The patch titled
introduce TASK_DEAD state
has been added to the -mm tree. Its filename is
introduce-task_dead-state.patch
See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this
------------------------------------------------------
Subject: introduce TASK_DEAD state
From: Oleg Nesterov <oleg@xxxxxxxxxx>
I am not sure about this patch, I am asking Ingo to take a decision.
task_struct->state == EXIT_DEAD is a very special case, to avoid a confusion
it makes sense to introduce a new state, TASK_DEAD, while EXIT_DEAD should
live only in ->exit_state as documented in sched.h.
Note that this state is not visible to user-space, get_task_state() masks off
unsuitable states.
Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxx>
---
include/linux/sched.h | 1 +
kernel/exit.c | 2 +-
kernel/sched.c | 8 ++++----
mm/oom_kill.c | 2 +-
4 files changed, 7 insertions(+), 6 deletions(-)
diff -puN include/linux/sched.h~introduce-task_dead-state include/linux/sched.h
--- a/include/linux/sched.h~introduce-task_dead-state
+++ a/include/linux/sched.h
@@ -148,6 +148,7 @@ extern unsigned long weighted_cpuload(co
#define EXIT_DEAD 32
/* in tsk->state again */
#define TASK_NONINTERACTIVE 64
+#define TASK_DEAD 128
#define __set_task_state(tsk, state_value) \
do { (tsk)->state = (state_value); } while (0)
diff -puN kernel/exit.c~introduce-task_dead-state kernel/exit.c
--- a/kernel/exit.c~introduce-task_dead-state
+++ a/kernel/exit.c
@@ -956,7 +956,7 @@ fastcall NORET_TYPE void do_exit(long co
preempt_disable();
/* causes final put_task_struct in finish_task_switch(). */
- tsk->state = EXIT_DEAD;
+ tsk->state = TASK_DEAD;
schedule();
BUG();
diff -puN kernel/sched.c~introduce-task_dead-state kernel/sched.c
--- a/kernel/sched.c~introduce-task_dead-state
+++ a/kernel/sched.c
@@ -1751,10 +1751,10 @@ static inline void finish_task_switch(st
/*
* A task struct has one reference for the use as "current".
- * If a task dies, then it sets EXIT_DEAD in tsk->state and calls
+ * If a task dies, then it sets TASK_DEAD in tsk->state and calls
* schedule one last time. The schedule call will never return, and
* the scheduled task must drop that reference.
- * The test for EXIT_DEAD must occur while the runqueue locks are
+ * The test for TASK_DEAD must occur while the runqueue locks are
* still held, otherwise prev could be scheduled on another cpu, die
* there before we look at prev->state, and then the reference would
* be dropped twice.
@@ -1765,7 +1765,7 @@ static inline void finish_task_switch(st
finish_lock_switch(rq, prev);
if (mm)
mmdrop(mm);
- if (unlikely(prev_state == EXIT_DEAD)) {
+ if (unlikely(prev_state == TASK_DEAD)) {
/*
* Remove function-return probe instances associated with this
* task and put them back on the free list.
@@ -5116,7 +5116,7 @@ static void migrate_dead(unsigned int de
BUG_ON(p->exit_state != EXIT_ZOMBIE && p->exit_state != EXIT_DEAD);
/* Cannot have done final schedule yet: would have vanished. */
- BUG_ON(p->state == EXIT_DEAD);
+ BUG_ON(p->state == TASK_DEAD);
get_task_struct(p);
diff -puN mm/oom_kill.c~introduce-task_dead-state mm/oom_kill.c
--- a/mm/oom_kill.c~introduce-task_dead-state
+++ a/mm/oom_kill.c
@@ -228,7 +228,7 @@ static struct task_struct *select_bad_pr
p->flags & PF_EXITING;
if (releasing) {
/* TASK_DEAD tasks have already released their mm */
- if (p->state == EXIT_DEAD)
+ if (p->state == TASK_DEAD)
continue;
if (p->flags & PF_EXITING && p == current) {
chosen = p;
_
Patches currently in -mm which might be from oleg@xxxxxxxxxx are
origin.patch
for-2618-revert-drop-tasklist-lock-in-do_sched_setscheduler.patch
futex_find_get_task-remove-an-obscure-exit_zombie-check.patch
pid-implement-transfer_pid-and-use-it-to-simplify-de_thread.patch
pid-remove-temporary-debug-code-in-attach_pid.patch
rtmutex-clean-up-and-remove-some-extra-spinlocks.patch
rtmutex-clean-up-and-remove-some-extra-spinlocks-more.patch
elf_core_dump-dont-take-tasklist_lock.patch
elf_fdpic_core_dump-dont-take-tasklist_lock.patch
has_stopped_jobs-cleanup.patch
__dequeue_signal-cleanup.patch
do_sched_setscheduler-dont-take-tasklist_lock.patch
introduce-is_rt_policy-helper.patch
sched_setscheduler-fix-policy-checks.patch
reparent_to_init-use-has_rt_policy.patch
copy_process-cosmetic-ioprio-tweak.patch
futex_find_get_task-dont-take-tasklist_lock.patch
sys_get_robust_list-dont-take-tasklist_lock.patch
set-exit_dead-state-in-do_exit-not-in-schedule.patch
kill-pf_dead-flag.patch
introduce-task_dead-state.patch
simplify-pid-iterators.patch
pidhash-temporary-debug-checks.patch
-
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