From owner-svn-src-all@freebsd.org  Thu Feb 23 09:53:55 2017
Return-Path: <owner-svn-src-all@freebsd.org>
Delivered-To: svn-src-all@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 87B8DCE874D;
 Thu, 23 Feb 2017 09:53:55 +0000 (UTC)
 (envelope-from hselasky@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 56E401A2E;
 Thu, 23 Feb 2017 09:53:55 +0000 (UTC)
 (envelope-from hselasky@FreeBSD.org)
Received: from repo.freebsd.org ([127.0.1.37])
 by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id v1N9rs4o087347;
 Thu, 23 Feb 2017 09:53:54 GMT (envelope-from hselasky@FreeBSD.org)
Received: (from hselasky@localhost)
 by repo.freebsd.org (8.15.2/8.15.2/Submit) id v1N9rsuR087346;
 Thu, 23 Feb 2017 09:53:54 GMT (envelope-from hselasky@FreeBSD.org)
Message-Id: <201702230953.v1N9rsuR087346@repo.freebsd.org>
X-Authentication-Warning: repo.freebsd.org: hselasky set sender to
 hselasky@FreeBSD.org using -f
From: Hans Petter Selasky <hselasky@FreeBSD.org>
Date: Thu, 23 Feb 2017 09:53:54 +0000 (UTC)
To: src-committers@freebsd.org, svn-src-all@freebsd.org,
 svn-src-head@freebsd.org
Subject: svn commit: r314136 - head/sys/compat/linuxkpi/common/include/linux
X-SVN-Group: head
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
X-BeenThere: svn-src-all@freebsd.org
X-Mailman-Version: 2.1.23
Precedence: list
List-Id: "SVN commit messages for the entire src tree \(except for &quot;
 user&quot; and &quot; projects&quot; \)" <svn-src-all.freebsd.org>
List-Unsubscribe: <https://lists.freebsd.org/mailman/options/svn-src-all>,
 <mailto:svn-src-all-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/svn-src-all/>
List-Post: <mailto:svn-src-all@freebsd.org>
List-Help: <mailto:svn-src-all-request@freebsd.org?subject=help>
List-Subscribe: <https://lists.freebsd.org/mailman/listinfo/svn-src-all>,
 <mailto:svn-src-all-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Thu, 23 Feb 2017 09:53:55 -0000

Author: hselasky
Date: Thu Feb 23 09:53:54 2017
New Revision: 314136
URL: https://svnweb.freebsd.org/changeset/base/314136

Log:
  Implement __test_and_clear_bit() and __test_and_set_bit() in the LinuxKPI.
  
  The clang compiler will optimise these functions down to three AMD64
  instructions if the bit argument is a constant during compilation.
  
  MFC after:		1 week
  Sponsored by:		Mellanox Technologies

Modified:
  head/sys/compat/linuxkpi/common/include/linux/bitops.h

Modified: head/sys/compat/linuxkpi/common/include/linux/bitops.h
==============================================================================
--- head/sys/compat/linuxkpi/common/include/linux/bitops.h	Thu Feb 23 09:52:22 2017	(r314135)
+++ head/sys/compat/linuxkpi/common/include/linux/bitops.h	Thu Feb 23 09:53:54 2017	(r314136)
@@ -338,6 +338,21 @@ test_and_clear_bit(long bit, volatile un
 }
 
 static inline int
+__test_and_clear_bit(long bit, volatile unsigned long *var)
+{
+	long val;
+
+	var += BIT_WORD(bit);
+	bit %= BITS_PER_LONG;
+	bit = (1UL << bit);
+
+	val = *var;
+	*var &= ~bit;
+
+	return !!(val & bit);
+}
+
+static inline int
 test_and_set_bit(long bit, volatile unsigned long *var)
 {
 	long val;
@@ -352,6 +367,21 @@ test_and_set_bit(long bit, volatile unsi
 	return !!(val & bit);
 }
 
+static inline int
+__test_and_set_bit(long bit, volatile unsigned long *var)
+{
+	long val;
+
+	var += BIT_WORD(bit);
+	bit %= BITS_PER_LONG;
+	bit = (1UL << bit);
+
+	val = *var;
+	*var |= bit;
+
+	return !!(val & bit);
+}
+
 static inline void
 bitmap_set(unsigned long *map, int start, int nr)
 {