From owner-svn-src-head@freebsd.org Mon May 4 10:10:08 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 670A22CB431; Mon, 4 May 2020 10:10:08 +0000 (UTC) (envelope-from hselasky@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 49FzB826Dkz404x; Mon, 4 May 2020 10:10:08 +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 mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 43904226B2; Mon, 4 May 2020 10:10:08 +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 044AA82F065437; Mon, 4 May 2020 10:10:08 GMT (envelope-from hselasky@FreeBSD.org) Received: (from hselasky@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id 044AA8wZ065436; Mon, 4 May 2020 10:10:08 GMT (envelope-from hselasky@FreeBSD.org) Message-Id: <202005041010.044AA8wZ065436@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: hselasky set sender to hselasky@FreeBSD.org using -f From: Hans Petter Selasky Date: Mon, 4 May 2020 10:10:08 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r360623 - head/sys/compat/linuxkpi/common/include/linux X-SVN-Group: head X-SVN-Commit-Author: hselasky X-SVN-Commit-Paths: head/sys/compat/linuxkpi/common/include/linux X-SVN-Commit-Revision: 360623 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, 04 May 2020 10:10:08 -0000 Author: hselasky Date: Mon May 4 10:10:07 2020 New Revision: 360623 URL: https://svnweb.freebsd.org/changeset/base/360623 Log: Optimise use of sg_page_count() in __sg_page_iter_next() in the LinuxKPI. No need to compute value twice. No functional change intended. MFC after: 1 week Sponsored by: Mellanox Technologies Modified: head/sys/compat/linuxkpi/common/include/linux/scatterlist.h Modified: head/sys/compat/linuxkpi/common/include/linux/scatterlist.h ============================================================================== --- head/sys/compat/linuxkpi/common/include/linux/scatterlist.h Mon May 4 09:58:45 2020 (r360622) +++ head/sys/compat/linuxkpi/common/include/linux/scatterlist.h Mon May 4 10:10:07 2020 (r360623) @@ -416,6 +416,8 @@ sg_page_count(struct scatterlist *sg) static inline bool __sg_page_iter_next(struct sg_page_iter *piter) { + unsigned int pgcount; + if (piter->internal.nents == 0) return (0); if (piter->sg == NULL) @@ -424,8 +426,11 @@ __sg_page_iter_next(struct sg_page_iter *piter) piter->sg_pgoffset += piter->internal.pg_advance; piter->internal.pg_advance = 1; - while (piter->sg_pgoffset >= sg_page_count(piter->sg)) { - piter->sg_pgoffset -= sg_page_count(piter->sg); + while (1) { + pgcount = sg_page_count(piter->sg); + if (likely(piter->sg_pgoffset < pgcount)) + break; + piter->sg_pgoffset -= pgcount; piter->sg = sg_next(piter->sg); if (--piter->internal.nents == 0) return (0);