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[73.207.178.95]) by smtp.gmail.com with ESMTPSA id w141sm13845574yww.35.2016.10.18.07.56.21 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Tue, 18 Oct 2016 07:56:21 -0700 (PDT) From: Pranith Kumar To: Paolo Bonzini , Sergey Fedorov , Cao jin , qemu-devel@nongnu.org (open list:All patches CC here) Date: Tue, 18 Oct 2016 10:56:19 -0400 Message-Id: <20161018145620.20658-1-bobby.prani@gmail.com> X-Mailer: git-send-email 2.10.1 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 2607:f8b0:4002:c09::244 Subject: [Qemu-devel] [PATCH 1/2] docs/rcu: Distinguish rcu_dereference and atomic_rcu_read X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP Signed-off-by: Pranith Kumar --- docs/rcu.txt | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/docs/rcu.txt b/docs/rcu.txt index c84e7f4..c177dcb 100644 --- a/docs/rcu.txt +++ b/docs/rcu.txt @@ -197,7 +197,9 @@ DIFFERENCES WITH LINUX critical section to become an updater. - atomic_rcu_read and atomic_rcu_set replace rcu_dereference and - rcu_assign_pointer. They take a _pointer_ to the variable being accessed. + rcu_assign_pointer. Note that although both atomic_rcu_read and + rcu_dereference take a _pointer_ to the variable being accessed, + atomic_rcu_read dereferences the pointer whereas rcu_dereference does not. - call_rcu is a macro that has an extra argument (the name of the first field in the struct, which must be a struct rcu_head), and expects the