From 88531f725bd52e37a7be726860e4ff3f09031d89 Mon Sep 17 00:00:00 2001 From: Oleg Nesterov Date: Tue, 28 Mar 2006 16:11:24 -0800 Subject: [PATCH] [PATCH] do_sigaction: don't take tasklist_lock do_sigaction() does not need tasklist_lock anymore, we can simplify the code. Signed-off-by: Oleg Nesterov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/signal.c | 22 +++------------------- 1 file changed, 3 insertions(+), 19 deletions(-) diff --git a/kernel/signal.c b/kernel/signal.c index e3bdec91462..2dfaa5076c3 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -2301,8 +2301,7 @@ sys_rt_sigqueueinfo(int pid, int sig, siginfo_t __user *uinfo) return kill_proc_info(sig, &info, pid); } -int -do_sigaction(int sig, struct k_sigaction *act, struct k_sigaction *oact) +int do_sigaction(int sig, struct k_sigaction *act, struct k_sigaction *oact) { struct k_sigaction *k; sigset_t mask; @@ -2328,6 +2327,7 @@ do_sigaction(int sig, struct k_sigaction *act, struct k_sigaction *oact) if (act) { sigdelsetmask(&act->sa.sa_mask, sigmask(SIGKILL) | sigmask(SIGSTOP)); + *k = *act; /* * POSIX 3.3.1.3: * "Setting a signal action to SIG_IGN for a signal that is @@ -2340,19 +2340,8 @@ do_sigaction(int sig, struct k_sigaction *act, struct k_sigaction *oact) * be discarded, whether or not it is blocked" */ if (act->sa.sa_handler == SIG_IGN || - (act->sa.sa_handler == SIG_DFL && - sig_kernel_ignore(sig))) { - /* - * This is a fairly rare case, so we only take the - * tasklist_lock once we're sure we'll need it. - * Now we must do this little unlock and relock - * dance to maintain the lock hierarchy. - */ + (act->sa.sa_handler == SIG_DFL && sig_kernel_ignore(sig))) { struct task_struct *t = current; - spin_unlock_irq(&t->sighand->siglock); - read_lock(&tasklist_lock); - spin_lock_irq(&t->sighand->siglock); - *k = *act; sigemptyset(&mask); sigaddset(&mask, sig); rm_from_queue_full(&mask, &t->signal->shared_pending); @@ -2361,12 +2350,7 @@ do_sigaction(int sig, struct k_sigaction *act, struct k_sigaction *oact) recalc_sigpending_tsk(t); t = next_thread(t); } while (t != current); - spin_unlock_irq(¤t->sighand->siglock); - read_unlock(&tasklist_lock); - return 0; } - - *k = *act; } spin_unlock_irq(¤t->sighand->siglock); -- 2.20.1