diff options
Diffstat (limited to 'malloc')
| -rw-r--r-- | malloc/arena.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/malloc/arena.c b/malloc/arena.c index d3cf4b9f1b..b1c9469ce0 100644 --- a/malloc/arena.c +++ b/malloc/arena.c @@ -828,7 +828,7 @@ arena_get2(mstate a_tsd, size_t size) { if (mp_.arena_max != 0) narenas_limit = mp_.arena_max; - else + else if (narenas > mp_.arena_test) { int n = __get_nprocs (); @@ -842,7 +842,14 @@ arena_get2(mstate a_tsd, size_t size) } repeat:; size_t n = narenas; - if (__builtin_expect (n <= mp_.arena_test || n < narenas_limit, 0)) + /* NB: the following depends on the fact that (size_t)0 - 1 is a + very large number and that the underflow is OK. If arena_max + is set the value of arena_test is irrelevant. If arena_test + is set but narenas is not yet larger or equal to arena_test + narenas_limit is 0. There is no possibility for narenas to + be too big for the test to always fail since there is not + enough address space to create that many arenas. */ + if (__builtin_expect (n <= narenas_limit - 1, 0)) { if (catomic_compare_and_exchange_bool_acq (&narenas, n + 1, n)) goto repeat; |