tracing/kprobes: Add bitfield type
authorMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Fri, 4 Feb 2011 12:52:05 +0000 (21:52 +0900)
committerArnaldo Carvalho de Melo <acme@redhat.com>
Mon, 7 Feb 2011 11:18:11 +0000 (09:18 -0200)
commit1ff511e35ed87cc2ebade9e678e4a2fe39b6f9c5
treeb16cff475673db75aef773cc1118734a2172066a
parente3745369986ddcdaa19f70e2d24e658876b97e84
tracing/kprobes: Add bitfield type

Add bitfield type for tracing arguments on kprobe-tracer.  The syntax of
a bitfield type is:

 b<bit-size>@<bit-offset>/<container-size>

e.g.

Accessing 2 bits-width field with 4 bits-offset in 32 bits-width data at
4 bytes offseted from the address pointed by AX register:

 +4(%ax):b2@4/32

Since the width of container data depends on the arch, so I just added
the container-size at the end.

Cc: 2nddept-manager@sdl.hitachi.co.jp
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <20110204125205.9507.11363.stgit@ltc236.sdl.hitachi.co.jp>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Documentation/trace/kprobetrace.txt
kernel/trace/trace_kprobe.c