From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4A3DDC4338F for ; Fri, 30 Jul 2021 14:21:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 21FD160462 for ; Fri, 30 Jul 2021 14:21:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239170AbhG3OV1 (ORCPT ); Fri, 30 Jul 2021 10:21:27 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:55698 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239191AbhG3ORp (ORCPT ); Fri, 30 Jul 2021 10:17:45 -0400 Message-ID: <20210730135206.696939121@linutronix.de> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1627654655; 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: content-transfer-encoding:content-transfer-encoding: references:references; bh=QJmP+ZWrvcKIphqxWJVnNjBXhaJqFhE594/qM5BJ198=; b=EFYrpdnrQIVZZL7XTohvehZA52yD+yek0dx7whzg9Id3c7hIaM5MRG7L7avQ3xQTnzCHKr dIgv8QHMdrBzARWBnV95+yfLMN8DRLhD5MHfxyGJUhdDr6J2yMEMCpI9JHvUDdir2MfzNI In/xVhE8DoFRKcYPfdw1+8c/nqiE+mGhtMi3+fiObsN7xDwFOe/CGCNSywSU6GZv97IPSL X6zOysWX5OUxRyaEKFjA+YMxGCHXx22hWQMqyVjIUJvKTyEej2UHkc1omf/zXiMeYUw3nv 1bsZjIgDKPyQ4QwxLNjhLCasAIb0Z0gkeyYy+sqCzm/UOjnCnK1P77wIp0mjUQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1627654655; 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: content-transfer-encoding:content-transfer-encoding: references:references; bh=QJmP+ZWrvcKIphqxWJVnNjBXhaJqFhE594/qM5BJ198=; b=HeVZ5RPKOqBeLmo0JNtdgoqznR6CBaW+3BSlh9UByjRt+pZsMG+LjHVkuZh0iCvcB4rU5r O++g+xqPfnA8UzAg== Date: Fri, 30 Jul 2021 15:50:34 +0200 From: Thomas Gleixner To: LKML Cc: Peter Zijlstra , Ingo Molnar , Juri Lelli , Steven Rostedt , Daniel Bristot de Oliveira , Will Deacon , Waiman Long , Boqun Feng , Sebastian Andrzej Siewior , Davidlohr Bueso Subject: [patch 27/63] locking/spinlock: Provide RT specific spinlock type References: <20210730135007.155909613@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-transfer-encoding: 8-bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Thomas Gleixner RT replaces spinlocks with a simple wrapper around a rtmutex which turns spinlocks on RT into 'sleeping' spinlocks. The actual implementation of the spinlock API differs from a regular rtmutex as it does neither handle timeouts nor signals and it is state preserving accross the lock operation. Signed-off-by: Thomas Gleixner --- include/linux/spinlock_types.h | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) --- --- a/include/linux/spinlock_types.h +++ b/include/linux/spinlock_types.h @@ -51,6 +51,9 @@ #define DEFINE_RAW_SPINLOCK(x) raw_spinlock_t x = __RAW_SPIN_LOCK_UNLOCKED(x) +#ifndef CONFIG_PREEMPT_RT + +/* Non PREEMPT_RT kernels map spinlock to raw_spinlock */ typedef struct spinlock { union { struct raw_spinlock rlock; @@ -79,6 +82,29 @@ typedef struct spinlock { #define DEFINE_SPINLOCK(x) spinlock_t x = __SPIN_LOCK_UNLOCKED(x) +#else /* !CONFIG_PREEMPT_RT */ + +/* PREEMPT_RT kernels map spinlock to rt_mutex */ +#include + +typedef struct spinlock { + struct rt_mutex_base lock; +#ifdef CONFIG_DEBUG_LOCK_ALLOC + struct lockdep_map dep_map; +#endif +} spinlock_t; + +#define __SPIN_LOCK_UNLOCKED(name) \ + { \ + .lock = __RT_MUTEX_BASE_INITIALIZER(name.lock), \ + SPIN_DEP_MAP_INIT(name) \ + } + +#define DEFINE_SPINLOCK(name) \ + spinlock_t name = __SPIN_LOCK_UNLOCKED(name) + +#endif /* CONFIG_PREEMPT_RT */ + #include #endif /* __LINUX_SPINLOCK_TYPES_H */