qemu-e2k/net/colo-compare.c
Markus Armbruster 668f62ec62 error: Eliminate error_propagate() with Coccinelle, part 1
When all we do with an Error we receive into a local variable is
propagating to somewhere else, we can just as well receive it there
right away.  Convert

    if (!foo(..., &err)) {
        ...
        error_propagate(errp, err);
        ...
        return ...
    }

to

    if (!foo(..., errp)) {
        ...
        ...
        return ...
    }

where nothing else needs @err.  Coccinelle script:

    @rule1 forall@
    identifier fun, err, errp, lbl;
    expression list args, args2;
    binary operator op;
    constant c1, c2;
    symbol false;
    @@
         if (
    (
    -        fun(args, &err, args2)
    +        fun(args, errp, args2)
    |
    -        !fun(args, &err, args2)
    +        !fun(args, errp, args2)
    |
    -        fun(args, &err, args2) op c1
    +        fun(args, errp, args2) op c1
    )
            )
         {
             ... when != err
                 when != lbl:
                 when strict
    -        error_propagate(errp, err);
             ... when != err
    (
             return;
    |
             return c2;
    |
             return false;
    )
         }

    @rule2 forall@
    identifier fun, err, errp, lbl;
    expression list args, args2;
    expression var;
    binary operator op;
    constant c1, c2;
    symbol false;
    @@
    -    var = fun(args, &err, args2);
    +    var = fun(args, errp, args2);
         ... when != err
         if (
    (
             var
    |
             !var
    |
             var op c1
    )
            )
         {
             ... when != err
                 when != lbl:
                 when strict
    -        error_propagate(errp, err);
             ... when != err
    (
             return;
    |
             return c2;
    |
             return false;
    |
             return var;
    )
         }

    @depends on rule1 || rule2@
    identifier err;
    @@
    -    Error *err = NULL;
         ... when != err

Not exactly elegant, I'm afraid.

The "when != lbl:" is necessary to avoid transforming

         if (fun(args, &err)) {
             goto out
         }
         ...
     out:
         error_propagate(errp, err);

even though other paths to label out still need the error_propagate().
For an actual example, see sclp_realize().

Without the "when strict", Coccinelle transforms vfio_msix_setup(),
incorrectly.  I don't know what exactly "when strict" does, only that
it helps here.

The match of return is narrower than what I want, but I can't figure
out how to express "return where the operand doesn't use @err".  For
an example where it's too narrow, see vfio_intx_enable().

Silently fails to convert hw/arm/armsse.c, because Coccinelle gets
confused by ARMSSE being used both as typedef and function-like macro
there.  Converted manually.

Line breaks tidied up manually.  One nested declaration of @local_err
deleted manually.  Preexisting unwanted blank line dropped in
hw/riscv/sifive_e.c.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200707160613.848843-35-armbru@redhat.com>
2020-07-10 15:18:08 +02:00

1468 lines
44 KiB
C

/*
* COarse-grain LOck-stepping Virtual Machines for Non-stop Service (COLO)
* (a.k.a. Fault Tolerance or Continuous Replication)
*
* Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD.
* Copyright (c) 2016 FUJITSU LIMITED
* Copyright (c) 2016 Intel Corporation
*
* Author: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or
* later. See the COPYING file in the top-level directory.
*/
#include "qemu/osdep.h"
#include "qemu-common.h"
#include "qemu/error-report.h"
#include "trace.h"
#include "qapi/error.h"
#include "net/net.h"
#include "net/eth.h"
#include "qom/object_interfaces.h"
#include "qemu/iov.h"
#include "qom/object.h"
#include "net/queue.h"
#include "chardev/char-fe.h"
#include "qemu/sockets.h"
#include "colo.h"
#include "sysemu/iothread.h"
#include "net/colo-compare.h"
#include "migration/colo.h"
#include "migration/migration.h"
#include "util.h"
#include "block/aio-wait.h"
#include "qemu/coroutine.h"
#define TYPE_COLO_COMPARE "colo-compare"
#define COLO_COMPARE(obj) \
OBJECT_CHECK(CompareState, (obj), TYPE_COLO_COMPARE)
static QTAILQ_HEAD(, CompareState) net_compares =
QTAILQ_HEAD_INITIALIZER(net_compares);
static NotifierList colo_compare_notifiers =
NOTIFIER_LIST_INITIALIZER(colo_compare_notifiers);
#define COMPARE_READ_LEN_MAX NET_BUFSIZE
#define MAX_QUEUE_SIZE 1024
#define COLO_COMPARE_FREE_PRIMARY 0x01
#define COLO_COMPARE_FREE_SECONDARY 0x02
#define REGULAR_PACKET_CHECK_MS 3000
#define DEFAULT_TIME_OUT_MS 3000
static QemuMutex colo_compare_mutex;
static bool colo_compare_active;
static QemuMutex event_mtx;
static QemuCond event_complete_cond;
static int event_unhandled_count;
/*
* + CompareState ++
* | |
* +---------------+ +---------------+ +---------------+
* | conn list + - > conn + ------- > conn + -- > ......
* +---------------+ +---------------+ +---------------+
* | | | | | |
* +---------------+ +---v----+ +---v----+ +---v----+ +---v----+
* |primary | |secondary |primary | |secondary
* |packet | |packet + |packet | |packet +
* +--------+ +--------+ +--------+ +--------+
* | | | |
* +---v----+ +---v----+ +---v----+ +---v----+
* |primary | |secondary |primary | |secondary
* |packet | |packet + |packet | |packet +
* +--------+ +--------+ +--------+ +--------+
* | | | |
* +---v----+ +---v----+ +---v----+ +---v----+
* |primary | |secondary |primary | |secondary
* |packet | |packet + |packet | |packet +
* +--------+ +--------+ +--------+ +--------+
*/
typedef struct SendCo {
Coroutine *co;
struct CompareState *s;
CharBackend *chr;
GQueue send_list;
bool notify_remote_frame;
bool done;
int ret;
} SendCo;
typedef struct SendEntry {
uint32_t size;
uint32_t vnet_hdr_len;
uint8_t *buf;
} SendEntry;
typedef struct CompareState {
Object parent;
char *pri_indev;
char *sec_indev;
char *outdev;
char *notify_dev;
CharBackend chr_pri_in;
CharBackend chr_sec_in;
CharBackend chr_out;
CharBackend chr_notify_dev;
SocketReadState pri_rs;
SocketReadState sec_rs;
SocketReadState notify_rs;
SendCo out_sendco;
SendCo notify_sendco;
bool vnet_hdr;
uint32_t compare_timeout;
uint32_t expired_scan_cycle;
/*
* Record the connection that through the NIC
* Element type: Connection
*/
GQueue conn_list;
/* Record the connection without repetition */
GHashTable *connection_track_table;
IOThread *iothread;
GMainContext *worker_context;
QEMUTimer *packet_check_timer;
QEMUBH *event_bh;
enum colo_event event;
QTAILQ_ENTRY(CompareState) next;
} CompareState;
typedef struct CompareClass {
ObjectClass parent_class;
} CompareClass;
enum {
PRIMARY_IN = 0,
SECONDARY_IN,
};
static const char *colo_mode[] = {
[PRIMARY_IN] = "primary",
[SECONDARY_IN] = "secondary",
};
static int compare_chr_send(CompareState *s,
uint8_t *buf,
uint32_t size,
uint32_t vnet_hdr_len,
bool notify_remote_frame,
bool zero_copy);
static bool packet_matches_str(const char *str,
const uint8_t *buf,
uint32_t packet_len)
{
if (packet_len != strlen(str)) {
return false;
}
return !memcmp(str, buf, strlen(str));
}
static void notify_remote_frame(CompareState *s)
{
char msg[] = "DO_CHECKPOINT";
int ret = 0;
ret = compare_chr_send(s, (uint8_t *)msg, strlen(msg), 0, true, false);
if (ret < 0) {
error_report("Notify Xen COLO-frame failed");
}
}
static void colo_compare_inconsistency_notify(CompareState *s)
{
if (s->notify_dev) {
notify_remote_frame(s);
} else {
notifier_list_notify(&colo_compare_notifiers,
migrate_get_current());
}
}
static gint seq_sorter(Packet *a, Packet *b, gpointer data)
{
struct tcp_hdr *atcp, *btcp;
atcp = (struct tcp_hdr *)(a->transport_header);
btcp = (struct tcp_hdr *)(b->transport_header);
return ntohl(atcp->th_seq) - ntohl(btcp->th_seq);
}
static void fill_pkt_tcp_info(void *data, uint32_t *max_ack)
{
Packet *pkt = data;
struct tcp_hdr *tcphd;
tcphd = (struct tcp_hdr *)pkt->transport_header;
pkt->tcp_seq = ntohl(tcphd->th_seq);
pkt->tcp_ack = ntohl(tcphd->th_ack);
*max_ack = *max_ack > pkt->tcp_ack ? *max_ack : pkt->tcp_ack;
pkt->header_size = pkt->transport_header - (uint8_t *)pkt->data
+ (tcphd->th_off << 2) - pkt->vnet_hdr_len;
pkt->payload_size = pkt->size - pkt->header_size;
pkt->seq_end = pkt->tcp_seq + pkt->payload_size;
pkt->flags = tcphd->th_flags;
}
/*
* Return 1 on success, if return 0 means the
* packet will be dropped
*/
static int colo_insert_packet(GQueue *queue, Packet *pkt, uint32_t *max_ack)
{
if (g_queue_get_length(queue) <= MAX_QUEUE_SIZE) {
if (pkt->ip->ip_p == IPPROTO_TCP) {
fill_pkt_tcp_info(pkt, max_ack);
g_queue_insert_sorted(queue,
pkt,
(GCompareDataFunc)seq_sorter,
NULL);
} else {
g_queue_push_tail(queue, pkt);
}
return 1;
}
return 0;
}
/*
* Return 0 on success, if return -1 means the pkt
* is unsupported(arp and ipv6) and will be sent later
*/
static int packet_enqueue(CompareState *s, int mode, Connection **con)
{
ConnectionKey key;
Packet *pkt = NULL;
Connection *conn;
int ret;
if (mode == PRIMARY_IN) {
pkt = packet_new(s->pri_rs.buf,
s->pri_rs.packet_len,
s->pri_rs.vnet_hdr_len);
} else {
pkt = packet_new(s->sec_rs.buf,
s->sec_rs.packet_len,
s->sec_rs.vnet_hdr_len);
}
if (parse_packet_early(pkt)) {
packet_destroy(pkt, NULL);
pkt = NULL;
return -1;
}
fill_connection_key(pkt, &key);
conn = connection_get(s->connection_track_table,
&key,
&s->conn_list);
if (!conn->processing) {
g_queue_push_tail(&s->conn_list, conn);
conn->processing = true;
}
if (mode == PRIMARY_IN) {
ret = colo_insert_packet(&conn->primary_list, pkt, &conn->pack);
} else {
ret = colo_insert_packet(&conn->secondary_list, pkt, &conn->sack);
}
if (!ret) {
trace_colo_compare_drop_packet(colo_mode[mode],
"queue size too big, drop packet");
packet_destroy(pkt, NULL);
pkt = NULL;
}
*con = conn;
return 0;
}
static inline bool after(uint32_t seq1, uint32_t seq2)
{
return (int32_t)(seq1 - seq2) > 0;
}
static void colo_release_primary_pkt(CompareState *s, Packet *pkt)
{
int ret;
ret = compare_chr_send(s,
pkt->data,
pkt->size,
pkt->vnet_hdr_len,
false,
true);
if (ret < 0) {
error_report("colo send primary packet failed");
}
trace_colo_compare_main("packet same and release packet");
packet_destroy_partial(pkt, NULL);
}
/*
* The IP packets sent by primary and secondary
* will be compared in here
* TODO support ip fragment, Out-Of-Order
* return: 0 means packet same
* > 0 || < 0 means packet different
*/
static int colo_compare_packet_payload(Packet *ppkt,
Packet *spkt,
uint16_t poffset,
uint16_t soffset,
uint16_t len)
{
if (trace_event_get_state_backends(TRACE_COLO_COMPARE_MISCOMPARE)) {
char pri_ip_src[20], pri_ip_dst[20], sec_ip_src[20], sec_ip_dst[20];
strcpy(pri_ip_src, inet_ntoa(ppkt->ip->ip_src));
strcpy(pri_ip_dst, inet_ntoa(ppkt->ip->ip_dst));
strcpy(sec_ip_src, inet_ntoa(spkt->ip->ip_src));
strcpy(sec_ip_dst, inet_ntoa(spkt->ip->ip_dst));
trace_colo_compare_ip_info(ppkt->size, pri_ip_src,
pri_ip_dst, spkt->size,
sec_ip_src, sec_ip_dst);
}
return memcmp(ppkt->data + poffset, spkt->data + soffset, len);
}
/*
* return true means that the payload is consist and
* need to make the next comparison, false means do
* the checkpoint
*/
static bool colo_mark_tcp_pkt(Packet *ppkt, Packet *spkt,
int8_t *mark, uint32_t max_ack)
{
*mark = 0;
if (ppkt->tcp_seq == spkt->tcp_seq && ppkt->seq_end == spkt->seq_end) {
if (!colo_compare_packet_payload(ppkt, spkt,
ppkt->header_size, spkt->header_size,
ppkt->payload_size)) {
*mark = COLO_COMPARE_FREE_SECONDARY | COLO_COMPARE_FREE_PRIMARY;
return true;
}
}
/* one part of secondary packet payload still need to be compared */
if (!after(ppkt->seq_end, spkt->seq_end)) {
if (!colo_compare_packet_payload(ppkt, spkt,
ppkt->header_size + ppkt->offset,
spkt->header_size + spkt->offset,
ppkt->payload_size - ppkt->offset)) {
if (!after(ppkt->tcp_ack, max_ack)) {
*mark = COLO_COMPARE_FREE_PRIMARY;
spkt->offset += ppkt->payload_size - ppkt->offset;
return true;
} else {
/* secondary guest hasn't ack the data, don't send
* out this packet
*/
return false;
}
}
} else {
/* primary packet is longer than secondary packet, compare
* the same part and mark the primary packet offset
*/
if (!colo_compare_packet_payload(ppkt, spkt,
ppkt->header_size + ppkt->offset,
spkt->header_size + spkt->offset,
spkt->payload_size - spkt->offset)) {
*mark = COLO_COMPARE_FREE_SECONDARY;
ppkt->offset += spkt->payload_size - spkt->offset;
return true;
}
}
return false;
}
static void colo_compare_tcp(CompareState *s, Connection *conn)
{
Packet *ppkt = NULL, *spkt = NULL;
int8_t mark;
/*
* If ppkt and spkt have the same payload, but ppkt's ACK
* is greater than spkt's ACK, in this case we can not
* send the ppkt because it will cause the secondary guest
* to miss sending some data in the next. Therefore, we
* record the maximum ACK in the current queue at both
* primary side and secondary side. Only when the ack is
* less than the smaller of the two maximum ack, then we
* can ensure that the packet's payload is acknowledged by
* primary and secondary.
*/
uint32_t min_ack = conn->pack > conn->sack ? conn->sack : conn->pack;
pri:
if (g_queue_is_empty(&conn->primary_list)) {
return;
}
ppkt = g_queue_pop_head(&conn->primary_list);
sec:
if (g_queue_is_empty(&conn->secondary_list)) {
g_queue_push_head(&conn->primary_list, ppkt);
return;
}
spkt = g_queue_pop_head(&conn->secondary_list);
if (ppkt->tcp_seq == ppkt->seq_end) {
colo_release_primary_pkt(s, ppkt);
ppkt = NULL;
}
if (ppkt && conn->compare_seq && !after(ppkt->seq_end, conn->compare_seq)) {
trace_colo_compare_main("pri: this packet has compared");
colo_release_primary_pkt(s, ppkt);
ppkt = NULL;
}
if (spkt->tcp_seq == spkt->seq_end) {
packet_destroy(spkt, NULL);
if (!ppkt) {
goto pri;
} else {
goto sec;
}
} else {
if (conn->compare_seq && !after(spkt->seq_end, conn->compare_seq)) {
trace_colo_compare_main("sec: this packet has compared");
packet_destroy(spkt, NULL);
if (!ppkt) {
goto pri;
} else {
goto sec;
}
}
if (!ppkt) {
g_queue_push_head(&conn->secondary_list, spkt);
goto pri;
}
}
if (colo_mark_tcp_pkt(ppkt, spkt, &mark, min_ack)) {
trace_colo_compare_tcp_info("pri",
ppkt->tcp_seq, ppkt->tcp_ack,
ppkt->header_size, ppkt->payload_size,
ppkt->offset, ppkt->flags);
trace_colo_compare_tcp_info("sec",
spkt->tcp_seq, spkt->tcp_ack,
spkt->header_size, spkt->payload_size,
spkt->offset, spkt->flags);
if (mark == COLO_COMPARE_FREE_PRIMARY) {
conn->compare_seq = ppkt->seq_end;
colo_release_primary_pkt(s, ppkt);
g_queue_push_head(&conn->secondary_list, spkt);
goto pri;
}
if (mark == COLO_COMPARE_FREE_SECONDARY) {
conn->compare_seq = spkt->seq_end;
packet_destroy(spkt, NULL);
goto sec;
}
if (mark == (COLO_COMPARE_FREE_PRIMARY | COLO_COMPARE_FREE_SECONDARY)) {
conn->compare_seq = ppkt->seq_end;
colo_release_primary_pkt(s, ppkt);
packet_destroy(spkt, NULL);
goto pri;
}
} else {
g_queue_push_head(&conn->primary_list, ppkt);
g_queue_push_head(&conn->secondary_list, spkt);
if (trace_event_get_state_backends(TRACE_COLO_COMPARE_MISCOMPARE)) {
qemu_hexdump((char *)ppkt->data, stderr,
"colo-compare ppkt", ppkt->size);
qemu_hexdump((char *)spkt->data, stderr,
"colo-compare spkt", spkt->size);
}
colo_compare_inconsistency_notify(s);
}
}
/*
* Called from the compare thread on the primary
* for compare udp packet
*/
static int colo_packet_compare_udp(Packet *spkt, Packet *ppkt)
{
uint16_t network_header_length = ppkt->ip->ip_hl << 2;
uint16_t offset = network_header_length + ETH_HLEN + ppkt->vnet_hdr_len;
trace_colo_compare_main("compare udp");
/*
* Because of ppkt and spkt are both in the same connection,
* The ppkt's src ip, dst ip, src port, dst port, ip_proto all are
* same with spkt. In addition, IP header's Identification is a random
* field, we can handle it in IP fragmentation function later.
* COLO just concern the response net packet payload from primary guest
* and secondary guest are same or not, So we ignored all IP header include
* other field like TOS,TTL,IP Checksum. we only need to compare
* the ip payload here.
*/
if (ppkt->size != spkt->size) {
trace_colo_compare_main("UDP: payload size of packets are different");
return -1;
}
if (colo_compare_packet_payload(ppkt, spkt, offset, offset,
ppkt->size - offset)) {
trace_colo_compare_udp_miscompare("primary pkt size", ppkt->size);
trace_colo_compare_udp_miscompare("Secondary pkt size", spkt->size);
if (trace_event_get_state_backends(TRACE_COLO_COMPARE_MISCOMPARE)) {
qemu_hexdump((char *)ppkt->data, stderr, "colo-compare pri pkt",
ppkt->size);
qemu_hexdump((char *)spkt->data, stderr, "colo-compare sec pkt",
spkt->size);
}
return -1;
} else {
return 0;
}
}
/*
* Called from the compare thread on the primary
* for compare icmp packet
*/
static int colo_packet_compare_icmp(Packet *spkt, Packet *ppkt)
{
uint16_t network_header_length = ppkt->ip->ip_hl << 2;
uint16_t offset = network_header_length + ETH_HLEN + ppkt->vnet_hdr_len;
trace_colo_compare_main("compare icmp");
/*
* Because of ppkt and spkt are both in the same connection,
* The ppkt's src ip, dst ip, src port, dst port, ip_proto all are
* same with spkt. In addition, IP header's Identification is a random
* field, we can handle it in IP fragmentation function later.
* COLO just concern the response net packet payload from primary guest
* and secondary guest are same or not, So we ignored all IP header include
* other field like TOS,TTL,IP Checksum. we only need to compare
* the ip payload here.
*/
if (ppkt->size != spkt->size) {
trace_colo_compare_main("ICMP: payload size of packets are different");
return -1;
}
if (colo_compare_packet_payload(ppkt, spkt, offset, offset,
ppkt->size - offset)) {
trace_colo_compare_icmp_miscompare("primary pkt size",
ppkt->size);
trace_colo_compare_icmp_miscompare("Secondary pkt size",
spkt->size);
if (trace_event_get_state_backends(TRACE_COLO_COMPARE_MISCOMPARE)) {
qemu_hexdump((char *)ppkt->data, stderr, "colo-compare pri pkt",
ppkt->size);
qemu_hexdump((char *)spkt->data, stderr, "colo-compare sec pkt",
spkt->size);
}
return -1;
} else {
return 0;
}
}
/*
* Called from the compare thread on the primary
* for compare other packet
*/
static int colo_packet_compare_other(Packet *spkt, Packet *ppkt)
{
uint16_t offset = ppkt->vnet_hdr_len;
trace_colo_compare_main("compare other");
if (trace_event_get_state_backends(TRACE_COLO_COMPARE_MISCOMPARE)) {
char pri_ip_src[20], pri_ip_dst[20], sec_ip_src[20], sec_ip_dst[20];
strcpy(pri_ip_src, inet_ntoa(ppkt->ip->ip_src));
strcpy(pri_ip_dst, inet_ntoa(ppkt->ip->ip_dst));
strcpy(sec_ip_src, inet_ntoa(spkt->ip->ip_src));
strcpy(sec_ip_dst, inet_ntoa(spkt->ip->ip_dst));
trace_colo_compare_ip_info(ppkt->size, pri_ip_src,
pri_ip_dst, spkt->size,
sec_ip_src, sec_ip_dst);
}
if (ppkt->size != spkt->size) {
trace_colo_compare_main("Other: payload size of packets are different");
return -1;
}
return colo_compare_packet_payload(ppkt, spkt, offset, offset,
ppkt->size - offset);
}
static int colo_old_packet_check_one(Packet *pkt, int64_t *check_time)
{
int64_t now = qemu_clock_get_ms(QEMU_CLOCK_HOST);
if ((now - pkt->creation_ms) > (*check_time)) {
trace_colo_old_packet_check_found(pkt->creation_ms);
return 0;
} else {
return 1;
}
}
void colo_compare_register_notifier(Notifier *notify)
{
notifier_list_add(&colo_compare_notifiers, notify);
}
void colo_compare_unregister_notifier(Notifier *notify)
{
notifier_remove(notify);
}
static int colo_old_packet_check_one_conn(Connection *conn,
CompareState *s)
{
GList *result = NULL;
result = g_queue_find_custom(&conn->primary_list,
&s->compare_timeout,
(GCompareFunc)colo_old_packet_check_one);
if (result) {
/* Do checkpoint will flush old packet */
colo_compare_inconsistency_notify(s);
return 0;
}
return 1;
}
/*
* Look for old packets that the secondary hasn't matched,
* if we have some then we have to checkpoint to wake
* the secondary up.
*/
static void colo_old_packet_check(void *opaque)
{
CompareState *s = opaque;
/*
* If we find one old packet, stop finding job and notify
* COLO frame do checkpoint.
*/
g_queue_find_custom(&s->conn_list, s,
(GCompareFunc)colo_old_packet_check_one_conn);
}
static void colo_compare_packet(CompareState *s, Connection *conn,
int (*HandlePacket)(Packet *spkt,
Packet *ppkt))
{
Packet *pkt = NULL;
GList *result = NULL;
while (!g_queue_is_empty(&conn->primary_list) &&
!g_queue_is_empty(&conn->secondary_list)) {
pkt = g_queue_pop_head(&conn->primary_list);
result = g_queue_find_custom(&conn->secondary_list,
pkt, (GCompareFunc)HandlePacket);
if (result) {
colo_release_primary_pkt(s, pkt);
g_queue_remove(&conn->secondary_list, result->data);
} else {
/*
* If one packet arrive late, the secondary_list or
* primary_list will be empty, so we can't compare it
* until next comparison. If the packets in the list are
* timeout, it will trigger a checkpoint request.
*/
trace_colo_compare_main("packet different");
g_queue_push_head(&conn->primary_list, pkt);
colo_compare_inconsistency_notify(s);
break;
}
}
}
/*
* Called from the compare thread on the primary
* for compare packet with secondary list of the
* specified connection when a new packet was
* queued to it.
*/
static void colo_compare_connection(void *opaque, void *user_data)
{
CompareState *s = user_data;
Connection *conn = opaque;
switch (conn->ip_proto) {
case IPPROTO_TCP:
colo_compare_tcp(s, conn);
break;
case IPPROTO_UDP:
colo_compare_packet(s, conn, colo_packet_compare_udp);
break;
case IPPROTO_ICMP:
colo_compare_packet(s, conn, colo_packet_compare_icmp);
break;
default:
colo_compare_packet(s, conn, colo_packet_compare_other);
break;
}
}
static void coroutine_fn _compare_chr_send(void *opaque)
{
SendCo *sendco = opaque;
CompareState *s = sendco->s;
int ret = 0;
while (!g_queue_is_empty(&sendco->send_list)) {
SendEntry *entry = g_queue_pop_tail(&sendco->send_list);
uint32_t len = htonl(entry->size);
ret = qemu_chr_fe_write_all(sendco->chr, (uint8_t *)&len, sizeof(len));
if (ret != sizeof(len)) {
g_free(entry->buf);
g_slice_free(SendEntry, entry);
goto err;
}
if (!sendco->notify_remote_frame && s->vnet_hdr) {
/*
* We send vnet header len make other module(like filter-redirector)
* know how to parse net packet correctly.
*/
len = htonl(entry->vnet_hdr_len);
ret = qemu_chr_fe_write_all(sendco->chr,
(uint8_t *)&len,
sizeof(len));
if (ret != sizeof(len)) {
g_free(entry->buf);
g_slice_free(SendEntry, entry);
goto err;
}
}
ret = qemu_chr_fe_write_all(sendco->chr,
(uint8_t *)entry->buf,
entry->size);
if (ret != entry->size) {
g_free(entry->buf);
g_slice_free(SendEntry, entry);
goto err;
}
g_free(entry->buf);
g_slice_free(SendEntry, entry);
}
sendco->ret = 0;
goto out;
err:
while (!g_queue_is_empty(&sendco->send_list)) {
SendEntry *entry = g_queue_pop_tail(&sendco->send_list);
g_free(entry->buf);
g_slice_free(SendEntry, entry);
}
sendco->ret = ret < 0 ? ret : -EIO;
out:
sendco->co = NULL;
sendco->done = true;
aio_wait_kick();
}
static int compare_chr_send(CompareState *s,
uint8_t *buf,
uint32_t size,
uint32_t vnet_hdr_len,
bool notify_remote_frame,
bool zero_copy)
{
SendCo *sendco;
SendEntry *entry;
if (notify_remote_frame) {
sendco = &s->notify_sendco;
} else {
sendco = &s->out_sendco;
}
if (!size) {
return 0;
}
entry = g_slice_new(SendEntry);
entry->size = size;
entry->vnet_hdr_len = vnet_hdr_len;
if (zero_copy) {
entry->buf = buf;
} else {
entry->buf = g_malloc(size);
memcpy(entry->buf, buf, size);
}
g_queue_push_head(&sendco->send_list, entry);
if (sendco->done) {
sendco->co = qemu_coroutine_create(_compare_chr_send, sendco);
sendco->done = false;
qemu_coroutine_enter(sendco->co);
if (sendco->done) {
/* report early errors */
return sendco->ret;
}
}
/* assume success */
return 0;
}
static int compare_chr_can_read(void *opaque)
{
return COMPARE_READ_LEN_MAX;
}
/*
* Called from the main thread on the primary for packets
* arriving over the socket from the primary.
*/
static void compare_pri_chr_in(void *opaque, const uint8_t *buf, int size)
{
CompareState *s = COLO_COMPARE(opaque);
int ret;
ret = net_fill_rstate(&s->pri_rs, buf, size);
if (ret == -1) {
qemu_chr_fe_set_handlers(&s->chr_pri_in, NULL, NULL, NULL, NULL,
NULL, NULL, true);
error_report("colo-compare primary_in error");
}
}
/*
* Called from the main thread on the primary for packets
* arriving over the socket from the secondary.
*/
static void compare_sec_chr_in(void *opaque, const uint8_t *buf, int size)
{
CompareState *s = COLO_COMPARE(opaque);
int ret;
ret = net_fill_rstate(&s->sec_rs, buf, size);
if (ret == -1) {
qemu_chr_fe_set_handlers(&s->chr_sec_in, NULL, NULL, NULL, NULL,
NULL, NULL, true);
error_report("colo-compare secondary_in error");
}
}
static void compare_notify_chr(void *opaque, const uint8_t *buf, int size)
{
CompareState *s = COLO_COMPARE(opaque);
int ret;
ret = net_fill_rstate(&s->notify_rs, buf, size);
if (ret == -1) {
qemu_chr_fe_set_handlers(&s->chr_notify_dev, NULL, NULL, NULL, NULL,
NULL, NULL, true);
error_report("colo-compare notify_dev error");
}
}
/*
* Check old packet regularly so it can watch for any packets
* that the secondary hasn't produced equivalents of.
*/
static void check_old_packet_regular(void *opaque)
{
CompareState *s = opaque;
/* if have old packet we will notify checkpoint */
colo_old_packet_check(s);
timer_mod(s->packet_check_timer, qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) +
s->expired_scan_cycle);
}
/* Public API, Used for COLO frame to notify compare event */
void colo_notify_compares_event(void *opaque, int event, Error **errp)
{
CompareState *s;
qemu_mutex_lock(&colo_compare_mutex);
if (!colo_compare_active) {
qemu_mutex_unlock(&colo_compare_mutex);
return;
}
qemu_mutex_lock(&event_mtx);
QTAILQ_FOREACH(s, &net_compares, next) {
s->event = event;
qemu_bh_schedule(s->event_bh);
event_unhandled_count++;
}
/* Wait all compare threads to finish handling this event */
while (event_unhandled_count > 0) {
qemu_cond_wait(&event_complete_cond, &event_mtx);
}
qemu_mutex_unlock(&event_mtx);
qemu_mutex_unlock(&colo_compare_mutex);
}
static void colo_compare_timer_init(CompareState *s)
{
AioContext *ctx = iothread_get_aio_context(s->iothread);
s->packet_check_timer = aio_timer_new(ctx, QEMU_CLOCK_VIRTUAL,
SCALE_MS, check_old_packet_regular,
s);
timer_mod(s->packet_check_timer, qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) +
s->expired_scan_cycle);
}
static void colo_compare_timer_del(CompareState *s)
{
if (s->packet_check_timer) {
timer_del(s->packet_check_timer);
timer_free(s->packet_check_timer);
s->packet_check_timer = NULL;
}
}
static void colo_flush_packets(void *opaque, void *user_data);
static void colo_compare_handle_event(void *opaque)
{
CompareState *s = opaque;
switch (s->event) {
case COLO_EVENT_CHECKPOINT:
g_queue_foreach(&s->conn_list, colo_flush_packets, s);
break;
case COLO_EVENT_FAILOVER:
break;
default:
break;
}
qemu_mutex_lock(&event_mtx);
assert(event_unhandled_count > 0);
event_unhandled_count--;
qemu_cond_broadcast(&event_complete_cond);
qemu_mutex_unlock(&event_mtx);
}
static void colo_compare_iothread(CompareState *s)
{
AioContext *ctx = iothread_get_aio_context(s->iothread);
object_ref(OBJECT(s->iothread));
s->worker_context = iothread_get_g_main_context(s->iothread);
qemu_chr_fe_set_handlers(&s->chr_pri_in, compare_chr_can_read,
compare_pri_chr_in, NULL, NULL,
s, s->worker_context, true);
qemu_chr_fe_set_handlers(&s->chr_sec_in, compare_chr_can_read,
compare_sec_chr_in, NULL, NULL,
s, s->worker_context, true);
if (s->notify_dev) {
qemu_chr_fe_set_handlers(&s->chr_notify_dev, compare_chr_can_read,
compare_notify_chr, NULL, NULL,
s, s->worker_context, true);
}
colo_compare_timer_init(s);
s->event_bh = aio_bh_new(ctx, colo_compare_handle_event, s);
}
static char *compare_get_pri_indev(Object *obj, Error **errp)
{
CompareState *s = COLO_COMPARE(obj);
return g_strdup(s->pri_indev);
}
static void compare_set_pri_indev(Object *obj, const char *value, Error **errp)
{
CompareState *s = COLO_COMPARE(obj);
g_free(s->pri_indev);
s->pri_indev = g_strdup(value);
}
static char *compare_get_sec_indev(Object *obj, Error **errp)
{
CompareState *s = COLO_COMPARE(obj);
return g_strdup(s->sec_indev);
}
static void compare_set_sec_indev(Object *obj, const char *value, Error **errp)
{
CompareState *s = COLO_COMPARE(obj);
g_free(s->sec_indev);
s->sec_indev = g_strdup(value);
}
static char *compare_get_outdev(Object *obj, Error **errp)
{
CompareState *s = COLO_COMPARE(obj);
return g_strdup(s->outdev);
}
static void compare_set_outdev(Object *obj, const char *value, Error **errp)
{
CompareState *s = COLO_COMPARE(obj);
g_free(s->outdev);
s->outdev = g_strdup(value);
}
static bool compare_get_vnet_hdr(Object *obj, Error **errp)
{
CompareState *s = COLO_COMPARE(obj);
return s->vnet_hdr;
}
static void compare_set_vnet_hdr(Object *obj,
bool value,
Error **errp)
{
CompareState *s = COLO_COMPARE(obj);
s->vnet_hdr = value;
}
static char *compare_get_notify_dev(Object *obj, Error **errp)
{
CompareState *s = COLO_COMPARE(obj);
return g_strdup(s->notify_dev);
}
static void compare_set_notify_dev(Object *obj, const char *value, Error **errp)
{
CompareState *s = COLO_COMPARE(obj);
g_free(s->notify_dev);
s->notify_dev = g_strdup(value);
}
static void compare_get_timeout(Object *obj, Visitor *v,
const char *name, void *opaque,
Error **errp)
{
CompareState *s = COLO_COMPARE(obj);
uint32_t value = s->compare_timeout;
visit_type_uint32(v, name, &value, errp);
}
static void compare_set_timeout(Object *obj, Visitor *v,
const char *name, void *opaque,
Error **errp)
{
CompareState *s = COLO_COMPARE(obj);
uint32_t value;
if (!visit_type_uint32(v, name, &value, errp)) {
return;
}
if (!value) {
error_setg(errp, "Property '%s.%s' requires a positive value",
object_get_typename(obj), name);
return;
}
s->compare_timeout = value;
}
static void compare_get_expired_scan_cycle(Object *obj, Visitor *v,
const char *name, void *opaque,
Error **errp)
{
CompareState *s = COLO_COMPARE(obj);
uint32_t value = s->expired_scan_cycle;
visit_type_uint32(v, name, &value, errp);
}
static void compare_set_expired_scan_cycle(Object *obj, Visitor *v,
const char *name, void *opaque,
Error **errp)
{
CompareState *s = COLO_COMPARE(obj);
uint32_t value;
if (!visit_type_uint32(v, name, &value, errp)) {
return;
}
if (!value) {
error_setg(errp, "Property '%s.%s' requires a positive value",
object_get_typename(obj), name);
return;
}
s->expired_scan_cycle = value;
}
static void compare_pri_rs_finalize(SocketReadState *pri_rs)
{
CompareState *s = container_of(pri_rs, CompareState, pri_rs);
Connection *conn = NULL;
if (packet_enqueue(s, PRIMARY_IN, &conn)) {
trace_colo_compare_main("primary: unsupported packet in");
compare_chr_send(s,
pri_rs->buf,
pri_rs->packet_len,
pri_rs->vnet_hdr_len,
false,
false);
} else {
/* compare packet in the specified connection */
colo_compare_connection(conn, s);
}
}
static void compare_sec_rs_finalize(SocketReadState *sec_rs)
{
CompareState *s = container_of(sec_rs, CompareState, sec_rs);
Connection *conn = NULL;
if (packet_enqueue(s, SECONDARY_IN, &conn)) {
trace_colo_compare_main("secondary: unsupported packet in");
} else {
/* compare packet in the specified connection */
colo_compare_connection(conn, s);
}
}
static void compare_notify_rs_finalize(SocketReadState *notify_rs)
{
CompareState *s = container_of(notify_rs, CompareState, notify_rs);
const char msg[] = "COLO_COMPARE_GET_XEN_INIT";
int ret;
if (packet_matches_str("COLO_USERSPACE_PROXY_INIT",
notify_rs->buf,
notify_rs->packet_len)) {
ret = compare_chr_send(s, (uint8_t *)msg, strlen(msg), 0, true, false);
if (ret < 0) {
error_report("Notify Xen COLO-frame INIT failed");
}
} else if (packet_matches_str("COLO_CHECKPOINT",
notify_rs->buf,
notify_rs->packet_len)) {
/* colo-compare do checkpoint, flush pri packet and remove sec packet */
g_queue_foreach(&s->conn_list, colo_flush_packets, s);
} else {
error_report("COLO compare got unsupported instruction");
}
}
/*
* Return 0 is success.
* Return 1 is failed.
*/
static int find_and_check_chardev(Chardev **chr,
char *chr_name,
Error **errp)
{
*chr = qemu_chr_find(chr_name);
if (*chr == NULL) {
error_setg(errp, "Device '%s' not found",
chr_name);
return 1;
}
if (!qemu_chr_has_feature(*chr, QEMU_CHAR_FEATURE_RECONNECTABLE)) {
error_setg(errp, "chardev \"%s\" is not reconnectable",
chr_name);
return 1;
}
if (!qemu_chr_has_feature(*chr, QEMU_CHAR_FEATURE_GCONTEXT)) {
error_setg(errp, "chardev \"%s\" cannot switch context",
chr_name);
return 1;
}
return 0;
}
/*
* Called from the main thread on the primary
* to setup colo-compare.
*/
static void colo_compare_complete(UserCreatable *uc, Error **errp)
{
CompareState *s = COLO_COMPARE(uc);
Chardev *chr;
if (!s->pri_indev || !s->sec_indev || !s->outdev || !s->iothread) {
error_setg(errp, "colo compare needs 'primary_in' ,"
"'secondary_in','outdev','iothread' property set");
return;
} else if (!strcmp(s->pri_indev, s->outdev) ||
!strcmp(s->sec_indev, s->outdev) ||
!strcmp(s->pri_indev, s->sec_indev)) {
error_setg(errp, "'indev' and 'outdev' could not be same "
"for compare module");
return;
}
if (!s->compare_timeout) {
/* Set default value to 3000 MS */
s->compare_timeout = DEFAULT_TIME_OUT_MS;
}
if (!s->expired_scan_cycle) {
/* Set default value to 3000 MS */
s->expired_scan_cycle = REGULAR_PACKET_CHECK_MS;
}
if (find_and_check_chardev(&chr, s->pri_indev, errp) ||
!qemu_chr_fe_init(&s->chr_pri_in, chr, errp)) {
return;
}
if (find_and_check_chardev(&chr, s->sec_indev, errp) ||
!qemu_chr_fe_init(&s->chr_sec_in, chr, errp)) {
return;
}
if (find_and_check_chardev(&chr, s->outdev, errp) ||
!qemu_chr_fe_init(&s->chr_out, chr, errp)) {
return;
}
net_socket_rs_init(&s->pri_rs, compare_pri_rs_finalize, s->vnet_hdr);
net_socket_rs_init(&s->sec_rs, compare_sec_rs_finalize, s->vnet_hdr);
/* Try to enable remote notify chardev, currently just for Xen COLO */
if (s->notify_dev) {
if (find_and_check_chardev(&chr, s->notify_dev, errp) ||
!qemu_chr_fe_init(&s->chr_notify_dev, chr, errp)) {
return;
}
net_socket_rs_init(&s->notify_rs, compare_notify_rs_finalize,
s->vnet_hdr);
}
s->out_sendco.s = s;
s->out_sendco.chr = &s->chr_out;
s->out_sendco.notify_remote_frame = false;
s->out_sendco.done = true;
g_queue_init(&s->out_sendco.send_list);
if (s->notify_dev) {
s->notify_sendco.s = s;
s->notify_sendco.chr = &s->chr_notify_dev;
s->notify_sendco.notify_remote_frame = true;
s->notify_sendco.done = true;
g_queue_init(&s->notify_sendco.send_list);
}
g_queue_init(&s->conn_list);
s->connection_track_table = g_hash_table_new_full(connection_key_hash,
connection_key_equal,
g_free,
connection_destroy);
colo_compare_iothread(s);
qemu_mutex_lock(&colo_compare_mutex);
if (!colo_compare_active) {
qemu_mutex_init(&event_mtx);
qemu_cond_init(&event_complete_cond);
colo_compare_active = true;
}
QTAILQ_INSERT_TAIL(&net_compares, s, next);
qemu_mutex_unlock(&colo_compare_mutex);
return;
}
static void colo_flush_packets(void *opaque, void *user_data)
{
CompareState *s = user_data;
Connection *conn = opaque;
Packet *pkt = NULL;
while (!g_queue_is_empty(&conn->primary_list)) {
pkt = g_queue_pop_head(&conn->primary_list);
compare_chr_send(s,
pkt->data,
pkt->size,
pkt->vnet_hdr_len,
false,
true);
packet_destroy_partial(pkt, NULL);
}
while (!g_queue_is_empty(&conn->secondary_list)) {
pkt = g_queue_pop_head(&conn->secondary_list);
packet_destroy(pkt, NULL);
}
}
static void colo_compare_class_init(ObjectClass *oc, void *data)
{
UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
ucc->complete = colo_compare_complete;
}
static void colo_compare_init(Object *obj)
{
CompareState *s = COLO_COMPARE(obj);
object_property_add_str(obj, "primary_in",
compare_get_pri_indev, compare_set_pri_indev);
object_property_add_str(obj, "secondary_in",
compare_get_sec_indev, compare_set_sec_indev);
object_property_add_str(obj, "outdev",
compare_get_outdev, compare_set_outdev);
object_property_add_link(obj, "iothread", TYPE_IOTHREAD,
(Object **)&s->iothread,
object_property_allow_set_link,
OBJ_PROP_LINK_STRONG);
/* This parameter just for Xen COLO */
object_property_add_str(obj, "notify_dev",
compare_get_notify_dev, compare_set_notify_dev);
object_property_add(obj, "compare_timeout", "uint32",
compare_get_timeout,
compare_set_timeout, NULL, NULL);
object_property_add(obj, "expired_scan_cycle", "uint32",
compare_get_expired_scan_cycle,
compare_set_expired_scan_cycle, NULL, NULL);
s->vnet_hdr = false;
object_property_add_bool(obj, "vnet_hdr_support", compare_get_vnet_hdr,
compare_set_vnet_hdr);
}
static void colo_compare_finalize(Object *obj)
{
CompareState *s = COLO_COMPARE(obj);
CompareState *tmp = NULL;
qemu_mutex_lock(&colo_compare_mutex);
QTAILQ_FOREACH(tmp, &net_compares, next) {
if (tmp == s) {
QTAILQ_REMOVE(&net_compares, s, next);
break;
}
}
if (QTAILQ_EMPTY(&net_compares)) {
colo_compare_active = false;
qemu_mutex_destroy(&event_mtx);
qemu_cond_destroy(&event_complete_cond);
}
qemu_mutex_unlock(&colo_compare_mutex);
qemu_chr_fe_deinit(&s->chr_pri_in, false);
qemu_chr_fe_deinit(&s->chr_sec_in, false);
qemu_chr_fe_deinit(&s->chr_out, false);
if (s->notify_dev) {
qemu_chr_fe_deinit(&s->chr_notify_dev, false);
}
if (s->iothread) {
colo_compare_timer_del(s);
}
qemu_bh_delete(s->event_bh);
AioContext *ctx = iothread_get_aio_context(s->iothread);
aio_context_acquire(ctx);
AIO_WAIT_WHILE(ctx, !s->out_sendco.done);
if (s->notify_dev) {
AIO_WAIT_WHILE(ctx, !s->notify_sendco.done);
}
aio_context_release(ctx);
/* Release all unhandled packets after compare thead exited */
g_queue_foreach(&s->conn_list, colo_flush_packets, s);
AIO_WAIT_WHILE(NULL, !s->out_sendco.done);
g_queue_clear(&s->conn_list);
g_queue_clear(&s->out_sendco.send_list);
if (s->notify_dev) {
g_queue_clear(&s->notify_sendco.send_list);
}
if (s->connection_track_table) {
g_hash_table_destroy(s->connection_track_table);
}
if (s->iothread) {
object_unref(OBJECT(s->iothread));
}
g_free(s->pri_indev);
g_free(s->sec_indev);
g_free(s->outdev);
g_free(s->notify_dev);
}
static void __attribute__((__constructor__)) colo_compare_init_globals(void)
{
colo_compare_active = false;
qemu_mutex_init(&colo_compare_mutex);
}
static const TypeInfo colo_compare_info = {
.name = TYPE_COLO_COMPARE,
.parent = TYPE_OBJECT,
.instance_size = sizeof(CompareState),
.instance_init = colo_compare_init,
.instance_finalize = colo_compare_finalize,
.class_size = sizeof(CompareClass),
.class_init = colo_compare_class_init,
.interfaces = (InterfaceInfo[]) {
{ TYPE_USER_CREATABLE },
{ }
}
};
static void register_types(void)
{
type_register_static(&colo_compare_info);
}
type_init(register_types);