From owner-svn-src-all@freebsd.org Thu Dec 17 17:48:59 2015 Return-Path: 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 6E944A4A897; Thu, 17 Dec 2015 17:48:59 +0000 (UTC) (envelope-from cem@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 2398918E1; Thu, 17 Dec 2015 17:48:59 +0000 (UTC) (envelope-from cem@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id tBHHmwxD037352; Thu, 17 Dec 2015 17:48:58 GMT (envelope-from cem@FreeBSD.org) Received: (from cem@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id tBHHmvAC037349; Thu, 17 Dec 2015 17:48:57 GMT (envelope-from cem@FreeBSD.org) Message-Id: <201512171748.tBHHmvAC037349@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: cem set sender to cem@FreeBSD.org using -f From: "Conrad E. Meyer" Date: Thu, 17 Dec 2015 17:48:57 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r292406 - head/sys/vm 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: 2.1.20 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 2015 17:48:59 -0000 Author: cem Date: Thu Dec 17 17:48:57 2015 New Revision: 292406 URL: https://svnweb.freebsd.org/changeset/base/292406 Log: vm_page_replace: add wrapper to KASSERT about old page It turns out the callers of vm_page_replace know exactly which page they are replacing and would like to assert about it. Change those from hard panics to KASSERTs, and provide them with a wrapper so they don't have to deal with warnings from an INVARIANTS-dependent dead store of the return value of vm_page_replace. Submitted by: Ryan Libby Reviewed by: alc, kib (earlier version) Sponsored by: EMC / Isilon Storage Division Differential Revision: https://reviews.freebsd.org/D4497 Modified: head/sys/vm/device_pager.c head/sys/vm/sg_pager.c head/sys/vm/vm_page.h Modified: head/sys/vm/device_pager.c ============================================================================== --- head/sys/vm/device_pager.c Thu Dec 17 17:00:04 2015 (r292405) +++ head/sys/vm/device_pager.c Thu Dec 17 17:48:57 2015 (r292406) @@ -347,8 +347,7 @@ old_dev_pager_fault(vm_object_t object, */ page = vm_page_getfake(paddr, memattr); VM_OBJECT_WLOCK(object); - if (vm_page_replace(page, object, (*mres)->pindex) != *mres) - panic("old_dev_pager_fault: invalid page replacement"); + vm_page_replace_checked(page, object, (*mres)->pindex, *mres); vm_page_lock(*mres); vm_page_free(*mres); vm_page_unlock(*mres); Modified: head/sys/vm/sg_pager.c ============================================================================== --- head/sys/vm/sg_pager.c Thu Dec 17 17:00:04 2015 (r292405) +++ head/sys/vm/sg_pager.c Thu Dec 17 17:48:57 2015 (r292406) @@ -188,8 +188,7 @@ sg_pager_getpages(vm_object_t object, vm page = vm_page_getfake(paddr, memattr); VM_OBJECT_WLOCK(object); TAILQ_INSERT_TAIL(&object->un_pager.sgp.sgp_pglist, page, plinks.q); - if (vm_page_replace(page, object, offset) != m[0]) - panic("sg_pager_getpages: invalid place replacement"); + vm_page_replace_checked(page, object, offset, m[0]); m[0] = page; page->valid = VM_PAGE_BITS_ALL; Modified: head/sys/vm/vm_page.h ============================================================================== --- head/sys/vm/vm_page.h Thu Dec 17 17:00:04 2015 (r292405) +++ head/sys/vm/vm_page.h Thu Dec 17 17:48:57 2015 (r292406) @@ -678,5 +678,20 @@ vm_page_undirty(vm_page_t m) m->dirty = 0; } +static inline void +vm_page_replace_checked(vm_page_t mnew, vm_object_t object, vm_pindex_t pindex, + vm_page_t mold) +{ + vm_page_t mret; + + mret = vm_page_replace(mnew, object, pindex); + KASSERT(mret == mold, + ("invalid page replacement, mold=%p, mret=%p", mold, mret)); + + /* Unused if !INVARIANTS. */ + (void)mold; + (void)mret; +} + #endif /* _KERNEL */ #endif /* !_VM_PAGE_ */