The patch titled Subject: exit: reparent: introduce find_child_reaper() has been removed from the -mm tree. Its filename was exit-reparent-introduce-find_child_reaper.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ From: Oleg Nesterov <oleg@xxxxxxxxxx> Subject: exit: reparent: introduce find_child_reaper() find_new_reaper() does 2 completely different things. Not only it finds a reaper, it also updates pid_ns->child_reaper or kills the whole namespace if the caller is ->child_reaper. Now that has_child_subreaper logic doesn't depend on child_reaper check we can move that pid_ns code into a separate helper. IMHO this makes the code more clean, and this allows the next changes. Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx> Cc: Aaron Tomlin <atomlin@xxxxxxxxxx> Cc: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx> Cc: Kay Sievers <kay@xxxxxxxx> Cc: Lennart Poettering <lennart@xxxxxxxxxxxxxx> Cc: Sterling Alexander <stalexan@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- kernel/exit.c | 56 ++++++++++++++++++++++++++++++------------------ 1 file changed, 35 insertions(+), 21 deletions(-) diff -puN kernel/exit.c~exit-reparent-introduce-find_child_reaper kernel/exit.c --- a/kernel/exit.c~exit-reparent-introduce-find_child_reaper +++ a/kernel/exit.c @@ -459,6 +459,34 @@ static void exit_mm(struct task_struct * clear_thread_flag(TIF_MEMDIE); } +static struct task_struct *find_child_reaper(struct task_struct *father) + __releases(&tasklist_lock) + __acquires(&tasklist_lock) +{ + struct pid_namespace *pid_ns = task_active_pid_ns(father); + struct task_struct *reaper = pid_ns->child_reaper; + + if (likely(reaper != father)) + return reaper; + + for_each_thread(father, reaper) { + if (reaper->flags & PF_EXITING) + continue; + pid_ns->child_reaper = reaper; + return reaper; + } + + write_unlock_irq(&tasklist_lock); + if (unlikely(pid_ns == &init_pid_ns)) { + panic("Attempted to kill init! exitcode=0x%08x\n", + father->signal->group_exit_code ?: father->exit_code); + } + zap_pid_ns_processes(pid_ns); + write_lock_irq(&tasklist_lock); + + return father; +} + /* * When we die, we re-parent all our children, and try to: * 1. give them to another thread in our thread group, if such a member exists @@ -466,33 +494,17 @@ static void exit_mm(struct task_struct * * child_subreaper for its children (like a service manager) * 3. give it to the init process (PID 1) in our pid namespace */ -static struct task_struct *find_new_reaper(struct task_struct *father) - __releases(&tasklist_lock) - __acquires(&tasklist_lock) +static struct task_struct *find_new_reaper(struct task_struct *father, + struct task_struct *child_reaper) { - struct pid_namespace *pid_ns = task_active_pid_ns(father); struct task_struct *thread; for_each_thread(father, thread) { if (thread->flags & PF_EXITING) continue; - if (unlikely(pid_ns->child_reaper == father)) - pid_ns->child_reaper = thread; return thread; } - if (unlikely(pid_ns->child_reaper == father)) { - write_unlock_irq(&tasklist_lock); - if (unlikely(pid_ns == &init_pid_ns)) { - panic("Attempted to kill init! exitcode=0x%08x\n", - father->signal->group_exit_code ?: - father->exit_code); - } - - zap_pid_ns_processes(pid_ns); - write_lock_irq(&tasklist_lock); - } - if (father->signal->has_child_subreaper) { struct task_struct *reaper; /* @@ -501,7 +513,7 @@ static struct task_struct *find_new_reap * namespace, this is safe because all its threads are dead. */ for (reaper = father; - !same_thread_group(reaper, pid_ns->child_reaper); + !same_thread_group(reaper, child_reaper); reaper = reaper->real_parent) { /* call_usermodehelper() descendants need this check */ if (reaper == &init_task) @@ -515,7 +527,7 @@ static struct task_struct *find_new_reap } } - return pid_ns->child_reaper; + return child_reaper; } /* @@ -552,7 +564,9 @@ static void forget_original_parent(struc exit_ptrace(father, &dead_children); /* Can drop and reacquire tasklist_lock */ - reaper = find_new_reaper(father); + reaper = find_child_reaper(father); + + reaper = find_new_reaper(father, reaper); list_for_each_entry(p, &father->children, sibling) { for_each_thread(p, t) { t->real_parent = reaper; _ Patches currently in -mm which might be from oleg@xxxxxxxxxx are origin.patch mmfs-introduce-helpers-around-the-i_mmap_mutex.patch mm-use-new-helper-functions-around-the-i_mmap_mutex.patch mm-convert-i_mmap_mutex-to-rwsem.patch mm-rmap-share-the-i_mmap_rwsem.patch uprobes-share-the-i_mmap_rwsem.patch mm-xip-share-the-i_mmap_rwsem.patch mm-memory-failure-share-the-i_mmap_rwsem.patch mm-nommu-share-the-i_mmap_rwsem.patch mm-memoryc-share-the-i_mmap_rwsem.patch remove-unnecessary-is_valid_nodemask.patch oom-dont-assume-that-a-coredumping-thread-will-exit-soon.patch oom-dont-assume-that-a-coredumping-thread-will-exit-soon-v2.patch oom-dont-assume-that-a-coredumping-thread-will-exit-soon-v2-fix.patch oom-kill-the-insufficient-and-no-longer-needed-pt_trace_exit-check.patch linux-next.patch all-arches-signal-move-restart_block-to-struct-task_struct.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html