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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 05583C433EF for ; Tue, 14 Dec 2021 22:06:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238334AbhLNWGA (ORCPT ); Tue, 14 Dec 2021 17:06:00 -0500 Received: from sin.source.kernel.org ([145.40.73.55]:58754 "EHLO sin.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237927AbhLNWEr (ORCPT ); Tue, 14 Dec 2021 17:04:47 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sin.source.kernel.org (Postfix) with ESMTPS id C6CB3CE1AFB for ; Tue, 14 Dec 2021 22:04:45 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0F9DFC34625; Tue, 14 Dec 2021 22:04:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1639519482; bh=bHQuoPR51a0Ft1BCAEW/J697y7UT5QEVCJMT/27U+XY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HhmOnGy0UAOieFt7R7UPjJB/azacf3m53KaapXMx2Vta5fa3kGqL7Ef/9Pi2UOfJq 7gBjvPB7Usw7hC0Tg7o7bd16B3EjvbCA99F5r19FUBm90xlwrA4qNSTfUJu54xfV/a S8BOKKw7/Nk2Ietk5fKRWYpWdToaSJOwzNvTfxsN59xp9NsQEuuHbJPd80q0vlB+KS jbCupuzz/bYHDc9Jig/IUnBKTygLBXodC6ESaaXKprnyvxIyO52Bfk8VuPErxOH8xa eNRRv8WIKORoM+oI8JbH/77D/BaPi8+iOZ+/Pe6ea1bO0oOX1eC7Zt1LdoCnYuUxc2 x798m+lq8DSdg== Received: by paulmck-ThinkPad-P17-Gen-1.home (Postfix, from userid 1000) id 76D005C193A; Tue, 14 Dec 2021 14:04:41 -0800 (PST) From: "Paul E. McKenney" To: linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, kernel-team@fb.com, mingo@kernel.org Cc: elver@google.com, andreyknvl@google.com, glider@google.com, dvyukov@google.com, cai@lca.pw, boqun.feng@gmail.com, "Paul E . McKenney" Subject: [PATCH kcsan 15/29] locking/barriers, kcsan: Support generic instrumentation Date: Tue, 14 Dec 2021 14:04:25 -0800 Message-Id: <20211214220439.2236564-15-paulmck@kernel.org> X-Mailer: git-send-email 2.31.1.189.g2e36527f23 In-Reply-To: <20211214220356.GA2236323@paulmck-ThinkPad-P17-Gen-1> References: <20211214220356.GA2236323@paulmck-ThinkPad-P17-Gen-1> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Marco Elver Thus far only smp_*() barriers had been defined by asm-generic/barrier.h based on __smp_*() barriers, because the !SMP case is usually generic. With the introduction of instrumentation, it also makes sense to have asm-generic/barrier.h assist in the definition of instrumented versions of mb(), rmb(), wmb(), dma_rmb(), and dma_wmb(). Because there is no requirement to distinguish the !SMP case, the definition can be simpler: we can avoid also providing fallbacks for the __ prefixed cases, and only check if `defined(__)`, to finally define the KCSAN-instrumented versions. This also allows for the compiler to complain if an architecture accidentally defines both the normal and __ prefixed variant. Signed-off-by: Marco Elver Signed-off-by: Paul E. McKenney --- include/asm-generic/barrier.h | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/include/asm-generic/barrier.h b/include/asm-generic/barrier.h index 27a9c9edfef66..02c4339c8eebf 100644 --- a/include/asm-generic/barrier.h +++ b/include/asm-generic/barrier.h @@ -21,6 +21,31 @@ #define nop() asm volatile ("nop") #endif +/* + * Architectures that want generic instrumentation can define __ prefixed + * variants of all barriers. + */ + +#ifdef __mb +#define mb() do { kcsan_mb(); __mb(); } while (0) +#endif + +#ifdef __rmb +#define rmb() do { kcsan_rmb(); __rmb(); } while (0) +#endif + +#ifdef __wmb +#define wmb() do { kcsan_wmb(); __wmb(); } while (0) +#endif + +#ifdef __dma_rmb +#define dma_rmb() do { kcsan_rmb(); __dma_rmb(); } while (0) +#endif + +#ifdef __dma_wmb +#define dma_wmb() do { kcsan_wmb(); __dma_wmb(); } while (0) +#endif + /* * Force strict CPU ordering. And yes, this is required on UP too when we're * talking to devices. -- 2.31.1.189.g2e36527f23