signal: add block_sigmask() for adding sigmask to current->blocked

Abstract the code sequence for adding a signal handler's sa_mask to
current->blocked because the sequence is identical for all architectures.
Furthermore, in the past some architectures actually got this code wrong,
so introduce a wrapper that all architectures can use.

Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Matt Fleming 2012-01-10 15:11:17 -08:00 committed by Linus Torvalds
parent f350b1778f
commit 5e6292c0f2
3 changed files with 23 additions and 5 deletions

View file

@ -682,7 +682,6 @@ static int
handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
struct pt_regs *regs)
{
sigset_t blocked;
int ret;
/* Are we from a system call? */
@ -733,10 +732,7 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
*/
regs->flags &= ~X86_EFLAGS_TF;
sigorsets(&blocked, &current->blocked, &ka->sa.sa_mask);
if (!(ka->sa.sa_flags & SA_NODEFER))
sigaddset(&blocked, sig);
set_current_blocked(&blocked);
block_sigmask(ka, sig);
tracehook_signal_handler(sig, info, ka, regs,
test_thread_flag(TIF_SINGLESTEP));

View file

@ -254,6 +254,7 @@ extern void set_current_blocked(const sigset_t *);
extern int show_unhandled_signals;
extern int get_signal_to_deliver(siginfo_t *info, struct k_sigaction *return_ka, struct pt_regs *regs, void *cookie);
extern void block_sigmask(struct k_sigaction *ka, int signr);
extern void exit_signals(struct task_struct *tsk);
extern struct kmem_cache *sighand_cachep;

View file

@ -2318,6 +2318,27 @@ int get_signal_to_deliver(siginfo_t *info, struct k_sigaction *return_ka,
return signr;
}
/**
* block_sigmask - add @ka's signal mask to current->blocked
* @ka: action for @signr
* @signr: signal that has been successfully delivered
*
* This function should be called when a signal has succesfully been
* delivered. It adds the mask of signals for @ka to current->blocked
* so that they are blocked during the execution of the signal
* handler. In addition, @signr will be blocked unless %SA_NODEFER is
* set in @ka->sa.sa_flags.
*/
void block_sigmask(struct k_sigaction *ka, int signr)
{
sigset_t blocked;
sigorsets(&blocked, &current->blocked, &ka->sa.sa_mask);
if (!(ka->sa.sa_flags & SA_NODEFER))
sigaddset(&blocked, signr);
set_current_blocked(&blocked);
}
/*
* It could be that complete_signal() picked us to notify about the
* group-wide signal. Other threads should be notified now to take