tracepoint: Use struct pointer instead of name hash for reg/unreg tracepoints
Register/unregister tracepoint probes with struct tracepoint pointer
rather than tracepoint name.
This change, which vastly simplifies tracepoint.c, has been proposed by
Steven Rostedt. It also removes 8.8kB (mostly of text) to the vmlinux
size.
From this point on, the tracers need to pass a struct tracepoint pointer
to probe register/unregister. A probe can now only be connected to a
tracepoint that exists. Moreover, tracers are responsible for
unregistering the probe before the module containing its associated
tracepoint is unloaded.
text data bss dec hex filename
10443444 4282528 10391552 25117524 17f4354 vmlinux.orig
10434930 4282848 10391552 25109330 17f2352 vmlinux
Link: http://lkml.kernel.org/r/1396992381-23785-2-git-send-email-mathieu.desnoyers@efficios.com
CC: Ingo Molnar <mingo@kernel.org>
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Frank Ch. Eigler <fche@redhat.com>
CC: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
[ SDR - fixed return val in void func in tracepoint_module_going() ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h
index 812b255..08150e2 100644
--- a/include/linux/tracepoint.h
+++ b/include/linux/tracepoint.h
@@ -6,7 +6,7 @@
*
* See Documentation/trace/tracepoints.txt.
*
- * (C) Copyright 2008 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
+ * Copyright (C) 2008-2014 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
*
* Heavily inspired from the Linux Kernel Markers.
*
@@ -21,6 +21,7 @@
struct module;
struct tracepoint;
+struct notifier_block;
struct tracepoint_func {
void *func;
@@ -35,18 +36,13 @@
struct tracepoint_func __rcu *funcs;
};
-/*
- * Connect a probe to a tracepoint.
- * Internal API, should not be used directly.
- */
-extern int tracepoint_probe_register(const char *name, void *probe, void *data);
-
-/*
- * Disconnect a probe from a tracepoint.
- * Internal API, should not be used directly.
- */
extern int
-tracepoint_probe_unregister(const char *name, void *probe, void *data);
+tracepoint_probe_register(struct tracepoint *tp, void *probe, void *data);
+extern int
+tracepoint_probe_unregister(struct tracepoint *tp, void *probe, void *data);
+extern void
+for_each_kernel_tracepoint(void (*fct)(struct tracepoint *tp, void *priv),
+ void *priv);
#ifdef CONFIG_MODULES
struct tp_module {
@@ -54,12 +50,25 @@
unsigned int num_tracepoints;
struct tracepoint * const *tracepoints_ptrs;
};
+
bool trace_module_has_bad_taint(struct module *mod);
+extern int register_tracepoint_module_notifier(struct notifier_block *nb);
+extern int unregister_tracepoint_module_notifier(struct notifier_block *nb);
#else
static inline bool trace_module_has_bad_taint(struct module *mod)
{
return false;
}
+static inline
+int register_tracepoint_module_notifier(struct notifier_block *nb)
+{
+ return 0;
+}
+static inline
+int unregister_tracepoint_module_notifier(struct notifier_block *nb)
+{
+ return 0;
+}
#endif /* CONFIG_MODULES */
/*
@@ -160,14 +169,14 @@
static inline int \
register_trace_##name(void (*probe)(data_proto), void *data) \
{ \
- return tracepoint_probe_register(#name, (void *)probe, \
- data); \
+ return tracepoint_probe_register(&__tracepoint_##name, \
+ (void *)probe, data); \
} \
static inline int \
unregister_trace_##name(void (*probe)(data_proto), void *data) \
{ \
- return tracepoint_probe_unregister(#name, (void *)probe, \
- data); \
+ return tracepoint_probe_unregister(&__tracepoint_##name,\
+ (void *)probe, data); \
} \
static inline void \
check_trace_callback_type_##name(void (*cb)(data_proto)) \