From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51653) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bwVoY-0003tX-O8 for qemu-devel@nongnu.org; Tue, 18 Oct 2016 10:56:27 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bwVoV-0007Xa-If for qemu-devel@nongnu.org; Tue, 18 Oct 2016 10:56:26 -0400 Received: from mail-yb0-x244.google.com ([2607:f8b0:4002:c09::244]:34573) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1bwVoV-0007XD-CE for qemu-devel@nongnu.org; Tue, 18 Oct 2016 10:56:23 -0400 Received: by mail-yb0-x244.google.com with SMTP id 191so4476842ybv.1 for ; Tue, 18 Oct 2016 07:56:23 -0700 (PDT) From: Pranith Kumar Date: Tue, 18 Oct 2016 10:56:19 -0400 Message-Id: <20161018145620.20658-1-bobby.prani@gmail.com> Subject: [Qemu-devel] [PATCH 1/2] docs/rcu: Distinguish rcu_dereference and atomic_rcu_read List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini , Sergey Fedorov , Cao jin , "open list:All patches CC here" 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 -- 2.10.1