On 11/09/23(Mon) 21:05, Martin Pieuchot wrote:
> On 06/09/23(Wed) 23:13, Alexander Bluhm wrote:
> > On Wed, Sep 06, 2023 at 12:23:33PM -0500, Scott Cheloha wrote:
> > > On Wed, Sep 06, 2023 at 01:04:19PM +0100, Martin Pieuchot wrote:
> > > > Debugging OOM is hard. UVM uses per-CPU counters and sadly
> > > > counters_read(9) needs to allocate memory. This is not acceptable in
> > > > ddb(4). As a result I cannot see the content of UVM counters in OOM
> > > > situations.
> > > >
> > > > Diff below introduces a *_static() variant of counters_read(9) that
> > > > takes a secondary buffer to avoid calling malloc(9). Is it fine? Do
> > > > you have a better idea? Should we make it the default or using the
> > > > stack might be a problem?
> > >
> > > Instead of adding a second interface I think we could get away with
> > > just extending counters_read(9) to take a scratch buffer as an optional
> > > fourth parameter:
> > >
> > > void
> > > counters_read(struct cpumem *cm, uint64_t *output, unsigned int n,
> > > uint64_t *scratch);
> > >
> > > "scratch"? "temp"? "tmp"?
> >
> > scratch is fine for me
>
> Fine with me.
Here's a full diff, works for me(tm), ok?
Index: sys/kern/kern_sysctl.c
===================================================================
RCS file: /cvs/src/sys/kern/kern_sysctl.c,v
retrieving revision 1.418
diff -u -p -r1.418 kern_sysctl.c
--- sys/kern/kern_sysctl.c 16 Jul 2023 03:01:31 -0000 1.418
+++ sys/kern/kern_sysctl.c 15 Sep 2023 13:29:53 -0000
@@ -519,7 +519,7 @@ kern_sysctl(int *name, u_int namelen, vo
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];
Index: sys/kern/subr_evcount.c
===================================================================
RCS file: /cvs/src/sys/kern/subr_evcount.c,v
retrieving revision 1.15
diff -u -p -r1.15 subr_evcount.c
--- sys/kern/subr_evcount.c 5 Dec 2022 08:58:49 -0000 1.15
+++ sys/kern/subr_evcount.c 15 Sep 2023 14:01:55 -0000
@@ -101,7 +101,7 @@ evcount_sysctl(int *name, u_int namelen,
{
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,
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;
Index: sys/kern/subr_percpu.c
===================================================================
RCS file: /cvs/src/sys/kern/subr_percpu.c,v
retrieving revision 1.10
diff -u -p -r1.10 subr_percpu.c
--- sys/kern/subr_percpu.c 3 Oct 2022 14:10:53 -0000 1.10
+++ sys/kern/subr_percpu.c 15 Sep 2023 14:16:41 -0000
@@ -159,17 +159,19 @@ counters_free(struct cpumem *cm, unsigne
}
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_
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, unsigne
}
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;
Index: sys/net/pfkeyv2_convert.c
===================================================================
RCS file: /cvs/src/sys/net/pfkeyv2_convert.c,v
retrieving revision 1.80
diff -u -p -r1.80 pfkeyv2_convert.c
--- sys/net/pfkeyv2_convert.c 7 Aug 2023 03:35:06 -0000 1.80
+++ sys/net/pfkeyv2_convert.c 15 Sep 2023 13:33:37 -0000
@@ -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);
Index: sys/net/if_pfsync.c
===================================================================
RCS file: /cvs/src/sys/net/if_pfsync.c,v
retrieving revision 1.320
diff -u -p -r1.320 if_pfsync.c
--- sys/net/if_pfsync.c 18 Aug 2023 08:03:57 -0000 1.320
+++ sys/net/if_pfsync.c 15 Sep 2023 13:33:42 -0000
@@ -3339,7 +3339,7 @@ pfsync_sysctl_pfsyncstat(void *oldp, siz
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)));
}
Index: sys/net/if_etherip.c
===================================================================
RCS file: /cvs/src/sys/net/if_etherip.c,v
retrieving revision 1.50
diff -u -p -r1.50 if_etherip.c
--- sys/net/if_etherip.c 28 Feb 2022 00:12:11 -0000 1.50
+++ sys/net/if_etherip.c 15 Sep 2023 13:33:58 -0000
@@ -789,7 +789,7 @@ etherip_sysctl_etheripstat(void *oldp, s
sizeof(uint64_t)));
memset(ðeripstat, 0, sizeof etheripstat);
counters_read(etheripcounters, (uint64_t *)ðeripstat,
- etherips_ncounters);
+ etherips_ncounters, NULL);
return (sysctl_rdstruct(oldp, oldlenp, newp, ðeripstat,
sizeof(etheripstat)));
}
Index: sys/net/if.c
===================================================================
RCS file: /cvs/src/sys/net/if.c,v
retrieving revision 1.707
diff -u -p -r1.707 if.c
--- sys/net/if.c 18 Aug 2023 08:10:16 -0000 1.707
+++ sys/net/if.c 15 Sep 2023 13:34:06 -0000
@@ -2797,7 +2797,8 @@ if_getdata(struct ifnet *ifp, struct if_
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];
Index: sys/net/pipex.c
===================================================================
RCS file: /cvs/src/sys/net/pipex.c,v
retrieving revision 1.148
diff -u -p -r1.148 pipex.c
--- sys/net/pipex.c 30 Aug 2022 19:42:29 -0000 1.148
+++ sys/net/pipex.c 15 Sep 2023 13:34:11 -0000
@@ -558,7 +558,7 @@ pipex_export_session_stats(struct pipex_
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];
Index: sys/net/rtsock.c
===================================================================
RCS file: /cvs/src/sys/net/rtsock.c,v
retrieving revision 1.369
diff -u -p -r1.369 rtsock.c
--- sys/net/rtsock.c 28 Jul 2023 09:33:16 -0000 1.369
+++ sys/net/rtsock.c 15 Sep 2023 13:34:14 -0000
@@ -2245,7 +2245,7 @@ sysctl_rtable_rtstat(void *oldp, size_t
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];
Index: sys/netinet/igmp.c
===================================================================
RCS file: /cvs/src/sys/netinet/igmp.c,v
retrieving revision 1.82
diff -u -p -r1.82 igmp.c
--- sys/netinet/igmp.c 8 Sep 2022 10:22:06 -0000 1.82
+++ sys/netinet/igmp.c 15 Sep 2023 13:34:20 -0000
@@ -687,7 +687,7 @@ igmp_sysctl_igmpstat(void *oldp, size_t
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];
Index: sys/netinet/ip_carp.c
===================================================================
RCS file: /cvs/src/sys/netinet/ip_carp.c,v
retrieving revision 1.357
diff -u -p -r1.357 ip_carp.c
--- sys/netinet/ip_carp.c 16 May 2023 14:32:54 -0000 1.357
+++ sys/netinet/ip_carp.c 15 Sep 2023 13:34:35 -0000
@@ -749,7 +749,8 @@ carp_sysctl_carpstat(void *oldp, size_t
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)));
}
Index: sys/netinet/ip_divert.c
===================================================================
RCS file: /cvs/src/sys/netinet/ip_divert.c,v
retrieving revision 1.91
diff -u -p -r1.91 ip_divert.c
--- sys/netinet/ip_divert.c 13 May 2023 13:35:17 -0000 1.91
+++ sys/netinet/ip_divert.c 15 Sep 2023 13:34:25 -0000
@@ -350,7 +350,7 @@ divert_sysctl_divstat(void *oldp, size_t
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];
Index: sys/netinet/ip_icmp.c
===================================================================
RCS file: /cvs/src/sys/netinet/ip_icmp.c,v
retrieving revision 1.191
diff -u -p -r1.191 ip_icmp.c
--- sys/netinet/ip_icmp.c 5 May 2022 13:57:40 -0000 1.191
+++ sys/netinet/ip_icmp.c 15 Sep 2023 13:34:40 -0000
@@ -917,7 +917,7 @@ icmp_sysctl_icmpstat(void *oldp, size_t
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];
Index: sys/netinet/ip_input.c
===================================================================
RCS file: /cvs/src/sys/netinet/ip_input.c,v
retrieving revision 1.386
diff -u -p -r1.386 ip_input.c
--- sys/netinet/ip_input.c 6 Sep 2023 11:09:43 -0000 1.386
+++ sys/netinet/ip_input.c 15 Sep 2023 13:34:45 -0000
@@ -1747,7 +1747,7 @@ ip_sysctl_ipstat(void *oldp, size_t *old
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];
Index: sys/netinet/ip_ipip.c
===================================================================
RCS file: /cvs/src/sys/netinet/ip_ipip.c,v
retrieving revision 1.98
diff -u -p -r1.98 ip_ipip.c
--- sys/netinet/ip_ipip.c 2 Jan 2022 22:36:04 -0000 1.98
+++ sys/netinet/ip_ipip.c 15 Sep 2023 13:34:56 -0000
@@ -573,7 +573,8 @@ ipip_sysctl_ipipstat(void *oldp, size_t
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)));
}
Index: sys/netinet/ipsec_input.c
===================================================================
RCS file: /cvs/src/sys/netinet/ipsec_input.c,v
retrieving revision 1.205
diff -u -p -r1.205 ipsec_input.c
--- sys/netinet/ipsec_input.c 7 Aug 2023 03:43:57 -0000 1.205
+++ sys/netinet/ipsec_input.c 15 Sep 2023 13:35:24 -0000
@@ -664,7 +664,7 @@ esp_sysctl_espstat(void *oldp, size_t *o
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 *old
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, siz
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_
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)));
}
Index: sys/netinet/tcp_usrreq.c
===================================================================
RCS file: /cvs/src/sys/netinet/tcp_usrreq.c,v
retrieving revision 1.221
diff -u -p -r1.221 tcp_usrreq.c
--- sys/netinet/tcp_usrreq.c 6 Jul 2023 09:15:24 -0000 1.221
+++ sys/netinet/tcp_usrreq.c 15 Sep 2023 13:47:13 -0000
@@ -1237,7 +1237,7 @@ tcp_sysctl_tcpstat(void *oldp, size_t *o
#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);
Index: sys/netinet/udp_usrreq.c
===================================================================
RCS file: /cvs/src/sys/netinet/udp_usrreq.c,v
retrieving revision 1.305
diff -u -p -r1.305 udp_usrreq.c
--- sys/netinet/udp_usrreq.c 22 Jan 2023 12:05:44 -0000 1.305
+++ sys/netinet/udp_usrreq.c 15 Sep 2023 13:47:17 -0000
@@ -1314,7 +1314,7 @@ udp_sysctl_udpstat(void *oldp, size_t *o
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];
Index: sys/netinet6/icmp6.c
===================================================================
RCS file: /cvs/src/sys/netinet6/icmp6.c,v
retrieving revision 1.248
diff -u -p -r1.248 icmp6.c
--- sys/netinet6/icmp6.c 5 Apr 2023 21:51:47 -0000 1.248
+++ sys/netinet6/icmp6.c 15 Sep 2023 13:46:12 -0000
@@ -1870,7 +1870,8 @@ icmp6_sysctl_icmp6stat(void *oldp, size_
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));
Index: sys/netinet6/ip6_divert.c
===================================================================
RCS file: /cvs/src/sys/netinet6/ip6_divert.c,v
retrieving revision 1.89
diff -u -p -r1.89 ip6_divert.c
--- sys/netinet6/ip6_divert.c 4 Apr 2023 10:12:03 -0000 1.89
+++ sys/netinet6/ip6_divert.c 15 Sep 2023 13:46:15 -0000
@@ -358,7 +358,7 @@ divert6_sysctl_div6stat(void *oldp, size
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];
Index: sys/netinet6/ip6_input.c
===================================================================
RCS file: /cvs/src/sys/netinet6/ip6_input.c,v
retrieving revision 1.255
diff -u -p -r1.255 ip6_input.c
--- sys/netinet6/ip6_input.c 6 Sep 2023 11:09:43 -0000 1.255
+++ sys/netinet6/ip6_input.c 15 Sep 2023 13:46:21 -0000
@@ -1466,7 +1466,7 @@ ip6_sysctl_ip6stat(void *oldp, size_t *o
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));
Index: sys/netinet6/raw_ip6.c
===================================================================
RCS file: /cvs/src/sys/netinet6/raw_ip6.c,v
retrieving revision 1.172
diff -u -p -r1.172 raw_ip6.c
--- sys/netinet6/raw_ip6.c 22 Jan 2023 12:05:44 -0000 1.172
+++ sys/netinet6/raw_ip6.c 15 Sep 2023 13:46:24 -0000
@@ -784,7 +784,8 @@ rip6_sysctl_rip6stat(void *oldp, size_t
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)));
Index: sys/sys/percpu.h
===================================================================
RCS file: /cvs/src/sys/sys/percpu.h,v
retrieving revision 1.8
diff -u -p -r1.8 percpu.h
--- sys/sys/percpu.h 28 Aug 2018 15:15:02 -0000 1.8
+++ sys/sys/percpu.h 15 Sep 2023 13:36:07 -0000
@@ -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 *
Index: sys/uvm/uvm_meter.c
===================================================================
RCS file: /cvs/src/sys/uvm/uvm_meter.c,v
retrieving revision 1.49
diff -u -p -r1.49 uvm_meter.c
--- sys/uvm/uvm_meter.c 18 Aug 2023 09:18:52 -0000 1.49
+++ sys/uvm/uvm_meter.c 15 Sep 2023 13:33:33 -0000
@@ -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];
Index: share/man/man9/counters_alloc.9
===================================================================
RCS file: /cvs/src/share/man/man9/counters_alloc.9,v
retrieving revision 1.12
diff -u -p -r1.12 counters_alloc.9
--- share/man/man9/counters_alloc.9 20 Feb 2022 23:11:01 -0000 1.12
+++ share/man/man9/counters_alloc.9 15 Sep 2023 14:08:55 -0000
@@ -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 th
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
