;
 }
@@ -166,7 +181,7 @@ rte_log_set_level_regexp(const char *regex, uint32_t level)
                        continue;
                if (regexec(&r, rte_logs.dynamic_types[i].name, 0,
                                NULL, 0) == 0)
-                       rte_logs.dynamic_types[i].loglevel = level;
+                       logtype_set_level(i, level);
        }
 
        regfree(&r);
@@ -227,7 +242,7 @@ rte_log_set_level_pattern(const char *pattern, uint32_t level)
                        continue;
 
                if (fnmatch(pattern, rte_logs.dynamic_types[i].name, 0) == 0)
-                       rte_logs.dynamic_types[i].loglevel = level;
+                       logtype_set_level(i, level);
        }
 
        return 0;
@@ -266,29 +281,11 @@ log_lookup(const char *name)
        return -1;
 }
 
-/* register an extended log type, assuming table is large enough, and id
- * is not yet registered.
- */
 static int
-log_register(const char *name, int id)
-{
-       char *dup_name = strdup(name);
-
-       if (dup_name == NULL)
-               return -ENOMEM;
-
-       rte_logs.dynamic_types[id].name = dup_name;
-       rte_logs.dynamic_types[id].loglevel = RTE_LOG_INFO;
-
-       return id;
-}
-
-/* register an extended log type */
-int
-rte_log_register(const char *name)
+log_register(const char *name, uint32_t level)
 {
        struct rte_log_dynamic_type *new_dynamic_types;
-       int id, ret;
+       int id;
 
        id = log_lookup(name);
        if (id >= 0)
@@ -301,13 +298,24 @@ rte_log_register(const char *name)
                return -ENOMEM;
        rte_logs.dynamic_types = new_dynamic_types;
 
-       ret = log_register(name, rte_logs.dynamic_types_len);
-       if (ret < 0)
-               return ret;
+       id = rte_logs.dynamic_types_len;
+       memset(&rte_logs.dynamic_types[id], 0,
+               sizeof(rte_logs.dynamic_types[id]));
+       rte_logs.dynamic_types[id].name = strdup(name);
+       if (rte_logs.dynamic_types[id].name == NULL)
+               return -ENOMEM;
+       logtype_set_level(id, level);
 
        rte_logs.dynamic_types_len++;
 
-       return ret;
+       return id;
+}
+
+/* register an extended log type */
+int
+rte_log_register(const char *name)
+{
+       return log_register(name, RTE_LOG_INFO);
 }
 
 /* Register an extended log type and try to pick its level from EAL options */
@@ -316,11 +324,6 @@ rte_log_register_type_and_pick_level(const char *name, uint32_t level_def)
 {
        struct rte_eal_opt_loglevel *opt_ll;
        uint32_t level = level_def;
-       int type;
-
-       type = rte_log_register(name);
-       if (type < 0)
-               return type;
 
        TAILQ_FOREACH(opt_ll, &opt_loglevel_list, next) {
                if (opt_ll->level > RTE_LOG_MAX)
@@ -335,9 +338,7 @@ rte_log_register_type_and_pick_level(const char *name, uint32_t level_def)
                }
        }
 
-       rte_logs.dynamic_types[type].loglevel = level;
-
-       return type;
+       return log_register(name, level);
 }
 
 struct logtype {
@@ -390,9 +391,11 @@ RTE_INIT_PRIO(log_init, LOG)
                return;
 
        /* register legacy log types */
-       for (i = 0; i < RTE_DIM(logtype_strings); i++)
-               log_register(logtype_strings[i].logtype,
-                               logtype_strings[i].log_id);
+       for (i = 0; i < RTE_DIM(logtype_strings); i++) {
+               rte_logs.dynamic_types[logtype_strings[i].log_id].name =
+                       strdup(logtype_strings[i].logtype);
+               logtype_set_level(logtype_strings[i].log_id, RTE_LOG_INFO);
+       }
 
        rte_logs.dynamic_types_len = RTE_LOGTYPE_FIRST_EXT_ID;
 }