- Add a new UMA API: uma_zcache_create(). This makes a zone without any

   backing memory that is only a container for per-cpu caches of arbitrary
   pointer items.  These zones have no kegs.
 - Convert the regular keg based allocator to use the new import/release
   functions.
 - Move some stats to be atomics since they would require excessive zone
   locking/unlocking with the new import/release paradigm.  Make
   zone_free_item simpler now that callers can manage more stats.
 - Check for these cache-only zones in the public APIs and debugging
   code by checking zone_first_keg() against NULL.

Sponsored by:	EMC / Isilong Storage Division

1 files changed, 23 insertions, 0 deletions

diff --git a/sys/vm/uma.h b/sys/vm/uma.h
index c26bcc8..c85f50d 100644
--- a/sys/vm/uma.h
+++ b/sys/vm/uma.h
@@ -124,6 +124,16 @@ typedef int (*uma_init)(void *mem, int size, int flags);
 typedef void (*uma_fini)(void *mem, int size);
 
 /*
+ * Import new memory into a cache zone.
+ */
+typedef int (*uma_import)(void *arg, void **store, int count, int flags);
+
+/*
+ * Free memory from a cache zone.
+ */
+typedef void (*uma_release)(void *arg, void **store, int count);
+
+/*
  * What's the difference between initializing and constructing?
  *
  * The item is initialized when it is cached, and this is the state that the
@@ -216,6 +226,19 @@ uma_zone_t uma_zsecond_create(char *name, uma_ctor ctor, uma_dtor dtor,
 int uma_zsecond_add(uma_zone_t zone, uma_zone_t master);
 
 /*
+ * Create cache-only zones.
+ *
+ * This allows uma's per-cpu cache facilities to handle arbitrary
+ * pointers.  Consumers must specify the import and release functions to
+ * fill and destroy caches.  UMA does not allocate any memory for these
+ * zones.  The 'arg' parameter is passed to import/release and is caller
+ * specific.
+ */
+uma_zone_t uma_zcache_create(char *name, uma_ctor ctor, uma_dtor dtor,
+		    uma_init zinit, uma_fini zfini, uma_import zimport,
+		    uma_release zrelease, void *arg, int flags);
+
+/*
  * Definitions for uma_zcreate flags
  *
  * These flags share space with UMA_ZFLAGs in uma_int.h.  Be careful not to