From owner-svn-src-head@freebsd.org Mon Feb 10 00:05:05 2020 Return-Path: Delivered-To: svn-src-head@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 98E492466C9; Mon, 10 Feb 2020 00:05:05 +0000 (UTC) (envelope-from ian@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) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 48G5kn3RFpz3Dfs; Mon, 10 Feb 2020 00:05:05 +0000 (UTC) (envelope-from ian@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 mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 6B6B3E75A; Mon, 10 Feb 2020 00:05:05 +0000 (UTC) (envelope-from ian@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id 01A0555p041408; Mon, 10 Feb 2020 00:05:05 GMT (envelope-from ian@FreeBSD.org) Received: (from ian@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id 01A055SJ041407; Mon, 10 Feb 2020 00:05:05 GMT (envelope-from ian@FreeBSD.org) Message-Id: <202002100005.01A055SJ041407@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: ian set sender to ian@FreeBSD.org using -f From: Ian Lepore Date: Mon, 10 Feb 2020 00:05:05 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r357709 - head/sys/arm/include X-SVN-Group: head X-SVN-Commit-Author: ian X-SVN-Commit-Paths: head/sys/arm/include X-SVN-Commit-Revision: 357709 X-SVN-Commit-Repository: base 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: 2.1.29 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: Mon, 10 Feb 2020 00:05:05 -0000 Author: ian Date: Mon Feb 10 00:05:04 2020 New Revision: 357709 URL: https://svnweb.freebsd.org/changeset/base/357709 Log: Implement atomic_testandclear_{32,int,long} for 32-bit arm. Also, replace the existing implementation of atomic_testandset with the same new algorithm, which uses fewer instructions and fewer registers. Modified: head/sys/arm/include/atomic-v6.h Modified: head/sys/arm/include/atomic-v6.h ============================================================================== --- head/sys/arm/include/atomic-v6.h Sun Feb 9 22:40:05 2020 (r357708) +++ head/sys/arm/include/atomic-v6.h Mon Feb 10 00:05:04 2020 (r357709) @@ -858,23 +858,75 @@ atomic_store_rel_long(volatile u_long *p, u_long v) } static __inline int -atomic_testandset_32(volatile uint32_t *p, u_int v) +atomic_testandclear_32(volatile uint32_t *ptr, u_int bit) { - uint32_t tmp, tmp2, res, mask; + int newv, oldv, result; - mask = 1u << (v & 0x1f); - tmp = tmp2 = 0; __asm __volatile( - "1: ldrex %0, [%4] \n" - " orr %1, %0, %3 \n" - " strex %2, %1, [%4] \n" - " cmp %2, #0 \n" - " it ne \n" - " bne 1b \n" - : "=&r" (res), "=&r" (tmp), "=&r" (tmp2) - : "r" (mask), "r" (p) - : "cc", "memory"); - return ((res & mask) != 0); + " mov ip, #1 \n" + " lsl ip, ip, %[bit] \n" + /* Done with %[bit] as input, reuse below as output. */ + "1: \n" + " ldrex %[oldv], [%[ptr]] \n" + " bic %[newv], %[oldv], ip \n" + " strex %[bit], %[newv], [%[ptr]] \n" + " teq %[bit], #0 \n" + " it ne \n" + " bne 1b \n" + " ands %[bit], %[oldv], ip \n" + " it ne \n" + " movne %[bit], #1 \n" + : [bit] "=&r" (result), + [oldv] "=&r" (oldv), + [newv] "=&r" (newv) + : [ptr] "r" (ptr), + "[bit]" (bit) + : "cc", "ip", "memory"); + + return (result); +} + +static __inline int +atomic_testandclear_int(volatile u_int *p, u_int v) +{ + + return (atomic_testandclear_32((volatile uint32_t *)p, v)); +} + +static __inline int +atomic_testandclear_long(volatile u_long *p, u_int v) +{ + + return (atomic_testandclear_32((volatile uint32_t *)p, v)); +} + +static __inline int +atomic_testandset_32(volatile uint32_t *ptr, u_int bit) +{ + int newv, oldv, result; + + __asm __volatile( + " mov ip, #1 \n" + " lsl ip, ip, %[bit] \n" + /* Done with %[bit] as input, reuse below as output. */ + "1: \n" + " ldrex %[oldv], [%[ptr]] \n" + " orr %[newv], %[oldv], ip \n" + " strex %[bit], %[newv], [%[ptr]] \n" + " teq %[bit], #0 \n" + " it ne \n" + " bne 1b \n" + " ands %[bit], %[oldv], ip \n" + " it ne \n" + " movne %[bit], #1 \n" + : [bit] "=&r" (result), + [oldv] "=&r" (oldv), + [newv] "=&r" (newv) + : [ptr] "r" (ptr), + "[bit]" (bit) + : "cc", "ip", "memory"); + + return (result); } static __inline int