[PATCH v2 1/2] tools lib traceevent: Man page for tep_add_plugin_path() API
From: Tzvetomir Stoyanov (VMware)
Date: Wed Sep 30 2020 - 07:20:29 EST
Add documentation of tep_add_plugin_path() API in the libtraceevent
plugin man page.
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@xxxxxxxxx>
---
v2 changes:
- Fixed grammar mistakes, found by Steven Rostedt.
.../Documentation/libtraceevent-plugins.txt | 25 +++++++++++++++++--
1 file changed, 23 insertions(+), 2 deletions(-)
diff --git a/tools/lib/traceevent/Documentation/libtraceevent-plugins.txt b/tools/lib/traceevent/Documentation/libtraceevent-plugins.txt
index 4d6394397d92..4b7ac5c5217b 100644
--- a/tools/lib/traceevent/Documentation/libtraceevent-plugins.txt
+++ b/tools/lib/traceevent/Documentation/libtraceevent-plugins.txt
@@ -3,7 +3,7 @@ libtraceevent(3)
NAME
----
-tep_load_plugins, tep_unload_plugins, tep_load_plugins_hook - Load / unload traceevent plugins.
+tep_load_plugins, tep_unload_plugins, tep_load_plugins_hook, tep_add_plugin_path - Load / unload traceevent plugins.
SYNOPSIS
--------
@@ -19,6 +19,8 @@ void *tep_load_plugins_hook*(struct tep_handle pass:[*]_tep_, const char pass:[*
const char pass:[*]name,
void pass:[*]data),
void pass:[*]_data_);
+int *tep_add_plugin_path*(struct tep_handle pass:[*]tep, char pass:[*]path,
+ enum tep_plugin_load_priority prio);
--
DESCRIPTION
@@ -52,16 +54,33 @@ _tep_load_plugins()_. The _tep_ argument is trace event parser context. The
_plugin_list_ is the list of loaded plugins, returned by
the _tep_load_plugins()_ function.
-The _tep_load_plugins_hook_ function walks through all directories with plugins
+The _tep_load_plugins_hook()_ function walks through all directories with plugins
and calls user specified _load_plugin()_ hook for each plugin file. Only files
with given _suffix_ are considered to be plugins. The _data_ is a user specified
context, passed to _load_plugin()_. Directories and the walk order are the same
as in _tep_load_plugins()_ API.
+The _tep_add_plugin_path()_ functions adds additional directories with plugins in
+the _tep_->plugins_dir list. It must be called before _tep_load_plugins()_ in order
+for the plugins from the new directories to be loaded. The _tep_ argument is
+the trace event parser context. The _path_ is the full path to the new plugin
+directory. The _prio_ argument specifies the loading priority order for the
+new directory of plugins. The loading priority is important in case of different
+versions of the same plugin located in multiple plugin directories.The last loaded
+plugin wins. The priority can be:
+[verse]
+--
+ _TEP_PLUGIN_FIRST_ - Load plugins from this directory first
+ _TEP_PLUGIN_LAST_ - Load plugins from this directory last
+--
+Where the plugins in TEP_PLUGIN_LAST" will take precedence over the
+plugins in the other directories.
+
RETURN VALUE
------------
The _tep_load_plugins()_ function returns a list of successfully loaded plugins,
or NULL in case no plugins are loaded.
+The _tep_add_plugin_path()_ function returns -1 in case of an error, 0 otherwise.
EXAMPLE
-------
@@ -71,6 +90,8 @@ EXAMPLE
...
struct tep_handle *tep = tep_alloc();
...
+tep_add_plugin_path(tep, "~/dev_plugins", TEP_PLUGIN_LAST);
+...
struct tep_plugin_list *plugins = tep_load_plugins(tep);
if (plugins == NULL) {
/* no plugins are loaded */
--
2.26.2