[src/trunk]: src/sys/net - Make _NET_STAT_GETREF()'s return value a net_stat_...

[thorpej <thorpej%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/075daa990006
branches:  trunk
changeset: 1006830:075daa990006
user:      thorpej <thorpej%NetBSD.org@localhost>
date:      Wed Jan 29 03:04:55 2020 +0000

description:
- Make _NET_STAT_GETREF()'s return value a net_stat_ref_t, which is
  defined as a "void *" to prevent using a net_stat_ref_t as an array.
- For each _NET_STATADD(), etc. macro, also define a _NET_STATADD_REF()
  macro that takes a ref returned by _NET_STAT_GETREF() as an argument.
  This is intended to replace direct subscripting of the refernce;
  consumers of this API will be updated in future commits.

diffstat:

 sys/net/net_stats.h |  48 +++++++++++++++++++++++++++++++++++++-----------
 1 files changed, 37 insertions(+), 11 deletions(-)

diffs (83 lines):

diff -r 79a1ca58ab12 -r 075daa990006 sys/net/net_stats.h
--- a/sys/net/net_stats.h       Wed Jan 29 02:58:51 2020 +0000
+++ b/sys/net/net_stats.h       Wed Jan 29 03:04:55 2020 +0000
@@ -1,7 +1,7 @@
-/*     $NetBSD: net_stats.h,v 1.4 2014/09/05 06:01:24 matt Exp $       */
+/*     $NetBSD: net_stats.h,v 1.5 2020/01/29 03:04:55 thorpej Exp $    */
 
 /*-
- * Copyright (c) 2008 The NetBSD Foundation, Inc.
+ * Copyright (c) 2008, 2020 The NetBSD Foundation, Inc.
  * All rights reserved.
  *
  * This code is derived from software contributed to The NetBSD Foundation
@@ -35,34 +35,60 @@
 #ifdef _KERNEL
 #include <sys/percpu.h>
 
-#define        _NET_STAT_GETREF(stat)  ((uint64_t *)percpu_getref((stat)))
+typedef void *net_stat_ref_t;
+
+#define        _NET_STAT_GETREF(stat)  ((net_stat_ref_t)percpu_getref((stat)))
 #define        _NET_STAT_PUTREF(stat)  percpu_putref((stat))
 
+#define        _NET_STATINC_REF(r, x)                                          \
+do {                                                                   \
+       uint64_t *_stat_ = (r);                                         \
+       _stat_[x]++;                                                    \
+} while (/*CONSTCOND*/0)
+
 #define        _NET_STATINC(stat, x)                                           \
 do {                                                                   \
-       uint64_t *_stat_ = _NET_STAT_GETREF(stat);                      \
-       _stat_[x]++;                                                    \
+       net_stat_ref_t _nsr_ = _NET_STAT_GETREF(stat);                  \
+       _NET_STATINC_REF(_nsr_, x);                                     \
        _NET_STAT_PUTREF(stat);                                         \
 } while (/*CONSTCOND*/0)
 
+#define        _NET_STATDEC_REF(r, x)                                          \
+do {                                                                   \
+       uint64_t *_stat_ = (r);                                         \
+       _stat_[x]--;                                                    \
+} while (/*CONSTCOND*/0)
+
 #define        _NET_STATDEC(stat, x)                                           \
 do {                                                                   \
-       uint64_t *_stat_ = _NET_STAT_GETREF(stat);                      \
-       _stat_[x]--;                                                    \
+       net_stat_ref_t _nsr_ = _NET_STAT_GETREF(stat);                  \
+       _NET_STATDEC_REF(_nsr_, x);                                     \
        _NET_STAT_PUTREF(stat);                                         \
 } while (/*CONSTCOND*/0)
 
+#define        _NET_STATADD_REF(r, x, v)                                       \
+do {                                                                   \
+       uint64_t *_stat_ = (r);                                         \
+       _stat_[x] += (v);                                               \
+} while (/*CONSTCOND*/0)
+
 #define        _NET_STATADD(stat, x, v)                                        \
 do {                                                                   \
-       uint64_t *_stat_ = _NET_STAT_GETREF(stat);                      \
-       _stat_[x] += (v);                                               \
+       net_stat_ref_t _nsr_ = _NET_STAT_GETREF(stat);                  \
+       _NET_STATADD_REF(_nsr_, x, v);                                  \
        _NET_STAT_PUTREF(stat);                                         \
 } while (/*CONSTCOND*/0)
 
+#define        _NET_STATSUB_REF(r, x, v)                                       \
+do {                                                                   \
+       uint64_t *_stat_ = (r);                                         \
+       _stat_[x] -= (v);                                               \
+} while (/*CONSTCOND*/0)
+
 #define        _NET_STATSUB(stat, x, v)                                        \
 do {                                                                   \
-       uint64_t *_stat_ = _NET_STAT_GETREF(stat);                      \
-       _stat_[x] -= (v);                                               \
+       net_stat_ref_t _nsr_ = _NET_STAT_GETREF(stat);                  \
+       _NET_STATSUB_REF(_nsr_, x, v);                                  \
        _NET_STAT_PUTREF(stat);                                         \
 } while (/*CONSTCOND*/0)