From owner-dev-commits-src-branches@freebsd.org Wed Mar 3 07:07:20 2021 Return-Path: Delivered-To: dev-commits-src-branches@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 8733A5600F7; Wed, 3 Mar 2021 07:07:20 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4Dr4nN3RWqz4llD; Wed, 3 Mar 2021 07:07:20 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 6943A2526C; Wed, 3 Mar 2021 07:07:20 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.16.1/8.16.1) with ESMTP id 12377KET000335; Wed, 3 Mar 2021 07:07:20 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 12377KRn000334; Wed, 3 Mar 2021 07:07:20 GMT (envelope-from git) Date: Wed, 3 Mar 2021 07:07:20 GMT Message-Id: <202103030707.12377KRn000334@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: Konstantin Belousov Subject: git: 06eba90acb62 - stable/12 - atomic: add atomic_interrupt_fence() MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: kib X-Git-Repository: src X-Git-Refname: refs/heads/stable/12 X-Git-Reftype: branch X-Git-Commit: 06eba90acb6201bbf2af76ca8acee5232abf9f82 Auto-Submitted: auto-generated X-BeenThere: dev-commits-src-branches@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Commits to the stable branches of the FreeBSD src repository List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 03 Mar 2021 07:07:20 -0000 The branch stable/12 has been updated by kib: URL: https://cgit.FreeBSD.org/src/commit/?id=06eba90acb6201bbf2af76ca8acee5232abf9f82 commit 06eba90acb6201bbf2af76ca8acee5232abf9f82 Author: Konstantin Belousov AuthorDate: 2021-02-23 22:12:29 +0000 Commit: Konstantin Belousov CommitDate: 2021-03-03 07:07:05 +0000 atomic: add atomic_interrupt_fence() (cherry picked from commit e2494f7561c852951d8ac567314f5e12f19ee7af) --- share/man/man9/atomic.9 | 13 ++++++++++++- sys/sys/atomic_common.h | 2 ++ 2 files changed, 14 insertions(+), 1 deletion(-) diff --git a/share/man/man9/atomic.9 b/share/man/man9/atomic.9 index 914da97764f0..7e72d127e168 100644 --- a/share/man/man9/atomic.9 +++ b/share/man/man9/atomic.9 @@ -22,7 +22,7 @@ .\" .\" $FreeBSD$ .\" -.Dd August 18, 2019 +.Dd February 24, 2021 .Dt ATOMIC 9 .Os .Sh NAME @@ -31,6 +31,7 @@ .Nm atomic_cmpset , .Nm atomic_fcmpset , .Nm atomic_fetchadd , +.Nm atomic_interrupt_fence , .Nm atomic_load , .Nm atomic_readandclear , .Nm atomic_set , @@ -59,6 +60,8 @@ .Fc .Ft .Fn atomic_fetchadd_ "volatile *p" " v" +.Ft void +.Fn atomic_interrupt_fence "void" .Ft .Fn atomic_load_[acq_] "volatile *p" .Ft @@ -290,6 +293,14 @@ release stores, by separating access from ordering, they can sometimes facilitate more efficient implementations of synchronization primitives. For example, they can be used to avoid executing a memory barrier until a memory access shows that some condition is satisfied. +.Ss Interrupt Fence Operations +The +.Fn atomic_interrupt_fence() +function establishes ordering between its call location and any interrupt +handler executing on the same CPU. +It is modeled after the similar C11 function +.Fn atomic_signal_fence() , +and adapted for the kernel environment. .Ss Multiple Processors In multiprocessor systems, the atomicity of the atomic operations on memory depends on support for cache coherence in the underlying architecture. diff --git a/sys/sys/atomic_common.h b/sys/sys/atomic_common.h index 16db4a81eb28..3d1920069362 100644 --- a/sys/sys/atomic_common.h +++ b/sys/sys/atomic_common.h @@ -70,4 +70,6 @@ (*(volatile uint64_t *)(p) = (uint64_t)(v)) #endif +#define atomic_interrupt_fence() __compiler_membar() + #endif