From 63fbdab3157b72467013fe4dcf88c85e45280ef7 Mon Sep 17 00:00:00 2001 From: Jason Baron Date: Mon, 10 Aug 2009 16:52:27 -0400 Subject: tracing: Add DECLARE_TRACE_WITH_CALLBACK() macro Introduce a new 'DECLARE_TRACE_WITH_CALLBACK()' macro, so that tracepoints can associate an external register/unregister function. This prepares for the syscalls tracer conversion to trace events. We will need to perform arch level operations once a syscall event is turned on/off, such as TIF flags setting, hence the need of such specific callbacks. Signed-off-by: Jason Baron Cc: Lai Jiangshan Cc: Steven Rostedt Cc: Peter Zijlstra Cc: Mathieu Desnoyers Cc: Jiaying Zhang Cc: Martin Bligh Cc: Li Zefan Cc: Masami Hiramatsu Signed-off-by: Frederic Weisbecker --- include/linux/tracepoint.h | 31 +++++++++++++++++++++++++++---- 1 file changed, 27 insertions(+), 4 deletions(-) (limited to 'include/linux/tracepoint.h') diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h index b9dc4ca0246f..5984ed04c03b 100644 --- a/include/linux/tracepoint.h +++ b/include/linux/tracepoint.h @@ -60,8 +60,10 @@ struct tracepoint { * Make sure the alignment of the structure in the __tracepoints section will * not add unwanted padding between the beginning of the section and the * structure. Force alignment to the same alignment as the section start. + * An optional set of (un)registration functions can be passed to perform any + * additional (un)registration work. */ -#define DECLARE_TRACE(name, proto, args) \ +#define DECLARE_TRACE_WITH_CALLBACK(name, proto, args, reg, unreg) \ extern struct tracepoint __tracepoint_##name; \ static inline void trace_##name(proto) \ { \ @@ -71,13 +73,30 @@ struct tracepoint { } \ static inline int register_trace_##name(void (*probe)(proto)) \ { \ - return tracepoint_probe_register(#name, (void *)probe); \ + int ret; \ + void (*func)(void) = reg; \ + \ + ret = tracepoint_probe_register(#name, (void *)probe); \ + if (func && !ret) \ + func(); \ + return ret; \ } \ static inline int unregister_trace_##name(void (*probe)(proto)) \ { \ - return tracepoint_probe_unregister(#name, (void *)probe);\ + int ret; \ + void (*func)(void) = unreg; \ + \ + ret = tracepoint_probe_unregister(#name, (void *)probe);\ + if (func && !ret) \ + func(); \ + return ret; \ } + +#define DECLARE_TRACE(name, proto, args) \ + DECLARE_TRACE_WITH_CALLBACK(name, TP_PROTO(proto), TP_ARGS(args),\ + NULL, NULL); + #define DEFINE_TRACE(name) \ static const char __tpstrtab_##name[] \ __attribute__((section("__tracepoints_strings"))) = #name; \ @@ -94,7 +113,7 @@ extern void tracepoint_update_probe_range(struct tracepoint *begin, struct tracepoint *end); #else /* !CONFIG_TRACEPOINTS */ -#define DECLARE_TRACE(name, proto, args) \ +#define DECLARE_TRACE_WITH_CALLBACK(name, proto, args, reg, unreg) \ static inline void _do_trace_##name(struct tracepoint *tp, proto) \ { } \ static inline void trace_##name(proto) \ @@ -108,6 +127,10 @@ extern void tracepoint_update_probe_range(struct tracepoint *begin, return -ENOSYS; \ } +#define DECLARE_TRACE(name, proto, args) \ + DECLARE_TRACE_WITH_CALLBACK(name, TP_PROTO(proto), TP_ARGS(args),\ + NULL, NULL); + #define DEFINE_TRACE(name) #define EXPORT_TRACEPOINT_SYMBOL_GPL(name) #define EXPORT_TRACEPOINT_SYMBOL(name) -- cgit v1.2.3 From 97419875865859fd2403e66266c02ce028e2f5ab Mon Sep 17 00:00:00 2001 From: Josh Stone Date: Mon, 24 Aug 2009 14:43:13 -0700 Subject: tracing: Move tracepoint callbacks from declaration to definition It's not strictly correct for the tracepoint reg/unreg callbacks to occur when a client is hooking up, because the actual tracepoint may not be present yet. This happens to be fine for syscall, since that's in the core kernel, but it would cause problems for tracepoints defined in a module that hasn't been loaded yet. It also means the reg/unreg has to be EXPORTed for any modules to use the tracepoint (as in SystemTap). This patch removes DECLARE_TRACE_WITH_CALLBACK, and instead introduces DEFINE_TRACE_FN which stores the callbacks in struct tracepoint. The callbacks are used now when the active state of the tracepoint changes in set_tracepoint & disable_tracepoint. This also introduces TRACE_EVENT_FN, so ftrace events can also provide registration callbacks if needed. Signed-off-by: Josh Stone Cc: Jason Baron Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Li Zefan Cc: Steven Rostedt Cc: Peter Zijlstra Cc: Mathieu Desnoyers Cc: Jiaying Zhang Cc: Martin Bligh Cc: Lai Jiangshan Cc: Paul Mundt Cc: Martin Schwidefsky Cc: Heiko Carstens LKML-Reference: <1251150194-1713-4-git-send-email-jistone@redhat.com> Signed-off-by: Frederic Weisbecker --- include/linux/tracepoint.h | 46 ++++++++++++++++++---------------------------- 1 file changed, 18 insertions(+), 28 deletions(-) (limited to 'include/linux/tracepoint.h') diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h index 5984ed04c03b..846a4ae501eb 100644 --- a/include/linux/tracepoint.h +++ b/include/linux/tracepoint.h @@ -23,6 +23,8 @@ struct tracepoint; struct tracepoint { const char *name; /* Tracepoint name */ int state; /* State. */ + void (*regfunc)(void); + void (*unregfunc)(void); void **funcs; } __attribute__((aligned(32))); /* * Aligned on 32 bytes because it is @@ -60,10 +62,8 @@ struct tracepoint { * Make sure the alignment of the structure in the __tracepoints section will * not add unwanted padding between the beginning of the section and the * structure. Force alignment to the same alignment as the section start. - * An optional set of (un)registration functions can be passed to perform any - * additional (un)registration work. */ -#define DECLARE_TRACE_WITH_CALLBACK(name, proto, args, reg, unreg) \ +#define DECLARE_TRACE(name, proto, args) \ extern struct tracepoint __tracepoint_##name; \ static inline void trace_##name(proto) \ { \ @@ -73,36 +73,23 @@ struct tracepoint { } \ static inline int register_trace_##name(void (*probe)(proto)) \ { \ - int ret; \ - void (*func)(void) = reg; \ - \ - ret = tracepoint_probe_register(#name, (void *)probe); \ - if (func && !ret) \ - func(); \ - return ret; \ + return tracepoint_probe_register(#name, (void *)probe); \ } \ static inline int unregister_trace_##name(void (*probe)(proto)) \ { \ - int ret; \ - void (*func)(void) = unreg; \ - \ - ret = tracepoint_probe_unregister(#name, (void *)probe);\ - if (func && !ret) \ - func(); \ - return ret; \ + return tracepoint_probe_unregister(#name, (void *)probe);\ } -#define DECLARE_TRACE(name, proto, args) \ - DECLARE_TRACE_WITH_CALLBACK(name, TP_PROTO(proto), TP_ARGS(args),\ - NULL, NULL); - -#define DEFINE_TRACE(name) \ +#define DEFINE_TRACE_FN(name, reg, unreg) \ static const char __tpstrtab_##name[] \ __attribute__((section("__tracepoints_strings"))) = #name; \ struct tracepoint __tracepoint_##name \ __attribute__((section("__tracepoints"), aligned(32))) = \ - { __tpstrtab_##name, 0, NULL } + { __tpstrtab_##name, 0, reg, unreg, NULL } + +#define DEFINE_TRACE(name) \ + DEFINE_TRACE_FN(name, NULL, NULL); #define EXPORT_TRACEPOINT_SYMBOL_GPL(name) \ EXPORT_SYMBOL_GPL(__tracepoint_##name) @@ -113,7 +100,7 @@ extern void tracepoint_update_probe_range(struct tracepoint *begin, struct tracepoint *end); #else /* !CONFIG_TRACEPOINTS */ -#define DECLARE_TRACE_WITH_CALLBACK(name, proto, args, reg, unreg) \ +#define DECLARE_TRACE(name, proto, args) \ static inline void _do_trace_##name(struct tracepoint *tp, proto) \ { } \ static inline void trace_##name(proto) \ @@ -127,10 +114,7 @@ extern void tracepoint_update_probe_range(struct tracepoint *begin, return -ENOSYS; \ } -#define DECLARE_TRACE(name, proto, args) \ - DECLARE_TRACE_WITH_CALLBACK(name, TP_PROTO(proto), TP_ARGS(args),\ - NULL, NULL); - +#define DEFINE_TRACE_FN(name, reg, unreg) #define DEFINE_TRACE(name) #define EXPORT_TRACEPOINT_SYMBOL_GPL(name) #define EXPORT_TRACEPOINT_SYMBOL(name) @@ -282,10 +266,16 @@ static inline void tracepoint_synchronize_unregister(void) * can also by used by generic instrumentation like SystemTap), and * it is also used to expose a structured trace record in * /sys/kernel/debug/tracing/events/. + * + * A set of (un)registration functions can be passed to the variant + * TRACE_EVENT_FN to perform any (un)registration work. */ #define TRACE_EVENT(name, proto, args, struct, assign, print) \ DECLARE_TRACE(name, PARAMS(proto), PARAMS(args)) +#define TRACE_EVENT_FN(name, proto, args, struct, \ + assign, print, reg, unreg) \ + DECLARE_TRACE(name, PARAMS(proto), PARAMS(args)) #endif #endif -- cgit v1.2.3 From 5ac35daa9343936038a3c9c4f4d6d3fe6a2a7bd8 Mon Sep 17 00:00:00 2001 From: Xiao Guangrong Date: Tue, 25 Aug 2009 14:06:22 +0800 Subject: tracing/events: fix the include file dependencies The TRACE_EVENT depends on the include/linux/tracepoint.h first and include/trace/ftrace.h later, if we include the ftrace.h early, a building error will occur. Both define TRACE_EVENT in trace_a.h and trace_b.h, if we include those in .c file, like this: #define CREATE_TRACE_POINTS include include The above will not work, because the TRACE_EVENT was re-defined by the previous .h file. Reported-by: Wei Yongjun Signed-off-by: Xiao Guangrong LKML-Reference: <4A937F5E.3020802@cn.fujitsu.com> Signed-off-by: Steven Rostedt --- include/linux/tracepoint.h | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'include/linux/tracepoint.h') diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h index 5984ed04c03b..81709854f7ab 100644 --- a/include/linux/tracepoint.h +++ b/include/linux/tracepoint.h @@ -180,6 +180,7 @@ static inline void tracepoint_synchronize_unregister(void) } #define PARAMS(args...) args +#endif #ifndef TRACE_EVENT /* @@ -287,5 +288,3 @@ static inline void tracepoint_synchronize_unregister(void) #define TRACE_EVENT(name, proto, args, struct, assign, print) \ DECLARE_TRACE(name, PARAMS(proto), PARAMS(args)) #endif - -#endif -- cgit v1.2.3 From 7cb2e3ee2aeec5b83ecadba929a2dc575dd4008f Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 26 Aug 2009 00:32:37 -0400 Subject: tracing: add comments to explain TRACE_EVENT out of protection The commit: commit 5ac35daa9343936038a3c9c4f4d6d3fe6a2a7bd8 Author: Xiao Guangrong tracing/events: fix the include file dependencies Moved the TRACE_EVENT out of the ifdef protection of tracepoints.h but uses the define of TRACE_EVENT itself as protection. This patch adds comments to explain why. Signed-off-by: Steven Rostedt --- include/linux/tracepoint.h | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) (limited to 'include/linux/tracepoint.h') diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h index 81709854f7ab..0341f2e2698a 100644 --- a/include/linux/tracepoint.h +++ b/include/linux/tracepoint.h @@ -180,7 +180,15 @@ static inline void tracepoint_synchronize_unregister(void) } #define PARAMS(args...) args -#endif + +#endif /* _LINUX_TRACEPOINT_H */ + +/* + * Note: we keep the TRACE_EVENT outside the include file ifdef protection. + * This is due to the way trace events work. If a file includes two + * trace event headers under one "CREATE_TRACE_POINTS" the first include + * will override the TRACE_EVENT and break the second include. + */ #ifndef TRACE_EVENT /* @@ -287,4 +295,5 @@ static inline void tracepoint_synchronize_unregister(void) #define TRACE_EVENT(name, proto, args, struct, assign, print) \ DECLARE_TRACE(name, PARAMS(proto), PARAMS(args)) -#endif + +#endif /* ifdef TRACE_EVENT (see note above) */ -- cgit v1.2.3