Author: jeff Date: Thu Jan 23 05:23:37 2020 New Revision: 357028 URL: https://svnweb.freebsd.org/changeset/base/357028
Log: (fault 9/9) Move zero fill into a dedicated function to make the object lock state more clear. Reviewed by: kib Differential Revision: https://reviews.freebsd.org/D23326 Modified: head/sys/vm/vm_fault.c Modified: head/sys/vm/vm_fault.c ============================================================================== --- head/sys/vm/vm_fault.c Thu Jan 23 05:22:02 2020 (r357027) +++ head/sys/vm/vm_fault.c Thu Jan 23 05:23:37 2020 (r357028) @@ -960,35 +960,8 @@ vm_fault_next(struct faultstate *fs) */ VM_OBJECT_ASSERT_WLOCKED(fs->object); next_object = fs->object->backing_object; - if (next_object == NULL) { - /* - * If there's no object left, fill the page in the top - * object with zeros. - */ - VM_OBJECT_WUNLOCK(fs->object); - if (fs->object != fs->first_object) { - vm_object_pip_wakeup(fs->object); - fs->object = fs->first_object; - fs->pindex = fs->first_pindex; - } - MPASS(fs->first_m != NULL); - MPASS(fs->m == NULL); - fs->m = fs->first_m; - fs->first_m = NULL; - - /* - * Zero the page if necessary and mark it valid. - */ - if ((fs->m->flags & PG_ZERO) == 0) { - pmap_zero_page(fs->m); - } else { - VM_CNT_INC(v_ozfod); - } - VM_CNT_INC(v_zfod); - vm_page_valid(fs->m); - + if (next_object == NULL) return (false); - } MPASS(fs->first_m != NULL); KASSERT(fs->object != next_object, ("object loop %p", next_object)); VM_OBJECT_WLOCK(next_object); @@ -1002,6 +975,36 @@ vm_fault_next(struct faultstate *fs) return (true); } +static void +vm_fault_zerofill(struct faultstate *fs) +{ + + /* + * If there's no object left, fill the page in the top + * object with zeros. + */ + if (fs->object != fs->first_object) { + vm_object_pip_wakeup(fs->object); + fs->object = fs->first_object; + fs->pindex = fs->first_pindex; + } + MPASS(fs->first_m != NULL); + MPASS(fs->m == NULL); + fs->m = fs->first_m; + fs->first_m = NULL; + + /* + * Zero the page if necessary and mark it valid. + */ + if ((fs->m->flags & PG_ZERO) == 0) { + pmap_zero_page(fs->m); + } else { + VM_CNT_INC(v_ozfod); + } + VM_CNT_INC(v_zfod); + vm_page_valid(fs->m); +} + /* * Allocate a page directly or via the object populate method. */ @@ -1407,11 +1410,13 @@ RetryFault: * traverse into a backing object or zero fill if none is * found. */ - if (!vm_fault_next(&fs)) { - /* Don't try to prefault neighboring pages. */ - faultcount = 1; - break; /* break to PAGE HAS BEEN FOUND. */ - } + if (vm_fault_next(&fs)) + continue; + VM_OBJECT_WUNLOCK(fs.object); + vm_fault_zerofill(&fs); + /* Don't try to prefault neighboring pages. */ + faultcount = 1; + break; /* break to PAGE HAS BEEN FOUND. */ } /* _______________________________________________ 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"
