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 4ABBEC61D97 for ; Fri, 24 Nov 2023 16:32:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231263AbjKXQcl (ORCPT ); Fri, 24 Nov 2023 11:32:41 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40080 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230155AbjKXQch (ORCPT ); Fri, 24 Nov 2023 11:32:37 -0500 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C22001BE for ; Fri, 24 Nov 2023 08:32:42 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=lRSiH2QNyct0O1zK7Llfv4fzLag68+OyvxcKpYofq0w=; b=BbYbQT1LLbBcLhrp53tdnZgluP zbNLnSXvIclXvHBaG5ExEIV/u4nbkydq0lE70BMjBjlIDn/zqhZB3x5G9ODHyt8jcWdSj2KrI0Czz sFkKeyYQpmoF7ryksGfmWLRKC5hr2Dd/ZInEp9zriaiHBgfu+fsFLKFkyDBSopKQKMblsIFzCGe6n Hd+zeZ5iAYYwB3bIfFQzrlx+I/0D356XXIgzftK2W8zprTjrq0xGD5iR91DGCjhvnv57HMUc39oGY ciAFdsX7LVJLtN+fN0zE2VtlHyhLng8tWWsdl4mD9AxIWuc1MrUWsRVJnkzq5NGfxF4YRNPZfwbjl TIoYX5lw==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.96 #2 (Red Hat Linux)) id 1r6Z6L-00Dwsr-2g; Fri, 24 Nov 2023 16:32:23 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 854253002BE; Fri, 24 Nov 2023 17:32:20 +0100 (CET) Date: Fri, 24 Nov 2023 17:32:20 +0100 From: Peter Zijlstra To: guoren@kernel.org Cc: mark.rutland@arm.com, keescook@chromium.org, paulmck@kernel.org, ubizjak@gmail.com, tglx@linutronix.de, linux-kernel@vger.kernel.org, Guo Ren Subject: Re: [PATCH] locking/atomic: Add acquire and release fence for atomic(64)_read(set) Message-ID: <20231124163220.GU3818@noisy.programming.kicks-ass.net> References: <20231124162508.3331357-1-guoren@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20231124162508.3331357-1-guoren@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 24, 2023 at 11:25:08AM -0500, guoren@kernel.org wrote: > From: Guo Ren > > The definitions of atomic(64)_read(set) are relax version, so > add acquire and release fence for them. > > Signed-off-by: Guo Ren > Signed-off-by: Guo Ren > --- You lost the script change? > include/linux/atomic/atomic-arch-fallback.h | 14 +++++++++++--- > 1 file changed, 11 insertions(+), 3 deletions(-) > > diff --git a/include/linux/atomic/atomic-arch-fallback.h b/include/linux/atomic/atomic-arch-fallback.h > index 18f5744dfb5d..9775900eeefd 100644 > --- a/include/linux/atomic/atomic-arch-fallback.h > +++ b/include/linux/atomic/atomic-arch-fallback.h > @@ -460,7 +460,10 @@ raw_atomic_read_acquire(const atomic_t *v) > #if defined(arch_atomic_read_acquire) > return arch_atomic_read_acquire(v); > #elif defined(arch_atomic_read) > - return arch_atomic_read(v); > + int ret; > + ret = arch_atomic_read(v); > + __atomic_acquire_fence(); > + return ret; > #else > int ret; > > @@ -509,6 +512,7 @@ raw_atomic_set_release(atomic_t *v, int i) > #if defined(arch_atomic_set_release) > arch_atomic_set_release(v, i); > #elif defined(arch_atomic_set) > + __atomic_release_fence(); > arch_atomic_set(v, i); > #else > if (__native_word(atomic_t)) { > @@ -2576,7 +2580,10 @@ raw_atomic64_read_acquire(const atomic64_t *v) > #if defined(arch_atomic64_read_acquire) > return arch_atomic64_read_acquire(v); > #elif defined(arch_atomic64_read) > - return arch_atomic64_read(v); > + s64 ret; > + ret = arch_atomic64_read(v); > + __atomic_acquire_fence(); > + return ret; > #else > s64 ret; > > @@ -2625,6 +2632,7 @@ raw_atomic64_set_release(atomic64_t *v, s64 i) > #if defined(arch_atomic64_set_release) > arch_atomic64_set_release(v, i); > #elif defined(arch_atomic64_set) > + __atomic_release_fence(); > arch_atomic64_set(v, i); > #else > if (__native_word(atomic64_t)) { > @@ -4657,4 +4665,4 @@ raw_atomic64_dec_if_positive(atomic64_t *v) > } > > #endif /* _LINUX_ATOMIC_FALLBACK_H */ > -// 202b45c7db600ce36198eb1f1fc2c2d5268ace2d > +// 3135f55051cf62b76664e528bf04337c44a14e72 > -- > 2.36.1 >