Author: jeff Date: Fri Nov 29 19:47:40 2019 New Revision: 355215 URL: https://svnweb.freebsd.org/changeset/base/355215
Log: Fix a perf regression from r355122. We can use a shared lock to drop the last ref on vnodes. Reviewed by: kib, markj Differential Revision: https://reviews.freebsd.org/D22565 Modified: head/sys/vm/vm_object.c Modified: head/sys/vm/vm_object.c ============================================================================== --- head/sys/vm/vm_object.c Fri Nov 29 18:05:54 2019 (r355214) +++ head/sys/vm/vm_object.c Fri Nov 29 19:47:40 2019 (r355215) @@ -520,15 +520,22 @@ static void vm_object_vndeallocate(vm_object_t object) { struct vnode *vp = (struct vnode *) object->handle; + bool last; KASSERT(object->type == OBJT_VNODE, ("vm_object_vndeallocate: not a vnode object")); KASSERT(vp != NULL, ("vm_object_vndeallocate: missing vp")); + /* Object lock to protect handle lookup. */ + last = refcount_release(&object->ref_count); + VM_OBJECT_RUNLOCK(object); + + if (!last) + return; + if (!umtx_shm_vnobj_persistent) umtx_shm_object_terminated(object); - VM_OBJECT_WUNLOCK(object); /* vrele may need the vnode lock. */ vrele(vp); } @@ -548,7 +555,7 @@ void vm_object_deallocate(vm_object_t object) { vm_object_t robject, temp; - bool last, released; + bool released; while (object != NULL) { /* @@ -565,18 +572,22 @@ vm_object_deallocate(vm_object_t object) if (released) return; - VM_OBJECT_WLOCK(object); - KASSERT(object->ref_count != 0, - ("vm_object_deallocate: object deallocated too many times: %d", object->type)); - - last = refcount_release(&object->ref_count); if (object->type == OBJT_VNODE) { - if (last) + VM_OBJECT_RLOCK(object); + if (object->type == OBJT_VNODE) { vm_object_vndeallocate(object); - else - VM_OBJECT_WUNLOCK(object); - return; + return; + } + VM_OBJECT_RUNLOCK(object); } + + VM_OBJECT_WLOCK(object); + KASSERT(object->ref_count > 0, + ("vm_object_deallocate: object deallocated too many times: %d", + object->type)); + + if (refcount_release(&object->ref_count)) + goto doterm; if (object->ref_count > 1) { VM_OBJECT_WUNLOCK(object); return; _______________________________________________ [email protected] mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "[email protected]"
