tracing: Restore system filter behavior
commit27b14b56af081ec7edeefb3a38b2c9577cc5ef48
authorLi Zefan <lizf@cn.fujitsu.com>
Tue, 1 Nov 2011 01:09:35 +0000 (1 09:09 +0800)
committerSteven Rostedt <rostedt@goodmis.org>
Mon, 5 Dec 2011 18:28:45 +0000 (5 13:28 -0500)
tree841e01c8d64fdf08b88c8a76de3272b4630ed145
parentcb59974742aea24adf6637eb0c4b8e7b48bca6fb
tracing: Restore system filter behavior

Though not all events have field 'prev_pid', it was allowed to do this:

  # echo 'prev_pid == 100' > events/sched/filter

but commit 75b8e98263fdb0bfbdeba60d4db463259f1fe8a2 (tracing/filter: Swap
entire filter of events) broke it without any reason.

Link: http://lkml.kernel.org/r/4EAF46CF.8040408@cn.fujitsu.com
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
include/linux/ftrace_event.h
kernel/trace/trace_events_filter.c