Add description for uma_zcreate().

Submitted by:	arr

share/man/man9/Makefile

@@ -391,6 +391,7 @@ MLINKS+=vcount.9 count_dev.9
 
 MLINKS+=zone.9 uma.9
 MLINKS+=zone.9 uma_zalloc.9
+MLINKS+=zone.9 uma_zcreate.9
 MLINKS+=zone.9 uma_zfree.9
 MLINKS+=zone.9 uma_zdestroy.9
 

share/man/man9/zone.9

@@ -29,6 +29,7 @@
 .Dt ZONE 9
 .Os
 .Sh NAME
+.Nm uma_zcreate ,
 .Nm uma_zalloc ,
 .Nm uma_zfree ,
 .Nm uma_zdestroy
@@ -37,6 +38,9 @@
 .In sys/param.h
 .In sys/queue.h
 .In vm/uma.h
+.Ft uma_zone_t
+.Fn uma_zcreate "char *name" "int size" "uma_ctor ctor" "uma_dtor dtor" "uma_in
+it uminit" "uma_fini fini" "int align" "u_int16_t flags"
 .Ft void *
 .Fn uma_zalloc "uma_zone_t zone, int flags"
 .Ft void
@@ -77,6 +81,14 @@ it will have been cleared to zeroes, however subsequent allocations
 will retain the contents as of the last free, with the exception of the
 fields mentioned above.
 .Pp
+The
+.Fn uma_zcreate
+function creates a new zone from which items may then be allocated from.
+The
+.Fa name
+argument is a text name of the zone for debugging and stats; this memory
+should not be freed until the zone has been deallocated.
+.Pp
 To allocate an item from a zone, simply call
 .Fn uma_zalloc
 with a pointer to that zone