From owner-svn-src-head@freebsd.org Fri Dec 7 16:22:55 2018 Return-Path: Delivered-To: svn-src-head@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 9AFF01312A64; Fri, 7 Dec 2018 16:22:55 +0000 (UTC) (envelope-from mjg@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 3C54D6C186; Fri, 7 Dec 2018 16:22:55 +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 mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 17FF01586C; Fri, 7 Dec 2018 16:22:55 +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 wB7GMsvJ072169; Fri, 7 Dec 2018 16:22:54 GMT (envelope-from mjg@FreeBSD.org) Received: (from mjg@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id wB7GMsUo072168; Fri, 7 Dec 2018 16:22:54 GMT (envelope-from mjg@FreeBSD.org) Message-Id: <201812071622.wB7GMsUo072168@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: mjg set sender to mjg@FreeBSD.org using -f From: Mateusz Guzik Date: Fri, 7 Dec 2018 16:22:54 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r341699 - head/sys/vm X-SVN-Group: head X-SVN-Commit-Author: mjg X-SVN-Commit-Paths: head/sys/vm X-SVN-Commit-Revision: 341699 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: 3C54D6C186 X-Spamd-Result: default: False [-2.94 / 15.00]; local_wl_from(0.00)[FreeBSD.org]; NEURAL_HAM_MEDIUM(-0.99)[-0.988,0]; NEURAL_HAM_SHORT(-0.96)[-0.964,0]; NEURAL_HAM_LONG(-0.99)[-0.990,0]; ASN(0.00)[asn:11403, ipnet:2610:1c1:1::/48, country:US] X-Rspamd-Server: mx1.freebsd.org 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: Fri, 07 Dec 2018 16:22:55 -0000 Author: mjg Date: Fri Dec 7 16:22:54 2018 New Revision: 341699 URL: https://svnweb.freebsd.org/changeset/base/341699 Log: vm: use fcmpset for vmspace reference counting Sponsored by: The FreeBSD Foundation Modified: head/sys/vm/vm_map.c Modified: head/sys/vm/vm_map.c ============================================================================== --- head/sys/vm/vm_map.c Fri Dec 7 16:11:45 2018 (r341698) +++ head/sys/vm/vm_map.c Fri Dec 7 16:22:54 2018 (r341699) @@ -391,8 +391,8 @@ vmspace_exit(struct thread *td) p = td->td_proc; vm = p->p_vmspace; atomic_add_int(&vmspace0.vm_refcnt, 1); + refcnt = vm->vm_refcnt; do { - refcnt = vm->vm_refcnt; if (refcnt > 1 && p->p_vmspace != &vmspace0) { /* Switch now since other proc might free vmspace */ PROC_VMSPACE_LOCK(p); @@ -400,7 +400,7 @@ vmspace_exit(struct thread *td) PROC_VMSPACE_UNLOCK(p); pmap_activate(td); } - } while (!atomic_cmpset_int(&vm->vm_refcnt, refcnt, refcnt - 1)); + } while (!atomic_fcmpset_int(&vm->vm_refcnt, &refcnt, refcnt - 1)); if (refcnt == 1) { if (p->p_vmspace != vm) { /* vmspace not yet freed, switch back */ @@ -437,13 +437,13 @@ vmspace_acquire_ref(struct proc *p) PROC_VMSPACE_UNLOCK(p); return (NULL); } + refcnt = vm->vm_refcnt; do { - refcnt = vm->vm_refcnt; if (refcnt <= 0) { /* Avoid 0->1 transition */ PROC_VMSPACE_UNLOCK(p); return (NULL); } - } while (!atomic_cmpset_int(&vm->vm_refcnt, refcnt, refcnt + 1)); + } while (!atomic_fcmpset_int(&vm->vm_refcnt, &refcnt, refcnt + 1)); if (vm != p->p_vmspace) { PROC_VMSPACE_UNLOCK(p); vmspace_free(vm);