bin/135893: 'vmstat -s -M core' is broken

[Mikolaj Golub]

>Number:         135893
>Category:       bin
>Synopsis:       'vmstat -s -M core' is broken
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Sun Jun 21 18:40:00 UTC 2009
>Closed-Date:
>Last-Modified:
>Originator:     Mikolaj Golub
>Release:        
>Organization:
>Environment:
FreeBSD fbsd.zhuzha.ua1 8.0-CURRENT FreeBSD 8.0-CURRENT #0 r193993M: Thu Jun 11 17:01:46 EEST 2009     root at zhuzha.ua1:/home/golub/freebsd/build/obj/home/golub/freebsd/src/sys/GENERIC  i386

FreeBSD zhuzha.ua1 7.2-STABLE FreeBSD 7.2-STABLE #18: Wed Jun  3 14:28:49 EEST 2009     root at zhuzha.ua1:/usr/obj/usr/src/sys/DEBUG  i386
>Description:
'vmstat -s -M core' is broken, printing 0 for most of the counters.

This is because vmstat looks for statistics only in global `cnt' while the values of most of the counters are collected now in per-CPU variables.
>How-To-Repeat:
vmstat -s -M /dev/mem -N /boot/kernel/kernel

and compare with output of

vmstat -s
>Fix:
Attached patch fixes this.

Patch attached with submission follows:

--- usr.bin/vmstat/vmstat.c.orig	2009-02-22 04:11:24.000000000 +0200
+++ usr.bin/vmstat/vmstat.c	2009-06-21 20:51:20.000000000 +0300
@@ -58,6 +58,7 @@
 #include <sys/resource.h>
 #include <sys/sysctl.h>
 #include <sys/vmmeter.h>
+#include <sys/pcpu.h>
 
 #include <vm/vm_param.h>
 
@@ -418,10 +419,93 @@
 }
 
 static void
+fill_pcpu(struct pcpu ***p, int* maxcpup) {
+	struct pcpu **pp;
+	
+	int maxcpu, size, i;
+
+	*p = NULL;
+	
+	if (kd == NULL)
+		return;
+
+	maxcpu = kvm_getmaxcpu(kd);
+	if(maxcpu < 0)
+		errx(1, "kvm_getcptime: %s", kvm_geterr(kd));
+	if(maxcpu == 0) /* XXX: not sure this check makes sence */
+		return;
+
+	size = sizeof(struct pcpu *) * maxcpu;
+	pp = (struct pcpu **)calloc(1, size);
+	if(pp == NULL)
+		err(1, "malloc %zd bytes", size);
+
+	for(i = 0; i < maxcpu; i++) {
+		pp[i] = kvm_getpcpu(kd, i);
+		if(pp[i] == (struct pcpu *)-1)
+			errx(1, "kvm_getpcpu: %s", kvm_geterr(kd));
+	}
+
+	*maxcpup = maxcpu;
+	*p = pp;
+	return;
+}
+
+static void
+free_pcpu(struct pcpu **p, int maxcpu) {
+	int i;
+	for(i = 0; i < maxcpu; i++)
+		free(p[i]);
+	free(p);
+	p = NULL;
+}
+
+static void
 fill_vmmeter(struct vmmeter *vmmp)
 {
 	if (kd != NULL) {
+		struct pcpu **ppcpup;
+		int maxcpu, i;
+		
 		kread(X_SUM, vmmp, sizeof(*vmmp));
+		
+		fill_pcpu(&ppcpup, &maxcpu);
+		for(i=0; i < maxcpu; i++) {
+			if(ppcpup[i] == NULL)
+				continue;
+#define ADD_FROM_PCPU(i, name) \
+			vmmp->name += ppcpup[i]->pc_cnt.name
+			ADD_FROM_PCPU(i, v_swtch);
+			ADD_FROM_PCPU(i, v_trap);
+			ADD_FROM_PCPU(i, v_syscall);
+			ADD_FROM_PCPU(i, v_intr);
+			ADD_FROM_PCPU(i, v_soft);
+			ADD_FROM_PCPU(i, v_vm_faults);
+			ADD_FROM_PCPU(i, v_cow_faults);
+			ADD_FROM_PCPU(i, v_cow_optim);
+			ADD_FROM_PCPU(i, v_zfod);
+			ADD_FROM_PCPU(i, v_ozfod);
+			ADD_FROM_PCPU(i, v_swapin);
+			ADD_FROM_PCPU(i, v_swapout);
+			ADD_FROM_PCPU(i, v_swappgsin);
+			ADD_FROM_PCPU(i, v_swappgsout);
+			ADD_FROM_PCPU(i, v_vnodein);
+			ADD_FROM_PCPU(i, v_vnodeout);
+			ADD_FROM_PCPU(i, v_vnodepgsin);
+			ADD_FROM_PCPU(i, v_vnodepgsout);
+			ADD_FROM_PCPU(i, v_intrans);
+			ADD_FROM_PCPU(i, v_tfree);
+			ADD_FROM_PCPU(i, v_forks);
+			ADD_FROM_PCPU(i, v_vforks);
+			ADD_FROM_PCPU(i, v_rforks);
+			ADD_FROM_PCPU(i, v_kthreads);
+			ADD_FROM_PCPU(i, v_forkpages);
+			ADD_FROM_PCPU(i, v_vforkpages);
+			ADD_FROM_PCPU(i, v_rforkpages);
+			ADD_FROM_PCPU(i, v_kthreadpages);
+#undef ADD_FROM_PCPU
+		}
+		free_pcpu(ppcpup, maxcpu);
 	} else {
 		size_t size = sizeof(unsigned int);
 #define GET_VM_STATS(cat, name) \


>Release-Note:
>Audit-Trail:
>Unformatted: