Date: Sat, 24 Jan 2026 00:32:24 +0000 From: Konstantin Belousov <kib@FreeBSD.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org Subject: git: a4123ac9f596 - stable/15 - vm_object: remove the charge member Message-ID: <69741318.a8f8.53ce1269@gitrepo.freebsd.org>
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The branch stable/15 has been updated by kib: URL: https://cgit.FreeBSD.org/src/commit/?id=a4123ac9f596415a090e74849b7a4bedf548f97b commit a4123ac9f596415a090e74849b7a4bedf548f97b Author: Konstantin Belousov <kib@FreeBSD.org> AuthorDate: 2026-01-03 09:34:23 +0000 Commit: Konstantin Belousov <kib@FreeBSD.org> CommitDate: 2026-01-24 00:26:45 +0000 vm_object: remove the charge member (cherry picked from commit d160447129fe060b28bcd6ba429d17afdf494ff2) --- sys/dev/md/md.c | 2 -- sys/kern/uipc_shm.c | 2 -- sys/vm/swap_pager.c | 8 ++------ sys/vm/vm_fault.c | 5 ++--- sys/vm/vm_map.c | 45 ++++++++++++++++++++++----------------------- sys/vm/vm_object.c | 46 +++++++++++++++++++++++++++------------------- sys/vm/vm_object.h | 4 +--- 7 files changed, 54 insertions(+), 58 deletions(-) diff --git a/sys/dev/md/md.c b/sys/dev/md/md.c index 9d246d7c78fd..8d2908264aac 100644 --- a/sys/dev/md/md.c +++ b/sys/dev/md/md.c @@ -1617,7 +1617,6 @@ mdresize(struct md_s *sc, struct md_req *mdr) 0, 0); swap_release_by_cred(IDX_TO_OFF(oldpages - newpages), sc->cred); - sc->s_swap.object->charge = IDX_TO_OFF(newpages); sc->s_swap.object->size = newpages; VM_OBJECT_WUNLOCK(sc->s_swap.object); } else if (newpages > oldpages) { @@ -1637,7 +1636,6 @@ mdresize(struct md_s *sc, struct md_req *mdr) } } VM_OBJECT_WLOCK(sc->s_swap.object); - sc->s_swap.object->charge = IDX_TO_OFF(newpages); sc->s_swap.object->size = newpages; VM_OBJECT_WUNLOCK(sc->s_swap.object); } diff --git a/sys/kern/uipc_shm.c b/sys/kern/uipc_shm.c index eb1327f7f2de..fe3feab4149f 100644 --- a/sys/kern/uipc_shm.c +++ b/sys/kern/uipc_shm.c @@ -759,7 +759,6 @@ shm_dotruncate_locked(struct shmfd *shmfd, off_t length, void *rl_cookie) /* Free the swap accounted for shm */ swap_release_by_cred(delta, object->cred); - object->charge -= delta; } else { if ((shmfd->shm_seals & F_SEAL_GROW) != 0) return (EPERM); @@ -768,7 +767,6 @@ shm_dotruncate_locked(struct shmfd *shmfd, off_t length, void *rl_cookie) delta = IDX_TO_OFF(nobjsize - object->size); if (!swap_reserve_by_cred(delta, object->cred)) return (ENOMEM); - object->charge += delta; } shmfd->shm_size = length; mtx_lock(&shm_timestamp_lock); diff --git a/sys/vm/swap_pager.c b/sys/vm/swap_pager.c index 3f077289ac30..efb0dd477c93 100644 --- a/sys/vm/swap_pager.c +++ b/sys/vm/swap_pager.c @@ -784,10 +784,7 @@ swap_pager_init_object(vm_object_t object, void *handle, struct ucred *cred, object->un_pager.swp.writemappings = 0; object->handle = handle; - if (cred != NULL) { - object->cred = cred; - object->charge = size; - } + object->cred = cred; return (true); } @@ -900,8 +897,7 @@ swap_pager_dealloc(vm_object_t object) * Release the allocation charge. */ if (object->cred != NULL) { - swap_release_by_cred(object->charge, object->cred); - object->charge = 0; + swap_release_by_cred(ptoa(object->size), object->cred); crfree(object->cred); object->cred = NULL; } diff --git a/sys/vm/vm_fault.c b/sys/vm/vm_fault.c index 1f13869aebf1..addda72e2b56 100644 --- a/sys/vm/vm_fault.c +++ b/sys/vm/vm_fault.c @@ -2310,13 +2310,12 @@ vm_fault_copy_entry(vm_map_t dst_map, vm_map_t src_map __unused, * directly. */ dst_object = vm_object_allocate_anon(atop(dst_entry->end - - dst_entry->start), NULL, NULL, 0); + dst_entry->start), NULL, NULL); #if VM_NRESERVLEVEL > 0 dst_object->flags |= OBJ_COLORED; dst_object->pg_color = atop(dst_entry->start); #endif dst_object->domain = src_object->domain; - dst_object->charge = dst_entry->end - dst_entry->start; dst_entry->object.vm_object = dst_object; dst_entry->offset = 0; @@ -2329,7 +2328,7 @@ vm_fault_copy_entry(vm_map_t dst_map, vm_map_t src_map __unused, ("vm_fault_copy_entry: leaked swp charge")); dst_object->cred = curthread->td_ucred; crhold(dst_object->cred); - *fork_charge += dst_object->charge; + *fork_charge += ptoa(dst_object->size); } else if ((dst_object->flags & OBJ_SWAP) != 0 && dst_object->cred == NULL) { KASSERT(dst_entry->cred != NULL, ("no cred for entry %p", diff --git a/sys/vm/vm_map.c b/sys/vm/vm_map.c index 4c33b786eaa0..04628f44a497 100644 --- a/sys/vm/vm_map.c +++ b/sys/vm/vm_map.c @@ -2428,7 +2428,7 @@ vm_map_entry_back(vm_map_entry_t entry) KASSERT((entry->eflags & MAP_ENTRY_IS_SUB_MAP) == 0, ("map entry %p is a submap", entry)); object = vm_object_allocate_anon(atop(entry->end - entry->start), NULL, - entry->cred, entry->end - entry->start); + entry->cred); entry->object.vm_object = object; entry->offset = 0; entry->cred = NULL; @@ -2443,21 +2443,26 @@ vm_map_entry_back(vm_map_entry_t entry) static inline void vm_map_entry_charge_object(vm_map_t map, vm_map_entry_t entry) { + vm_object_t object; VM_MAP_ASSERT_LOCKED(map); KASSERT((entry->eflags & MAP_ENTRY_IS_SUB_MAP) == 0, ("map entry %p is a submap", entry)); - if (entry->object.vm_object == NULL && !vm_map_is_system(map) && + object = entry->object.vm_object; + if (object == NULL && !vm_map_is_system(map) && (entry->eflags & MAP_ENTRY_GUARD) == 0) vm_map_entry_back(entry); - else if (entry->object.vm_object != NULL && + else if (object != NULL && ((entry->eflags & MAP_ENTRY_NEEDS_COPY) == 0) && entry->cred != NULL) { - VM_OBJECT_WLOCK(entry->object.vm_object); - KASSERT(entry->object.vm_object->cred == NULL, + VM_OBJECT_WLOCK(object); + KASSERT(object->cred == NULL, ("OVERCOMMIT: %s: both cred e %p", __func__, entry)); - entry->object.vm_object->cred = entry->cred; - entry->object.vm_object->charge = entry->end - entry->start; + object->cred = entry->cred; + if (entry->end - entry->start < ptoa(object->size)) { + swap_reserve_force_by_cred(ptoa(object->size) - + entry->end + entry->start, object->cred); + } VM_OBJECT_WUNLOCK(entry->object.vm_object); entry->cred = NULL; } @@ -2956,7 +2961,7 @@ again: * we cannot distinguish between non-charged and * charged clipped mapping of the same object later. */ - KASSERT(obj->charge == 0, + KASSERT(obj->cred == NULL, ("vm_map_protect: object %p overcharged (entry %p)", obj, entry)); if (!swap_reserve(ptoa(obj->size))) { @@ -2968,7 +2973,6 @@ again: crhold(cred); obj->cred = cred; - obj->charge = ptoa(obj->size); VM_OBJECT_WUNLOCK(obj); } @@ -3942,7 +3946,7 @@ static void vm_map_entry_delete(vm_map_t map, vm_map_entry_t entry) { vm_object_t object; - vm_pindex_t offidxstart, offidxend, size1; + vm_pindex_t offidxstart, offidxend, oldsize; vm_size_t size; vm_map_entry_unlink(map, entry, UNLINK_MERGE_NONE); @@ -3989,15 +3993,11 @@ vm_map_entry_delete(vm_map_t map, vm_map_entry_t entry) OBJPR_NOTMAPPED); if (offidxend >= object->size && offidxstart < object->size) { - size1 = object->size; + oldsize = object->size; object->size = offidxstart; if (object->cred != NULL) { - size1 -= object->size; - KASSERT(object->charge >= ptoa(size1), - ("object %p charge < 0", object)); - swap_release_by_cred(ptoa(size1), - object->cred); - object->charge -= ptoa(size1); + swap_release_by_cred(ptoa(oldsize - + ptoa(object->size)), object->cred); } } } @@ -4198,7 +4198,7 @@ vm_map_copy_swap_object(vm_map_entry_t src_entry, vm_map_entry_t dst_entry, ("OVERCOMMIT: vm_map_copy_anon_entry: cred %p", src_object)); src_object->cred = src_entry->cred; - src_object->charge = size; + *fork_charge += ptoa(src_object->size) - size; } dst_entry->object.vm_object = src_object; if (charged) { @@ -4455,7 +4455,7 @@ vmspace_fork(struct vmspace *vm1, vm_ooffset_t *fork_charge) KASSERT(object->cred == NULL, ("vmspace_fork both cred")); object->cred = old_entry->cred; - object->charge = old_entry->end - + *fork_charge += old_entry->end - old_entry->start; old_entry->cred = NULL; } @@ -5145,7 +5145,7 @@ RetryLookupLocked: if (vm_map_lock_upgrade(map)) goto RetryLookup; entry->object.vm_object = vm_object_allocate_anon(atop(size), - NULL, entry->cred, size); + NULL, entry->cred); entry->offset = 0; entry->cred = NULL; vm_map_lock_downgrade(map); @@ -5403,9 +5403,8 @@ vm_map_print(vm_map_t map) (void *)entry->object.vm_object, (uintmax_t)entry->offset); if (entry->object.vm_object && entry->object.vm_object->cred) - db_printf(", obj ruid %d charge %jx", - entry->object.vm_object->cred->cr_ruid, - (uintmax_t)entry->object.vm_object->charge); + db_printf(", obj ruid %d ", + entry->object.vm_object->cred->cr_ruid); if (entry->eflags & MAP_ENTRY_COW) db_printf(", copy (%s)", (entry->eflags & MAP_ENTRY_NEEDS_COPY) ? "needed" : "done"); diff --git a/sys/vm/vm_object.c b/sys/vm/vm_object.c index f4c54ba91742..aa2d7676e6a8 100644 --- a/sys/vm/vm_object.c +++ b/sys/vm/vm_object.c @@ -196,9 +196,9 @@ vm_object_zdtor(void *mem, int size, void *arg) KASSERT(object->type == OBJT_DEAD, ("object %p has non-dead type %d", object, object->type)); - KASSERT(object->charge == 0 && object->cred == NULL, - ("object %p has non-zero charge %ju (%p)", - object, (uintmax_t)object->charge, object->cred)); + KASSERT(object->cred == NULL, + ("object %p has non-zero charge cred %p", + object, object->cred)); } #endif @@ -254,7 +254,6 @@ _vm_object_allocate(objtype_t type, vm_pindex_t size, u_short flags, refcount_init(&object->ref_count, 1); object->memattr = VM_MEMATTR_DEFAULT; object->cred = NULL; - object->charge = 0; object->handle = handle; object->backing_object = NULL; object->backing_object_offset = (vm_ooffset_t) 0; @@ -452,7 +451,7 @@ vm_object_allocate_dyn(objtype_t dyntype, vm_pindex_t size, u_short flags) */ vm_object_t vm_object_allocate_anon(vm_pindex_t size, vm_object_t backing_object, - struct ucred *cred, vm_size_t charge) + struct ucred *cred) { vm_object_t handle, object; @@ -466,7 +465,6 @@ vm_object_allocate_anon(vm_pindex_t size, vm_object_t backing_object, _vm_object_allocate(OBJT_SWAP, size, OBJ_ANON | OBJ_ONEMAPPING | OBJ_SWAP, object, handle); object->cred = cred; - object->charge = cred != NULL ? charge : 0; return (object); } @@ -1448,7 +1446,7 @@ vm_object_shadow(vm_object_t *object, vm_ooffset_t *offset, vm_size_t length, /* * Allocate a new object with the given length. */ - result = vm_object_allocate_anon(atop(length), source, cred, length); + result = vm_object_allocate_anon(atop(length), source, cred); /* * Store the offset into the source object, and fix up the offset into @@ -1511,6 +1509,7 @@ vm_object_split(vm_map_entry_t entry) struct pctrie_iter pages; vm_page_t m; vm_object_t orig_object, new_object, backing_object; + struct ucred *cred; vm_pindex_t offidxstart; vm_size_t size; @@ -1525,9 +1524,26 @@ vm_object_split(vm_map_entry_t entry) offidxstart = OFF_TO_IDX(entry->offset); size = atop(entry->end - entry->start); + if (orig_object->cred != NULL) { + /* + * vm_object_split() is currently called from + * vmspace_fork(), and it might be tempting to add the + * charge for the split object to fork_charge. But + * fork_charge is discharged on error when the copied + * vmspace is destroyed. Since the split object is + * inserted into the shadow hierarchy serving the + * source vm_map, it is kept even after the + * unsuccessful fork, meaning that we have to force + * its swap usage. + */ + cred = curthread->td_ucred; + crhold(cred); + swap_reserve_force_by_cred(ptoa(size), cred); + } else { + cred = NULL; + } - new_object = vm_object_allocate_anon(size, orig_object, - orig_object->cred, ptoa(size)); + new_object = vm_object_allocate_anon(size, orig_object, cred); /* * We must wait for the orig_object to complete any in-progress @@ -1550,12 +1566,6 @@ vm_object_split(vm_map_entry_t entry) new_object->backing_object_offset = orig_object->backing_object_offset + entry->offset; } - if (orig_object->cred != NULL) { - crhold(orig_object->cred); - KASSERT(orig_object->charge >= ptoa(size), - ("orig_object->charge < 0")); - orig_object->charge -= ptoa(size); - } /* * Mark the split operation so that swap_pager_getpages() knows @@ -2233,7 +2243,6 @@ vm_object_coalesce(vm_object_t prev_object, vm_ooffset_t prev_offset, swap_release_by_cred(ptoa(prev_object->size - next_pindex), prev_object->cred); } - prev_object->charge += charge; } else if ((cflags & OBJCO_CHARGED) != 0) { /* * The caller charged, but the object has @@ -2786,9 +2795,8 @@ DB_SHOW_COMMAND(object, vm_object_print_static) db_iprintf("Object %p: type=%d, size=0x%jx, res=%d, ref=%d, flags=0x%x", object, (int)object->type, (uintmax_t)object->size, object->resident_page_count, object->ref_count, object->flags); - db_iprintf(" ruid %d charge %jx\n", - object->cred ? object->cred->cr_ruid : -1, - (uintmax_t)object->charge); + db_iprintf(" ruid %d\n", + object->cred ? object->cred->cr_ruid : -1); db_iprintf(" sref=%d, backing_object(%d)=(%p)+0x%jx\n", atomic_load_int(&object->shadow_count), object->backing_object ? object->backing_object->ref_count : 0, diff --git a/sys/vm/vm_object.h b/sys/vm/vm_object.h index fdc0bcfc9f28..b056ebe9a4b7 100644 --- a/sys/vm/vm_object.h +++ b/sys/vm/vm_object.h @@ -175,7 +175,6 @@ struct vm_object { } phys; } un_pager; struct ucred *cred; - vm_ooffset_t charge; void *umtx_data; }; @@ -358,8 +357,7 @@ void umtx_shm_object_terminated(vm_object_t object); extern int umtx_shm_vnobj_persistent; vm_object_t vm_object_allocate (objtype_t, vm_pindex_t); -vm_object_t vm_object_allocate_anon(vm_pindex_t, vm_object_t, struct ucred *, - vm_size_t); +vm_object_t vm_object_allocate_anon(vm_pindex_t, vm_object_t, struct ucred *); vm_object_t vm_object_allocate_dyn(objtype_t, vm_pindex_t, u_short); boolean_t vm_object_coalesce(vm_object_t, vm_ooffset_t, vm_size_t, vm_size_t, int);home | help
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