From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756546AbcIFOBD (ORCPT ); Tue, 6 Sep 2016 10:01:03 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37428 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756540AbcIFOA6 (ORCPT ); Tue, 6 Sep 2016 10:00:58 -0400 Date: Tue, 6 Sep 2016 16:00:55 +0200 From: Oleg Nesterov To: Ingo Molnar , Peter Zijlstra Cc: Al Viro , Bart Van Assche , Johannes Weiner , Linus Torvalds , Neil Brown , linux-kernel@vger.kernel.org Subject: [PATCH V2 4/4] sched/wait: introduce init_wait_entry() Message-ID: <20160906140055.GA6167@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160906140013.GA6139@redhat.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Tue, 06 Sep 2016 14:00:58 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The partial initialization of wait_queue_t in prepare_to_wait_event() looks ugly. This was done to shrink .text, but we can simply add the new helper which does the full initialization and shrink the compiled code a bit more. And. This way prepare_to_wait_event() can have more users. In particular we are ready to remove the signal_pending_state() checks from wait_bit_action_f helpers and change __wait_on_bit_lock() to use prepare_to_wait_event(). Signed-off-by: Oleg Nesterov --- include/linux/wait.h | 9 +++------ kernel/sched/wait.c | 12 +++++++++--- 2 files changed, 12 insertions(+), 9 deletions(-) diff --git a/include/linux/wait.h b/include/linux/wait.h index 52953a5..1b8a930 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -248,6 +248,8 @@ wait_queue_head_t *bit_waitqueue(void *, int); (!__builtin_constant_p(state) || \ state == TASK_INTERRUPTIBLE || state == TASK_KILLABLE) \ +extern void init_wait_entry(wait_queue_t *__wait, int flags); + /* * The below macro ___wait_event() has an explicit shadow of the __ret * variable when used from the wait_event_*() macros. @@ -266,12 +268,7 @@ wait_queue_head_t *bit_waitqueue(void *, int); wait_queue_t __wait; \ long __ret = ret; /* explicit shadow */ \ \ - INIT_LIST_HEAD(&__wait.task_list); \ - if (exclusive) \ - __wait.flags = WQ_FLAG_EXCLUSIVE; \ - else \ - __wait.flags = 0; \ - \ + init_wait_entry(&__wait, exclusive ? WQ_FLAG_EXCLUSIVE : 0); \ for (;;) { \ long __int = prepare_to_wait_event(&wq, &__wait, state);\ \ diff --git a/kernel/sched/wait.c b/kernel/sched/wait.c index 47c4d62..61dcee1 100644 --- a/kernel/sched/wait.c +++ b/kernel/sched/wait.c @@ -196,14 +196,20 @@ prepare_to_wait_exclusive(wait_queue_head_t *q, wait_queue_t *wait, int state) } EXPORT_SYMBOL(prepare_to_wait_exclusive); +void init_wait_entry(wait_queue_t *wait, int flags) +{ + wait->flags = flags; + wait->private = current; + wait->func = autoremove_wake_function; + INIT_LIST_HEAD(&wait->task_list); +} +EXPORT_SYMBOL(init_wait_entry); + long prepare_to_wait_event(wait_queue_head_t *q, wait_queue_t *wait, int state) { unsigned long flags; long ret = 0; - wait->private = current; - wait->func = autoremove_wake_function; - spin_lock_irqsave(&q->lock, flags); if (unlikely(signal_pending_state(state, current))) { /* -- 2.5.0