From owner-svn-src-all@freebsd.org Thu Dec 17 18:52:30 2020 Return-Path: Delivered-To: svn-src-all@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 D4DFC4C03BC; Thu, 17 Dec 2020 18:52:30 +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 TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 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 4Cxh265hDXz4b2j; Thu, 17 Dec 2020 18:52:30 +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 B668B1DA83; Thu, 17 Dec 2020 18:52:30 +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 0BHIqU45042268; Thu, 17 Dec 2020 18:52:30 GMT (envelope-from mjg@FreeBSD.org) Received: (from mjg@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id 0BHIqUBA042267; Thu, 17 Dec 2020 18:52:30 GMT (envelope-from mjg@FreeBSD.org) Message-Id: <202012171852.0BHIqUBA042267@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: mjg set sender to mjg@FreeBSD.org using -f From: Mateusz Guzik Date: Thu, 17 Dec 2020 18:52:30 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r368732 - head/sys/kern X-SVN-Group: head X-SVN-Commit-Author: mjg X-SVN-Commit-Paths: head/sys/kern X-SVN-Commit-Revision: 368732 X-SVN-Commit-Repository: base 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: 2.1.34 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 17 Dec 2020 18:52:30 -0000 Author: mjg Date: Thu Dec 17 18:52:30 2020 New Revision: 368732 URL: https://svnweb.freebsd.org/changeset/base/368732 Log: fd: reimplement close_range to avoid spurious relocking Modified: head/sys/kern/kern_descrip.c Modified: head/sys/kern/kern_descrip.c ============================================================================== --- head/sys/kern/kern_descrip.c Thu Dec 17 18:52:04 2020 (r368731) +++ head/sys/kern/kern_descrip.c Thu Dec 17 18:52:30 2020 (r368732) @@ -307,6 +307,7 @@ fdfree(struct filedesc *fdp, int fd) { struct filedescent *fde; + FILEDESC_XLOCK_ASSERT(fdp); fde = &fdp->fd_ofiles[fd]; #ifdef CAPABILITIES seqc_write_begin(&fde->fde_seqc); @@ -1367,12 +1368,10 @@ int kern_close_range(struct thread *td, u_int lowfd, u_int highfd) { struct filedesc *fdp; - int fd, ret, lastfile; + const struct fdescenttbl *fdt; + struct file *fp; + int fd; - ret = 0; - fdp = td->td_proc->p_fd; - FILEDESC_SLOCK(fdp); - /* * Check this prior to clamping; closefrom(3) with only fd 0, 1, and 2 * open should not be a usage error. From a close_range() perspective, @@ -1380,30 +1379,36 @@ kern_close_range(struct thread *td, u_int lowfd, u_int * be a usage error as all fd above 3 are in-fact already closed. */ if (highfd < lowfd) { - ret = EINVAL; - goto out; + return (EINVAL); } - /* - * If lastfile == -1, we're dealing with either a fresh file - * table or one in which every fd has been closed. Just return - * successful; there's nothing left to do. - */ - lastfile = fdlastfile(fdp); - if (lastfile == -1) - goto out; - /* Clamped to [lowfd, lastfile] */ - highfd = MIN(highfd, lastfile); - for (fd = lowfd; fd <= highfd; fd++) { - if (fdp->fd_ofiles[fd].fde_file != NULL) { - FILEDESC_SUNLOCK(fdp); - (void)kern_close(td, fd); - FILEDESC_SLOCK(fdp); + fdp = td->td_proc->p_fd; + FILEDESC_XLOCK(fdp); + fdt = atomic_load_ptr(&fdp->fd_files); + highfd = MIN(highfd, fdt->fdt_nfiles - 1); + fd = lowfd; + if (__predict_false(fd > highfd)) { + goto out_locked; + } + for (;;) { + fp = fdt->fdt_ofiles[fd].fde_file; + if (fp == NULL) { + if (fd == highfd) + goto out_locked; + } else { + fdfree(fdp, fd); + (void) closefp(fdp, fd, fp, td, true, true); + if (fd == highfd) + goto out_unlocked; + FILEDESC_XLOCK(fdp); + fdt = atomic_load_ptr(&fdp->fd_files); } + fd++; } -out: - FILEDESC_SUNLOCK(fdp); - return (ret); +out_locked: + FILEDESC_XUNLOCK(fdp); +out_unlocked: + return (0); } #ifndef _SYS_SYSPROTO_H_