Eric W. Biederman <mailto:ebied...@xmission.com> writes:
> liuchao <liuchao...@huawei.com> writes: > > > I want to dermine which thread is the last one to enter do_exit in > > profile_task_exit. But when a lot of threads exit, tsk->signal->live > > is not correct since it decrease after profile_task_exit. > > I don't think that would be wise. > > Any additional code before the sanity checks at the start of do_exit seems > like a bad idea. > > We could probably move the decrement of tsk->signal->live a little earlier, > but not that much earlier in the function. > > Does profile_task_exit even make sense that early in the code? If the code > is doing much of anything that is a completely inappopriate placement of > profile_task_exit. I think so too. Move the decrement of tsk->signal->live after the sanity checks, then profile_task_exit and kcov_task_exit make more sense. > > Eric > > > > Signed-off-by: liuchao <liuchao...@huawei.com> > > --- > > kernel/exit.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/kernel/exit.c b/kernel/exit.c index > > ce2a75bc0ade..1693764bc356 100644 > > --- a/kernel/exit.c > > +++ b/kernel/exit.c > > @@ -708,6 +708,7 @@ void __noreturn do_exit(long code) > > struct task_struct *tsk = current; > > int group_dead; > > > > + group_dead = atomic_dec_and_test(&tsk->signal->live); > > profile_task_exit(tsk); > > kcov_task_exit(tsk); > > > > @@ -755,7 +756,6 @@ void __noreturn do_exit(long code) > > if (tsk->mm) > > sync_mm_rss(tsk->mm); > > acct_update_integrals(tsk); > > - group_dead = atomic_dec_and_test(&tsk->signal->live); > > if (group_dead) { > > /* > > * If the last thread of global init has exited, panic