tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/Documentation/trace/kprobetrace.txt b/Documentation/trace/kprobetrace.txt
index a9100b2..ec94748 100644
--- a/Documentation/trace/kprobetrace.txt
+++ b/Documentation/trace/kprobetrace.txt
@@ -40,7 +40,9 @@
$stack : Fetch stack address.
$retval : Fetch return value.(*)
+|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address.(**)
- NAME=FETCHARG: Set NAME as the argument name of FETCHARG.
+ NAME=FETCHARG : Set NAME as the argument name of FETCHARG.
+ FETCHARG:TYPE : Set TYPE as the type of FETCHARG. Currently, basic types
+ (u8/u16/u32/u64/s8/s16/s32/s64) are supported.
(*) only for return probe.
(**) this is useful for fetching a field of data structures.