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[2620:137:e000::1:20]) by mx.google.com with ESMTP id 73-20020a63004c000000b00542c0357ee7si6419896pga.57.2023.06.06.07.47.50; Tue, 06 Jun 2023 07:48:02 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@linutronix.de header.s=2020 header.b=3vJpsNCd; dkim=neutral (no key) header.i=@linutronix.de; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=linutronix.de Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238248AbjFFOim (ORCPT + 99 others); Tue, 6 Jun 2023 10:38:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41404 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238096AbjFFOiS (ORCPT ); Tue, 6 Jun 2023 10:38:18 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B284F19AD for ; Tue, 6 Jun 2023 07:37:50 -0700 (PDT) Message-ID: <20230606142032.095893220@linutronix.de> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1686062269; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: references:references; bh=NkUrDTbG2kUXm4FwAX4frsR2bQohb+OmRpFyHE6t2mA=; b=3vJpsNCd5Cty9AxlHVIAAC4r6I8hNXiaYpKzMmQUemVg9DoLwOy5WiGazhw+1WqznMIonr cgmpaFC/pWVkbwMhxfiKohvbxtNUHKzO8h9Ykar5+D3cVgyPtCtkrq2xfVG5WrnGwVnrXg z4aULVl0zsL31Js+l0Rx+1lquD6nsZ7aSazjFG+8bHwI/WXTAs+6P89jKbOiNyvxhkGRYU 2gE4nWX0rTtcvxsbJQryz6Tkmw2zobEwcocwp17CV8kVkhJjZ0HF2gj6FP1kVArZhWIilO N8HJjFNqli/nezp9omLTO59XWsqIRqeMfIIheNVfJFz846u2MYZZ4azVZ0FxEg== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1686062269; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: references:references; bh=NkUrDTbG2kUXm4FwAX4frsR2bQohb+OmRpFyHE6t2mA=; b=FOhRJm+RNuhNW+Fzm6R39QCjgVamcm3e4KM3EJudB2HxdLzadgjA+Nkpt2PHOYjQ6frDo5 U1fiiTT0AP6Pu+Cw== From: Thomas Gleixner To: LKML Cc: Frederic Weisbecker , Anna-Maria Behnsen , John Stultz , Peter Zijlstra , Ingo Molnar , Stephen Boyd , Eric Biederman , Oleg Nesterov Subject: [patch 19/45] signal: Remove task argument from dequeue_signal() References: <20230606132949.068951363@linutronix.de> MIME-Version: 1.0 Date: Tue, 6 Jun 2023 16:37:48 +0200 (CEST) X-Spam-Status: No, score=-4.4 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_MED,SPF_HELO_NONE, SPF_PASS,T_SCC_BODY_TEXT_LINE,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1767965072961608840?= X-GMAIL-MSGID: =?utf-8?q?1767965072961608840?= The task pointer which is handed to dequeue_signal() is always current. The argument along with the first comment about signalfd in that function is confusing at best. Remove it and use current internally. Update the stale comment for dequeue_signal() while at it. Signed-off-by: Thomas Gleixner Reviewed-by: Frederic Weisbecker --- fs/signalfd.c | 4 ++-- include/linux/sched/signal.h | 5 ++--- kernel/signal.c | 23 ++++++++++------------- 3 files changed, 14 insertions(+), 18 deletions(-) --- a/fs/signalfd.c +++ b/fs/signalfd.c @@ -160,7 +160,7 @@ static ssize_t signalfd_dequeue(struct s DECLARE_WAITQUEUE(wait, current); spin_lock_irq(¤t->sighand->siglock); - ret = dequeue_signal(current, &ctx->sigmask, info, &type); + ret = dequeue_signal(&ctx->sigmask, info, &type); switch (ret) { case 0: if (!nonblock) @@ -175,7 +175,7 @@ static ssize_t signalfd_dequeue(struct s add_wait_queue(¤t->sighand->signalfd_wqh, &wait); for (;;) { set_current_state(TASK_INTERRUPTIBLE); - ret = dequeue_signal(current, &ctx->sigmask, info, &type); + ret = dequeue_signal(&ctx->sigmask, info, &type); if (ret != 0) break; if (signal_pending(current)) { --- a/include/linux/sched/signal.h +++ b/include/linux/sched/signal.h @@ -275,8 +275,7 @@ static inline void signal_set_stop_flags extern void flush_signals(struct task_struct *); 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 *task, sigset_t *mask, - kernel_siginfo_t *info, enum pid_type *type); +extern int dequeue_signal(sigset_t *mask, kernel_siginfo_t *info, enum pid_type *type); static inline int kernel_dequeue_signal(void) { @@ -286,7 +285,7 @@ static inline int kernel_dequeue_signal( int ret; spin_lock_irq(&task->sighand->siglock); - ret = dequeue_signal(task, &task->blocked, &__info, &__type); + ret = dequeue_signal(&task->blocked, &__info, &__type); spin_unlock_irq(&task->sighand->siglock); return ret; --- a/kernel/signal.c +++ b/kernel/signal.c @@ -621,20 +621,18 @@ static int __dequeue_signal(struct sigpe } /* - * Dequeue a signal and return the element to the caller, which is - * expected to free it. - * - * All callers have to hold the siglock. + * Try to dequeue a signal. If a deliverable signal is found fill in the + * caller provided siginfo and return the signal number. Otherwise return + * 0. */ -int dequeue_signal(struct task_struct *tsk, sigset_t *mask, - kernel_siginfo_t *info, enum pid_type *type) +int dequeue_signal(sigset_t *mask, kernel_siginfo_t *info, enum pid_type *type) { + struct task_struct *tsk = current; bool resched_timer = false; int signr; - /* We only dequeue private signals from ourselves, we don't let - * signalfd steal them - */ + lockdep_assert_held(&tsk->sighand->siglock); + *type = PIDTYPE_PID; signr = __dequeue_signal(&tsk->pending, mask, info, &resched_timer); if (!signr) { @@ -2751,8 +2749,7 @@ bool get_signal(struct ksignal *ksig) type = PIDTYPE_PID; signr = dequeue_synchronous_signal(&ksig->info); if (!signr) - signr = dequeue_signal(current, ¤t->blocked, - &ksig->info, &type); + signr = dequeue_signal(¤t->blocked, &ksig->info, &type); if (!signr) break; /* will return 0 */ @@ -3606,7 +3603,7 @@ static int do_sigtimedwait(const sigset_ signotset(&mask); spin_lock_irq(&tsk->sighand->siglock); - sig = dequeue_signal(tsk, &mask, info, &type); + sig = dequeue_signal(&mask, info, &type); if (!sig && timeout) { /* * None ready, temporarily unblock those we're interested @@ -3625,7 +3622,7 @@ static int do_sigtimedwait(const sigset_ spin_lock_irq(&tsk->sighand->siglock); __set_task_blocked(tsk, &tsk->real_blocked); sigemptyset(&tsk->real_blocked); - sig = dequeue_signal(tsk, &mask, info, &type); + sig = dequeue_signal(&mask, info, &type); } spin_unlock_irq(&tsk->sighand->siglock);