Replace manyinstances of VM_WAIT with blocking page allocation flags

similar to the kernel memory allocator.

This simplifies NUMA allocation because the domain will be known at wait
time and races between failure and sleeping are eliminated.  This also
reduces boilerplate code and simplifies callers.

A wait primitive is supplied for uma zones for similar reasons.  This
eliminates some non-specific VM_WAIT calls in favor of more explicit
sleeps that may be satisfied without new pages.

Reviewed by:	alc, kib, markj
Tested by:	pho
Sponsored by:	Netflix, Dell/EMC Isilon

1 files changed, 5 insertions, 0 deletions

diff --git a/sys/vm/uma.h b/sys/vm/uma.h
index 71027b898cff..3e758050a1ff 100644
--- a/sys/vm/uma.h
+++ b/sys/vm/uma.h
@@ -366,6 +366,11 @@ uma_zfree(uma_zone_t zone, void *item)
 }
 
 /*
+ * Wait until the specified zone can allocate an item.
+ */
+void uma_zwait(uma_zone_t zone);
+
+/*
  * XXX The rest of the prototypes in this header are h0h0 magic for the VM.
  * If you think you need to use it for a normal zone you're probably incorrect.
  */