aboutsummaryrefslogtreecommitdiffstats
path: root/erts/emulator/beam/erl_db_hash.c
diff options
context:
space:
mode:
Diffstat (limited to 'erts/emulator/beam/erl_db_hash.c')
-rw-r--r--erts/emulator/beam/erl_db_hash.c76
1 files changed, 42 insertions, 34 deletions
diff --git a/erts/emulator/beam/erl_db_hash.c b/erts/emulator/beam/erl_db_hash.c
index 81b0c4465c..cff65f244d 100644
--- a/erts/emulator/beam/erl_db_hash.c
+++ b/erts/emulator/beam/erl_db_hash.c
@@ -148,8 +148,11 @@ static ERTS_INLINE Uint hash_to_ix(DbTableHash* tb, HashValue hval)
}
/* Remember a slot containing a pseudo-deleted item (INVALID_HASH)
-*/
-static ERTS_INLINE void add_fixed_deletion(DbTableHash* tb, int ix)
+ * Return false if we got raced by unfixing thread
+ * and the object should be deleted for real.
+ */
+static ERTS_INLINE int add_fixed_deletion(DbTableHash* tb, int ix,
+ erts_aint_t fixated_by_me)
{
erts_aint_t was_next;
erts_aint_t exp_next;
@@ -160,12 +163,18 @@ static ERTS_INLINE void add_fixed_deletion(DbTableHash* tb, int ix)
fixd->slot = ix;
was_next = erts_smp_atomic_read_acqb(&tb->fixdel);
do { /* Lockless atomic insertion in linked list: */
- exp_next = was_next;
+ if (NFIXED(tb) <= fixated_by_me) {
+ erts_db_free(ERTS_ALC_T_DB_FIX_DEL, (DbTable*)tb,
+ fixd, sizeof(FixedDeletion));
+ return 0; /* raced by unfixer */
+ }
+ exp_next = was_next;
fixd->next = (FixedDeletion*) exp_next;
- was_next = erts_smp_atomic_cmpxchg_relb(&tb->fixdel,
- (erts_aint_t) fixd,
- exp_next);
+ was_next = erts_smp_atomic_cmpxchg_mb(&tb->fixdel,
+ (erts_aint_t) fixd,
+ exp_next);
}while (was_next != exp_next);
+ return 1;
}
@@ -460,9 +469,6 @@ static ERTS_INLINE void try_shrink(DbTableHash* tb)
}
}
-#define EQ_REL(x,y,y_base) \
- (is_same(x,NULL,y,y_base) || (is_not_both_immed((x),(y)) && eq_rel((x),NULL,(y),y_base)))
-
/* Is this a live object (not pseodo-deleted) with the specified key?
*/
static ERTS_INLINE int has_live_key(DbTableHash* tb, HashDbTerm* b,
@@ -472,7 +478,7 @@ static ERTS_INLINE int has_live_key(DbTableHash* tb, HashDbTerm* b,
else {
Eterm itemKey = GETKEY(tb, b->dbterm.tpl);
ASSERT(!is_header(itemKey));
- return EQ_REL(key, itemKey, b->dbterm.tpl);
+ return EQ(key, itemKey);
}
}
@@ -485,7 +491,7 @@ static ERTS_INLINE int has_key(DbTableHash* tb, HashDbTerm* b,
else {
Eterm itemKey = GETKEY(tb, b->dbterm.tpl);
ASSERT(!is_header(itemKey));
- return EQ_REL(key, itemKey, b->dbterm.tpl);
+ return EQ(key, itemKey);
}
}
@@ -607,8 +613,8 @@ void db_unfix_table_hash(DbTableHash *tb)
|| (erts_smp_lc_rwmtx_is_rlocked(&tb->common.rwlock)
&& !tb->common.is_thread_safe));
restart:
- fixdel = (FixedDeletion*) erts_smp_atomic_xchg_acqb(&tb->fixdel,
- (erts_aint_t) NULL);
+ fixdel = (FixedDeletion*) erts_smp_atomic_xchg_mb(&tb->fixdel,
+ (erts_aint_t) NULL);
while (fixdel != NULL) {
FixedDeletion *fx = fixdel;
int ix = fx->slot;
@@ -1142,9 +1148,9 @@ int db_erase_hash(DbTable *tbl, Eterm key, Eterm *ret)
while(b != 0) {
if (has_live_key(tb,b,key,hval)) {
--nitems_diff;
- if (nitems_diff == -1 && IS_FIXED(tb)) {
+ if (nitems_diff == -1 && IS_FIXED(tb)
+ && add_fixed_deletion(tb, ix, 0)) {
/* Pseudo remove (no need to keep several of same key) */
- add_fixed_deletion(tb, ix);
b->hvalue = INVALID_HASH;
} else {
*bp = b->next;
@@ -1196,9 +1202,8 @@ static int db_erase_object_hash(DbTable *tbl, Eterm object, Eterm *ret)
++nkeys;
if (db_eq(&tb->common,object, &b->dbterm)) {
--nitems_diff;
- if (nkeys==1 && IS_FIXED(tb)) { /* Pseudo remove */
- add_fixed_deletion(tb,ix);
- b->hvalue = INVALID_HASH;
+ if (nkeys==1 && IS_FIXED(tb) && add_fixed_deletion(tb,ix,0)) {
+ b->hvalue = INVALID_HASH; /* Pseudo remove */
bp = &b->next;
b = b->next;
} else {
@@ -1820,14 +1825,17 @@ static int db_select_delete_hash(Process *p,
int did_erase = 0;
if (db_match_dbterm(&tb->common, p, mpi.mp, 0,
&(*current)->dbterm, NULL, 0) == am_true) {
+ HashDbTerm *del;
if (NFIXED(tb) > fixated_by_me) { /* fixated by others? */
if (slot_ix != last_pseudo_delete) {
- add_fixed_deletion(tb, slot_ix);
- last_pseudo_delete = slot_ix;
+ if (!add_fixed_deletion(tb, slot_ix, fixated_by_me))
+ goto do_erase;
+ last_pseudo_delete = slot_ix;
}
(*current)->hvalue = INVALID_HASH;
} else {
- HashDbTerm *del = *current;
+ do_erase:
+ del = *current;
*current = (*current)->next;
free_term(tb, del);
did_erase = 1;
@@ -1931,14 +1939,17 @@ static int db_select_delete_continue_hash(Process *p,
int did_erase = 0;
if (db_match_dbterm(&tb->common, p, mp, 0,
&(*current)->dbterm, NULL, 0) == am_true) {
+ HashDbTerm *del;
if (NFIXED(tb) > fixated_by_me) { /* fixated by others? */
if (slot_ix != last_pseudo_delete) {
- add_fixed_deletion(tb, slot_ix);
+ if (!add_fixed_deletion(tb, slot_ix, fixated_by_me))
+ goto do_erase;
last_pseudo_delete = slot_ix;
}
(*current)->hvalue = INVALID_HASH;
} else {
- HashDbTerm *del = *current;
+ do_erase:
+ del = *current;
*current = (*current)->next;
free_term(tb, del);
did_erase = 1;
@@ -2089,9 +2100,9 @@ static int db_take_hash(Process *p, DbTable *tbl, Eterm key, Eterm *ret)
*ret = get_term_list(p, tb, key, hval, b, &bend);
while (b != bend) {
--nitems_diff;
- if (nitems_diff == -1 && IS_FIXED(tb)) {
+ if (nitems_diff == -1 && IS_FIXED(tb)
+ && add_fixed_deletion(tb, ix, 0)) {
/* Pseudo remove (no need to keep several of same key) */
- add_fixed_deletion(tb, ix);
bp = &b->next;
b->hvalue = INVALID_HASH;
b = b->next;
@@ -2131,7 +2142,7 @@ int db_mark_all_deleted_hash(DbTable *tbl)
for (i = 0; i < NACTIVE(tb); i++) {
if ((list = BUCKET(tb,i)) != NULL) {
- add_fixed_deletion(tb, i);
+ add_fixed_deletion(tb, i, 0);
do {
list->hvalue = INVALID_HASH;
list = list->next;
@@ -2190,11 +2201,11 @@ static void db_print_hash(int to, void *to_arg, int show, DbTable *tbl)
erts_print(to, to_arg, "*");
if (tb->common.compress) {
Eterm key = GETKEY(tb, list->dbterm.tpl);
- erts_print(to, to_arg, "key=%R", key, list->dbterm.tpl);
+ erts_print(to, to_arg, "key=%T", key);
}
else {
- Eterm obj = make_tuple_rel(list->dbterm.tpl,list->dbterm.tpl);
- erts_print(to, to_arg, "%R", obj, list->dbterm.tpl);
+ Eterm obj = make_tuple(list->dbterm.tpl);
+ erts_print(to, to_arg, "%T", obj);
}
if (list->next != 0)
erts_print(to, to_arg, ",");
@@ -2885,9 +2896,6 @@ Ldone:
handle->dbterm = &b->dbterm;
handle->flags = flags;
handle->new_size = b->dbterm.size;
-#if HALFWORD_HEAP
- handle->abs_vec = NULL;
-#endif
handle->lck = lck;
return 1;
}
@@ -2908,8 +2916,8 @@ db_finalize_dbterm_hash(int cret, DbUpdateHandle* handle)
ASSERT((&b->dbterm == handle->dbterm) == !(tb->common.compress && handle->flags & DB_MUST_RESIZE));
if (handle->flags & DB_NEW_OBJECT && cret != DB_ERROR_NONE) {
- if (IS_FIXED(tb)) {
- add_fixed_deletion(tb, hash_to_ix(tb, b->hvalue));
+ if (IS_FIXED(tb) && add_fixed_deletion(tb, hash_to_ix(tb, b->hvalue),
+ 0)) {
b->hvalue = INVALID_HASH;
} else {
*bp = b->next;