sync.c

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/*
 * Copyright (c) 2009-2012 Red Hat, Inc.
 *
 * All rights reserved.
 *
 * Author: Steven Dake (sdake@redhat.com)
 *
 * This software licensed under BSD license, the text of which follows:
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * - Redistributions of source code must retain the above copyright notice,
 *   this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright notice,
 *   this list of conditions and the following disclaimer in the documentation
 *   and/or other materials provided with the distribution.
 * - Neither the name of the MontaVista Software, Inc. nor the names of its
 *   contributors may be used to endorse or promote products derived from this
 *   software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */
#include <config.h>
 
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/ioctl.h>
#include <netinet/in.h>
#include <sys/uio.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <time.h>
#include <arpa/inet.h>
 
#include <corosync/corotypes.h>
#include <corosync/swab.h>
#include <corosync/totem/totempg.h>
#include <corosync/totem/totem.h>
#include <corosync/logsys.h>
#include <qb/qbipc_common.h>
#include "schedwrk.h"
#include "quorum.h"
#include "sync.h"
#include "main.h"
 
LOGSYS_DECLARE_SUBSYS ("SYNC");
 
#define MESSAGE_REQ_SYNC_BARRIER 0
#define MESSAGE_REQ_SYNC_SERVICE_BUILD 1
 
enum sync_process_state {
        PROCESS,
        ACTIVATE
};
 
enum sync_state {
        SYNC_SERVICELIST_BUILD,
        SYNC_PROCESS,
        SYNC_BARRIER
};
 
struct service_entry {
        int service_id;
        void (*sync_init) (
                const unsigned int *trans_list,
                size_t trans_list_entries,
                const unsigned int *member_list,
                size_t member_list_entries,
                const struct memb_ring_id *ring_id);
        void (*sync_abort) (void);
        int (*sync_process) (void);
        void (*sync_activate) (void);
        enum sync_process_state state;
        char name[128];
};
 
struct processor_entry {
        int nodeid;
        int received;
};
 
struct req_exec_service_build_message {
        struct qb_ipc_request_header header __attribute__((aligned(8)));
        struct memb_ring_id ring_id __attribute__((aligned(8)));
        int service_list_entries __attribute__((aligned(8)));
        int service_list[128] __attribute__((aligned(8)));
};
 
struct req_exec_barrier_message {
        struct qb_ipc_request_header header __attribute__((aligned(8)));
        struct memb_ring_id ring_id __attribute__((aligned(8)));
};
 
static enum sync_state my_state = SYNC_BARRIER;
 
static struct memb_ring_id my_ring_id;
 
static int my_processing_idx = 0;
 
static hdb_handle_t my_schedwrk_handle;
 
static struct processor_entry my_processor_list[PROCESSOR_COUNT_MAX];
 
static unsigned int my_member_list[PROCESSOR_COUNT_MAX];
 
static unsigned int my_trans_list[PROCESSOR_COUNT_MAX];
 
static size_t my_member_list_entries = 0;
 
static size_t my_trans_list_entries = 0;
 
static int my_processor_list_entries = 0;
 
static struct service_entry my_service_list[SERVICES_COUNT_MAX];
 
static int my_service_list_entries = 0;
 
static void (*sync_synchronization_completed) (void);
 
static void sync_deliver_fn (
        unsigned int nodeid,
        const void *msg,
        unsigned int msg_len,
        int endian_conversion_required);
 
static int schedwrk_processor (const void *context);
 
static void sync_process_enter (void);
 
static void sync_process_call_init (void);
 
static struct totempg_group sync_group = {
    .group      = "sync",
    .group_len  = 4
};
 
static void *sync_group_handle;
 
int (*my_sync_callbacks_retrieve) (
                int service_id,
                struct sync_callbacks *callbacks);
 
int sync_init (
        int (*sync_callbacks_retrieve) (
                int service_id,
                struct sync_callbacks *callbacks),
        void (*synchronization_completed) (void))
{
        unsigned int res;
 
        res = totempg_groups_initialize (
                &sync_group_handle,
                sync_deliver_fn,
                NULL);
        if (res == -1) {
                log_printf (LOGSYS_LEVEL_ERROR,
                        "Couldn't initialize groups interface.");
                return (-1);
        }
 
        res = totempg_groups_join (
                sync_group_handle,
                &sync_group,
                1);
        if (res == -1) {
                log_printf (LOGSYS_LEVEL_ERROR, "Couldn't join group.");
                return (-1);
        }
 
        sync_synchronization_completed = synchronization_completed;
        my_sync_callbacks_retrieve = sync_callbacks_retrieve;
 
        return (0);
}
 
static void sync_barrier_handler (unsigned int nodeid, const void *msg)
{
        const struct req_exec_barrier_message *req_exec_barrier_message = msg;
        int i;
        int barrier_reached = 1;
 
        if (memcmp (&my_ring_id, &req_exec_barrier_message->ring_id,
                sizeof (struct memb_ring_id)) != 0) {
 
                log_printf (LOGSYS_LEVEL_DEBUG, "barrier for old ring - discarding");
                return;
        }
        for (i = 0; i < my_processor_list_entries; i++) {
                if (my_processor_list[i].nodeid == nodeid) {
                        my_processor_list[i].received = 1;
                }
        }
        for (i = 0; i < my_processor_list_entries; i++) {
                if (my_processor_list[i].received == 0) {
                        barrier_reached = 0;
                }
        }
        if (barrier_reached) {
                log_printf (LOGSYS_LEVEL_DEBUG, "Committing synchronization for %s",
                        my_service_list[my_processing_idx].name);
                my_service_list[my_processing_idx].state = ACTIVATE;
 
                if (my_sync_callbacks_retrieve(my_service_list[my_processing_idx].service_id, NULL) != -1) {
                        my_service_list[my_processing_idx].sync_activate ();
                }
 
                my_processing_idx += 1;
                if (my_service_list_entries == my_processing_idx) {
                        sync_synchronization_completed ();
                } else {
                        sync_process_enter ();
                }
        }
}
 
static void dummy_sync_abort (void)
{
}
 
static int dummy_sync_process (void)
{
        return (0);
}
 
static void dummy_sync_activate (void)
{
}
 
static int service_entry_compare (const void *a, const void *b)
{
        const struct service_entry *service_entry_a = a;
        const struct service_entry *service_entry_b = b;
 
        return (service_entry_a->service_id > service_entry_b->service_id);
}
 
static void sync_service_build_handler (unsigned int nodeid, const void *msg)
{
        const struct req_exec_service_build_message *req_exec_service_build_message = msg;
        int i, j;
        int barrier_reached = 1;
        int found;
        int qsort_trigger = 0;
 
        if (memcmp (&my_ring_id, &req_exec_service_build_message->ring_id,
                sizeof (struct memb_ring_id)) != 0) {
                log_printf (LOGSYS_LEVEL_DEBUG, "service build for old ring - discarding");
                return;
        }
        for (i = 0; i < req_exec_service_build_message->service_list_entries; i++) {
 
                found = 0;
                for (j = 0; j < my_service_list_entries; j++) {
                        if (req_exec_service_build_message->service_list[i] ==
                                my_service_list[j].service_id) {
                                found = 1;
                                break;
                        }
                }
                if (found == 0) {
                        my_service_list[my_service_list_entries].state = PROCESS;
                        my_service_list[my_service_list_entries].service_id =
                                req_exec_service_build_message->service_list[i];
                        sprintf (my_service_list[my_service_list_entries].name,
                                "Unknown External Service (id = %d)\n",
                                req_exec_service_build_message->service_list[i]);
                        my_service_list[my_service_list_entries].sync_init =
                                NULL;
                        my_service_list[my_service_list_entries].sync_abort =
                                dummy_sync_abort;
                        my_service_list[my_service_list_entries].sync_process =
                                dummy_sync_process;
                        my_service_list[my_service_list_entries].sync_activate =
                                dummy_sync_activate;
                        my_service_list_entries += 1;
 
                        qsort_trigger = 1;
                }
        }
        if (qsort_trigger) {
                qsort (my_service_list, my_service_list_entries,
                        sizeof (struct service_entry), service_entry_compare);
        }
        for (i = 0; i < my_processor_list_entries; i++) {
                if (my_processor_list[i].nodeid == nodeid) {
                        my_processor_list[i].received = 1;
                }
        }
        for (i = 0; i < my_processor_list_entries; i++) {
                if (my_processor_list[i].received == 0) {
                        barrier_reached = 0;
                }
        }
        if (barrier_reached) {
                log_printf (LOGSYS_LEVEL_DEBUG, "enter sync process");
                sync_process_enter ();
        }
}
 
static void sync_deliver_fn (
        unsigned int nodeid,
        const void *msg,
        unsigned int msg_len,
        int endian_conversion_required)
{
        struct qb_ipc_request_header *header = (struct qb_ipc_request_header *)msg;
 
        switch (header->id) {
                case MESSAGE_REQ_SYNC_BARRIER:
                        sync_barrier_handler (nodeid, msg);
                        break;
                case MESSAGE_REQ_SYNC_SERVICE_BUILD:
                        sync_service_build_handler (nodeid, msg);
                        break;
        }
}
 
static void barrier_message_transmit (void)
{
        struct iovec iovec;
        struct req_exec_barrier_message req_exec_barrier_message;
 
        memset(&req_exec_barrier_message, 0, sizeof(req_exec_barrier_message));
 
        req_exec_barrier_message.header.size = sizeof (struct req_exec_barrier_message);
        req_exec_barrier_message.header.id = MESSAGE_REQ_SYNC_BARRIER;
 
        memcpy (&req_exec_barrier_message.ring_id, &my_ring_id,
                sizeof (struct memb_ring_id));
 
        iovec.iov_base = (char *)&req_exec_barrier_message;
        iovec.iov_len = sizeof (req_exec_barrier_message);
 
        (void)totempg_groups_mcast_joined (sync_group_handle,
                &iovec, 1, TOTEMPG_AGREED);
}
 
static void service_build_message_transmit (struct req_exec_service_build_message *service_build_message)
{
        struct iovec iovec;
 
        service_build_message->header.size = sizeof (struct req_exec_service_build_message);
        service_build_message->header.id = MESSAGE_REQ_SYNC_SERVICE_BUILD;
 
        memcpy (&service_build_message->ring_id, &my_ring_id,
                sizeof (struct memb_ring_id));
 
        iovec.iov_base = (void *)service_build_message;
        iovec.iov_len = sizeof (struct req_exec_service_build_message);
 
        (void)totempg_groups_mcast_joined (sync_group_handle,
                &iovec, 1, TOTEMPG_AGREED);
}
 
static void sync_barrier_enter (void)
{
        my_state = SYNC_BARRIER;
        barrier_message_transmit ();
}
 
static void sync_process_call_init (void)
{
        unsigned int old_trans_list[PROCESSOR_COUNT_MAX];
        size_t old_trans_list_entries = 0;
        int o, m;
        int i;
 
        memcpy (old_trans_list, my_trans_list, my_trans_list_entries *
                sizeof (unsigned int));
        old_trans_list_entries = my_trans_list_entries;
 
        my_trans_list_entries = 0;
        for (o = 0; o < old_trans_list_entries; o++) {
                for (m = 0; m < my_member_list_entries; m++) {
                        if (old_trans_list[o] == my_member_list[m]) {
                                my_trans_list[my_trans_list_entries] = my_member_list[m];
                                my_trans_list_entries++;
                                break;
                        }
                }
        }
 
        for (i = 0; i < my_service_list_entries; i++) {
                if (my_sync_callbacks_retrieve(my_service_list[i].service_id, NULL) != -1) {
                        my_service_list[i].sync_init (my_trans_list,
                                my_trans_list_entries, my_member_list,
                                my_member_list_entries,
                                &my_ring_id);
                }
        }
}
 
static void sync_process_enter (void)
{
        int i;
 
        my_state = SYNC_PROCESS;
 
        /*
         * No sync services
         */
        if (my_service_list_entries == 0) {
                my_state = SYNC_SERVICELIST_BUILD;
                sync_synchronization_completed ();
                return;
        }
        for (i = 0; i < my_processor_list_entries; i++) {
                my_processor_list[i].received = 0;
        }
 
        schedwrk_create (&my_schedwrk_handle,
                schedwrk_processor,
                NULL);
}
 
static void sync_servicelist_build_enter (
        const unsigned int *member_list,
        size_t member_list_entries,
        const struct memb_ring_id *ring_id)
{
        struct req_exec_service_build_message service_build;
        int i;
        int res;
        struct sync_callbacks sync_callbacks;
 
        memset(&service_build, 0, sizeof(service_build));
 
        my_state = SYNC_SERVICELIST_BUILD;
        for (i = 0; i < member_list_entries; i++) {
                my_processor_list[i].nodeid = member_list[i];
                my_processor_list[i].received = 0;
        }
        my_processor_list_entries = member_list_entries;
 
        memcpy (my_member_list, member_list,
                member_list_entries * sizeof (unsigned int));
        my_member_list_entries = member_list_entries;
 
        my_processing_idx = 0;
 
        memset(my_service_list, 0, sizeof (struct service_entry) * SERVICES_COUNT_MAX);
        my_service_list_entries = 0;
 
        for (i = 0; i < SERVICES_COUNT_MAX; i++) {
                res = my_sync_callbacks_retrieve (i, &sync_callbacks);
                if (res == -1) {
                        continue;
                }
                if (sync_callbacks.sync_init == NULL) {
                        continue;
                }
                my_service_list[my_service_list_entries].state = PROCESS;
                my_service_list[my_service_list_entries].service_id = i;
 
                assert(strlen(sync_callbacks.name) < sizeof(my_service_list[my_service_list_entries].name));
 
                strcpy (my_service_list[my_service_list_entries].name,
                        sync_callbacks.name);
                my_service_list[my_service_list_entries].sync_init = sync_callbacks.sync_init;
                my_service_list[my_service_list_entries].sync_process = sync_callbacks.sync_process;
                my_service_list[my_service_list_entries].sync_abort = sync_callbacks.sync_abort;
                my_service_list[my_service_list_entries].sync_activate = sync_callbacks.sync_activate;
                my_service_list_entries += 1;
        }
 
        for (i = 0; i < my_service_list_entries; i++) {
                service_build.service_list[i] =
                        my_service_list[i].service_id;
        }
        service_build.service_list_entries = my_service_list_entries;
 
        service_build_message_transmit (&service_build);
 
        log_printf (LOGSYS_LEVEL_DEBUG, "call init for locally known services");
        sync_process_call_init ();
}
 
static int schedwrk_processor (const void *context)
{
        int res = 0;
 
        if (my_service_list[my_processing_idx].state == PROCESS) {
                if (my_sync_callbacks_retrieve(my_service_list[my_processing_idx].service_id, NULL) != -1) {
                        res = my_service_list[my_processing_idx].sync_process ();
                } else {
                        res = 0;
                }
                if (res == 0) {
                        sync_barrier_enter();
                } else {
                        return (-1);
                }
        }
        return (0);
}
 
void sync_start (
        const unsigned int *member_list,
        size_t member_list_entries,
        const struct memb_ring_id *ring_id)
{
        ENTER();
        memcpy (&my_ring_id, ring_id, sizeof (struct memb_ring_id));
 
        sync_servicelist_build_enter (member_list, member_list_entries,
                ring_id);
}
 
void sync_save_transitional (
        const unsigned int *member_list,
        size_t member_list_entries,
        const struct memb_ring_id *ring_id)
{
        ENTER();
        memcpy (my_trans_list, member_list, member_list_entries *
                sizeof (unsigned int));
        my_trans_list_entries = member_list_entries;
}
 
void sync_abort (void)
{
        ENTER();
        if (my_state == SYNC_PROCESS) {
                schedwrk_destroy (my_schedwrk_handle);
                if (my_sync_callbacks_retrieve(my_service_list[my_processing_idx].service_id, NULL) != -1) {
                        my_service_list[my_processing_idx].sync_abort ();
                }
        }
 
        /* this will cause any "old" barrier messages from causing
         * problems.
         */
        memset (&my_ring_id, 0, sizeof (struct memb_ring_id));
}