perf probe: Provide perf interface for uprobes

- Enhances perf to probe user space executables and libraries.
- Enhances -F/--funcs option of "perf probe" to list possible probe points in
  an executable file or library.
- Documents userspace probing support in perf.

[ Probing a function in the executable using function name  ]
perf probe -x /bin/zsh zfree

[ Probing a library function using function name ]
perf probe -x /lib64/libc.so.6 malloc

[ list probe-able functions in an executable ]
perf probe -F -x /bin/zsh

[ list probe-able functions in an library]
perf probe -F -x /lib/libc.so.6

Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Anton Arapov <anton@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jim Keniston <jkenisto@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Linux-mm <linux-mm@kvack.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20120416120909.30661.99781.sendpatchset@srdronam.in.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/probe-event.h b/tools/perf/util/probe-event.h
index a7dee83..f9f3de8 100644
--- a/tools/perf/util/probe-event.h
+++ b/tools/perf/util/probe-event.h
@@ -7,7 +7,7 @@
 
 extern bool probe_event_dry_run;
 
-/* kprobe-tracer tracing point */
+/* kprobe-tracer and uprobe-tracer tracing point */
 struct probe_trace_point {
 	char		*symbol;	/* Base symbol */
 	char		*module;	/* Module name */
@@ -21,7 +21,7 @@
 	long				offset;	/* Offset value */
 };
 
-/* kprobe-tracer tracing argument */
+/* kprobe-tracer and uprobe-tracer tracing argument */
 struct probe_trace_arg {
 	char				*name;	/* Argument name */
 	char				*value;	/* Base value */
@@ -29,12 +29,13 @@
 	struct probe_trace_arg_ref	*ref;	/* Referencing offset */
 };
 
-/* kprobe-tracer tracing event (point + arg) */
+/* kprobe-tracer and uprobe-tracer tracing event (point + arg) */
 struct probe_trace_event {
 	char				*event;	/* Event name */
 	char				*group;	/* Group name */
 	struct probe_trace_point	point;	/* Trace point */
 	int				nargs;	/* Number of args */
+	bool				uprobes;	/* uprobes only */
 	struct probe_trace_arg		*args;	/* Arguments */
 };
 
@@ -70,6 +71,7 @@
 	char			*group;	/* Group name */
 	struct perf_probe_point	point;	/* Probe point */
 	int			nargs;	/* Number of arguments */
+	bool			uprobes;
 	struct perf_probe_arg	*args;	/* Arguments */
 };
 
@@ -129,8 +131,8 @@
 extern int show_available_vars(struct perf_probe_event *pevs, int npevs,
 			       int max_probe_points, const char *module,
 			       struct strfilter *filter, bool externs);
-extern int show_available_funcs(const char *module, struct strfilter *filter);
-
+extern int show_available_funcs(const char *module, struct strfilter *filter,
+				bool user);
 
 /* Maximum index number of event-name postfix */
 #define MAX_EVENT_INDEX	1024