diff options
Diffstat (limited to 'sys/kern/subr_hash.c')
-rw-r--r-- | sys/kern/subr_hash.c | 29 |
1 files changed, 25 insertions, 4 deletions
diff --git a/sys/kern/subr_hash.c b/sys/kern/subr_hash.c index 915f3f7..4d9249f 100644 --- a/sys/kern/subr_hash.c +++ b/sys/kern/subr_hash.c @@ -104,16 +104,21 @@ static const int primes[] = { 1, 13, 31, 61, 127, 251, 509, 761, 1021, 1531, #define NPRIMES nitems(primes) /* - * General routine to allocate a prime number sized hash table. + * General routine to allocate a prime number sized hash table with control of + * memory flags. */ void * -phashinit(int elements, struct malloc_type *type, u_long *nentries) +phashinit_flags(int elements, struct malloc_type *type, u_long *nentries, int flags) { long hashsize; LIST_HEAD(generic, generic) *hashtbl; - int i; + int i, m_flags; KASSERT(elements > 0, ("%s: bad elements", __func__)); + /* Exactly one of HASH_WAITOK and HASH_NOWAIT must be set. */ + KASSERT((flags & HASH_WAITOK) ^ (flags & HASH_NOWAIT), + ("Bad flags (0x%x) passed to phashinit_flags", flags)); + for (i = 1, hashsize = primes[1]; hashsize <= elements;) { i++; if (i == NPRIMES) @@ -121,9 +126,25 @@ phashinit(int elements, struct malloc_type *type, u_long *nentries) hashsize = primes[i]; } hashsize = primes[i - 1]; - hashtbl = malloc((u_long)hashsize * sizeof(*hashtbl), type, M_WAITOK); + + m_flags = (flags & HASH_NOWAIT) ? M_NOWAIT : M_WAITOK; + hashtbl = malloc((u_long)hashsize * sizeof(*hashtbl), type, m_flags); + if (hashtbl == NULL) + return (NULL); + for (i = 0; i < hashsize; i++) LIST_INIT(&hashtbl[i]); *nentries = hashsize; return (hashtbl); } + +/* + * Allocate and initialize a prime number sized hash table with default flag: + * may sleep. + */ +void * +phashinit(int elements, struct malloc_type *type, u_long *nentries) +{ + + return (phashinit_flags(elements, type, nentries, HASH_WAITOK)); +} |