925 lines
31 KiB
C
925 lines
31 KiB
C
/*
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* This file is distributed as part of the SkySQL Gateway. It is free
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* software: you can redistribute it and/or modify it under the terms of the
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* GNU General Public License as published by the Free Software Foundation,
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* version 2.
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*
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* This program is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
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* FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
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* details.
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*
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* You should have received a copy of the GNU General Public License along with
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* this program; if not, write to the Free Software Foundation, Inc., 51
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* Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Copyright SkySQL Ab 2013
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*/
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#include <stdio.h>
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#include <string.h>
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#include <unistd.h>
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#include <stdlib.h>
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#include <sys/epoll.h>
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#include <errno.h>
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#include <poll.h>
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#include <dcb.h>
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#include <atomic.h>
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#include <gwbitmask.h>
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#include <skygw_utils.h>
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#include <log_manager.h>
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#include <gw.h>
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#include <config.h>
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#include <housekeeper.h>
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extern int lm_enabled_logfiles_bitmask;
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/**
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* @file poll.c - Abstraction of the epoll functionality
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*
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* @verbatim
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* Revision History
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*
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* Date Who Description
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* 19/06/13 Mark Riddoch Initial implementation
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* 28/06/13 Mark Riddoch Added poll mask support and DCB
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* zombie management
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* 29/08/14 Mark Riddoch Addition of thread status data, load average
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* etc.
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* 23/09/14 Mark Riddoch Make use of RDHUP conditional to allow CentOS 5
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* builds.
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*
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* @endverbatim
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*/
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/**
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* Control the use of mutexes for the epoll_wait call. Setting to 1 will
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* cause the epoll_wait calls to be moved under a mutex. This may be useful
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* for debuggign purposes but should be avoided in general use.
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*/
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#define MUTEX_EPOLL 0
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static int epoll_fd = -1; /*< The epoll file descriptor */
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static int do_shutdown = 0; /*< Flag the shutdown of the poll subsystem */
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static GWBITMASK poll_mask;
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#if MUTEX_EPOLL
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static simple_mutex_t epoll_wait_mutex; /*< serializes calls to epoll_wait */
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#endif
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static int n_waiting = 0; /*< No. of threads in epoll_wait */
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/**
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* Thread load average, this is the average number of descriptors in each
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* poll completion, a value of 1 or less is the ideal.
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*/
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static double load_average = 0.0;
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static int load_samples = 0;
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static int load_nfds = 0;
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static double current_avg = 0.0;
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static double *avg_samples = NULL;
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static int next_sample = 0;
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static int n_avg_samples;
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/* Thread statistics data */
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static int n_threads; /*< No. of threads */
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/**
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* Internal MaxScale thread states
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*/
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typedef enum { THREAD_STOPPED, THREAD_IDLE,
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THREAD_POLLING, THREAD_PROCESSING,
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THREAD_ZPROCESSING } THREAD_STATE;
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/**
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* Thread data used to report the current state and activity related to
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* a thread
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*/
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typedef struct {
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THREAD_STATE state; /*< Current thread state */
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int n_fds; /*< No. of descriptors thread is processing */
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DCB *cur_dcb; /*< Current DCB being processed */
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uint32_t event; /*< Current event being processed */
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} THREAD_DATA;
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static THREAD_DATA *thread_data = NULL; /*< Status of each thread */
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/**
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* The number of buckets used to gather statistics about how many
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* descriptors where processed on each epoll completion.
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*
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* An array of wakeup counts is created, with the number of descriptors used
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* to index that array. Each time a completion occurs the n_fds - 1 value is
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* used to index this array and increment the count held there.
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* If n_fds - 1 >= MAXFDS then the count at MAXFDS -1 is incremented.
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*/
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#define MAXNFDS 10
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/**
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* The polling statistics
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*/
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static struct {
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int n_read; /*< Number of read events */
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int n_write; /*< Number of write events */
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int n_error; /*< Number of error events */
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int n_hup; /*< Number of hangup events */
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int n_accept; /*< Number of accept events */
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int n_polls; /*< Number of poll cycles */
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int n_nothreads; /*< Number of times no threads are polling */
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int n_fds[MAXNFDS]; /*< Number of wakeups with particular
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n_fds value */
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} pollStats;
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/**
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* How frequently to call the poll_loadav function used to monitor the load
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* average of the poll subsystem.
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*/
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#define POLL_LOAD_FREQ 10
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/**
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* Periodic function to collect load data for average calculations
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*/
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static void poll_loadav(void *);
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/**
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* Initialise the polling system we are using for the gateway.
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*
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* In this case we are using the Linux epoll mechanism
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*/
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void
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poll_init()
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{
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int i;
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if (epoll_fd != -1)
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return;
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if ((epoll_fd = epoll_create(MAX_EVENTS)) == -1)
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{
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perror("epoll_create");
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exit(-1);
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}
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memset(&pollStats, 0, sizeof(pollStats));
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bitmask_init(&poll_mask);
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n_threads = config_threadcount();
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if ((thread_data =
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(THREAD_DATA *)malloc(n_threads * sizeof(THREAD_DATA))) != NULL)
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{
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for (i = 0; i < n_threads; i++)
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{
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thread_data[i].state = THREAD_STOPPED;
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}
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}
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#if MUTEX_EPOLL
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simple_mutex_init(&epoll_wait_mutex, "epoll_wait_mutex");
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#endif
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hktask_add("Load Average", poll_loadav, NULL, POLL_LOAD_FREQ);
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n_avg_samples = 15 * 60 / POLL_LOAD_FREQ;
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avg_samples = (double *)malloc(sizeof(double *) * n_avg_samples);
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for (i = 0; i < n_avg_samples; i++)
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avg_samples[i] = 0.0;
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}
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/**
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* Add a DCB to the set of descriptors within the polling
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* environment.
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*
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* @param dcb The descriptor to add to the poll
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* @return -1 on error or 0 on success
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*/
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int
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poll_add_dcb(DCB *dcb)
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{
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int rc = -1;
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dcb_state_t old_state = DCB_STATE_UNDEFINED;
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dcb_state_t new_state;
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struct epoll_event ev;
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CHK_DCB(dcb);
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#ifdef EPOLLRDHUP
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ev.events = EPOLLIN | EPOLLOUT | EPOLLRDHUP | EPOLLHUP | EPOLLET;
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#else
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ev.events = EPOLLIN | EPOLLOUT | EPOLLHUP | EPOLLET;
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#endif
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ev.data.ptr = dcb;
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/*<
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* Choose new state according to the role of dcb.
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*/
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if (dcb->dcb_role == DCB_ROLE_REQUEST_HANDLER) {
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new_state = DCB_STATE_POLLING;
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} else {
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ss_dassert(dcb->dcb_role == DCB_ROLE_SERVICE_LISTENER);
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new_state = DCB_STATE_LISTENING;
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}
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/*<
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* If dcb is in unexpected state, state change fails indicating that dcb
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* is not polling anymore.
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*/
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if (dcb_set_state(dcb, new_state, &old_state)) {
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rc = epoll_ctl(epoll_fd, EPOLL_CTL_ADD, dcb->fd, &ev);
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if (rc != 0) {
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int eno = errno;
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errno = 0;
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LOGIF(LE, (skygw_log_write_flush(
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LOGFILE_ERROR,
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"Error : Adding dcb %p in state %s "
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"to poll set failed. epoll_ctl failed due "
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"%d, %s.",
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dcb,
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STRDCBSTATE(dcb->state),
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eno,
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strerror(eno))));
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} else {
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LOGIF(LD, (skygw_log_write(
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LOGFILE_DEBUG,
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"%lu [poll_add_dcb] Added dcb %p in state %s to "
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"poll set.",
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pthread_self(),
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dcb,
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STRDCBSTATE(dcb->state))));
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}
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ss_dassert(rc == 0); /*< trap in debug */
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} else {
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LOGIF(LE, (skygw_log_write_flush(
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LOGFILE_ERROR,
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"Error : Unable to set new state for dcb %p "
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"in state %s. Adding to poll set failed.",
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dcb,
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STRDCBSTATE(dcb->state))));
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}
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return rc;
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}
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/**
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* Remove a descriptor from the set of descriptors within the
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* polling environment.
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* The state change command may fail because concurrent threads may call
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* dcb_set_state simultaneously and the conflict is prevented in dcb_set_state.
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*
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* @param dcb The descriptor to remove
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* @return -1 on error or 0 on success
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*/
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int
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poll_remove_dcb(DCB *dcb)
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{
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struct epoll_event ev;
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int rc = -1;
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dcb_state_t old_state = DCB_STATE_UNDEFINED;
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dcb_state_t new_state = DCB_STATE_NOPOLLING;
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CHK_DCB(dcb);
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/*< It is possible that dcb has already been removed from the set */
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if (dcb->state != DCB_STATE_POLLING) {
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if (dcb->state == DCB_STATE_NOPOLLING ||
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dcb->state == DCB_STATE_ZOMBIE)
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{
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rc = 0;
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}
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goto return_rc;
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}
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/*<
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* Set state to NOPOLLING and remove dcb from poll set.
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*/
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if (dcb_set_state(dcb, new_state, &old_state)) {
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rc = epoll_ctl(epoll_fd, EPOLL_CTL_DEL, dcb->fd, &ev);
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if (rc != 0) {
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int eno = errno;
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errno = 0;
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LOGIF(LE, (skygw_log_write_flush(
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LOGFILE_ERROR,
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"Error : epoll_ctl failed due %d, %s.",
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eno,
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strerror(eno))));
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}
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ss_dassert(rc == 0); /*< trap in debug */
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}
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/*<
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* This call was redundant, but the end result is correct.
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*/
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else if (old_state == new_state)
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{
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rc = 0;
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goto return_rc;
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}
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/*< Set bit for each maxscale thread */
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bitmask_copy(&dcb->memdata.bitmask, poll_bitmask());
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rc = 0;
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return_rc:
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return rc;
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}
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#define BLOCKINGPOLL 0 /*< Set BLOCKING POLL to 1 if using a single thread and to make
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* debugging easier.
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*/
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/**
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* The main polling loop
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*
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* This routine does the polling and despatches of IO events
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* to the DCB's. It may be called either directly or as the entry point
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* of a polling thread within the gateway.
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*
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* The routine will loop as long as the variable "shutdown" is set to zero,
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* setting this to a non-zero value will cause the polling loop to return.
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*
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* There are two options for the polling, a debug option that is only useful if
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* you have a single thread. This blocks in epoll_wait until an event occurs.
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*
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* The non-debug option does an epoll with a time out. This allows the checking of
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* shutdown value to be checked in all threads. The algorithm for polling in this
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* mode is to do a poll with no-wait, if no events are detected then the poll is
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* repeated with a time out. This allows for a quick check before making the call
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* with timeout. The call with the timeout differs in that the Linux scheduler may
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* deschedule a process if a timeout is included, but will not do this if a 0 timeout
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* value is given. this improves performance when the gateway is under heavy load.
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*
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* @param arg The thread ID passed as a void * to satisfy the threading package
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*/
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void
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poll_waitevents(void *arg)
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{
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struct epoll_event events[MAX_EVENTS];
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int i, nfds;
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int thread_id = (int)arg;
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bool no_op = false;
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static bool process_zombies_only = false; /*< flag for all threads */
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DCB *zombies = NULL;
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/** Add this thread to the bitmask of running polling threads */
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bitmask_set(&poll_mask, thread_id);
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if (thread_data)
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{
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thread_data[thread_id].state = THREAD_IDLE;
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}
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/** Init mysql thread context for use with a mysql handle and a parser */
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mysql_thread_init();
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while (1)
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{
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atomic_add(&n_waiting, 1);
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#if BLOCKINGPOLL
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nfds = epoll_wait(epoll_fd, events, MAX_EVENTS, -1);
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atomic_add(&n_waiting, -1);
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#else /* BLOCKINGPOLL */
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if (!no_op) {
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LOGIF(LD, (skygw_log_write(
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LOGFILE_DEBUG,
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"%lu [poll_waitevents] MaxScale thread "
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"%d > epoll_wait <",
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pthread_self(),
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thread_id)));
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no_op = TRUE;
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}
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#if MUTEX_EPOLL
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simple_mutex_lock(&epoll_wait_mutex, TRUE);
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#endif
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if (thread_data)
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{
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thread_data[thread_id].state = THREAD_POLLING;
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}
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if ((nfds = epoll_wait(epoll_fd, events, MAX_EVENTS, 0)) == -1)
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{
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atomic_add(&n_waiting, -1);
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int eno = errno;
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errno = 0;
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LOGIF(LD, (skygw_log_write(
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LOGFILE_DEBUG,
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"%lu [poll_waitevents] epoll_wait returned "
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"%d, errno %d",
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pthread_self(),
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nfds,
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eno)));
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no_op = FALSE;
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}
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else if (nfds == 0)
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{
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atomic_add(&n_waiting, -1);
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if (process_zombies_only) {
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#if MUTEX_EPOLL
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simple_mutex_unlock(&epoll_wait_mutex);
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#endif
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goto process_zombies;
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} else {
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nfds = epoll_wait(epoll_fd,
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events,
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MAX_EVENTS,
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EPOLL_TIMEOUT);
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/*<
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* When there are zombies to be cleaned up but
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* no client requests, allow all threads to call
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* dcb_process_zombies without having to wait
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* for the timeout.
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*/
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if (nfds == 0 && dcb_get_zombies() != NULL)
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{
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process_zombies_only = true;
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}
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}
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}
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else
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{
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atomic_add(&n_waiting, -1);
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}
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if (n_waiting == 0)
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atomic_add(&pollStats.n_nothreads, 1);
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#if MUTEX_EPOLL
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simple_mutex_unlock(&epoll_wait_mutex);
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#endif
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#endif /* BLOCKINGPOLL */
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if (nfds > 0)
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{
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LOGIF(LD, (skygw_log_write(
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LOGFILE_DEBUG,
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"%lu [poll_waitevents] epoll_wait found %d fds",
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pthread_self(),
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nfds)));
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atomic_add(&pollStats.n_polls, 1);
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if (thread_data)
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{
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thread_data[thread_id].n_fds = nfds;
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thread_data[thread_id].cur_dcb = NULL;
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thread_data[thread_id].event = 0;
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thread_data[thread_id].state = THREAD_PROCESSING;
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}
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pollStats.n_fds[(nfds < MAXNFDS ? (nfds - 1) : MAXNFDS - 1)]++;
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load_average = (load_average * load_samples + nfds)
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/ (load_samples + 1);
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atomic_add(&load_samples, 1);
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atomic_add(&load_nfds, nfds);
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for (i = 0; i < nfds; i++)
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{
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DCB *dcb = (DCB *)events[i].data.ptr;
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__uint32_t ev = events[i].events;
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CHK_DCB(dcb);
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if (thread_data)
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{
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thread_data[thread_id].cur_dcb = dcb;
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thread_data[thread_id].event = ev;
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}
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#if defined(SS_DEBUG)
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if (dcb_fake_write_ev[dcb->fd] != 0) {
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LOGIF(LD, (skygw_log_write(
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LOGFILE_DEBUG,
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"%lu [poll_waitevents] "
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"Added fake events %d to ev %d.",
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pthread_self(),
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dcb_fake_write_ev[dcb->fd],
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ev)));
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ev |= dcb_fake_write_ev[dcb->fd];
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dcb_fake_write_ev[dcb->fd] = 0;
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}
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#endif
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ss_debug(spinlock_acquire(&dcb->dcb_initlock);)
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ss_dassert(dcb->state != DCB_STATE_ALLOC);
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ss_dassert(dcb->state != DCB_STATE_DISCONNECTED);
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ss_dassert(dcb->state != DCB_STATE_FREED);
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ss_debug(spinlock_release(&dcb->dcb_initlock);)
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LOGIF(LD, (skygw_log_write(
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LOGFILE_DEBUG,
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"%lu [poll_waitevents] event %d dcb %p "
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"role %s",
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pthread_self(),
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ev,
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dcb,
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STRDCBROLE(dcb->dcb_role))));
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if (ev & EPOLLOUT)
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{
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int eno = 0;
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eno = gw_getsockerrno(dcb->fd);
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if (eno == 0) {
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#if MUTEX_BLOCK
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simple_mutex_lock(
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&dcb->dcb_write_lock,
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true);
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ss_info_dassert(
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!dcb->dcb_write_active,
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"Write already active");
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dcb->dcb_write_active = TRUE;
|
|
atomic_add(
|
|
&pollStats.n_write,
|
|
1);
|
|
dcb->func.write_ready(dcb);
|
|
dcb->dcb_write_active = FALSE;
|
|
simple_mutex_unlock(
|
|
&dcb->dcb_write_lock);
|
|
#else
|
|
atomic_add(&pollStats.n_write,
|
|
1);
|
|
dcb_pollout(dcb, thread_id, nfds);
|
|
#endif
|
|
} else {
|
|
LOGIF(LD, (skygw_log_write(
|
|
LOGFILE_DEBUG,
|
|
"%lu [poll_waitevents] "
|
|
"EPOLLOUT due %d, %s. "
|
|
"dcb %p, fd %i",
|
|
pthread_self(),
|
|
eno,
|
|
strerror(eno),
|
|
dcb,
|
|
dcb->fd)));
|
|
}
|
|
}
|
|
if (ev & EPOLLIN)
|
|
{
|
|
#if MUTEX_BLOCK
|
|
simple_mutex_lock(&dcb->dcb_read_lock,
|
|
true);
|
|
ss_info_dassert(!dcb->dcb_read_active,
|
|
"Read already active");
|
|
dcb->dcb_read_active = TRUE;
|
|
#endif
|
|
|
|
if (dcb->state == DCB_STATE_LISTENING)
|
|
{
|
|
LOGIF(LD, (skygw_log_write(
|
|
LOGFILE_DEBUG,
|
|
"%lu [poll_waitevents] "
|
|
"Accept in fd %d",
|
|
pthread_self(),
|
|
dcb->fd)));
|
|
atomic_add(
|
|
&pollStats.n_accept, 1);
|
|
dcb->func.accept(dcb);
|
|
}
|
|
else
|
|
{
|
|
LOGIF(LD, (skygw_log_write(
|
|
LOGFILE_DEBUG,
|
|
"%lu [poll_waitevents] "
|
|
"Read in dcb %p fd %d",
|
|
pthread_self(),
|
|
dcb,
|
|
dcb->fd)));
|
|
atomic_add(&pollStats.n_read, 1);
|
|
#if MUTEX_BLOCK
|
|
dcb->func.read(dcb);
|
|
#else
|
|
dcb_pollin(dcb, thread_id, nfds);
|
|
#endif
|
|
}
|
|
#if MUTEX_BLOCK
|
|
dcb->dcb_read_active = FALSE;
|
|
simple_mutex_unlock(
|
|
&dcb->dcb_read_lock);
|
|
#endif
|
|
}
|
|
if (ev & EPOLLERR)
|
|
{
|
|
int eno = gw_getsockerrno(dcb->fd);
|
|
#if defined(SS_DEBUG)
|
|
if (eno == 0) {
|
|
eno = dcb_fake_write_errno[dcb->fd];
|
|
LOGIF(LD, (skygw_log_write(
|
|
LOGFILE_DEBUG,
|
|
"%lu [poll_waitevents] "
|
|
"Added fake errno %d. "
|
|
"%s",
|
|
pthread_self(),
|
|
eno,
|
|
strerror(eno))));
|
|
}
|
|
dcb_fake_write_errno[dcb->fd] = 0;
|
|
#endif
|
|
if (eno != 0) {
|
|
LOGIF(LD, (skygw_log_write(
|
|
LOGFILE_DEBUG,
|
|
"%lu [poll_waitevents] "
|
|
"EPOLLERR due %d, %s.",
|
|
pthread_self(),
|
|
eno,
|
|
strerror(eno))));
|
|
}
|
|
atomic_add(&pollStats.n_error, 1);
|
|
dcb->func.error(dcb);
|
|
}
|
|
|
|
if (ev & EPOLLHUP)
|
|
{
|
|
int eno = 0;
|
|
eno = gw_getsockerrno(dcb->fd);
|
|
|
|
LOGIF(LD, (skygw_log_write(
|
|
LOGFILE_DEBUG,
|
|
"%lu [poll_waitevents] "
|
|
"EPOLLHUP on dcb %p, fd %d. "
|
|
"Errno %d, %s.",
|
|
pthread_self(),
|
|
dcb,
|
|
dcb->fd,
|
|
eno,
|
|
strerror(eno))));
|
|
atomic_add(&pollStats.n_hup, 1);
|
|
spinlock_acquire(&dcb->dcb_initlock);
|
|
if ((dcb->flags & DCBF_HUNG) == 0)
|
|
{
|
|
dcb->flags |= DCBF_HUNG;
|
|
spinlock_release(&dcb->dcb_initlock);
|
|
dcb->func.hangup(dcb);
|
|
}
|
|
else
|
|
spinlock_release(&dcb->dcb_initlock);
|
|
}
|
|
|
|
#ifdef EPOLLRDHUP
|
|
if (ev & EPOLLRDHUP)
|
|
{
|
|
int eno = 0;
|
|
eno = gw_getsockerrno(dcb->fd);
|
|
|
|
LOGIF(LD, (skygw_log_write(
|
|
LOGFILE_DEBUG,
|
|
"%lu [poll_waitevents] "
|
|
"EPOLLRDHUP on dcb %p, fd %d. "
|
|
"Errno %d, %s.",
|
|
pthread_self(),
|
|
dcb,
|
|
dcb->fd,
|
|
eno,
|
|
strerror(eno))));
|
|
atomic_add(&pollStats.n_hup, 1);
|
|
spinlock_acquire(&dcb->dcb_initlock);
|
|
if ((dcb->flags & DCBF_HUNG) == 0)
|
|
{
|
|
dcb->flags |= DCBF_HUNG;
|
|
spinlock_release(&dcb->dcb_initlock);
|
|
dcb->func.hangup(dcb);
|
|
}
|
|
else
|
|
spinlock_release(&dcb->dcb_initlock);
|
|
}
|
|
#endif
|
|
} /*< for */
|
|
no_op = FALSE;
|
|
} /*< if (nfds > 0) */
|
|
process_zombies:
|
|
if (thread_data)
|
|
{
|
|
thread_data[thread_id].state = THREAD_ZPROCESSING;
|
|
}
|
|
zombies = dcb_process_zombies(thread_id, NULL);
|
|
|
|
if (zombies == NULL) {
|
|
process_zombies_only = false;
|
|
}
|
|
|
|
if (do_shutdown)
|
|
{
|
|
/*<
|
|
* Remove the thread from the bitmask of running
|
|
* polling threads.
|
|
*/
|
|
if (thread_data)
|
|
{
|
|
thread_data[thread_id].state = THREAD_STOPPED;
|
|
}
|
|
bitmask_clear(&poll_mask, thread_id);
|
|
/** Release mysql thread context */
|
|
mysql_thread_end();
|
|
return;
|
|
}
|
|
if (thread_data)
|
|
{
|
|
thread_data[thread_id].state = THREAD_IDLE;
|
|
}
|
|
} /*< while(1) */
|
|
}
|
|
|
|
/**
|
|
* Shutdown the polling loop
|
|
*/
|
|
void
|
|
poll_shutdown()
|
|
{
|
|
do_shutdown = 1;
|
|
}
|
|
|
|
/**
|
|
* Return the bitmask of polling threads
|
|
*
|
|
* @return The bitmask of the running polling threads
|
|
*/
|
|
GWBITMASK *
|
|
poll_bitmask()
|
|
{
|
|
return &poll_mask;
|
|
}
|
|
|
|
/**
|
|
* Debug routine to print the polling statistics
|
|
*
|
|
* @param dcb DCB to print to
|
|
*/
|
|
void
|
|
dprintPollStats(DCB *dcb)
|
|
{
|
|
int i;
|
|
|
|
dcb_printf(dcb, "Number of epoll cycles: %d\n",
|
|
pollStats.n_polls);
|
|
dcb_printf(dcb, "Number of read events: %d\n",
|
|
pollStats.n_read);
|
|
dcb_printf(dcb, "Number of write events: %d\n",
|
|
pollStats.n_write);
|
|
dcb_printf(dcb, "Number of error events: %d\n",
|
|
pollStats.n_error);
|
|
dcb_printf(dcb, "Number of hangup events: %d\n",
|
|
pollStats.n_hup);
|
|
dcb_printf(dcb, "Number of accept events: %d\n",
|
|
pollStats.n_accept);
|
|
dcb_printf(dcb, "Number of times no threads polling: %d\n",
|
|
pollStats.n_nothreads);
|
|
|
|
dcb_printf(dcb, "No of poll completions with descriptors\n");
|
|
dcb_printf(dcb, "\tNo. of descriptors\tNo. of poll completions.\n");
|
|
for (i = 0; i < MAXNFDS - 1; i++)
|
|
{
|
|
dcb_printf(dcb, "\t%2d\t\t\t%d\n", i + 1, pollStats.n_fds[i]);
|
|
}
|
|
dcb_printf(dcb, "\t>= %d\t\t\t%d\n", MAXNFDS,
|
|
pollStats.n_fds[MAXNFDS-1]);
|
|
}
|
|
|
|
/**
|
|
* Convert an EPOLL event mask into a printable string
|
|
*
|
|
* @param event The event mask
|
|
* @return A string representation, the caller must free the string
|
|
*/
|
|
static char *
|
|
event_to_string(uint32_t event)
|
|
{
|
|
char *str;
|
|
|
|
str = malloc(22); // 22 is max returned string length
|
|
if (str == NULL)
|
|
return NULL;
|
|
*str = 0;
|
|
if (event & EPOLLIN)
|
|
{
|
|
strcat(str, "IN");
|
|
}
|
|
if (event & EPOLLOUT)
|
|
{
|
|
if (*str)
|
|
strcat(str, "|");
|
|
strcat(str, "OUT");
|
|
}
|
|
if (event & EPOLLERR)
|
|
{
|
|
if (*str)
|
|
strcat(str, "|");
|
|
strcat(str, "ERR");
|
|
}
|
|
if (event & EPOLLHUP)
|
|
{
|
|
if (*str)
|
|
strcat(str, "|");
|
|
strcat(str, "HUP");
|
|
}
|
|
#ifdef EPOLLRDHUP
|
|
if (event & EPOLLRDHUP)
|
|
{
|
|
if (*str)
|
|
strcat(str, "|");
|
|
strcat(str, "RDHUP");
|
|
}
|
|
#endif
|
|
|
|
return str;
|
|
}
|
|
|
|
/**
|
|
* Print the thread status for all the polling threads
|
|
*
|
|
* @param dcb The DCB to send the thread status data
|
|
*/
|
|
void
|
|
dShowThreads(DCB *dcb)
|
|
{
|
|
int i, j, n;
|
|
char *state;
|
|
double avg1 = 0.0, avg5 = 0.0, avg15 = 0.0;
|
|
|
|
|
|
dcb_printf(dcb, "Polling Threads.\n\n");
|
|
dcb_printf(dcb, "Historic Thread Load Average: %.2f.\n", load_average);
|
|
dcb_printf(dcb, "Current Thread Load Average: %.2f.\n", current_avg);
|
|
|
|
/* Average all the samples to get the 15 minute average */
|
|
for (i = 0; i < n_avg_samples; i++)
|
|
avg15 += avg_samples[i];
|
|
avg15 = avg15 / n_avg_samples;
|
|
|
|
/* Average the last third of the samples to get the 5 minute average */
|
|
n = 5 * 60 / POLL_LOAD_FREQ;
|
|
i = next_sample - (n + 1);
|
|
if (i < 0)
|
|
i += n_avg_samples;
|
|
for (j = i; j < i + n; j++)
|
|
avg5 += avg_samples[j % n_avg_samples];
|
|
avg5 = (3 * avg5) / (n_avg_samples);
|
|
|
|
/* Average the last 15th of the samples to get the 1 minute average */
|
|
n = 60 / POLL_LOAD_FREQ;
|
|
i = next_sample - (n + 1);
|
|
if (i < 0)
|
|
i += n_avg_samples;
|
|
for (j = i; j < i + n; j++)
|
|
avg1 += avg_samples[j % n_avg_samples];
|
|
avg1 = (15 * avg1) / (n_avg_samples);
|
|
|
|
dcb_printf(dcb, "15 Minute Average: %.2f, 5 Minute Average: %.2f, "
|
|
"1 Minute Average: %.2f\n\n", avg15, avg5, avg1);
|
|
|
|
if (thread_data == NULL)
|
|
return;
|
|
dcb_printf(dcb, " ID | State | # fds | Descriptor | Event\n");
|
|
dcb_printf(dcb, "----+------------+--------+------------------+---------------\n");
|
|
for (i = 0; i < n_threads; i++)
|
|
{
|
|
switch (thread_data[i].state)
|
|
{
|
|
case THREAD_STOPPED:
|
|
state = "Stopped";
|
|
break;
|
|
case THREAD_IDLE:
|
|
state = "Idle";
|
|
break;
|
|
case THREAD_POLLING:
|
|
state = "Polling";
|
|
break;
|
|
case THREAD_PROCESSING:
|
|
state = "Processing";
|
|
break;
|
|
case THREAD_ZPROCESSING:
|
|
state = "Collecting";
|
|
break;
|
|
}
|
|
if (thread_data[i].state != THREAD_PROCESSING)
|
|
dcb_printf(dcb,
|
|
" %2d | %-10s | | |\n",
|
|
i, state);
|
|
else if (thread_data[i].cur_dcb == NULL)
|
|
dcb_printf(dcb,
|
|
" %2d | %-10s | %6d | |\n",
|
|
i, state, thread_data[i].n_fds);
|
|
else
|
|
{
|
|
char *event_string
|
|
= event_to_string(thread_data[i].event);
|
|
if (event_string == NULL)
|
|
event_string = "??";
|
|
dcb_printf(dcb,
|
|
" %2d | %-10s | %6d | %-16p | %s\n",
|
|
i, state, thread_data[i].n_fds,
|
|
thread_data[i].cur_dcb, event_string);
|
|
free(event_string);
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* The function used to calculate time based load data. This is called by the
|
|
* housekeeper every POLL_LOAD_FREQ seconds.
|
|
*
|
|
* @param data Argument required by the housekeeper but not used here
|
|
*/
|
|
static void
|
|
poll_loadav(void *data)
|
|
{
|
|
static int last_samples = 0, last_nfds = 0;
|
|
int new_samples, new_nfds;
|
|
|
|
new_samples = load_samples - last_samples;
|
|
new_nfds = load_nfds - last_nfds;
|
|
last_samples = load_samples;
|
|
last_nfds = load_nfds;
|
|
|
|
/* POLL_LOAD_FREQ average is... */
|
|
if (new_samples)
|
|
current_avg = new_nfds / new_samples;
|
|
else
|
|
current_avg = 0.0;
|
|
avg_samples[next_sample] = current_avg;
|
|
next_sample++;
|
|
if (next_sample >= n_avg_samples)
|
|
next_sample = 0;
|
|
}
|