From: mpi <mpi@openbsd.org>
Date: Sat, 16 Sep 2023 09:33:27 +0000 (+0000)
Subject: Allow counters_read(9) to take an optional scratch buffer.
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=bf0d449c49808ab2d0a67677895f728770d3c8af;p=openbsd

Allow counters_read(9) to take an optional scratch buffer.

Using a scratch buffer makes it possible to take a consistent snapshot of
per-CPU counters without having to allocate memory.

Makes ddb(4) show uvmexp command work in OOM situations.

ok kn@, mvs@, cheloha@
---

diff --git a/share/man/man9/counters_alloc.9 b/share/man/man9/counters_alloc.9
index 1de8bffc639..01d343d356c 100644
--- a/share/man/man9/counters_alloc.9
+++ b/share/man/man9/counters_alloc.9
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: counters_alloc.9,v 1.12 2022/02/20 23:11:01 dlg Exp $
+.\"	$OpenBSD: counters_alloc.9,v 1.13 2023/09/16 09:33:28 mpi Exp $
 .\"
 .\" Copyright (c) 2016 David Gwynne <dlg@openbsd.org>
 .\"
@@ -14,7 +14,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: February 20 2022 $
+.Dd $Mdocdate: September 16 2023 $
 .Dt COUNTERS_ALLOC 9
 .Os
 .Sh NAME
@@ -64,6 +64,7 @@
 .Fa "struct cpumem *cm"
 .Fa "uint64_t *counters"
 .Fa "unsigned int ncounters"
+.Fa "uint64_t *scratch"
 .Fc
 .Ft void
 .Fn counters_zero "struct cpumem *cm" "unsigned int ncounters"
@@ -191,6 +192,12 @@ The sum of the counters is written to the
 array.
 The number of counters is specified with
 .Fa ncounters .
+.Fa scratch
+may point to a buffer used to temporarily hold
+.Fa counters .
+If
+.Dv NULL ,
+one will be dynamically allocated and freed.
 .Pp
 .Fn counters_zero
 iterates over each CPU's set of counters referenced by
diff --git a/sys/kern/kern_sysctl.c b/sys/kern/kern_sysctl.c
index 10c6b5acad8..07d9a6f9e80 100644
--- a/sys/kern/kern_sysctl.c
+++ b/sys/kern/kern_sysctl.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_sysctl.c,v 1.418 2023/07/16 03:01:31 yasuoka Exp $	*/
+/*	$OpenBSD: kern_sysctl.c,v 1.419 2023/09/16 09:33:27 mpi Exp $	*/
 /*	$NetBSD: kern_sysctl.c,v 1.17 1996/05/20 17:49:05 mrg Exp $	*/
 
 /*-
@@ -519,7 +519,7 @@ kern_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp,
 		unsigned int i;
 
 		memset(&mbs, 0, sizeof(mbs));
-		counters_read(mbstat, counters, MBSTAT_COUNT);
+		counters_read(mbstat, counters, MBSTAT_COUNT, NULL);
 		for (i = 0; i < MBSTAT_TYPES; i++)
 			mbs.m_mtypes[i] = counters[i];
 
diff --git a/sys/kern/subr_evcount.c b/sys/kern/subr_evcount.c
index c77c953630d..a1ed2ee7c3b 100644
--- a/sys/kern/subr_evcount.c
+++ b/sys/kern/subr_evcount.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: subr_evcount.c,v 1.15 2022/12/05 08:58:49 visa Exp $ */
+/*	$OpenBSD: subr_evcount.c,v 1.16 2023/09/16 09:33:27 mpi Exp $ */
 /*
  * Copyright (c) 2004 Artur Grabowski <art@openbsd.org>
  * Copyright (c) 2004 Aaron Campbell <aaron@openbsd.org>
@@ -101,7 +101,7 @@ evcount_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp,
 {
 	int error = 0, s, nintr, i;
 	struct evcount *ec;
-	u_int64_t count;
+	uint64_t count, scratch;
 
 	if (newp != NULL)
 		return (EPERM);
@@ -129,7 +129,7 @@ evcount_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp,
 		if (ec == NULL)
 			return (ENOENT);
 		if (ec->ec_percpu != NULL) {
-			counters_read(ec->ec_percpu, &count, 1);
+			counters_read(ec->ec_percpu, &count, 1, &scratch);
 		} else {
 			s = splhigh();
 			count = ec->ec_count;
diff --git a/sys/kern/subr_percpu.c b/sys/kern/subr_percpu.c
index 4cc66d0b81e..6c03becf49e 100644
--- a/sys/kern/subr_percpu.c
+++ b/sys/kern/subr_percpu.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: subr_percpu.c,v 1.10 2022/10/03 14:10:53 bluhm Exp $ */
+/*	$OpenBSD: subr_percpu.c,v 1.11 2023/09/16 09:33:27 mpi Exp $ */
 
 /*
  * Copyright (c) 2016 David Gwynne <dlg@openbsd.org>
@@ -159,17 +159,19 @@ counters_free(struct cpumem *cm, unsigned int n)
 }
 
 void
-counters_read(struct cpumem *cm, uint64_t *output, unsigned int n)
+counters_read(struct cpumem *cm, uint64_t *output, unsigned int n,
+    uint64_t *scratch)
 {
 	struct cpumem_iter cmi;
-	uint64_t *gen, *counters, *temp;
+	uint64_t *gen, *counters, *temp = scratch;
 	uint64_t enter, leave;
 	unsigned int i;
 
 	for (i = 0; i < n; i++)
 		output[i] = 0;
 
-	temp = mallocarray(n, sizeof(uint64_t), M_TEMP, M_WAITOK);
+	if (scratch == NULL)
+		temp = mallocarray(n, sizeof(uint64_t), M_TEMP, M_WAITOK);
 
 	gen = cpumem_first(&cmi, cm);
 	do {
@@ -202,7 +204,8 @@ counters_read(struct cpumem *cm, uint64_t *output, unsigned int n)
 		gen = cpumem_next(&cmi, cm);
 	} while (gen != NULL);
 
-	free(temp, M_TEMP, n * sizeof(uint64_t));
+	if (scratch == NULL)
+		free(temp, M_TEMP, n * sizeof(uint64_t));
 }
 
 void
@@ -305,7 +308,8 @@ counters_free(struct cpumem *cm, unsigned int n)
 }
 
 void
-counters_read(struct cpumem *cm, uint64_t *output, unsigned int n)
+counters_read(struct cpumem *cm, uint64_t *output, unsigned int n,
+    uint64_t *scratch)
 {
 	uint64_t *counters;
 	unsigned int i;
diff --git a/sys/net/if.c b/sys/net/if.c
index 7f60292fdb1..94ebb42744a 100644
--- a/sys/net/if.c
+++ b/sys/net/if.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if.c,v 1.707 2023/08/18 08:10:16 jsg Exp $	*/
+/*	$OpenBSD: if.c,v 1.708 2023/09/16 09:33:27 mpi Exp $	*/
 /*	$NetBSD: if.c,v 1.35 1996/05/07 05:26:04 thorpej Exp $	*/
 
 /*
@@ -2797,7 +2797,8 @@ if_getdata(struct ifnet *ifp, struct if_data *data)
 	if (ifp->if_counters != NULL) {
 		uint64_t counters[ifc_ncounters];
 
-		counters_read(ifp->if_counters, counters, nitems(counters));
+		counters_read(ifp->if_counters, counters, nitems(counters),
+		    NULL);
 
 		data->ifi_ipackets += counters[ifc_ipackets];
 		data->ifi_ierrors += counters[ifc_ierrors];
diff --git a/sys/net/if_etherip.c b/sys/net/if_etherip.c
index 3abc9d4b5aa..4abd3f167e4 100644
--- a/sys/net/if_etherip.c
+++ b/sys/net/if_etherip.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_etherip.c,v 1.50 2022/02/28 00:12:11 dlg Exp $	*/
+/*	$OpenBSD: if_etherip.c,v 1.51 2023/09/16 09:33:27 mpi Exp $	*/
 /*
  * Copyright (c) 2015 Kazuya GODA <goda@openbsd.org>
  *
@@ -789,7 +789,7 @@ etherip_sysctl_etheripstat(void *oldp, size_t *oldlenp, void *newp)
 	    sizeof(uint64_t)));
 	memset(&etheripstat, 0, sizeof etheripstat);
 	counters_read(etheripcounters, (uint64_t *)&etheripstat,
-	    etherips_ncounters);
+	    etherips_ncounters, NULL);
 	return (sysctl_rdstruct(oldp, oldlenp, newp, &etheripstat,
 	    sizeof(etheripstat)));
 }
diff --git a/sys/net/if_pfsync.c b/sys/net/if_pfsync.c
index d57a0250210..0a067bc547f 100644
--- a/sys/net/if_pfsync.c
+++ b/sys/net/if_pfsync.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_pfsync.c,v 1.320 2023/08/18 08:03:57 jsg Exp $	*/
+/*	$OpenBSD: if_pfsync.c,v 1.321 2023/09/16 09:33:27 mpi Exp $	*/
 
 /*
  * Copyright (c) 2002 Michael Shalayeff
@@ -3339,7 +3339,7 @@ pfsync_sysctl_pfsyncstat(void *oldp, size_t *oldlenp, void *newp)
 	CTASSERT(sizeof(pfsyncstat) == (pfsyncs_ncounters * sizeof(uint64_t)));
 	memset(&pfsyncstat, 0, sizeof pfsyncstat);
 	counters_read(pfsynccounters, (uint64_t *)&pfsyncstat,
-	    pfsyncs_ncounters);
+	    pfsyncs_ncounters, NULL);
 	return (sysctl_rdstruct(oldp, oldlenp, newp,
 	    &pfsyncstat, sizeof(pfsyncstat)));
 }
diff --git a/sys/net/pfkeyv2_convert.c b/sys/net/pfkeyv2_convert.c
index 68686055a11..83a1feb614e 100644
--- a/sys/net/pfkeyv2_convert.c
+++ b/sys/net/pfkeyv2_convert.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: pfkeyv2_convert.c,v 1.80 2023/08/07 03:35:06 dlg Exp $	*/
+/*	$OpenBSD: pfkeyv2_convert.c,v 1.81 2023/09/16 09:33:27 mpi Exp $	*/
 /*
  * The author of this code is Angelos D. Keromytis (angelos@keromytis.org)
  *
@@ -992,7 +992,7 @@ export_counter(void **p, struct tdb *tdb)
 	uint64_t counters[tdb_ncounters];
 	struct sadb_x_counter *scnt = (struct sadb_x_counter *)*p;
 
-	counters_read(tdb->tdb_counters, counters, tdb_ncounters);
+	counters_read(tdb->tdb_counters, counters, tdb_ncounters, NULL);
 
 	scnt->sadb_x_counter_len = sizeof(struct sadb_x_counter) /
 	    sizeof(uint64_t);
diff --git a/sys/net/pipex.c b/sys/net/pipex.c
index 3a1a524c669..71bd7bbec25 100644
--- a/sys/net/pipex.c
+++ b/sys/net/pipex.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: pipex.c,v 1.148 2022/08/30 19:42:29 bluhm Exp $ */
+/*	$OpenBSD: pipex.c,v 1.149 2023/09/16 09:33:27 mpi Exp $ */
 
 /*-
  * Copyright (c) 2009 Internet Initiative Japan Inc.
@@ -558,7 +558,7 @@ pipex_export_session_stats(struct pipex_session *session,
 
 	memset(stats, 0, sizeof(*stats));
 
-	counters_read(session->stat_counters, counters, pxc_ncounters);
+	counters_read(session->stat_counters, counters, pxc_ncounters, NULL);
 	stats->ipackets = counters[pxc_ipackets];
 	stats->ierrors = counters[pxc_ierrors];
 	stats->ibytes = counters[pxc_ibytes];
diff --git a/sys/net/rtsock.c b/sys/net/rtsock.c
index d7c5763df5b..d7b6d1907a3 100644
--- a/sys/net/rtsock.c
+++ b/sys/net/rtsock.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rtsock.c,v 1.369 2023/07/28 09:33:16 mvs Exp $	*/
+/*	$OpenBSD: rtsock.c,v 1.370 2023/09/16 09:33:27 mpi Exp $	*/
 /*	$NetBSD: rtsock.c,v 1.18 1996/03/29 00:32:10 cgd Exp $	*/
 
 /*
@@ -2245,7 +2245,7 @@ sysctl_rtable_rtstat(void *oldp, size_t *oldlenp, void *newp)
 
 	CTASSERT(sizeof(rtstat) == (nitems(counters) * sizeof(uint32_t)));
 	memset(&rtstat, 0, sizeof rtstat);
-	counters_read(rtcounters, counters, nitems(counters));
+	counters_read(rtcounters, counters, nitems(counters), NULL);
 
 	for (i = 0; i < nitems(counters); i++)
 		words[i] = (uint32_t)counters[i];
diff --git a/sys/netinet/igmp.c b/sys/netinet/igmp.c
index 82b6cb5d090..00dba7d2088 100644
--- a/sys/netinet/igmp.c
+++ b/sys/netinet/igmp.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: igmp.c,v 1.82 2022/09/08 10:22:06 kn Exp $	*/
+/*	$OpenBSD: igmp.c,v 1.83 2023/09/16 09:33:27 mpi Exp $	*/
 /*	$NetBSD: igmp.c,v 1.15 1996/02/13 23:41:25 christos Exp $	*/
 
 /*
@@ -687,7 +687,7 @@ igmp_sysctl_igmpstat(void *oldp, size_t *oldlenp, void *newp)
 
 	CTASSERT(sizeof(igmpstat) == (nitems(counters) * sizeof(u_long)));
 	memset(&igmpstat, 0, sizeof igmpstat);
-	counters_read(igmpcounters, counters, nitems(counters));
+	counters_read(igmpcounters, counters, nitems(counters), NULL);
 
 	for (i = 0; i < nitems(counters); i++)
 		words[i] = (u_long)counters[i];
diff --git a/sys/netinet/ip_carp.c b/sys/netinet/ip_carp.c
index 064c4424910..9aae24d5dde 100644
--- a/sys/netinet/ip_carp.c
+++ b/sys/netinet/ip_carp.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip_carp.c,v 1.357 2023/05/16 14:32:54 jan Exp $	*/
+/*	$OpenBSD: ip_carp.c,v 1.358 2023/09/16 09:33:27 mpi Exp $	*/
 
 /*
  * Copyright (c) 2002 Michael Shalayeff. All rights reserved.
@@ -749,7 +749,8 @@ carp_sysctl_carpstat(void *oldp, size_t *oldlenp, void *newp)
 
 	CTASSERT(sizeof(carpstat) == (carps_ncounters * sizeof(uint64_t)));
 	memset(&carpstat, 0, sizeof carpstat);
-	counters_read(carpcounters, (uint64_t *)&carpstat, carps_ncounters);
+	counters_read(carpcounters, (uint64_t *)&carpstat, carps_ncounters,
+	    NULL);
 	return (sysctl_rdstruct(oldp, oldlenp, newp,
 	    &carpstat, sizeof(carpstat)));
 }
diff --git a/sys/netinet/ip_divert.c b/sys/netinet/ip_divert.c
index acb00eb853c..b21569e7205 100644
--- a/sys/netinet/ip_divert.c
+++ b/sys/netinet/ip_divert.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: ip_divert.c,v 1.91 2023/05/13 13:35:17 bluhm Exp $ */
+/*      $OpenBSD: ip_divert.c,v 1.92 2023/09/16 09:33:27 mpi Exp $ */
 
 /*
  * Copyright (c) 2009 Michele Marchetto <michele@openbsd.org>
@@ -350,7 +350,7 @@ divert_sysctl_divstat(void *oldp, size_t *oldlenp, void *newp)
 
 	CTASSERT(sizeof(divstat) == (nitems(counters) * sizeof(u_long)));
 	memset(&divstat, 0, sizeof divstat);
-	counters_read(divcounters, counters, nitems(counters));
+	counters_read(divcounters, counters, nitems(counters), NULL);
 
 	for (i = 0; i < nitems(counters); i++)
 		words[i] = (u_long)counters[i];
diff --git a/sys/netinet/ip_icmp.c b/sys/netinet/ip_icmp.c
index 44811886c26..30bec63a512 100644
--- a/sys/netinet/ip_icmp.c
+++ b/sys/netinet/ip_icmp.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip_icmp.c,v 1.191 2022/05/05 13:57:40 claudio Exp $	*/
+/*	$OpenBSD: ip_icmp.c,v 1.192 2023/09/16 09:33:27 mpi Exp $	*/
 /*	$NetBSD: ip_icmp.c,v 1.19 1996/02/13 23:42:22 christos Exp $	*/
 
 /*
@@ -917,7 +917,7 @@ icmp_sysctl_icmpstat(void *oldp, size_t *oldlenp, void *newp)
 
 	CTASSERT(sizeof(icmpstat) == (nitems(counters) * sizeof(u_long)));
 	memset(&icmpstat, 0, sizeof icmpstat);
-	counters_read(icmpcounters, counters, nitems(counters));
+	counters_read(icmpcounters, counters, nitems(counters), NULL);
 
 	for (i = 0; i < nitems(counters); i++)
 		words[i] = (u_long)counters[i];
diff --git a/sys/netinet/ip_input.c b/sys/netinet/ip_input.c
index 5db74552c14..279252353cc 100644
--- a/sys/netinet/ip_input.c
+++ b/sys/netinet/ip_input.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip_input.c,v 1.386 2023/09/06 11:09:43 bluhm Exp $	*/
+/*	$OpenBSD: ip_input.c,v 1.387 2023/09/16 09:33:27 mpi Exp $	*/
 /*	$NetBSD: ip_input.c,v 1.30 1996/03/16 23:53:58 christos Exp $	*/
 
 /*
@@ -1747,7 +1747,7 @@ ip_sysctl_ipstat(void *oldp, size_t *oldlenp, void *newp)
 
 	CTASSERT(sizeof(ipstat) == (nitems(counters) * sizeof(u_long)));
 	memset(&ipstat, 0, sizeof ipstat);
-	counters_read(ipcounters, counters, nitems(counters));
+	counters_read(ipcounters, counters, nitems(counters), NULL);
 
 	for (i = 0; i < nitems(counters); i++)
 		words[i] = (u_long)counters[i];
diff --git a/sys/netinet/ip_ipip.c b/sys/netinet/ip_ipip.c
index e9a561393ff..f56caca9841 100644
--- a/sys/netinet/ip_ipip.c
+++ b/sys/netinet/ip_ipip.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip_ipip.c,v 1.98 2022/01/02 22:36:04 jsg Exp $ */
+/*	$OpenBSD: ip_ipip.c,v 1.99 2023/09/16 09:33:27 mpi Exp $ */
 /*
  * The authors of this code are John Ioannidis (ji@tla.org),
  * Angelos D. Keromytis (kermit@csd.uch.gr) and
@@ -573,7 +573,8 @@ ipip_sysctl_ipipstat(void *oldp, size_t *oldlenp, void *newp)
 
 	CTASSERT(sizeof(ipipstat) == (ipips_ncounters * sizeof(uint64_t)));
 	memset(&ipipstat, 0, sizeof ipipstat);
-	counters_read(ipipcounters, (uint64_t *)&ipipstat, ipips_ncounters);
+	counters_read(ipipcounters, (uint64_t *)&ipipstat, ipips_ncounters,
+	    NULL);
 	return (sysctl_rdstruct(oldp, oldlenp, newp,
 	    &ipipstat, sizeof(ipipstat)));
 }
diff --git a/sys/netinet/ipsec_input.c b/sys/netinet/ipsec_input.c
index 9e3f4dee18f..07de8e38eff 100644
--- a/sys/netinet/ipsec_input.c
+++ b/sys/netinet/ipsec_input.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ipsec_input.c,v 1.205 2023/08/07 03:43:57 dlg Exp $	*/
+/*	$OpenBSD: ipsec_input.c,v 1.206 2023/09/16 09:33:27 mpi Exp $	*/
 /*
  * The authors of this code are John Ioannidis (ji@tla.org),
  * Angelos D. Keromytis (kermit@csd.uch.gr) and
@@ -664,7 +664,7 @@ esp_sysctl_espstat(void *oldp, size_t *oldlenp, void *newp)
 
 	CTASSERT(sizeof(espstat) == (esps_ncounters * sizeof(uint64_t)));
 	memset(&espstat, 0, sizeof espstat);
-	counters_read(espcounters, (uint64_t *)&espstat, esps_ncounters);
+	counters_read(espcounters, (uint64_t *)&espstat, esps_ncounters, NULL);
 	return (sysctl_rdstruct(oldp, oldlenp, newp, &espstat,
 	    sizeof(espstat)));
 }
@@ -698,7 +698,7 @@ ah_sysctl_ahstat(void *oldp, size_t *oldlenp, void *newp)
 
 	CTASSERT(sizeof(ahstat) == (ahs_ncounters * sizeof(uint64_t)));
 	memset(&ahstat, 0, sizeof ahstat);
-	counters_read(ahcounters, (uint64_t *)&ahstat, ahs_ncounters);
+	counters_read(ahcounters, (uint64_t *)&ahstat, ahs_ncounters, NULL);
 	return (sysctl_rdstruct(oldp, oldlenp, newp, &ahstat, sizeof(ahstat)));
 }
 
@@ -733,7 +733,7 @@ ipcomp_sysctl_ipcompstat(void *oldp, size_t *oldlenp, void *newp)
 	CTASSERT(sizeof(ipcompstat) == (ipcomps_ncounters * sizeof(uint64_t)));
 	memset(&ipcompstat, 0, sizeof ipcompstat);
 	counters_read(ipcompcounters, (uint64_t *)&ipcompstat,
-	    ipcomps_ncounters);
+	    ipcomps_ncounters, NULL);
 	return (sysctl_rdstruct(oldp, oldlenp, newp, &ipcompstat,
 	    sizeof(ipcompstat)));
 }
@@ -745,7 +745,8 @@ ipsec_sysctl_ipsecstat(void *oldp, size_t *oldlenp, void *newp)
 
 	CTASSERT(sizeof(ipsecstat) == (ipsec_ncounters * sizeof(uint64_t)));
 	memset(&ipsecstat, 0, sizeof ipsecstat);
-	counters_read(ipseccounters, (uint64_t *)&ipsecstat, ipsec_ncounters);
+	counters_read(ipseccounters, (uint64_t *)&ipsecstat, ipsec_ncounters,
+	    NULL);
 	return (sysctl_rdstruct(oldp, oldlenp, newp, &ipsecstat,
 	    sizeof(ipsecstat)));
 }
diff --git a/sys/netinet/tcp_usrreq.c b/sys/netinet/tcp_usrreq.c
index 75d69a12aa7..f96fc7782e5 100644
--- a/sys/netinet/tcp_usrreq.c
+++ b/sys/netinet/tcp_usrreq.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: tcp_usrreq.c,v 1.221 2023/07/06 09:15:24 bluhm Exp $	*/
+/*	$OpenBSD: tcp_usrreq.c,v 1.222 2023/09/16 09:33:27 mpi Exp $	*/
 /*	$NetBSD: tcp_usrreq.c,v 1.20 1996/02/13 23:44:16 christos Exp $	*/
 
 /*
@@ -1237,7 +1237,7 @@ tcp_sysctl_tcpstat(void *oldp, size_t *oldlenp, void *newp)
 #define ASSIGN(field)	do { tcpstat.field = counters[i++]; } while (0)
 
 	memset(&tcpstat, 0, sizeof tcpstat);
-	counters_read(tcpcounters, counters, nitems(counters));
+	counters_read(tcpcounters, counters, nitems(counters), NULL);
 	ASSIGN(tcps_connattempt);
 	ASSIGN(tcps_accepts);
 	ASSIGN(tcps_connects);
diff --git a/sys/netinet/udp_usrreq.c b/sys/netinet/udp_usrreq.c
index 89a18a98d1c..5daee4d8efb 100644
--- a/sys/netinet/udp_usrreq.c
+++ b/sys/netinet/udp_usrreq.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: udp_usrreq.c,v 1.305 2023/01/22 12:05:44 mvs Exp $	*/
+/*	$OpenBSD: udp_usrreq.c,v 1.306 2023/09/16 09:33:27 mpi Exp $	*/
 /*	$NetBSD: udp_usrreq.c,v 1.28 1996/03/16 23:54:03 christos Exp $	*/
 
 /*
@@ -1314,7 +1314,7 @@ udp_sysctl_udpstat(void *oldp, size_t *oldlenp, void *newp)
 
 	CTASSERT(sizeof(udpstat) == (nitems(counters) * sizeof(u_long)));
 	memset(&udpstat, 0, sizeof udpstat);
-	counters_read(udpcounters, counters, nitems(counters));
+	counters_read(udpcounters, counters, nitems(counters), NULL);
 
 	for (i = 0; i < nitems(counters); i++)
 		words[i] = (u_long)counters[i];
diff --git a/sys/netinet6/icmp6.c b/sys/netinet6/icmp6.c
index 9173b5292a1..868f3f5d755 100644
--- a/sys/netinet6/icmp6.c
+++ b/sys/netinet6/icmp6.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: icmp6.c,v 1.248 2023/04/05 21:51:47 bluhm Exp $	*/
+/*	$OpenBSD: icmp6.c,v 1.249 2023/09/16 09:33:27 mpi Exp $	*/
 /*	$KAME: icmp6.c,v 1.217 2001/06/20 15:03:29 jinmei Exp $	*/
 
 /*
@@ -1870,7 +1870,8 @@ icmp6_sysctl_icmp6stat(void *oldp, size_t *oldlenp, void *newp)
 
 	CTASSERT(sizeof(*icmp6stat) == icp6s_ncounters * sizeof(uint64_t));
 	icmp6stat = malloc(sizeof(*icmp6stat), M_TEMP, M_WAITOK|M_ZERO);
-	counters_read(icmp6counters, (uint64_t *)icmp6stat, icp6s_ncounters);
+	counters_read(icmp6counters, (uint64_t *)icmp6stat, icp6s_ncounters,
+	    NULL);
 	ret = sysctl_rdstruct(oldp, oldlenp, newp,
 	    icmp6stat, sizeof(*icmp6stat));
 	free(icmp6stat, M_TEMP, sizeof(*icmp6stat));
diff --git a/sys/netinet6/ip6_divert.c b/sys/netinet6/ip6_divert.c
index aa7fc4ccdcc..6826bd9a287 100644
--- a/sys/netinet6/ip6_divert.c
+++ b/sys/netinet6/ip6_divert.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: ip6_divert.c,v 1.89 2023/04/04 10:12:03 bluhm Exp $ */
+/*      $OpenBSD: ip6_divert.c,v 1.90 2023/09/16 09:33:27 mpi Exp $ */
 
 /*
  * Copyright (c) 2009 Michele Marchetto <michele@openbsd.org>
@@ -358,7 +358,7 @@ divert6_sysctl_div6stat(void *oldp, size_t *oldlenp, void *newp)
 
 	CTASSERT(sizeof(div6stat) == (nitems(counters) * sizeof(u_long)));
 
-	counters_read(div6counters, counters, nitems(counters));
+	counters_read(div6counters, counters, nitems(counters), NULL);
 
 	for (i = 0; i < nitems(counters); i++)
 		words[i] = (u_long)counters[i];
diff --git a/sys/netinet6/ip6_input.c b/sys/netinet6/ip6_input.c
index be7e0010fa1..76ff8cbfbbf 100644
--- a/sys/netinet6/ip6_input.c
+++ b/sys/netinet6/ip6_input.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip6_input.c,v 1.255 2023/09/06 11:09:43 bluhm Exp $	*/
+/*	$OpenBSD: ip6_input.c,v 1.256 2023/09/16 09:33:27 mpi Exp $	*/
 /*	$KAME: ip6_input.c,v 1.188 2001/03/29 05:34:31 itojun Exp $	*/
 
 /*
@@ -1466,7 +1466,7 @@ ip6_sysctl_ip6stat(void *oldp, size_t *oldlenp, void *newp)
 	CTASSERT(sizeof(*ip6stat) == (ip6s_ncounters * sizeof(uint64_t)));
 
 	ip6stat = malloc(sizeof(*ip6stat), M_TEMP, M_WAITOK);
-	counters_read(ip6counters, (uint64_t *)ip6stat, ip6s_ncounters);
+	counters_read(ip6counters, (uint64_t *)ip6stat, ip6s_ncounters, NULL);
 	ret = sysctl_rdstruct(oldp, oldlenp, newp,
 	    ip6stat, sizeof(*ip6stat));
 	free(ip6stat, M_TEMP, sizeof(*ip6stat));
diff --git a/sys/netinet6/raw_ip6.c b/sys/netinet6/raw_ip6.c
index 1ef501434ad..05879b42fad 100644
--- a/sys/netinet6/raw_ip6.c
+++ b/sys/netinet6/raw_ip6.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: raw_ip6.c,v 1.172 2023/01/22 12:05:44 mvs Exp $	*/
+/*	$OpenBSD: raw_ip6.c,v 1.173 2023/09/16 09:33:27 mpi Exp $	*/
 /*	$KAME: raw_ip6.c,v 1.69 2001/03/04 15:55:44 itojun Exp $	*/
 
 /*
@@ -784,7 +784,8 @@ rip6_sysctl_rip6stat(void *oldp, size_t *oldplen, void *newp)
 	struct rip6stat rip6stat;
 
 	CTASSERT(sizeof(rip6stat) == rip6s_ncounters * sizeof(uint64_t));
-	counters_read(rip6counters, (uint64_t *)&rip6stat, rip6s_ncounters);
+	counters_read(rip6counters, (uint64_t *)&rip6stat, rip6s_ncounters,
+	    NULL);
 
 	return (sysctl_rdstruct(oldp, oldplen, newp,
 	    &rip6stat, sizeof(rip6stat)));
diff --git a/sys/sys/percpu.h b/sys/sys/percpu.h
index 53a1a885239..5595b1abafe 100644
--- a/sys/sys/percpu.h
+++ b/sys/sys/percpu.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: percpu.h,v 1.8 2018/08/28 15:15:02 mpi Exp $ */
+/*	$OpenBSD: percpu.h,v 1.9 2023/09/16 09:33:27 mpi Exp $ */
 
 /*
  * Copyright (c) 2016 David Gwynne <dlg@openbsd.org>
@@ -113,7 +113,8 @@ static struct {								\
 struct cpumem	*counters_alloc(unsigned int);
 struct cpumem	*counters_alloc_ncpus(struct cpumem *, unsigned int);
 void		 counters_free(struct cpumem *, unsigned int);
-void		 counters_read(struct cpumem *, uint64_t *, unsigned int);
+void		 counters_read(struct cpumem *, uint64_t *, unsigned int,
+		     uint64_t *);
 void		 counters_zero(struct cpumem *, unsigned int);
 
 static inline uint64_t *
diff --git a/sys/uvm/uvm_meter.c b/sys/uvm/uvm_meter.c
index 25bc9126d9d..3289cdb854a 100644
--- a/sys/uvm/uvm_meter.c
+++ b/sys/uvm/uvm_meter.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_meter.c,v 1.49 2023/08/18 09:18:52 claudio Exp $	*/
+/*	$OpenBSD: uvm_meter.c,v 1.50 2023/09/16 09:33:27 mpi Exp $	*/
 /*	$NetBSD: uvm_meter.c,v 1.21 2001/07/14 06:36:03 matt Exp $	*/
 
 /*
@@ -249,11 +249,12 @@ uvm_total(struct vmtotal *totalp)
 void
 uvmexp_read(struct uvmexp *uexp)
 {
-		uint64_t counters[exp_ncounters];
+		uint64_t counters[exp_ncounters], scratch[exp_ncounters];
 
 		memcpy(uexp, &uvmexp, sizeof(*uexp));
 
-		counters_read(uvmexp_counters, counters, exp_ncounters);
+		counters_read(uvmexp_counters, counters, exp_ncounters,
+		    scratch);
 
 		/* stat counters */
 		uexp->faults = (int)counters[faults];