Expose real size of UMA allocations via libmemstat(3).

Sponsored by:	Nginx, Inc.

5 files changed, 19 insertions, 1 deletions

diff --git a/lib/libmemstat/libmemstat.3 b/lib/libmemstat/libmemstat.3
index 9b749f0..3eff156 100644
--- a/lib/libmemstat/libmemstat.3
+++ b/lib/libmemstat/libmemstat.3
@@ -24,7 +24,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd February 25, 2012
+.Dd February 11, 2014
 .Dt LIBMEMSTAT 3
 .Os
 .Sh NAME
@@ -80,6 +80,8 @@
 .Ft uint64_t
 .Fn memstat_get_size "const struct memory_type *mtp"
 .Ft uint64_t
+.Fn memstat_get_rsize "const struct memory_type *mtp"
+.Ft uint64_t
 .Fn memstat_get_memalloced "const struct memory_type *mtp"
 .Ft uint64_t
 .Fn memstat_get_memfreed "const struct memory_type *mtp"
@@ -287,6 +289,11 @@ If the memory type supports variable allocation sizes, return a bitmask of
 sizes allocated for the memory type.
 .It Fn memstat_get_size
 If the memory type supports a fixed allocation size, return that size.
+.It Fn memstat_get_rsize
+If the memory type supports a fixed allocation size, return real size
+of an allocation.
+Real size can exceed requested size due to alignment constraints or
+implicit padding.
 .It Fn memstat_get_memalloced
 Return the total number of bytes allocated for the memory type over its
 lifetime.
diff --git a/lib/libmemstat/memstat.c b/lib/libmemstat/memstat.c
index c7957c8..40bdc9d 100644
--- a/lib/libmemstat/memstat.c
+++ b/lib/libmemstat/memstat.c
@@ -254,6 +254,13 @@ memstat_get_size(const struct memory_type *mtp)
 }
 
 uint64_t
+memstat_get_rsize(const struct memory_type *mtp)
+{
+
+	return (mtp->mt_rsize);
+}
+
+uint64_t
 memstat_get_memalloced(const struct memory_type *mtp)
 {
 
diff --git a/lib/libmemstat/memstat.h b/lib/libmemstat/memstat.h
index cca75b3..8394dc1 100644
--- a/lib/libmemstat/memstat.h
+++ b/lib/libmemstat/memstat.h
@@ -124,6 +124,7 @@ uint64_t	 memstat_get_countlimit(const struct memory_type *mtp);
 uint64_t	 memstat_get_byteslimit(const struct memory_type *mtp);
 uint64_t	 memstat_get_sizemask(const struct memory_type *mtp);
 uint64_t	 memstat_get_size(const struct memory_type *mtp);
+uint64_t	 memstat_get_rsize(const struct memory_type *mtp);
 uint64_t	 memstat_get_memalloced(const struct memory_type *mtp);
 uint64_t	 memstat_get_memfreed(const struct memory_type *mtp);
 uint64_t	 memstat_get_numallocs(const struct memory_type *mtp);
diff --git a/lib/libmemstat/memstat_internal.h b/lib/libmemstat/memstat_internal.h
index 2416e09..9fdc228 100644
--- a/lib/libmemstat/memstat_internal.h
+++ b/lib/libmemstat/memstat_internal.h
@@ -51,6 +51,7 @@ struct memory_type {
 	uint64_t	 mt_byteslimit;	/* 0, or maximum bytes. */
 	uint64_t	 mt_sizemask;	/* malloc: allocated size bitmask. */
 	uint64_t	 mt_size;	/* uma: size of objects. */
+	uint64_t	 mt_rsize;	/* uma: real size of objects. */
 
 	/*
 	 * Zone or type information that includes all caches and any central
diff --git a/lib/libmemstat/memstat_uma.c b/lib/libmemstat/memstat_uma.c
index b8ff3a1..8e89585 100644
--- a/lib/libmemstat/memstat_uma.c
+++ b/lib/libmemstat/memstat_uma.c
@@ -212,6 +212,7 @@ retry:
 		}
 
 		mtp->mt_size = uthp->uth_size;
+		mtp->mt_rsize = uthp->uth_rsize;
 		mtp->mt_memalloced = mtp->mt_numallocs * uthp->uth_size;
 		mtp->mt_memfreed = mtp->mt_numfrees * uthp->uth_size;
 		mtp->mt_bytes = mtp->mt_memalloced - mtp->mt_memfreed;
@@ -435,6 +436,7 @@ memstat_kvm_uma(struct memory_type_list *list, void *kvm_handle)
 			}
 skip_percpu:
 			mtp->mt_size = kz.uk_size;
+			mtp->mt_rsize = kz.uk_rsize;
 			mtp->mt_memalloced = mtp->mt_numallocs * mtp->mt_size;
 			mtp->mt_memfreed = mtp->mt_numfrees * mtp->mt_size;
 			mtp->mt_bytes = mtp->mt_memalloced - mtp->mt_memfreed;