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 <rli...@gmail.com> 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_ */ _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
