From 56081d37f368e69c95c8e9e8635623e915dae8f1 Mon Sep 17 00:00:00 2001
From: martijn <martijn@openbsd.org>
Date: Tue, 24 Oct 2023 18:16:05 +0000
Subject: [PATCH] Add support for HOST-RESOURCES-MIB:hrSWRunPerfTable by adding
 hrSWRunPerfCPU and hrSWRunPerfMem. This allows snmptop to work with snmpd(8).
 Math copied from top(1).

OK tb@
---
 libexec/snmpd/snmpd_metrics/mib.c | 36 ++++++++++++++++++++++++++++++-
 1 file changed, 35 insertions(+), 1 deletion(-)

diff --git a/libexec/snmpd/snmpd_metrics/mib.c b/libexec/snmpd/snmpd_metrics/mib.c
index 0846307f5d9..8c3e8eb32bb 100644
--- a/libexec/snmpd/snmpd_metrics/mib.c
+++ b/libexec/snmpd/snmpd_metrics/mib.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mib.c,v 1.4 2023/07/04 11:34:19 sashan Exp $	*/
+/*	$OpenBSD: mib.c,v 1.5 2023/10/24 18:16:05 martijn Exp $	*/
 
 /*
  * Copyright (c) 2022 Martijn van Duren <martijn@openbsd.org>
@@ -69,6 +69,10 @@ struct event		 connev;
 const char		*agentxsocket = NULL;
 int			 agentxfd = -1;
 
+int			 pageshift;
+#define pagetok(size) ((size) << pageshift)
+
+void		 pageshift_init(void);
 void		 snmp_connect(struct agentx *, void *, int);
 void		 snmp_tryconnect(int, short, void *);
 void		 snmp_read(int, short, void *);
@@ -89,6 +93,7 @@ struct agentx_object *hrProcessorLoad;
 struct agentx_index *hrSWRunIdx;
 struct agentx_object *hrSWRunIndex, *hrSWRunName, *hrSWRunID, *hrSWRunPath;
 struct agentx_object *hrSWRunParameters, *hrSWRunType, *hrSWRunStatus;
+struct agentx_object *hrSWRunPerfCPU, *hrSWRunPerfMem;
 
 void	 mib_hrsystemuptime(struct agentx_varbind *);
 void	 mib_hrsystemdate(struct agentx_varbind *);
@@ -634,6 +639,7 @@ mib_hrswrun(struct agentx_varbind *vb)
 	struct agentx_object		*obj;
 	enum agentx_request_type	 req;
 	int32_t				 idx;
+	int32_t				 time;
 	struct kinfo_proc		*kinfo;
 	char				*s;
 
@@ -711,6 +717,13 @@ mib_hrswrun(struct agentx_varbind *vb)
 			agentx_varbind_integer(vb, 4);
 			break;
 		}
+	} else if (obj == hrSWRunPerfCPU) {
+		time = kinfo->p_rtime_sec * 100;
+		time += (kinfo->p_rtime_usec + 5000) / 10000;
+		agentx_varbind_integer(vb, time);
+	} else if (obj == hrSWRunPerfMem) {
+		agentx_varbind_integer(vb, pagetok(kinfo->p_vm_tsize +
+		    kinfo->p_vm_dsize + kinfo->p_vm_ssize));
 	} else
 		fatal("%s: Unexpected object", __func__);
 }
@@ -3278,6 +3291,7 @@ main(int argc, char *argv[])
 	kr_init();
 	pf_init();
 	timer_init();
+	pageshift_init();
 
 	if (agentxsocket != NULL) {
 		if (strlcpy(agentxsocketdir, agentxsocket,
@@ -3375,6 +3389,10 @@ main(int argc, char *argv[])
 	    (hrSWRunType = agentx_object(host, AGENTX_OID(HRSWRUNTYPE),
 	    &hrSWRunIdx, 1, 0, mib_hrswrun)) == NULL ||
 	    (hrSWRunStatus = agentx_object(host, AGENTX_OID(HRSWRUNSTATUS),
+	    &hrSWRunIdx, 1, 0, mib_hrswrun)) == NULL ||
+	    (hrSWRunPerfCPU = agentx_object(host, AGENTX_OID(HRSWRUNPERFCPU),
+	    &hrSWRunIdx, 1, 0, mib_hrswrun)) == NULL ||
+	    (hrSWRunPerfMem = agentx_object(host, AGENTX_OID(HRSWRUNPERFMEM),
 	    &hrSWRunIdx, 1, 0, mib_hrswrun)) == NULL)
 		fatal("agentx_object");
 
@@ -4320,6 +4338,22 @@ main(int argc, char *argv[])
 	event_dispatch();
 }
 
+#define LOG1024		 10
+void
+pageshift_init(void)
+{
+	long pagesize;
+
+	if ((pagesize = sysconf(_SC_PAGESIZE)) == -1)
+		fatal("sysconf(_SC_PAGESIZE)");
+	while (pagesize > 1) {
+		pageshift++;
+		pagesize >>= 1;
+	}
+	/* we only need the amount of log(2)1024 for our conversion */
+	pageshift -= LOG1024;
+}
+
 void
 snmp_connect(struct agentx *sa, void *cookie, int close)
 {
-- 
2.20.1