From owner-svn-src-head@freebsd.org Wed Feb 15 23:33:15 2017 Return-Path: Delivered-To: svn-src-head@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id A368BCE004A; Wed, 15 Feb 2017 23:33:15 +0000 (UTC) (envelope-from mjg@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 733BC669; Wed, 15 Feb 2017 23:33:15 +0000 (UTC) (envelope-from mjg@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id v1FNXEV0097302; Wed, 15 Feb 2017 23:33:14 GMT (envelope-from mjg@FreeBSD.org) Received: (from mjg@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id v1FNXE1u097301; Wed, 15 Feb 2017 23:33:14 GMT (envelope-from mjg@FreeBSD.org) Message-Id: <201702152333.v1FNXE1u097301@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: mjg set sender to mjg@FreeBSD.org using -f From: Mateusz Guzik Date: Wed, 15 Feb 2017 23:33:14 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r313784 - head/sys/sys X-SVN-Group: head MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 15 Feb 2017 23:33:15 -0000 Author: mjg Date: Wed Feb 15 23:33:14 2017 New Revision: 313784 URL: https://svnweb.freebsd.org/changeset/base/313784 Log: rwlock: tidy up r313392 While a new bit was added and thread alignment got shifted to accomodate it, RW_READERS_SHIFT was not modified accordingly and clashed with the new flag. This was surprisingly harmless. If the lock was taken for writing, other flags were tested. If the lock was taken for reading, it would correctly work for readers > 1 and this was the only relevant test performed. Modified: head/sys/sys/rwlock.h Modified: head/sys/sys/rwlock.h ============================================================================== --- head/sys/sys/rwlock.h Wed Feb 15 23:04:25 2017 (r313783) +++ head/sys/sys/rwlock.h Wed Feb 15 23:33:14 2017 (r313784) @@ -65,7 +65,7 @@ #define RW_LOCK_WAITERS (RW_LOCK_READ_WAITERS | RW_LOCK_WRITE_WAITERS) #define RW_OWNER(x) ((x) & ~RW_LOCK_FLAGMASK) -#define RW_READERS_SHIFT 4 +#define RW_READERS_SHIFT 5 #define RW_READERS(x) (RW_OWNER((x)) >> RW_READERS_SHIFT) #define RW_READERS_LOCK(x) ((x) << RW_READERS_SHIFT | RW_LOCK_READ) #define RW_ONE_READER (1 << RW_READERS_SHIFT)