[RFC PATCH 1/X] ptrace: tracehooks: do not use task->ptracedirectly

From: Oleg Nesterov
Date: Sun May 24 2009 - 20:04:52 EST


s/->ptrace/task_ptrace()/ in tracehook.h as a preparation for the future
changes.

Also, microoptimize tracehook_prepare_clone() for the common non-ptraced
case.

include/linux/tracehook.h | 16 +++++++++-------
1 file changed, 9 insertions(+), 7 deletions(-)

--- PTRACE/include/linux/tracehook.h~1_TRACEHOOK 2009-05-24 21:36:47.000000000 +0200
+++ PTRACE/include/linux/tracehook.h 2009-05-24 21:48:40.000000000 +0200
@@ -225,16 +225,18 @@ static inline void tracehook_report_exit
*/
static inline int tracehook_prepare_clone(unsigned clone_flags)
{
- if (clone_flags & CLONE_UNTRACED)
+ unsigned int ptrace = task_ptrace(current);
+
+ if (likely(!ptrace) || (clone_flags & CLONE_UNTRACED))
return 0;

if (clone_flags & CLONE_VFORK) {
- if (current->ptrace & PT_TRACE_VFORK)
+ if (ptrace & PT_TRACE_VFORK)
return PTRACE_EVENT_VFORK;
} else if ((clone_flags & CSIGNAL) != SIGCHLD) {
- if (current->ptrace & PT_TRACE_CLONE)
+ if (ptrace & PT_TRACE_CLONE)
return PTRACE_EVENT_CLONE;
- } else if (current->ptrace & PT_TRACE_FORK)
+ } else if (ptrace & PT_TRACE_FORK)
return PTRACE_EVENT_FORK;

return 0;
@@ -479,7 +481,7 @@ static inline int tracehook_get_signal(s
*/
static inline int tracehook_notify_jctl(int notify, int why)
{
- return notify || (current->ptrace & PT_PTRACED);
+ return notify || task_ptrace(current);
}

#define DEATH_REAP -1
@@ -503,7 +505,7 @@ static inline int tracehook_notify_death
void **death_cookie, int group_dead)
{
if (task_detached(task))
- return task->ptrace ? SIGCHLD : DEATH_REAP;
+ return task_ptrace(task) ? SIGCHLD : DEATH_REAP;

/*
* If something other than our normal parent is ptracing us, then
@@ -513,7 +515,7 @@ static inline int tracehook_notify_death
if (thread_group_empty(task) && !ptrace_reparented(task))
return task->exit_signal;

- return task->ptrace ? SIGCHLD : DEATH_DELAYED_GROUP_LEADER;
+ return task_ptrace(task) ? SIGCHLD : DEATH_DELAYED_GROUP_LEADER;
}

/**

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/