Date: Sat, 3 May 2008 22:06:52 GMT From: Luke Dean <luked@pobox.com> To: freebsd-gnats-submit@FreeBSD.org Subject: ports/123375: [patch] sysutils/wmmemmon fails with error extracting symbols Message-ID: <200805032206.m43M6qAT045484@www.freebsd.org> Resent-Message-ID: <200805032210.m43MA2Zt040939@freefall.freebsd.org>
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>Number: 123375
>Category: ports
>Synopsis: [patch] sysutils/wmmemmon fails with error extracting symbols
>Confidential: no
>Severity: serious
>Priority: low
>Responsible: freebsd-ports-bugs
>State: open
>Quarter:
>Keywords:
>Date-Required:
>Class: sw-bug
>Submitter-Id: current-users
>Arrival-Date: Sat May 03 22:10:02 UTC 2008
>Closed-Date:
>Last-Modified:
>Originator: Luke Dean
>Release: 7.0-STABLE
>Organization:
>Environment:
FreeBSD greentower.lukas.is-a-geek.org 7.0-STABLE FreeBSD 7.0-STABLE #0: Sun Apr 20 09:15:24 PDT 2008 lukas@greentower.lukas.is-a-geek.org:/usr/obj/usr/src/sys/CUSTOM i386
>Description:
sysutils/wmmemmon uses kvm to read kernel memory statistics. This has been broken since I upgraded from 6-STABLE to 7-STABLE.
I reported a similar problem with sysutils/wmcpuload and was advised that the port should be changed to use sysctl instead of kvm, because kvm no longer exposes the symbols this software needs.
I made this change and submitted a patch in response to PR #123047.
Now I'd like to do the same for sysutils/wmmemmon, since it suffers from the same problem.
>How-To-Repeat:
On 7-STABLE, install sysutils/wmmemmon
Attempt to run it.
It errors out with:
kvm_open: kvm_nlist: No such file or directory
error extracting symbols
>Fix:
Change the program to use sysctl instead of kvm to read memory stats.
I am submitting a patch that does this.
I have only tested it on my own system, but it seems to work well for me. I don't know how far back the support for the sysctls goes. This patch may not work so well for older FreeBSD releases. I am not a kernel hacker and my C skills are sorely lacking.
If someone more knowledgable would like to review this patch, improve or correct it if necessary, and commit it, I would be thankful.
(I'm adding a .txt to the end of the patch filename because GNATS won't accept it otherwise. If I remove the .txt and put the patch in /usr/ports/sysutils/wmmemmon/files, it applies when I build the port.)
Patch attached with submission follows:
--- src/mem_freebsd.c.orig 2002-10-14 05:23:26.000000000 -0700
+++ src/mem_freebsd.c 2008-05-03 13:46:06.000000000 -0700
@@ -17,38 +17,45 @@
#include <stdlib.h>
#include "mem.h"
-#include <kvm.h>
+#include <sys/types.h>
+#include <sys/sysctl.h>
+#include <vm/vm_param.h>
#include <fcntl.h>
-#include <sys/vmmeter.h>
#include <time.h>
-static kvm_t *kvm_data = NULL;
-static int pageshift;
-static struct nlist nlst[] = { {"_cp_time"}, {"_cnt"}, {0} };
+static int page_size_mib[4] = { -1, -1, -1, -1 };
+static int page_count_mib[4] = { -1, -1, -1, -1 };
+static int free_count_mib[4] = { -1, -1, -1, -1 };
+static int active_count_mib[4] = { -1, -1, -1, -1 };
+static int inactive_count_mib[4] = { -1, -1, -1, -1 };
+static int wire_count_mib[4] = { -1, -1, -1, -1 };
+static int cache_count_mib[4] = { -1, -1, -1, -1 };
+static int swappgsout_mib[4] = { -1, -1, -1, -1 };
+static int swappgsin_mib[4] = { -1, -1, -1, -1 };
+
+static size_t page_size_len = 4;
+static size_t page_count_len = 4;
+static size_t free_count_len = 4;
+static size_t active_count_len = 4;
+static size_t inactive_count_len = 4;
+static size_t wire_count_len = 4;
+static size_t cache_count_len = 4;
+static size_t swappgsout_len = 4;
+static size_t swappgsin_len = 4;
/* initialize function */
void mem_init(void)
{
- int pagesize = getpagesize();
- pageshift = 0;
+ init_mib("vm.stats.vm.v_page_size",page_size_mib,&page_size_len);
+ init_mib("vm.stats.vm.v_page_count",page_count_mib,&page_count_len);
+ init_mib("vm.stats.vm.v_free_count",free_count_mib,&free_count_len);
+ init_mib("vm.stats.vm.v_active_count",active_count_mib,&active_count_len);
+ init_mib("vm.stats.vm.v_inactive_count",inactive_count_mib,&inactive_count_len);
+ init_mib("vm.stats.vm.v_wire_count",wire_count_mib,&wire_count_len);
+ init_mib("vm.stats.vm.v_cache_count",cache_count_mib,&cache_count_len);
+ init_mib("vm.stats.vm.v_swappgsout",swappgsout_mib,&swappgsout_len);
+ init_mib("vm.stats.vm.v_swappgsin",swappgsin_mib,&swappgsin_len);
- while (pagesize > 1) {
- pageshift++;
- pagesize >>= 1;
- }
-
- kvm_data = kvm_open(NULL, NULL, NULL, O_RDONLY, "kvm_open");
-
- if (kvm_data == NULL) {
- fprintf(stderr, "can't open kernel virtual memory");
- exit(1);
- }
- kvm_nlist(kvm_data, nlst);
-
- if (nlst[0].n_type == 0 || nlst[1].n_type == 0) {
- fprintf(stderr, "error extracting symbols");
- exit(1);
- }
/* drop setgid & setuid (the latter should not be there really) */
seteuid(getuid());
setegid(getgid());
@@ -59,26 +66,38 @@
}
}
-
/* return mem/swap usage in percent 0 to 100 */
void mem_getusage(int *per_mem, int *per_swap, const struct mem_options *opts)
{
- struct vmmeter vm;
- int bufspace;
+ unsigned long int page_size;
+ unsigned long int page_count;
+ unsigned long int free_count;
+ unsigned long int active_count;
+ unsigned long int inactive_count;
+ unsigned long int wire_count;
+ unsigned long int cache_count;
+ long int swappgsout;
+ long int swappgsin;
+
+ static long int saved_swappgsout = -1;
+ static long int saved_swappgsin = -1;
+
static int swap_firsttime = 1;
- static int swappgsin = -1;
- static int swappgsout = -1;
- static int swapmax = 0, swapused = 0;
+ static long int swapmax = 0, swapused = 0;
time_t cur_time;
static time_t last_time_swap = 0;
u_int mused;
/* get mem usage */
- if (kvm_read(kvm_data, nlst[0].n_value, &bufspace, sizeof(bufspace)) !=
- sizeof(bufspace))
- exit(1);
- if (kvm_read(kvm_data, nlst[1].n_value, &vm, sizeof(vm)) != sizeof(vm))
- exit(1);
+ if (sysctl(page_size_mib, 4, &page_size, &page_size_len, NULL, 0) == -1) return;
+ if (sysctl(page_count_mib, 4, &page_count, &page_count_len, NULL, 0) == -1) return;
+ if (sysctl(free_count_mib, 4, &free_count, &free_count_len, NULL, 0) == -1) return;
+ if (sysctl(active_count_mib, 4, &active_count, &active_count_len, NULL, 0) == -1) return;
+ if (sysctl(inactive_count_mib, 4, &inactive_count, &inactive_count_len, NULL, 0) == -1) return;
+ if (sysctl(wire_count_mib, 4, &wire_count, &wire_count_len, NULL, 0) == -1) return;
+ if (sysctl(cache_count_mib, 4, &cache_count, &cache_count_len, NULL, 0) == -1) return;
+ if (sysctl(swappgsout_mib, 4, &swappgsout, &swappgsout_len, NULL, 0) == -1) return;
+ if (sysctl(swappgsin_mib, 4, &swappgsin, &swappgsin_len, NULL, 0) == -1) return;
/* get swap usage */
/* only calculate when first time or when changes took place */
@@ -86,45 +105,69 @@
/* otherwise it can eat up to 50% of CPU time on heavy swap activity */
cur_time = time(NULL);
if (swap_firsttime ||
- (((vm.v_swappgsin > swappgsin) || (vm.v_swappgsout > swappgsout))
+ (((swappgsin > saved_swappgsin) || (swappgsout > saved_swappgsout))
&& cur_time > last_time_swap + 1)) {
- struct kvm_swap swap;
- int n;
-
swapmax = 0;
swapused = 0;
- n = kvm_getswapinfo(kvm_data, &swap, 1, 0);
- if (n >= 0 && swap.ksw_total != 0) {
- swapmax = swap.ksw_total;
- swapused = swap.ksw_used;
- }
+ getswapinfo(&swapmax,&swapused);
swap_firsttime = 0;
last_time_swap = cur_time;
}
- swappgsin = vm.v_swappgsin;
- swappgsout = vm.v_swappgsout;
+ saved_swappgsin = swappgsin;
+ saved_swappgsout = swappgsout;
#ifdef DEBUG
printf ("-------------------\n");
- printf ("total:%10d\n", vm.v_page_count * vm.v_page_size);
- printf ("free :%10d\n", vm.v_free_count * vm.v_page_size);
- printf ("act :%10d\n", vm.v_active_count * vm.v_page_size);
- printf ("inact:%10d\n", vm.v_inactive_count * vm.v_page_size);
- printf ("wired:%10d\n", vm.v_wire_count * vm.v_page_size);
- printf ("cache:%10d\n", vm.v_cache_count * vm.v_page_size);
+ printf ("total:%10d\n", page_count * page_size);
+ printf ("free :%10d\n", free_count * page_size);
+ printf ("act :%10d\n", active_count * page_size);
+ printf ("inact:%10d\n", inactive_count * page_size);
+ printf ("wired:%10d\n", wire_count * page_size);
+ printf ("cache:%10d\n", cache_count * page_size);
printf ("-------------------\n");
#endif
/* calc mem/swap usage in percent */
- mused = vm.v_page_count - vm.v_free_count;
- if (opts->ignore_wired) mused -= vm.v_wire_count;
- if (opts->ignore_cached) mused -= vm.v_cache_count;
+ mused = page_count - free_count;
+ if (opts->ignore_wired) mused -= wire_count;
+ if (opts->ignore_cached) mused -= cache_count;
- *per_mem = 100 * (double) mused / (double) vm.v_page_count;
+ *per_mem = 100 * (double) mused / (double) page_count;
*per_swap = 100 * (double) swapused / (double) swapmax;
if (*per_mem > 97) *per_mem = 100;
}
+
+/* sets up the mib for a sysctl */
+void init_mib(char *sysctlname, int *mib, size_t *len)
+{
+ if (sysctlnametomib(sysctlname,mib,len) == -1) {
+ fprintf(stderr, "bad sysctl %s\n", sysctlname);
+ exit(1);
+ }
+}
+
+/* returns total and used number of swap pages */
+void getswapinfo (long *swapmax, long *swapused)
+{
+ size_t miblen, size;
+ int mib[16], n;
+ struct xswdev xsw;
+
+ miblen = sizeof mib / sizeof mib[0];
+ init_mib("vm.swap_info",mib,&miblen);
+
+ for (n=0;; n++)
+ {
+ mib[miblen] = n;
+ size = sizeof xsw;
+ if (sysctl(mib,miblen+1,&xsw,&size,NULL,0) == -1)
+ break;
+ *swapmax += (long) xsw.xsw_nblks;
+ *swapused += (long) xsw.xsw_used;
+ }
+}
+
>Release-Note:
>Audit-Trail:
>Unformatted:
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