diff options
Diffstat (limited to 'usr/src/lib/libumem/common/umem.c')
| -rw-r--r-- | usr/src/lib/libumem/common/umem.c | 28 |
1 files changed, 27 insertions, 1 deletions
diff --git a/usr/src/lib/libumem/common/umem.c b/usr/src/lib/libumem/common/umem.c index 725d4add40..6f2304390f 100644 --- a/usr/src/lib/libumem/common/umem.c +++ b/usr/src/lib/libumem/common/umem.c @@ -20,7 +20,7 @@ * CDDL HEADER END */ /* - * Copyright 2004 Sun Microsystems, Inc. All rights reserved. + * Copyright 2005 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ @@ -55,6 +55,7 @@ * * * KM_SLEEP v.s. UMEM_NOFAIL * + * * lock ordering * * 2. Initialization * ----------------- @@ -329,6 +330,31 @@ * If a constructor callback _does_ do a UMEM_NOFAIL allocation, and * the nofail callback does a non-local exit, we will leak the * partially-constructed buffer. + * + * + * 6. Lock Ordering + * ---------------- + * umem has a few more locks than kmem does, mostly in the update path. The + * overall lock ordering (earlier locks must be acquired first) is: + * + * umem_init_lock + * + * vmem_list_lock + * vmem_nosleep_lock.vmpl_mutex + * vmem_t's: + * vm_lock + * sbrk_faillock + * + * umem_cache_lock + * umem_update_lock + * umem_flags_lock + * umem_cache_t's: + * cache_cpu[*].cc_lock + * cache_depot_lock + * cache_lock + * umem_log_header_t's: + * lh_cpu[*].clh_lock + * lh_lock */ #include "mtlib.h" |