From be0e6f290f78b84a3b21b8c8c46819c4514fe632 Mon Sep 17 00:00:00 2001 From: Oleg Nesterov Date: Fri, 6 Nov 2015 16:32:22 -0800 Subject: [PATCH] signal: turn dequeue_signal_lock() into kernel_dequeue_signal() 1. Rename dequeue_signal_lock() to kernel_dequeue_signal(). This matches another "for kthreads only" kernel_sigaction() helper. 2. Remove the "tsk" and "mask" arguments, they are always current and current->blocked. And it is simply wrong if tsk != current. 3. We could also remove the 3rd "siginfo_t *info" arg but it looks potentially useful. However we can simplify the callers if we change kernel_dequeue_signal() to accept info => NULL. 4. Remove _irqsave, it is never called from atomic context. Signed-off-by: Oleg Nesterov Reviewed-by: Tejun Heo Cc: David Woodhouse Cc: Felipe Balbi Cc: Markus Pargmann Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/block/nbd.c | 15 ++++----------- drivers/usb/gadget/function/f_mass_storage.c | 4 +--- fs/jffs2/background.c | 3 +-- include/linux/sched.h | 11 ++++++----- 4 files changed, 12 insertions(+), 21 deletions(-) diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index 1b87623381e2..93b3f99b6865 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -444,9 +444,7 @@ static int nbd_thread_recv(struct nbd_device *nbd) spin_unlock_irqrestore(&nbd->tasks_lock, flags); if (signal_pending(current)) { - siginfo_t info; - - ret = dequeue_signal_lock(current, ¤t->blocked, &info); + ret = kernel_dequeue_signal(NULL); dev_warn(nbd_to_dev(nbd), "pid %d, %s, got signal %d\n", task_pid_nr(current), current->comm, ret); mutex_lock(&nbd->tx_lock); @@ -560,11 +558,8 @@ static int nbd_thread_send(void *data) !list_empty(&nbd->waiting_queue)); if (signal_pending(current)) { - siginfo_t info; - int ret; + int ret = kernel_dequeue_signal(NULL); - ret = dequeue_signal_lock(current, ¤t->blocked, - &info); dev_warn(nbd_to_dev(nbd), "pid %d, %s, got signal %d\n", task_pid_nr(current), current->comm, ret); mutex_lock(&nbd->tx_lock); @@ -592,10 +587,8 @@ static int nbd_thread_send(void *data) spin_unlock_irqrestore(&nbd->tasks_lock, flags); /* Clear maybe pending signals */ - if (signal_pending(current)) { - siginfo_t info; - dequeue_signal_lock(current, ¤t->blocked, &info); - } + if (signal_pending(current)) + kernel_dequeue_signal(NULL); return 0; } diff --git a/drivers/usb/gadget/function/f_mass_storage.c b/drivers/usb/gadget/function/f_mass_storage.c index cd54e72a6c50..5ec533826621 100644 --- a/drivers/usb/gadget/function/f_mass_storage.c +++ b/drivers/usb/gadget/function/f_mass_storage.c @@ -2345,7 +2345,6 @@ static void fsg_disable(struct usb_function *f) static void handle_exception(struct fsg_common *common) { - siginfo_t info; int i; struct fsg_buffhd *bh; enum fsg_state old_state; @@ -2357,8 +2356,7 @@ static void handle_exception(struct fsg_common *common) * into a high-priority EXIT exception. */ for (;;) { - int sig = - dequeue_signal_lock(current, ¤t->blocked, &info); + int sig = kernel_dequeue_signal(NULL); if (!sig) break; if (sig != SIGUSR1) { diff --git a/fs/jffs2/background.c b/fs/jffs2/background.c index bb9cebc9ca8a..f3145fd86d86 100644 --- a/fs/jffs2/background.c +++ b/fs/jffs2/background.c @@ -121,13 +121,12 @@ static int jffs2_garbage_collect_thread(void *_c) /* Put_super will send a SIGKILL and then wait on the sem. */ while (signal_pending(current) || freezing(current)) { - siginfo_t info; unsigned long signr; if (try_to_freeze()) goto again; - signr = dequeue_signal_lock(current, ¤t->blocked, &info); + signr = kernel_dequeue_signal(NULL); switch(signr) { case SIGSTOP: diff --git a/include/linux/sched.h b/include/linux/sched.h index 923ec1a9b2b4..3d54924b4b86 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -2462,14 +2462,15 @@ extern void ignore_signals(struct task_struct *); extern void flush_signal_handlers(struct task_struct *, int force_default); extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info); -static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info) +static inline int kernel_dequeue_signal(siginfo_t *info) { - unsigned long flags; + struct task_struct *tsk = current; + siginfo_t __info; int ret; - spin_lock_irqsave(&tsk->sighand->siglock, flags); - ret = dequeue_signal(tsk, mask, info); - spin_unlock_irqrestore(&tsk->sighand->siglock, flags); + spin_lock_irq(&tsk->sighand->siglock); + ret = dequeue_signal(tsk, &tsk->blocked, info ?: &__info); + spin_unlock_irq(&tsk->sighand->siglock); return ret; } -- GitLab