diff options
author | Oleg Nesterov <oleg@redhat.com> | 2014-12-10 15:55:14 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-12-10 17:41:17 -0800 |
commit | c9dc05bfdb3f7fd7c00f3cbd33816c99d2cb9029 (patch) | |
tree | 2b1f69634ca760afbb4585d5a6a37bc549cd5c7c /kernel/exit.c | |
parent | 1109909c7df08f55ff9104276bb9db1ee2e6e53d (diff) | |
download | linux-c9dc05bfdb3f7fd7c00f3cbd33816c99d2cb9029.tar.gz linux-c9dc05bfdb3f7fd7c00f3cbd33816c99d2cb9029.tar.bz2 linux-c9dc05bfdb3f7fd7c00f3cbd33816c99d2cb9029.zip |
exit: reparent: introduce find_alive_thread()
Add the new simple helper to factor out the for_each_thread() code in
find_child_reaper() and find_new_reaper(). It can also simplify the
potential PF_EXITING -> exit_state change, plus perhaps we can change this
code to take SIGNAL_GROUP_EXIT into account.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Kay Sievers <kay@vrfy.org>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Sterling Alexander <stalexan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/exit.c')
-rw-r--r-- | kernel/exit.c | 32 |
1 files changed, 19 insertions, 13 deletions
diff --git a/kernel/exit.c b/kernel/exit.c index 930fbe1b5ee2..b0f482f5daf9 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -459,6 +459,17 @@ static void exit_mm(struct task_struct *tsk) clear_thread_flag(TIF_MEMDIE); } +static struct task_struct *find_alive_thread(struct task_struct *p) +{ + struct task_struct *t; + + for_each_thread(p, t) { + if (!(t->flags & PF_EXITING)) + return t; + } + return NULL; +} + static struct task_struct *find_child_reaper(struct task_struct *father) __releases(&tasklist_lock) __acquires(&tasklist_lock) @@ -469,9 +480,8 @@ static struct task_struct *find_child_reaper(struct task_struct *father) if (likely(reaper != father)) return reaper; - for_each_thread(father, reaper) { - if (reaper->flags & PF_EXITING) - continue; + reaper = find_alive_thread(father); + if (reaper) { pid_ns->child_reaper = reaper; return reaper; } @@ -497,16 +507,13 @@ static struct task_struct *find_child_reaper(struct task_struct *father) static struct task_struct *find_new_reaper(struct task_struct *father, struct task_struct *child_reaper) { - struct task_struct *thread; + struct task_struct *thread, *reaper; - for_each_thread(father, thread) { - if (thread->flags & PF_EXITING) - continue; + thread = find_alive_thread(father); + if (thread) return thread; - } if (father->signal->has_child_subreaper) { - struct task_struct *reaper; /* * Find the first ->is_child_subreaper ancestor in our pid_ns. * We start from father to ensure we can not look into another @@ -520,10 +527,9 @@ static struct task_struct *find_new_reaper(struct task_struct *father, break; if (!reaper->signal->is_child_subreaper) continue; - for_each_thread(reaper, thread) { - if (!(thread->flags & PF_EXITING)) - return thread; - } + thread = find_alive_thread(reaper); + if (thread) + return thread; } } |