Add memstat_kvm_uma(), an implementation of a libmemstat(3) query routine

that knows how to extract UMA(9) allocator statistics from a core dump or
live memory image using kvm(3).  The caller is expected to provide the
necessary kvm_t handle, which is then used by libmemstat(3).

With these changes, it is trivially straight forward to re-introduce
vmstat -z support on core dumps, which was lost when UMA was introduced.

In the short term, this requires including vm/ include files that are not
intended for extra-kernel use, requiring in turn some ugliness.

1 files changed, 9 insertions, 0 deletions

diff --git a/lib/libmemstat/memstat.h b/lib/libmemstat/memstat.h
index f46640876caf..561f6eedbdde 100644
--- a/lib/libmemstat/memstat.h
+++ b/lib/libmemstat/memstat.h
@@ -72,6 +72,9 @@
 #define	MEMSTAT_ERROR_PERMISSION	3	/* Permission denied. */
 #define	MEMSTAT_ERROR_TOOMANYCPUS	4	/* Too many CPUs. */
 #define	MEMSTAT_ERROR_DATAERROR		5	/* Error in stat data. */
+#define	MEMSTAT_ERROR_KVM		6	/* See kvm_geterr() for err. */
+#define	MEMSTAT_ERROR_KVM_NOSYMBOL	7	/* Symbol not available. */
+#define	MEMSTAT_ERROR_KVM_SHORTREAD	8	/* Short kvm_read return. */
 
 /*
  * Forward declare struct memory_type, which holds per-type properties and
@@ -113,6 +116,12 @@ int	memstat_sysctl_malloc(struct memory_type_list *list, int flags);
 int	memstat_sysctl_uma(struct memory_type_list *list, int flags);
 
 /*
+ * Functions to retrieve data from a kernel core (or /dev/kmem).
+ */
+int	memstat_kvm_all(struct memory_type_list *list, void *kvm_handle);
+int	memstat_kvm_uma(struct memory_type_list *list, void *kvm_handle);
+
+/*
  * Accessor methods for struct memory_type.
  */
 const char	*memstat_get_name(const struct memory_type *mtp);