/*
** Copyright (C) 2001-2025 Zabbix SIA
**
** This program is free software: you can redistribute it and/or modify it under the terms of
** the GNU Affero General Public License as published by the Free Software Foundation, version 3.
**
** This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
** without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
** See the GNU Affero General Public License for more details.
**
** You should have received a copy of the GNU Affero General Public License along with this program.
** If not, see <https://www.gnu.org/licenses/>.
**/
#include "zbxkstat.h"
#if defined(HAVE_KSTAT_H) && defined(HAVE_VMINFO_T_UPDATES)
#include "zbxsysinfo.h"
#include "stats.h"
#include "zbxmutexs.h"
#include "zbxstr.h"
static kstat_ctl_t *kc = NULL;
static kid_t kc_id = 0;
static kstat_t *kc_vminfo;
static zbx_mutex_t kstat_lock = ZBX_MUTEX_NULL;
/******************************************************************************
* *
* Purpose: refreshes kstat environment *
* *
* Parameters: error - [OUT] error message *
* *
* Return value: SUCCEED - kstat environment was refreshed successfully *
* FAIL - otherwise *
* *
******************************************************************************/
static int zbx_kstat_refresh(char **error)
{
int ret;
kid_t kid;
zabbix_log(LOG_LEVEL_DEBUG, "In %s()", __func__);
if (-1 == (kid = kstat_chain_update(kc)))
{
*error = zbx_dsprintf(*error, "failed to update kstat chain: %s", zbx_strerror(errno));
ret = FAIL;
goto out;
}
if (0 != kid)
kc_id = kid;
if (NULL == (kc_vminfo = kstat_lookup(kc, "unix", -1, "vminfo")))
{
*error = zbx_dsprintf(*error, "failed to find vminfo data: %s", zbx_strerror(errno));
ret = FAIL;
goto out;
}
ret = SUCCEED;
out:
zabbix_log(LOG_LEVEL_DEBUG, "End of %s()", __func__);
return ret;
}
/******************************************************************************
* *
* Purpose: initializes kstat environment *
* *
* Parameters: kstat - [IN] kstat data storage *
* error - [OUT] error message *
* *
* Return value: SUCCEED - kstat environment was initialized successfully *
* FAIL - otherwise *
* *
******************************************************************************/
int zbx_kstat_init(zbx_kstat_t *kstat, char **error)
{
char *errmsg = NULL;
int ret = FAIL;
zabbix_log(LOG_LEVEL_DEBUG, "In %s()", __func__);
if (NULL == (kc = kstat_open()))
{
*error = zbx_dsprintf(*error, "failed to open kstat: %s", zbx_strerror(errno));
goto out;
}
kc_id = kc->kc_chain_id;
if (SUCCEED != zbx_kstat_refresh(error))
goto out;
if (SUCCEED != (ret = zbx_mutex_create(&kstat_lock, ZBX_MUTEX_KSTAT, &errmsg)))
{
*error = zbx_dsprintf(*error, "failed to create kstat collector mutex : %s", errmsg);
zbx_free(errmsg);
}
memset(kstat, 0, sizeof(zbx_kstat_t));
out:
if (SUCCEED != ret && NULL != kc)
{
if (-1 == kstat_close(kc))
zabbix_log(LOG_LEVEL_DEBUG, "Failed to close kstat");
kc = NULL;
}
zabbix_log(LOG_LEVEL_DEBUG, "End of %s()", __func__);
return ret;
}
void zbx_kstat_destroy(void)
{
zabbix_log(LOG_LEVEL_DEBUG, "In %s()", __func__);
if (NULL == kc)
{
zabbix_log(LOG_LEVEL_DEBUG, "kc is NULL");
goto out;
}
if (-1 == kstat_close(kc))
zabbix_log(LOG_LEVEL_DEBUG, "Failed to close kstat");
zbx_mutex_destroy(&kstat_lock);
out:
zabbix_log(LOG_LEVEL_DEBUG, "End of %s()", __func__);
}
/******************************************************************************
* *
* Purpose: collects kstat stats *
* *
* Comments: This function is called every second to collect statistics. *
* *
******************************************************************************/
void zbx_kstat_collect(zbx_kstat_t *kstat)
{
kid_t kid;
char *error = NULL;
vminfo_t vminfo;
zabbix_log(LOG_LEVEL_DEBUG, "In %s()", __func__);
while (-1 == (kid = kstat_read(kc, kc_vminfo, &vminfo)) || kc_id != kid)
{
if (-1 == kid)
zabbix_log(LOG_LEVEL_DEBUG, "cannot collect kstat data, kstat_read: %s", ZBX_NULL2STR(error));
if (SUCCEED != zbx_kstat_refresh(&error))
{
zabbix_log(LOG_LEVEL_WARNING, "cannot collect kstat data, kstat_refresh: %s",
ZBX_NULL2STR(error));
zbx_free(error);
goto out;
}
}
zbx_mutex_lock(kstat_lock);
kstat->vminfo_index ^= 1;
kstat->vminfo[kstat->vminfo_index].freemem = vminfo.freemem;
kstat->vminfo[kstat->vminfo_index].updates = time(NULL);
zbx_mutex_unlock(kstat_lock);
zabbix_log(LOG_LEVEL_DEBUG, "vm_index: %d, freemem: " ZBX_FS_UI64 ", updates: " ZBX_FS_UI64,
(int)kstat->vminfo_index, kstat->vminfo[kstat->vminfo_index].freemem,
kstat->vminfo[kstat->vminfo_index].updates);
out:
zabbix_log(LOG_LEVEL_DEBUG, "End of %s()", __func__);
}
/******************************************************************************
* *
* Purpose: gets free memory size *
* *
* Parameters: value - [OUT] free memory size in bytes *
* error - [OUT] error message *
* *
* Return value: SUCCEED - free memory size was stored in value *
* FAIL - Either an error occurred (error parameter is set) or *
* data was not collected yet (error parameter is left *
* unchanged). *
* *
******************************************************************************/
int zbx_kstat_get_freemem(zbx_uint64_t *value, char **error)
{
int sysconf_pagesize, last, prev, ret = FAIL;
zbx_kstat_vminfo_t *vminfo;
zabbix_log(LOG_LEVEL_DEBUG, "In %s(): collector:%p", __func__, get_collector());
zbx_mutex_lock(kstat_lock);
if (NULL == get_collector())
goto out;
last = (get_collector())->kstat.vminfo_index;
prev = last ^ 1;
vminfo = (get_collector())->kstat.vminfo;
if (0 != vminfo[prev].updates && vminfo[prev].updates < vminfo[last].updates)
{
if (-1 == (sysconf_pagesize = sysconf(_SC_PAGESIZE)))
{
zabbix_log(LOG_LEVEL_DEBUG, "sysconf(_SC_PAGESIZE) failed, errno is: %s", zbx_strerror(errno));
goto out;
}
*value = (vminfo[last].freemem - vminfo[prev].freemem) /
(vminfo[last].updates - vminfo[prev].updates) * sysconf_pagesize;
ret = SUCCEED;
}
else
zabbix_log(LOG_LEVEL_DEBUG, "no new vminfo update is available");
out:
zbx_mutex_unlock(kstat_lock);
if (NULL == get_collector())
{
*error = zbx_strdup(*error, "Collector is not started.");
zabbix_log(LOG_LEVEL_DEBUG, "Collector is not started");
}
else
{
zabbix_log(LOG_LEVEL_DEBUG, "last: %d, prev: %d, vminfo[prev].updates: " ZBX_FS_UI64
", vminfo[last].updates: " ZBX_FS_UI64, last, prev, vminfo[prev].updates,
vminfo[last].updates);
}
zabbix_log(LOG_LEVEL_DEBUG, "End of %s()", __func__);
return ret;
}
#endif /*#if defined(HAVE_KSTAT_H) && defined(HAVE_VMINFO_T_UPDATES)*/