[Qemu-devel] [PATCH V9 00/20] COLO: integrate colo frame with block replication and COLO proxy

[Qemu-devel] [PATCH V9 00/20] COLO: integrate colo frame with block replication and COLO proxy

[Zhang Chen]

Hi~ All~

COLO Frame, block replication and COLO proxy(colo-compare,filter-mirror,
filter-redirector,filter-rewriter) have been exist in qemu
for long time, it's time to integrate these three parts to make COLO really works.

In this series, we have some optimizations for COLO frame, including separating the
process of saving ram and device state, using an COLO_EXIT event to notify users that
VM exits COLO, for these parts, most of them have been reviewed long time ago in old version,
but since this series have just rebased on upstream which had merged a new series of migration,
parts of pathes in this series deserve review again.

We use notifier/callback method for COLO compare to notify COLO frame about
net packets inconsistent event, and add a handle_event method for NetFilterClass to
help COLO frame to notify filters and colo-compare about checkpoint/failover event,
it is flexible.

For the neweset version, please refer to:
https://github.com/zhangckid/qemu/tree/qemu-colo-18jun25

Please review, thanks.

V9:
 - Rebased on upstream codes.
 - Addressed Jason's comments add TCP state machine track in
   filter-rewriter.
 - Fix some bug in colo-compare.
 - Fix typo.
 - Add filter-rewriter failover handle.
 - Add net client type check in colo-compare.
 - Add COLO state diagram.
 - Addressed Markus and Daive's comments.


V8:
 - Rebased on upstream codes.
 - Addressed Markus's comments in patch 10/17.
 - Addressed Markus's comments in patch 11/17.
 - Removed some comments in patch 4/17.
 - Moved the "migration_bitmap_clear_dirty()" to suitable position in
   patch 9/17.
 - Rewrote the patch 07/17 to address Davie's comments.
 - Moved the "qemu_savevm_live_state" out of the
   qemu_mutex_lock_iothread.
 - Fixed the bug that in some status COLO vm crash with segmentation fault.

V7:
 - Addressed Markus's comments in 11/17.
 - Rebased on upstream.

V6:
 - Addressed Eric Blake's comments, use the enum to feedback in patch 11/17.
 - Fixed QAPI command separator problem in patch 11/17.



Zhang Chen (16):
  filter-rewriter: Add TCP state machine and fix memory leak in
    connection_track_table
  colo-compare: implement the process of checkpoint
  colo-compare: use notifier to notify packets comparing result
  COLO: integrate colo compare with colo frame
  COLO: Add block replication into colo process
  COLO: Remove colo_state migration struct
  COLO: Load dirty pages into SVM's RAM cache firstly
  ram/COLO: Record the dirty pages that SVM received
  COLO: Flush memory data from ram cache
  qapi/migration.json: Rename COLO unknown mode to none mode.
  qapi: Add new command to query colo status
  savevm: split the process of different stages for loadvm/savevm
  net/net.c: Add net client type check function for COLO
  filter: Add handle_event method for NetFilterClass
  filter-rewriter: handle checkpoint and failover event
  docs: Add COLO status diagram to COLO-FT.txt

zhanghailiang (4):
  qmp event: Add COLO_EXIT event to notify users while exited COLO
  COLO: flush host dirty ram from cache
  COLO: notify net filters about checkpoint/failover event
  COLO: quick failover process by kick COLO thread

 docs/COLO-FT.txt          |  34 ++++++
 include/exec/ram_addr.h   |   1 +
 include/migration/colo.h  |  11 +-
 include/net/filter.h      |   5 +
 include/net/net.h         |   1 +
 migration/Makefile.objs   |   2 +-
 migration/colo-comm.c     |  76 -------------
 migration/colo-failover.c |   2 +-
 migration/colo.c          | 230 ++++++++++++++++++++++++++++++++++++--
 migration/migration.c     |  44 +++++++-
 migration/ram.c           | 163 ++++++++++++++++++++++++++-
 migration/ram.h           |   4 +
 migration/savevm.c        |  53 +++++++--
 migration/savevm.h        |   5 +
 migration/trace-events    |   3 +
 net/colo-compare.c        | 120 ++++++++++++++++++--
 net/colo-compare.h        |  24 ++++
 net/colo.c                |  10 +-
 net/colo.h                |  11 +-
 net/filter-rewriter.c     | 162 +++++++++++++++++++++++++--
 net/filter.c              |  17 +++
 net/net.c                 |  42 +++++++
 qapi/migration.json       |  82 +++++++++++++-
 vl.c                      |   2 -
 24 files changed, 965 insertions(+), 139 deletions(-)
 delete mode 100644 migration/colo-comm.c
 create mode 100644 net/colo-compare.h

-- 
2.17.GIT

[Qemu-devel] [PATCH V9 01/20] filter-rewriter: Add TCP state machine and fix memory leak in connection_track_table

[Zhang Chen]

We add almost full TCP state machine in filter-rewriter, except
TCPS_LISTEN and some simplify in VM active close FIN states.

After a net connection is closed, we didn't clear its releated resources
in connection_track_table, which will lead to memory leak.

Let't track the state of net connection, if it is closed, its related
resources will be cleared up.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Zhang Chen <zhangckid@gmail.com>
---
 net/colo.c            |   2 +-
 net/colo.h            |   9 ++--
 net/filter-rewriter.c | 105 ++++++++++++++++++++++++++++++++++++++----
 3 files changed, 100 insertions(+), 16 deletions(-)

diff --git a/net/colo.c b/net/colo.c
index 6dda4ed66e..97c8fc928f 100644
--- a/net/colo.c
+++ b/net/colo.c
@@ -137,7 +137,7 @@ Connection *connection_new(ConnectionKey *key)
     conn->ip_proto = key->ip_proto;
     conn->processing = false;
     conn->offset = 0;
-    conn->syn_flag = 0;
+    conn->tcp_state = TCPS_CLOSED;
     conn->pack = 0;
     conn->sack = 0;
     g_queue_init(&conn->primary_list);
diff --git a/net/colo.h b/net/colo.h
index da6c36dcf7..0277e0e9ba 100644
--- a/net/colo.h
+++ b/net/colo.h
@@ -18,6 +18,7 @@
 #include "slirp/slirp.h"
 #include "qemu/jhash.h"
 #include "qemu/timer.h"
+#include "slirp/tcp.h"
 
 #define HASHTABLE_MAX_SIZE 16384
 
@@ -81,11 +82,9 @@ typedef struct Connection {
     uint32_t sack;
     /* offset = secondary_seq - primary_seq */
     tcp_seq  offset;
-    /*
-     * we use this flag update offset func
-     * run once in independent tcp connection
-     */
-    int syn_flag;
+
+    int tcp_state; /* TCP FSM state */
+    tcp_seq fin_ack_seq; /* the seq of 'fin=1,ack=1' */
 } Connection;
 
 uint32_t connection_key_hash(const void *opaque);
diff --git a/net/filter-rewriter.c b/net/filter-rewriter.c
index f584e4eba4..f18a71bf2e 100644
--- a/net/filter-rewriter.c
+++ b/net/filter-rewriter.c
@@ -59,9 +59,9 @@ static int is_tcp_packet(Packet *pkt)
 }
 
 /* handle tcp packet from primary guest */
-static int handle_primary_tcp_pkt(NetFilterState *nf,
+static int handle_primary_tcp_pkt(RewriterState *rf,
                                   Connection *conn,
-                                  Packet *pkt)
+                                  Packet *pkt, ConnectionKey *key)
 {
     struct tcphdr *tcp_pkt;
 
@@ -74,23 +74,28 @@ static int handle_primary_tcp_pkt(NetFilterState *nf,
         trace_colo_filter_rewriter_conn_offset(conn->offset);
     }
 
+    if (((tcp_pkt->th_flags & (TH_ACK | TH_SYN)) == (TH_ACK | TH_SYN)) &&
+        conn->tcp_state == TCPS_SYN_SENT) {
+        conn->tcp_state = TCPS_ESTABLISHED;
+    }
+
     if (((tcp_pkt->th_flags & (TH_ACK | TH_SYN)) == TH_SYN)) {
         /*
          * we use this flag update offset func
          * run once in independent tcp connection
          */
-        conn->syn_flag = 1;
+        conn->tcp_state = TCPS_SYN_RECEIVED;
     }
 
     if (((tcp_pkt->th_flags & (TH_ACK | TH_SYN)) == TH_ACK)) {
-        if (conn->syn_flag) {
+        if (conn->tcp_state == TCPS_SYN_RECEIVED) {
             /*
              * offset = secondary_seq - primary seq
              * ack packet sent by guest from primary node,
              * so we use th_ack - 1 get primary_seq
              */
             conn->offset -= (ntohl(tcp_pkt->th_ack) - 1);
-            conn->syn_flag = 0;
+            conn->tcp_state = TCPS_ESTABLISHED;
         }
         if (conn->offset) {
             /* handle packets to the secondary from the primary */
@@ -99,15 +104,63 @@ static int handle_primary_tcp_pkt(NetFilterState *nf,
             net_checksum_calculate((uint8_t *)pkt->data + pkt->vnet_hdr_len,
                                    pkt->size - pkt->vnet_hdr_len);
         }
+        /*
+         * Case 1:
+         * Step 3:
+         * The *server* side of this connect is VM, *client* tries to close
+         * the connection.
+         *
+         * We got 'ack=1' packets from client side, it acks 'fin=1, ack=1'
+         * packet from server side. From this point, we can ensure that there
+         * will be no packets in the connection, except that, some errors
+         * happen between the path of 'filter object' and vNIC, if this rare
+         * case really happen, we can still create a new connection,
+         * So it is safe to remove the connection from connection_track_table.
+         *
+         */
+        if ((conn->tcp_state == TCPS_LAST_ACK) &&
+            (ntohl(tcp_pkt->th_ack) == (conn->fin_ack_seq + 1))) {
+            conn->tcp_state = TCPS_CLOSED;
+            g_hash_table_remove(rf->connection_track_table, key);
+        }
+    }
+
+    if ((tcp_pkt->th_flags & TH_FIN) == TH_FIN) {
+        /*
+         * Case 1:
+         * Step 1:
+         * The *server* side of this connect is VM, *client* tries to close
+         * the connection. We will into CLOSE_WAIT status.
+         */
+        if (conn->tcp_state == TCPS_ESTABLISHED) {
+            conn->tcp_state = TCPS_CLOSE_WAIT;
+        }
+
+        /*
+         * Case 2:
+         * Step 2:
+         * The *server* side of this connect is VM, *server* tries to close
+         * the connection. We will into CLOSE_WAIT status.
+         * We simplify the TCPS_FIN_WAIT_2, TCPS_TIME_WAIT and CLOSING status.
+         */
+        if (conn->tcp_state == TCPS_FIN_WAIT_1) {
+            conn->tcp_state = TCPS_TIME_WAIT;
+            /*
+             * For simplify implementation, we needn't wait 2MSL time
+             * in filter rewriter.
+             */
+            conn->tcp_state = TCPS_CLOSED;
+            g_hash_table_remove(rf->connection_track_table, key);
+        }
     }
 
     return 0;
 }
 
 /* handle tcp packet from secondary guest */
-static int handle_secondary_tcp_pkt(NetFilterState *nf,
+static int handle_secondary_tcp_pkt(RewriterState *rf,
                                     Connection *conn,
-                                    Packet *pkt)
+                                    Packet *pkt, ConnectionKey *key)
 {
     struct tcphdr *tcp_pkt;
 
@@ -121,7 +174,8 @@ static int handle_secondary_tcp_pkt(NetFilterState *nf,
         trace_colo_filter_rewriter_conn_offset(conn->offset);
     }
 
-    if (((tcp_pkt->th_flags & (TH_ACK | TH_SYN)) == (TH_ACK | TH_SYN))) {
+    if (conn->tcp_state == TCPS_SYN_RECEIVED &&
+        ((tcp_pkt->th_flags & (TH_ACK | TH_SYN)) == (TH_ACK | TH_SYN))) {
         /*
          * save offset = secondary_seq and then
          * in handle_primary_tcp_pkt make offset
@@ -130,6 +184,12 @@ static int handle_secondary_tcp_pkt(NetFilterState *nf,
         conn->offset = ntohl(tcp_pkt->th_seq);
     }
 
+    /* VM active connect */
+    if (conn->tcp_state == TCPS_CLOSED &&
+        ((tcp_pkt->th_flags & (TH_ACK | TH_SYN)) == TH_SYN)) {
+        conn->tcp_state = TCPS_SYN_SENT;
+    }
+
     if ((tcp_pkt->th_flags & (TH_ACK | TH_SYN)) == TH_ACK) {
         /* Only need to adjust seq while offset is Non-zero */
         if (conn->offset) {
@@ -140,6 +200,31 @@ static int handle_secondary_tcp_pkt(NetFilterState *nf,
                                    pkt->size - pkt->vnet_hdr_len);
         }
     }
+    /*
+     * Case 1:
+     * Step 2:
+     * The *server* side of this connect is VM, *client* tries to close
+     * the connection. In this step we will into LAST_ACK status.
+     *
+     * We got 'fin=1, ack=1' packet from server side, we need to
+     * record the seq of 'fin=1, ack=1' packet.
+     */
+    if (conn->tcp_state == TCPS_CLOSE_WAIT &&
+        (tcp_pkt->th_flags & (TH_ACK | TH_FIN)) == (TH_ACK | TH_FIN)) {
+        conn->fin_ack_seq = ntohl(tcp_pkt->th_seq);
+        conn->tcp_state = TCPS_LAST_ACK;
+    }
+
+    /*
+     * Case 2:
+     * Step 1:
+     * The *server* side of this connect is VM, *server* tries to close
+     * the connection.
+     */
+    if (conn->tcp_state == TCPS_ESTABLISHED &&
+        (tcp_pkt->th_flags & (TH_ACK | TH_FIN)) == TH_FIN) {
+        conn->tcp_state = TCPS_FIN_WAIT_1;
+    }
 
     return 0;
 }
@@ -190,7 +275,7 @@ static ssize_t colo_rewriter_receive_iov(NetFilterState *nf,
 
         if (sender == nf->netdev) {
             /* NET_FILTER_DIRECTION_TX */
-            if (!handle_primary_tcp_pkt(nf, conn, pkt)) {
+            if (!handle_primary_tcp_pkt(s, conn, pkt, &key)) {
                 qemu_net_queue_send(s->incoming_queue, sender, 0,
                 (const uint8_t *)pkt->data, pkt->size, NULL);
                 packet_destroy(pkt, NULL);
@@ -203,7 +288,7 @@ static ssize_t colo_rewriter_receive_iov(NetFilterState *nf,
             }
         } else {
             /* NET_FILTER_DIRECTION_RX */
-            if (!handle_secondary_tcp_pkt(nf, conn, pkt)) {
+            if (!handle_secondary_tcp_pkt(s, conn, pkt, &key)) {
                 qemu_net_queue_send(s->incoming_queue, sender, 0,
                 (const uint8_t *)pkt->data, pkt->size, NULL);
                 packet_destroy(pkt, NULL);
-- 
2.17.GIT

[Qemu-devel] [PATCH V9 02/20] colo-compare: implement the process of checkpoint

[Zhang Chen]

While do checkpoint, we need to flush all the unhandled packets,
By using the filter notifier mechanism, we can easily to notify
every compare object to do this process, which runs inside
of compare threads as a coroutine.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Zhang Chen <zhangckid@gmail.com>
---
 include/migration/colo.h |  6 ++++
 net/colo-compare.c       | 78 ++++++++++++++++++++++++++++++++++++++++
 net/colo-compare.h       | 22 ++++++++++++
 3 files changed, 106 insertions(+)
 create mode 100644 net/colo-compare.h

diff --git a/include/migration/colo.h b/include/migration/colo.h
index 2fe48ad353..fefb2fcf4c 100644
--- a/include/migration/colo.h
+++ b/include/migration/colo.h
@@ -16,6 +16,12 @@
 #include "qemu-common.h"
 #include "qapi/qapi-types-migration.h"
 
+enum colo_event {
+    COLO_EVENT_NONE,
+    COLO_EVENT_CHECKPOINT,
+    COLO_EVENT_FAILOVER,
+};
+
 void colo_info_init(void);
 
 void migrate_start_colo_process(MigrationState *s);
diff --git a/net/colo-compare.c b/net/colo-compare.c
index dd745a491b..80e6532e8b 100644
--- a/net/colo-compare.c
+++ b/net/colo-compare.c
@@ -27,11 +27,16 @@
 #include "qemu/sockets.h"
 #include "colo.h"
 #include "sysemu/iothread.h"
+#include "net/colo-compare.h"
+#include "migration/colo.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);
+
 #define COMPARE_READ_LEN_MAX NET_BUFSIZE
 #define MAX_QUEUE_SIZE 1024
 
@@ -41,6 +46,10 @@
 /* TODO: Should be configurable */
 #define REGULAR_PACKET_CHECK_MS 3000
 
+static QemuMutex event_mtx;
+static QemuCond event_complete_cond;
+static int event_unhandled_count;
+
 /*
  *  + CompareState ++
  *  |               |
@@ -87,6 +96,11 @@ typedef struct CompareState {
     IOThread *iothread;
     GMainContext *worker_context;
     QEMUTimer *packet_check_timer;
+
+    QEMUBH *event_bh;
+    enum colo_event event;
+
+    QTAILQ_ENTRY(CompareState) next;
 } CompareState;
 
 typedef struct CompareClass {
@@ -736,6 +750,25 @@ static void check_old_packet_regular(void *opaque)
                 REGULAR_PACKET_CHECK_MS);
 }
 
+/* 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(&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);
+}
+
 static void colo_compare_timer_init(CompareState *s)
 {
     AioContext *ctx = iothread_get_aio_context(s->iothread);
@@ -756,6 +789,30 @@ static void colo_compare_timer_del(CompareState *s)
     }
  }
 
+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;
+    }
+
+    assert(event_unhandled_count > 0);
+
+    qemu_mutex_lock(&event_mtx);
+    event_unhandled_count--;
+    qemu_cond_broadcast(&event_complete_cond);
+    qemu_mutex_unlock(&event_mtx);
+}
+
 static void colo_compare_iothread(CompareState *s)
 {
     object_ref(OBJECT(s->iothread));
@@ -769,6 +826,7 @@ static void colo_compare_iothread(CompareState *s)
                              s, s->worker_context, true);
 
     colo_compare_timer_init(s);
+    s->event_bh = qemu_bh_new(colo_compare_handle_event, s);
 }
 
 static char *compare_get_pri_indev(Object *obj, Error **errp)
@@ -926,8 +984,13 @@ static void colo_compare_complete(UserCreatable *uc, Error **errp)
     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);
 
+    QTAILQ_INSERT_TAIL(&net_compares, s, next);
+
     g_queue_init(&s->conn_list);
 
+    qemu_mutex_init(&event_mtx);
+    qemu_cond_init(&event_complete_cond);
+
     s->connection_track_table = g_hash_table_new_full(connection_key_hash,
                                                       connection_key_equal,
                                                       g_free,
@@ -990,6 +1053,7 @@ static void colo_compare_init(Object *obj)
 static void colo_compare_finalize(Object *obj)
 {
     CompareState *s = COLO_COMPARE(obj);
+    CompareState *tmp = NULL;
 
     qemu_chr_fe_deinit(&s->chr_pri_in, false);
     qemu_chr_fe_deinit(&s->chr_sec_in, false);
@@ -997,6 +1061,16 @@ static void colo_compare_finalize(Object *obj)
     if (s->iothread) {
         colo_compare_timer_del(s);
     }
+
+    qemu_bh_delete(s->event_bh);
+
+    QTAILQ_FOREACH(tmp, &net_compares, next) {
+        if (tmp == s) {
+            QTAILQ_REMOVE(&net_compares, s, next);
+            break;
+        }
+    }
+
     /* Release all unhandled packets after compare thead exited */
     g_queue_foreach(&s->conn_list, colo_flush_packets, s);
 
@@ -1009,6 +1083,10 @@ static void colo_compare_finalize(Object *obj)
     if (s->iothread) {
         object_unref(OBJECT(s->iothread));
     }
+
+    qemu_mutex_destroy(&event_mtx);
+    qemu_cond_destroy(&event_complete_cond);
+
     g_free(s->pri_indev);
     g_free(s->sec_indev);
     g_free(s->outdev);
diff --git a/net/colo-compare.h b/net/colo-compare.h
new file mode 100644
index 0000000000..1b1ce76aea
--- /dev/null
+++ b/net/colo-compare.h
@@ -0,0 +1,22 @@
+/*
+ * COarse-grain LOck-stepping Virtual Machines for Non-stop Service (COLO)
+ * (a.k.a. Fault Tolerance or Continuous Replication)
+ *
+ * Copyright (c) 2017 HUAWEI TECHNOLOGIES CO., LTD.
+ * Copyright (c) 2017 FUJITSU LIMITED
+ * Copyright (c) 2017 Intel Corporation
+ *
+ * Authors:
+ *    zhanghailiang <zhang.zhanghailiang@huawei.com>
+ *    Zhang Chen <zhangckid@gmail.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.
+ */
+
+#ifndef QEMU_COLO_COMPARE_H
+#define QEMU_COLO_COMPARE_H
+
+void colo_notify_compares_event(void *opaque, int event, Error **errp);
+
+#endif /* QEMU_COLO_COMPARE_H */
-- 
2.17.GIT

[Qemu-devel] [PATCH V9 03/20] colo-compare: use notifier to notify packets comparing result

[Zhang Chen]

It's a good idea to use notifier to notify COLO frame of
inconsistent packets comparing.

Signed-off-by: Zhang Chen <zhangckid@gmail.com>
Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
---
 net/colo-compare.c | 37 ++++++++++++++++++++++++++-----------
 net/colo-compare.h |  2 ++
 2 files changed, 28 insertions(+), 11 deletions(-)

diff --git a/net/colo-compare.c b/net/colo-compare.c
index 80e6532e8b..426eab5973 100644
--- a/net/colo-compare.c
+++ b/net/colo-compare.c
@@ -29,6 +29,7 @@
 #include "sysemu/iothread.h"
 #include "net/colo-compare.h"
 #include "migration/colo.h"
+#include "migration/migration.h"
 
 #define TYPE_COLO_COMPARE "colo-compare"
 #define COLO_COMPARE(obj) \
@@ -37,6 +38,9 @@
 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
 
@@ -427,10 +431,7 @@ sec:
         qemu_hexdump((char *)spkt->data, stderr,
                      "colo-compare spkt", spkt->size);
 
-        /*
-         * colo_compare_inconsistent_notify();
-         * TODO: notice to checkpoint();
-         */
+        colo_compare_inconsistency_notify();
     }
 }
 
@@ -561,8 +562,24 @@ static int colo_old_packet_check_one(Packet *pkt, int64_t *check_time)
     }
 }
 
+static void colo_compare_inconsistency_notify(void)
+{
+    notifier_list_notify(&colo_compare_notifiers,
+                migrate_get_current());
+}
+
+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,
-                                          void *user_data)
+                                           void *user_data)
 {
     GList *result = NULL;
     int64_t check_time = REGULAR_PACKET_CHECK_MS;
@@ -573,10 +590,7 @@ static int colo_old_packet_check_one_conn(Connection *conn,
 
     if (result) {
         /* Do checkpoint will flush old packet */
-        /*
-         * TODO: Notify colo frame to do checkpoint.
-         * colo_compare_inconsistent_notify();
-         */
+        colo_compare_inconsistency_notify();
         return 0;
     }
 
@@ -620,11 +634,12 @@ static void colo_compare_packet(CompareState *s, Connection *conn,
             /*
              * If one packet arrive late, the secondary_list or
              * primary_list will be empty, so we can't compare it
-             * until next comparison.
+             * 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);
-            /* TODO: colo_notify_checkpoint();*/
+            colo_compare_inconsistency_notify();
             break;
         }
     }
diff --git a/net/colo-compare.h b/net/colo-compare.h
index 1b1ce76aea..22ddd512e2 100644
--- a/net/colo-compare.h
+++ b/net/colo-compare.h
@@ -18,5 +18,7 @@
 #define QEMU_COLO_COMPARE_H
 
 void colo_notify_compares_event(void *opaque, int event, Error **errp);
+void colo_compare_register_notifier(Notifier *notify);
+void colo_compare_unregister_notifier(Notifier *notify);
 
 #endif /* QEMU_COLO_COMPARE_H */
-- 
2.17.GIT

[Qemu-devel] [PATCH V9 04/20] COLO: integrate colo compare with colo frame

[Zhang Chen]

For COLO FT, both the PVM and SVM run at the same time,
only sync the state while it needs.

So here, let SVM runs while not doing checkpoint, change
DEFAULT_MIGRATE_X_CHECKPOINT_DELAY to 200*100.

Besides, we forgot to release colo_checkpoint_semd and
colo_delay_timer, fix them here.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Zhang Chen <zhangckid@gmail.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
 migration/colo.c      | 42 ++++++++++++++++++++++++++++++++++++++++--
 migration/migration.c |  6 ++----
 2 files changed, 42 insertions(+), 6 deletions(-)

diff --git a/migration/colo.c b/migration/colo.c
index 4381067ed4..081df1835f 100644
--- a/migration/colo.c
+++ b/migration/colo.c
@@ -25,8 +25,11 @@
 #include "qemu/error-report.h"
 #include "migration/failover.h"
 #include "replication.h"
+#include "net/colo-compare.h"
+#include "net/colo.h"
 
 static bool vmstate_loading;
+static Notifier packets_compare_notifier;
 
 #define COLO_BUFFER_BASE_SIZE (4 * 1024 * 1024)
 
@@ -343,6 +346,11 @@ static int colo_do_checkpoint_transaction(MigrationState *s,
         goto out;
     }
 
+    colo_notify_compares_event(NULL, COLO_EVENT_CHECKPOINT, &local_err);
+    if (local_err) {
+        goto out;
+    }
+
     /* Disable block migration */
     migrate_set_block_enabled(false, &local_err);
     qemu_savevm_state_header(fb);
@@ -400,6 +408,11 @@ out:
     return ret;
 }
 
+static void colo_compare_notify_checkpoint(Notifier *notifier, void *data)
+{
+    colo_checkpoint_notify(data);
+}
+
 static void colo_process_checkpoint(MigrationState *s)
 {
     QIOChannelBuffer *bioc;
@@ -416,6 +429,9 @@ static void colo_process_checkpoint(MigrationState *s)
         goto out;
     }
 
+    packets_compare_notifier.notify = colo_compare_notify_checkpoint;
+    colo_compare_register_notifier(&packets_compare_notifier);
+
     /*
      * Wait for Secondary finish loading VM states and enter COLO
      * restore.
@@ -461,11 +477,21 @@ out:
         qemu_fclose(fb);
     }
 
-    timer_del(s->colo_delay_timer);
-
     /* Hope this not to be too long to wait here */
     qemu_sem_wait(&s->colo_exit_sem);
     qemu_sem_destroy(&s->colo_exit_sem);
+
+    /*
+     * It is safe to unregister notifier after failover finished.
+     * Besides, colo_delay_timer and colo_checkpoint_sem can't be
+     * released befor unregister notifier, or there will be use-after-free
+     * error.
+     */
+    colo_compare_unregister_notifier(&packets_compare_notifier);
+    timer_del(s->colo_delay_timer);
+    timer_free(s->colo_delay_timer);
+    qemu_sem_destroy(&s->colo_checkpoint_sem);
+
     /*
      * Must be called after failover BH is completed,
      * Or the failover BH may shutdown the wrong fd that
@@ -558,6 +584,11 @@ void *colo_process_incoming_thread(void *opaque)
     fb = qemu_fopen_channel_input(QIO_CHANNEL(bioc));
     object_unref(OBJECT(bioc));
 
+    qemu_mutex_lock_iothread();
+    vm_start();
+    trace_colo_vm_state_change("stop", "run");
+    qemu_mutex_unlock_iothread();
+
     colo_send_message(mis->to_src_file, COLO_MESSAGE_CHECKPOINT_READY,
                       &local_err);
     if (local_err) {
@@ -577,6 +608,11 @@ void *colo_process_incoming_thread(void *opaque)
             goto out;
         }
 
+        qemu_mutex_lock_iothread();
+        vm_stop_force_state(RUN_STATE_COLO);
+        trace_colo_vm_state_change("run", "stop");
+        qemu_mutex_unlock_iothread();
+
         /* FIXME: This is unnecessary for periodic checkpoint mode */
         colo_send_message(mis->to_src_file, COLO_MESSAGE_CHECKPOINT_REPLY,
                      &local_err);
@@ -630,6 +666,8 @@ void *colo_process_incoming_thread(void *opaque)
         }
 
         vmstate_loading = false;
+        vm_start();
+        trace_colo_vm_state_change("stop", "run");
         qemu_mutex_unlock_iothread();
 
         if (failover_get_state() == FAILOVER_STATUS_RELAUNCH) {
diff --git a/migration/migration.c b/migration/migration.c
index e1eaa97df4..a4b478718f 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -75,10 +75,8 @@
 /* Migration XBZRLE default cache size */
 #define DEFAULT_MIGRATE_XBZRLE_CACHE_SIZE (64 * 1024 * 1024)
 
-/* The delay time (in ms) between two COLO checkpoints
- * Note: Please change this default value to 10000 when we support hybrid mode.
- */
-#define DEFAULT_MIGRATE_X_CHECKPOINT_DELAY 200
+/* The delay time (in ms) between two COLO checkpoints */
+#define DEFAULT_MIGRATE_X_CHECKPOINT_DELAY (200 * 100)
 #define DEFAULT_MIGRATE_MULTIFD_CHANNELS 2
 #define DEFAULT_MIGRATE_MULTIFD_PAGE_COUNT 16
 
-- 
2.17.GIT

[Qemu-devel] [PATCH V9 05/20] COLO: Add block replication into colo process

[Zhang Chen]

Make sure master start block replication after slave's block
replication started.

Besides, we need to activate VM's blocks before goes into
COLO state.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: Zhang Chen <zhangckid@gmail.com>
---
 migration/colo.c      | 43 +++++++++++++++++++++++++++++++++++++++++++
 migration/migration.c |  9 +++++++++
 2 files changed, 52 insertions(+)

diff --git a/migration/colo.c b/migration/colo.c
index 081df1835f..e06640c3d6 100644
--- a/migration/colo.c
+++ b/migration/colo.c
@@ -27,6 +27,7 @@
 #include "replication.h"
 #include "net/colo-compare.h"
 #include "net/colo.h"
+#include "block/block.h"
 
 static bool vmstate_loading;
 static Notifier packets_compare_notifier;
@@ -56,6 +57,7 @@ static void secondary_vm_do_failover(void)
 {
     int old_state;
     MigrationIncomingState *mis = migration_incoming_get_current();
+    Error *local_err = NULL;
 
     /* Can not do failover during the process of VM's loading VMstate, Or
      * it will break the secondary VM.
@@ -73,6 +75,11 @@ static void secondary_vm_do_failover(void)
     migrate_set_state(&mis->state, MIGRATION_STATUS_COLO,
                       MIGRATION_STATUS_COMPLETED);
 
+    replication_stop_all(true, &local_err);
+    if (local_err) {
+        error_report_err(local_err);
+    }
+
     if (!autostart) {
         error_report("\"-S\" qemu option will be ignored in secondary side");
         /* recover runstate to normal migration finish state */
@@ -110,6 +117,7 @@ static void primary_vm_do_failover(void)
 {
     MigrationState *s = migrate_get_current();
     int old_state;
+    Error *local_err = NULL;
 
     migrate_set_state(&s->state, MIGRATION_STATUS_COLO,
                       MIGRATION_STATUS_COMPLETED);
@@ -133,6 +141,13 @@ static void primary_vm_do_failover(void)
                      FailoverStatus_str(old_state));
         return;
     }
+
+    replication_stop_all(true, &local_err);
+    if (local_err) {
+        error_report_err(local_err);
+        local_err = NULL;
+    }
+
     /* Notify COLO thread that failover work is finished */
     qemu_sem_post(&s->colo_exit_sem);
 }
@@ -356,6 +371,11 @@ static int colo_do_checkpoint_transaction(MigrationState *s,
     qemu_savevm_state_header(fb);
     qemu_savevm_state_setup(fb);
     qemu_mutex_lock_iothread();
+    replication_do_checkpoint_all(&local_err);
+    if (local_err) {
+        qemu_mutex_unlock_iothread();
+        goto out;
+    }
     qemu_savevm_state_complete_precopy(fb, false, false);
     qemu_mutex_unlock_iothread();
 
@@ -446,6 +466,12 @@ static void colo_process_checkpoint(MigrationState *s)
     object_unref(OBJECT(bioc));
 
     qemu_mutex_lock_iothread();
+    replication_start_all(REPLICATION_MODE_PRIMARY, &local_err);
+    if (local_err) {
+        qemu_mutex_unlock_iothread();
+        goto out;
+    }
+
     vm_start();
     qemu_mutex_unlock_iothread();
     trace_colo_vm_state_change("stop", "run");
@@ -585,6 +611,11 @@ void *colo_process_incoming_thread(void *opaque)
     object_unref(OBJECT(bioc));
 
     qemu_mutex_lock_iothread();
+    replication_start_all(REPLICATION_MODE_SECONDARY, &local_err);
+    if (local_err) {
+        qemu_mutex_unlock_iothread();
+        goto out;
+    }
     vm_start();
     trace_colo_vm_state_change("stop", "run");
     qemu_mutex_unlock_iothread();
@@ -665,6 +696,18 @@ void *colo_process_incoming_thread(void *opaque)
             goto out;
         }
 
+        replication_get_error_all(&local_err);
+        if (local_err) {
+            qemu_mutex_unlock_iothread();
+            goto out;
+        }
+        /* discard colo disk buffer */
+        replication_do_checkpoint_all(&local_err);
+        if (local_err) {
+            qemu_mutex_unlock_iothread();
+            goto out;
+        }
+
         vmstate_loading = false;
         vm_start();
         trace_colo_vm_state_change("stop", "run");
diff --git a/migration/migration.c b/migration/migration.c
index a4b478718f..e665a1cab0 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -385,6 +385,7 @@ static void process_incoming_migration_co(void *opaque)
     MigrationIncomingState *mis = migration_incoming_get_current();
     PostcopyState ps;
     int ret;
+    Error *local_err = NULL;
 
     assert(mis->from_src_file);
     mis->largest_page_size = qemu_ram_pagesize_largest();
@@ -416,6 +417,14 @@ static void process_incoming_migration_co(void *opaque)
 
     /* we get COLO info, and know if we are in COLO mode */
     if (!ret && migration_incoming_enable_colo()) {
+        /* Make sure all file formats flush their mutable metadata */
+        bdrv_invalidate_cache_all(&local_err);
+        if (local_err) {
+            migrate_set_state(&mis->state, MIGRATION_STATUS_ACTIVE,
+                    MIGRATION_STATUS_FAILED);
+            error_report_err(local_err);
+            exit(EXIT_FAILURE);
+        }
         mis->migration_incoming_co = qemu_coroutine_self();
         qemu_thread_create(&mis->colo_incoming_thread, "COLO incoming",
              colo_process_incoming_thread, mis, QEMU_THREAD_JOINABLE);
-- 
2.17.GIT

[Qemu-devel] [PATCH V9 06/20] COLO: Remove colo_state migration struct

[Zhang Chen]

We need to know if migration is going into COLO state for
incoming side before start normal migration.

Instead by using the VMStateDescription to send colo_state
from source side to destination side, we use MIG_CMD_ENABLE_COLO
to indicate whether COLO is enabled or not.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Zhang Chen <zhangckid@gmail.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
 include/migration/colo.h |  5 +--
 migration/Makefile.objs  |  2 +-
 migration/colo-comm.c    | 76 ----------------------------------------
 migration/colo.c         | 13 ++++++-
 migration/migration.c    | 23 +++++++++++-
 migration/savevm.c       | 17 +++++++++
 migration/savevm.h       |  1 +
 migration/trace-events   |  1 +
 vl.c                     |  2 --
 9 files changed, 57 insertions(+), 83 deletions(-)
 delete mode 100644 migration/colo-comm.c

diff --git a/include/migration/colo.h b/include/migration/colo.h
index fefb2fcf4c..99ce17aca7 100644
--- a/include/migration/colo.h
+++ b/include/migration/colo.h
@@ -28,8 +28,9 @@ void migrate_start_colo_process(MigrationState *s);
 bool migration_in_colo_state(void);
 
 /* loadvm */
-bool migration_incoming_enable_colo(void);
-void migration_incoming_exit_colo(void);
+void migration_incoming_enable_colo(void);
+void migration_incoming_disable_colo(void);
+bool migration_incoming_colo_enabled(void);
 void *colo_process_incoming_thread(void *opaque);
 bool migration_incoming_in_colo_state(void);
 
diff --git a/migration/Makefile.objs b/migration/Makefile.objs
index c83ec47ba8..a4f3bafd86 100644
--- a/migration/Makefile.objs
+++ b/migration/Makefile.objs
@@ -1,6 +1,6 @@
 common-obj-y += migration.o socket.o fd.o exec.o
 common-obj-y += tls.o channel.o savevm.o
-common-obj-y += colo-comm.o colo.o colo-failover.o
+common-obj-y += colo.o colo-failover.o
 common-obj-y += vmstate.o vmstate-types.o page_cache.o
 common-obj-y += qemu-file.o global_state.o
 common-obj-y += qemu-file-channel.o
diff --git a/migration/colo-comm.c b/migration/colo-comm.c
deleted file mode 100644
index df26e4dfe7..0000000000
--- a/migration/colo-comm.c
+++ /dev/null
@@ -1,76 +0,0 @@
-/*
- * 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
- *
- * 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 "migration.h"
-#include "migration/colo.h"
-#include "migration/vmstate.h"
-#include "trace.h"
-
-typedef struct {
-     bool colo_requested;
-} COLOInfo;
-
-static COLOInfo colo_info;
-
-COLOMode get_colo_mode(void)
-{
-    if (migration_in_colo_state()) {
-        return COLO_MODE_PRIMARY;
-    } else if (migration_incoming_in_colo_state()) {
-        return COLO_MODE_SECONDARY;
-    } else {
-        return COLO_MODE_UNKNOWN;
-    }
-}
-
-static int colo_info_pre_save(void *opaque)
-{
-    COLOInfo *s = opaque;
-
-    s->colo_requested = migrate_colo_enabled();
-
-    return 0;
-}
-
-static bool colo_info_need(void *opaque)
-{
-   return migrate_colo_enabled();
-}
-
-static const VMStateDescription colo_state = {
-    .name = "COLOState",
-    .version_id = 1,
-    .minimum_version_id = 1,
-    .pre_save = colo_info_pre_save,
-    .needed = colo_info_need,
-    .fields = (VMStateField[]) {
-        VMSTATE_BOOL(colo_requested, COLOInfo),
-        VMSTATE_END_OF_LIST()
-    },
-};
-
-void colo_info_init(void)
-{
-    vmstate_register(NULL, 0, &colo_state, &colo_info);
-}
-
-bool migration_incoming_enable_colo(void)
-{
-    return colo_info.colo_requested;
-}
-
-void migration_incoming_exit_colo(void)
-{
-    colo_info.colo_requested = false;
-}
diff --git a/migration/colo.c b/migration/colo.c
index e06640c3d6..c083d3696f 100644
--- a/migration/colo.c
+++ b/migration/colo.c
@@ -152,6 +152,17 @@ static void primary_vm_do_failover(void)
     qemu_sem_post(&s->colo_exit_sem);
 }
 
+COLOMode get_colo_mode(void)
+{
+    if (migration_in_colo_state()) {
+        return COLO_MODE_PRIMARY;
+    } else if (migration_incoming_in_colo_state()) {
+        return COLO_MODE_SECONDARY;
+    } else {
+        return COLO_MODE_UNKNOWN;
+    }
+}
+
 void colo_do_failover(MigrationState *s)
 {
     /* Make sure VM stopped while failover happened. */
@@ -745,7 +756,7 @@ out:
     if (mis->to_src_file) {
         qemu_fclose(mis->to_src_file);
     }
-    migration_incoming_exit_colo();
+    migration_incoming_disable_colo();
 
     return NULL;
 }
diff --git a/migration/migration.c b/migration/migration.c
index e665a1cab0..d57a23dcfd 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -295,6 +295,22 @@ int migrate_send_rp_req_pages(MigrationIncomingState *mis, const char *rbname,
     return migrate_send_rp_message(mis, msg_type, msglen, bufc);
 }
 
+static bool migration_colo_enabled;
+bool migration_incoming_colo_enabled(void)
+{
+    return migration_colo_enabled;
+}
+
+void migration_incoming_disable_colo(void)
+{
+    migration_colo_enabled = false;
+}
+
+void migration_incoming_enable_colo(void)
+{
+    migration_colo_enabled = true;
+}
+
 void qemu_start_incoming_migration(const char *uri, Error **errp)
 {
     const char *p;
@@ -416,7 +432,7 @@ static void process_incoming_migration_co(void *opaque)
     }
 
     /* we get COLO info, and know if we are in COLO mode */
-    if (!ret && migration_incoming_enable_colo()) {
+    if (!ret && migration_incoming_colo_enabled()) {
         /* Make sure all file formats flush their mutable metadata */
         bdrv_invalidate_cache_all(&local_err);
         if (local_err) {
@@ -2906,6 +2922,11 @@ static void *migration_thread(void *opaque)
         qemu_savevm_send_postcopy_advise(s->to_dst_file);
     }
 
+    if (migrate_colo_enabled()) {
+        /* Notify migration destination that we enable COLO */
+        qemu_savevm_send_colo_enable(s->to_dst_file);
+    }
+
     qemu_savevm_state_setup(s->to_dst_file);
 
     s->setup_time = qemu_clock_get_ms(QEMU_CLOCK_HOST) - setup_start;
diff --git a/migration/savevm.c b/migration/savevm.c
index c2f34ffc7c..3e5b85636f 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -56,6 +56,7 @@
 #include "io/channel-file.h"
 #include "sysemu/replay.h"
 #include "qjson.h"
+#include "migration/colo.h"
 
 #ifndef ETH_P_RARP
 #define ETH_P_RARP 0x8035
@@ -83,6 +84,7 @@ enum qemu_vm_cmd {
                                       precopy but are dirty. */
     MIG_CMD_POSTCOPY_RESUME,       /* resume postcopy on dest */
     MIG_CMD_PACKAGED,          /* Send a wrapped stream within this stream */
+    MIG_CMD_ENABLE_COLO,       /* Enable COLO */
     MIG_CMD_RECV_BITMAP,       /* Request for recved bitmap on dst */
     MIG_CMD_MAX
 };
@@ -841,6 +843,12 @@ static void qemu_savevm_command_send(QEMUFile *f,
     qemu_fflush(f);
 }
 
+void qemu_savevm_send_colo_enable(QEMUFile *f)
+{
+    trace_savevm_send_colo_enable();
+    qemu_savevm_command_send(f, MIG_CMD_ENABLE_COLO, 0, NULL);
+}
+
 void qemu_savevm_send_ping(QEMUFile *f, uint32_t value)
 {
     uint32_t buf;
@@ -1918,6 +1926,12 @@ static int loadvm_handle_recv_bitmap(MigrationIncomingState *mis,
     return 0;
 }
 
+static int loadvm_process_enable_colo(MigrationIncomingState *mis)
+{
+    migration_incoming_enable_colo();
+    return 0;
+}
+
 /*
  * Process an incoming 'QEMU_VM_COMMAND'
  * 0           just a normal return
@@ -1997,6 +2011,9 @@ static int loadvm_process_command(QEMUFile *f)
 
     case MIG_CMD_RECV_BITMAP:
         return loadvm_handle_recv_bitmap(mis, len);
+
+    case MIG_CMD_ENABLE_COLO:
+        return loadvm_process_enable_colo(mis);
     }
 
     return 0;
diff --git a/migration/savevm.h b/migration/savevm.h
index a5e65b8ae3..8373c2f6bd 100644
--- a/migration/savevm.h
+++ b/migration/savevm.h
@@ -55,6 +55,7 @@ void qemu_savevm_send_postcopy_ram_discard(QEMUFile *f, const char *name,
                                            uint16_t len,
                                            uint64_t *start_list,
                                            uint64_t *length_list);
+void qemu_savevm_send_colo_enable(QEMUFile *f);
 
 int qemu_loadvm_state(QEMUFile *f);
 void qemu_loadvm_state_cleanup(void);
diff --git a/migration/trace-events b/migration/trace-events
index 3f67758893..86459d0580 100644
--- a/migration/trace-events
+++ b/migration/trace-events
@@ -37,6 +37,7 @@ savevm_send_ping(uint32_t val) "0x%x"
 savevm_send_postcopy_listen(void) ""
 savevm_send_postcopy_run(void) ""
 savevm_send_postcopy_resume(void) ""
+savevm_send_colo_enable(void) ""
 savevm_send_recv_bitmap(char *name) "%s"
 savevm_state_setup(void) ""
 savevm_state_resume_prepare(void) ""
diff --git a/vl.c b/vl.c
index d26f19b06d..33b723d075 100644
--- a/vl.c
+++ b/vl.c
@@ -4360,8 +4360,6 @@ int main(int argc, char **argv, char **envp)
 #endif
     }
 
-    colo_info_init();
-
     if (net_init_clients(&err) < 0) {
         error_report_err(err);
         exit(1);
-- 
2.17.GIT

[Qemu-devel] [PATCH V9 07/20] COLO: Load dirty pages into SVM's RAM cache firstly

[Zhang Chen]

We should not load PVM's state directly into SVM, because there maybe some
errors happen when SVM is receving data, which will break SVM.

We need to ensure receving all data before load the state into SVM. We use
an extra memory to cache these data (PVM's ram). The ram cache in secondary side
is initially the same as SVM/PVM's memory. And in the process of checkpoint,
we cache the dirty pages of PVM into this ram cache firstly, so this ram cache
always the same as PVM's memory at every checkpoint, then we flush this cached ram
to SVM after we receive all PVM's state.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: Zhang Chen <zhangckid@gmail.com>
---
 include/exec/ram_addr.h |  1 +
 migration/migration.c   |  6 +++
 migration/ram.c         | 83 ++++++++++++++++++++++++++++++++++++++++-
 migration/ram.h         |  4 ++
 migration/savevm.c      |  2 +-
 5 files changed, 93 insertions(+), 3 deletions(-)

diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h
index cf2446a176..51ec153a57 100644
--- a/include/exec/ram_addr.h
+++ b/include/exec/ram_addr.h
@@ -27,6 +27,7 @@ struct RAMBlock {
     struct rcu_head rcu;
     struct MemoryRegion *mr;
     uint8_t *host;
+    uint8_t *colo_cache; /* For colo, VM's ram cache */
     ram_addr_t offset;
     ram_addr_t used_length;
     ram_addr_t max_length;
diff --git a/migration/migration.c b/migration/migration.c
index d57a23dcfd..a17f81a245 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -441,6 +441,10 @@ static void process_incoming_migration_co(void *opaque)
             error_report_err(local_err);
             exit(EXIT_FAILURE);
         }
+        if (colo_init_ram_cache() < 0) {
+            error_report("Init ram cache failed");
+            exit(EXIT_FAILURE);
+        }
         mis->migration_incoming_co = qemu_coroutine_self();
         qemu_thread_create(&mis->colo_incoming_thread, "COLO incoming",
              colo_process_incoming_thread, mis, QEMU_THREAD_JOINABLE);
@@ -449,6 +453,8 @@ static void process_incoming_migration_co(void *opaque)
 
         /* Wait checkpoint incoming thread exit before free resource */
         qemu_thread_join(&mis->colo_incoming_thread);
+        /* We hold the global iothread lock, so it is safe here */
+        colo_release_ram_cache();
     }
 
     if (ret < 0) {
diff --git a/migration/ram.c b/migration/ram.c
index cd5f55117d..30cc83996f 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -2858,6 +2858,20 @@ static inline void *host_from_ram_block_offset(RAMBlock *block,
     return block->host + offset;
 }
 
+static inline void *colo_cache_from_block_offset(RAMBlock *block,
+                                                 ram_addr_t offset)
+{
+    if (!offset_in_ramblock(block, offset)) {
+        return NULL;
+    }
+    if (!block->colo_cache) {
+        error_report("%s: colo_cache is NULL in block :%s",
+                     __func__, block->idstr);
+        return NULL;
+    }
+    return block->colo_cache + offset;
+}
+
 /**
  * ram_handle_compressed: handle the zero page case
  *
@@ -3062,6 +3076,58 @@ static void decompress_data_with_multi_threads(QEMUFile *f,
     qemu_mutex_unlock(&decomp_done_lock);
 }
 
+/*
+ * colo cache: this is for secondary VM, we cache the whole
+ * memory of the secondary VM, it is need to hold the global lock
+ * to call this helper.
+ */
+int colo_init_ram_cache(void)
+{
+    RAMBlock *block;
+
+    rcu_read_lock();
+    QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
+        block->colo_cache = qemu_anon_ram_alloc(block->used_length,
+                                                NULL,
+                                                false);
+        if (!block->colo_cache) {
+            error_report("%s: Can't alloc memory for COLO cache of block %s,"
+                         "size 0x" RAM_ADDR_FMT, __func__, block->idstr,
+                         block->used_length);
+            goto out_locked;
+        }
+        memcpy(block->colo_cache, block->host, block->used_length);
+    }
+    rcu_read_unlock();
+    return 0;
+
+out_locked:
+    QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
+        if (block->colo_cache) {
+            qemu_anon_ram_free(block->colo_cache, block->used_length);
+            block->colo_cache = NULL;
+        }
+    }
+
+    rcu_read_unlock();
+    return -errno;
+}
+
+/* It is need to hold the global lock to call this helper */
+void colo_release_ram_cache(void)
+{
+    RAMBlock *block;
+
+    rcu_read_lock();
+    QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
+        if (block->colo_cache) {
+            qemu_anon_ram_free(block->colo_cache, block->used_length);
+            block->colo_cache = NULL;
+        }
+    }
+    rcu_read_unlock();
+}
+
 /**
  * ram_load_setup: Setup RAM for migration incoming side
  *
@@ -3078,6 +3144,7 @@ static int ram_load_setup(QEMUFile *f, void *opaque)
 
     xbzrle_load_setup();
     ramblock_recv_map_init();
+
     return 0;
 }
 
@@ -3091,6 +3158,7 @@ static int ram_load_cleanup(void *opaque)
         g_free(rb->receivedmap);
         rb->receivedmap = NULL;
     }
+
     return 0;
 }
 
@@ -3324,13 +3392,24 @@ static int ram_load(QEMUFile *f, void *opaque, int version_id)
                      RAM_SAVE_FLAG_COMPRESS_PAGE | RAM_SAVE_FLAG_XBZRLE)) {
             RAMBlock *block = ram_block_from_stream(f, flags);
 
-            host = host_from_ram_block_offset(block, addr);
+            /*
+             * After going into COLO, we should load the Page into colo_cache.
+             */
+            if (migration_incoming_in_colo_state()) {
+                host = colo_cache_from_block_offset(block, addr);
+            } else {
+                host = host_from_ram_block_offset(block, addr);
+            }
             if (!host) {
                 error_report("Illegal RAM offset " RAM_ADDR_FMT, addr);
                 ret = -EINVAL;
                 break;
             }
-            ramblock_recv_bitmap_set(block, host);
+
+            if (!migration_incoming_in_colo_state()) {
+                ramblock_recv_bitmap_set(block, host);
+            }
+
             trace_ram_load_loop(block->idstr, (uint64_t)addr, flags, host);
         }
 
diff --git a/migration/ram.h b/migration/ram.h
index d386f4d641..d5e81d4d48 100644
--- a/migration/ram.h
+++ b/migration/ram.h
@@ -70,4 +70,8 @@ int64_t ramblock_recv_bitmap_send(QEMUFile *file,
                                   const char *block_name);
 int ram_dirty_bitmap_reload(MigrationState *s, RAMBlock *rb);
 
+/* ram cache */
+int colo_init_ram_cache(void);
+void colo_release_ram_cache(void);
+
 #endif
diff --git a/migration/savevm.c b/migration/savevm.c
index 3e5b85636f..fe9ca86a78 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -1929,7 +1929,7 @@ static int loadvm_handle_recv_bitmap(MigrationIncomingState *mis,
 static int loadvm_process_enable_colo(MigrationIncomingState *mis)
 {
     migration_incoming_enable_colo();
-    return 0;
+    return colo_init_ram_cache();
 }
 
 /*
-- 
2.17.GIT

[Qemu-devel] [PATCH V9 08/20] ram/COLO: Record the dirty pages that SVM received

[Zhang Chen]

We record the address of the dirty pages that received,
it will help flushing pages that cached into SVM.

Here, it is a trick, we record dirty pages by re-using migration
dirty bitmap. In the later patch, we will start the dirty log
for SVM, just like migration, in this way, we can record both
the dirty pages caused by PVM and SVM, we only flush those dirty
pages from RAM cache while do checkpoint.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
 migration/ram.c | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/migration/ram.c b/migration/ram.c
index 30cc83996f..ecc5f46068 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -2869,6 +2869,15 @@ static inline void *colo_cache_from_block_offset(RAMBlock *block,
                      __func__, block->idstr);
         return NULL;
     }
+
+    /*
+    * During colo checkpoint, we need bitmap of these migrated pages.
+    * It help us to decide which pages in ram cache should be flushed
+    * into VM's RAM later.
+    */
+    if (!test_and_set_bit(offset >> TARGET_PAGE_BITS, block->bmap)) {
+        ram_state->migration_dirty_pages++;
+    }
     return block->colo_cache + offset;
 }
 
@@ -3099,6 +3108,24 @@ int colo_init_ram_cache(void)
         memcpy(block->colo_cache, block->host, block->used_length);
     }
     rcu_read_unlock();
+    /*
+    * Record the dirty pages that sent by PVM, we use this dirty bitmap together
+    * with to decide which page in cache should be flushed into SVM's RAM. Here
+    * we use the same name 'ram_bitmap' as for migration.
+    */
+    if (ram_bytes_total()) {
+        RAMBlock *block;
+
+        QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
+            unsigned long pages = block->max_length >> TARGET_PAGE_BITS;
+
+            block->bmap = bitmap_new(pages);
+            bitmap_set(block->bmap, 0, pages);
+         }
+    }
+    ram_state = g_new0(RAMState, 1);
+    ram_state->migration_dirty_pages = 0;
+
     return 0;
 
 out_locked:
@@ -3118,6 +3145,10 @@ void colo_release_ram_cache(void)
 {
     RAMBlock *block;
 
+    QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
+        g_free(block->bmap);
+        block->bmap = NULL;
+    }
     rcu_read_lock();
     QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
         if (block->colo_cache) {
@@ -3126,6 +3157,8 @@ void colo_release_ram_cache(void)
         }
     }
     rcu_read_unlock();
+    g_free(ram_state);
+    ram_state = NULL;
 }
 
 /**
-- 
2.17.GIT

[Qemu-devel] [PATCH V9 09/20] COLO: Flush memory data from ram cache

[Zhang Chen]

During the time of VM's running, PVM may dirty some pages, we will transfer
PVM's dirty pages to SVM and store them into SVM's RAM cache at next checkpoint
time. So, the content of SVM's RAM cache will always be same with PVM's memory
after checkpoint.

Instead of flushing all content of PVM's RAM cache into SVM's MEMORY,
we do this in a more efficient way:
Only flush any page that dirtied by PVM since last checkpoint.
In this way, we can ensure SVM's memory same with PVM's.

Besides, we must ensure flush RAM cache before load device state.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
 migration/ram.c        | 37 +++++++++++++++++++++++++++++++++++++
 migration/trace-events |  2 ++
 2 files changed, 39 insertions(+)

diff --git a/migration/ram.c b/migration/ram.c
index ecc5f46068..4199d64ebd 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -3370,6 +3370,39 @@ static bool postcopy_is_running(void)
     return ps >= POSTCOPY_INCOMING_LISTENING && ps < POSTCOPY_INCOMING_END;
 }
 
+/*
+ * Flush content of RAM cache into SVM's memory.
+ * Only flush the pages that be dirtied by PVM or SVM or both.
+ */
+static void colo_flush_ram_cache(void)
+{
+    RAMBlock *block = NULL;
+    void *dst_host;
+    void *src_host;
+    unsigned long offset = 0;
+
+    trace_colo_flush_ram_cache_begin(ram_state->migration_dirty_pages);
+    rcu_read_lock();
+    block = QLIST_FIRST_RCU(&ram_list.blocks);
+
+    while (block) {
+        offset = migration_bitmap_find_dirty(ram_state, block, offset);
+
+        if (offset << TARGET_PAGE_BITS >= block->used_length) {
+            offset = 0;
+            block = QLIST_NEXT_RCU(block, next);
+        } else {
+            migration_bitmap_clear_dirty(ram_state, block, offset);
+            dst_host = block->host + (offset << TARGET_PAGE_BITS);
+            src_host = block->colo_cache + (offset << TARGET_PAGE_BITS);
+            memcpy(dst_host, src_host, TARGET_PAGE_SIZE);
+        }
+    }
+
+    rcu_read_unlock();
+    trace_colo_flush_ram_cache_end();
+}
+
 static int ram_load(QEMUFile *f, void *opaque, int version_id)
 {
     int flags = 0, ret = 0, invalid_flags = 0;
@@ -3545,6 +3578,10 @@ static int ram_load(QEMUFile *f, void *opaque, int version_id)
     ret |= wait_for_decompress_done();
     rcu_read_unlock();
     trace_ram_load_complete(ret, seq_iter);
+
+    if (!ret  && migration_incoming_in_colo_state()) {
+        colo_flush_ram_cache();
+    }
     return ret;
 }
 
diff --git a/migration/trace-events b/migration/trace-events
index 86459d0580..6e1b58a6a3 100644
--- a/migration/trace-events
+++ b/migration/trace-events
@@ -90,6 +90,8 @@ ram_dirty_bitmap_sync_start(void) ""
 ram_dirty_bitmap_sync_wait(void) ""
 ram_dirty_bitmap_sync_complete(void) ""
 ram_state_resume_prepare(uint64_t v) "%" PRId64
+colo_flush_ram_cache_begin(uint64_t dirty_pages) "dirty_pages %" PRIu64
+colo_flush_ram_cache_end(void) ""
 
 # migration/migration.c
 await_return_path_close_on_source_close(void) ""
-- 
2.17.GIT

[Qemu-devel] [PATCH V9 10/20] qmp event: Add COLO_EXIT event to notify users while exited COLO

[Zhang Chen]

From: zhanghailiang <zhang.zhanghailiang@huawei.com>

If some errors happen during VM's COLO FT stage, it's important to
notify the users of this event. Together with 'x-colo-lost-heartbeat',
Users can intervene in COLO's failover work immediately.
If users don't want to get involved in COLO's failover verdict,
it is still necessary to notify users that we exited COLO mode.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: Zhang Chen <zhangckid@gmail.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
---
 migration/colo.c    | 31 +++++++++++++++++++++++++++++++
 qapi/migration.json | 38 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 69 insertions(+)

diff --git a/migration/colo.c b/migration/colo.c
index c083d3696f..ab484ad754 100644
--- a/migration/colo.c
+++ b/migration/colo.c
@@ -28,6 +28,7 @@
 #include "net/colo-compare.h"
 #include "net/colo.h"
 #include "block/block.h"
+#include "qapi/qapi-events-migration.h"
 
 static bool vmstate_loading;
 static Notifier packets_compare_notifier;
@@ -514,6 +515,23 @@ out:
         qemu_fclose(fb);
     }
 
+    /*
+     * There are only two reasons we can get here, some error happened
+     * or the user triggered failover.
+     */
+    switch (failover_get_state()) {
+    case FAILOVER_STATUS_NONE:
+        qapi_event_send_colo_exit(COLO_MODE_PRIMARY,
+                                  COLO_EXIT_REASON_ERROR, NULL);
+        break;
+    case FAILOVER_STATUS_REQUIRE:
+        qapi_event_send_colo_exit(COLO_MODE_PRIMARY,
+                                  COLO_EXIT_REASON_REQUEST, NULL);
+        break;
+    default:
+        abort();
+    }
+
     /* Hope this not to be too long to wait here */
     qemu_sem_wait(&s->colo_exit_sem);
     qemu_sem_destroy(&s->colo_exit_sem);
@@ -745,6 +763,19 @@ out:
         error_report_err(local_err);
     }
 
+    switch (failover_get_state()) {
+    case FAILOVER_STATUS_NONE:
+        qapi_event_send_colo_exit(COLO_MODE_SECONDARY,
+                                  COLO_EXIT_REASON_ERROR, NULL);
+        break;
+    case FAILOVER_STATUS_REQUIRE:
+        qapi_event_send_colo_exit(COLO_MODE_SECONDARY,
+                                  COLO_EXIT_REASON_REQUEST, NULL);
+        break;
+    default:
+        abort();
+    }
+
     if (fb) {
         qemu_fclose(fb);
     }
diff --git a/qapi/migration.json b/qapi/migration.json
index 1b4c1db670..d8c3b2e443 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -897,6 +897,44 @@
 { 'enum': 'FailoverStatus',
   'data': [ 'none', 'require', 'active', 'completed', 'relaunch' ] }
 
+##
+# @COLO_EXIT:
+#
+# Emitted when VM finishes COLO mode due to some errors happening or
+# at the request of users.
+#
+# @mode: report COLO mode when COLO exited.
+#
+# @reason: describes the reason for the COLO exit.
+#
+# Since: 3.0
+#
+# Example:
+#
+# <- { "timestamp": {"seconds": 2032141960, "microseconds": 417172},
+#      "event": "COLO_EXIT", "data": {"mode": "primary", "reason": "request" } }
+#
+##
+{ 'event': 'COLO_EXIT',
+  'data': {'mode': 'COLOMode', 'reason': 'COLOExitReason' } }
+
+##
+# @COLOExitReason:
+#
+# The reason for a COLO exit
+#
+# @none: no failover has ever happened. This can't occur in the
+# COLO_EXIT event, only in the result of query-colo-status.
+#
+# @request: COLO exit is due to an external request
+#
+# @error: COLO exit is due to an internal error
+#
+# Since: 3.0
+##
+{ 'enum': 'COLOExitReason',
+  'data': [ 'none', 'request', 'error' ] }
+
 ##
 # @x-colo-lost-heartbeat:
 #
-- 
2.17.GIT

[Qemu-devel] [PATCH V9 11/20] qapi/migration.json: Rename COLO unknown mode to none mode.

[Zhang Chen]

From: Zhang Chen <chen.zhang@intel.com>

Suggested by Markus Armbruster rename COLO unknown mode to none mode.

Signed-off-by: Zhang Chen <chen.zhang@intel.com>
---
 migration/colo-failover.c |  2 +-
 migration/colo.c          |  2 +-
 qapi/migration.json       | 10 +++++-----
 3 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/migration/colo-failover.c b/migration/colo-failover.c
index 0ae0c41221..4854a96c92 100644
--- a/migration/colo-failover.c
+++ b/migration/colo-failover.c
@@ -77,7 +77,7 @@ FailoverStatus failover_get_state(void)
 
 void qmp_x_colo_lost_heartbeat(Error **errp)
 {
-    if (get_colo_mode() == COLO_MODE_UNKNOWN) {
+    if (get_colo_mode() == COLO_MODE_NONE) {
         error_setg(errp, QERR_FEATURE_DISABLED, "colo");
         return;
     }
diff --git a/migration/colo.c b/migration/colo.c
index ab484ad754..8fdb79ac73 100644
--- a/migration/colo.c
+++ b/migration/colo.c
@@ -160,7 +160,7 @@ COLOMode get_colo_mode(void)
     } else if (migration_incoming_in_colo_state()) {
         return COLO_MODE_SECONDARY;
     } else {
-        return COLO_MODE_UNKNOWN;
+        return COLO_MODE_NONE;
     }
 }
 
diff --git a/qapi/migration.json b/qapi/migration.json
index d8c3b2e443..c24f114104 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -864,18 +864,18 @@
 ##
 # @COLOMode:
 #
-# The colo mode
+# The COLO current mode.
 #
-# @unknown: unknown mode
+# @none: None mode.
 #
-# @primary: master side
+# @primary: COLO node in primary side.
 #
-# @secondary: slave side
+# @secondary: COLO node in slave side.
 #
 # Since: 2.8
 ##
 { 'enum': 'COLOMode',
-  'data': [ 'unknown', 'primary', 'secondary'] }
+  'data': [ 'none', 'primary', 'secondary'] }
 
 ##
 # @FailoverStatus:
-- 
2.17.GIT

[Qemu-devel] [PATCH V9 12/20] qapi: Add new command to query colo status

[Zhang Chen]

Libvirt or other high level software can use this command query colo status.
You can test this command like that:
{'execute':'query-colo-status'}

Signed-off-by: Zhang Chen <zhangckid@gmail.com>
---
 migration/colo.c    | 39 +++++++++++++++++++++++++++++++++++++++
 qapi/migration.json | 34 ++++++++++++++++++++++++++++++++++
 2 files changed, 73 insertions(+)

diff --git a/migration/colo.c b/migration/colo.c
index 8fdb79ac73..eb21978bff 100644
--- a/migration/colo.c
+++ b/migration/colo.c
@@ -29,6 +29,7 @@
 #include "net/colo.h"
 #include "block/block.h"
 #include "qapi/qapi-events-migration.h"
+#include "qapi/qmp/qerror.h"
 
 static bool vmstate_loading;
 static Notifier packets_compare_notifier;
@@ -237,6 +238,44 @@ void qmp_xen_colo_do_checkpoint(Error **errp)
 #endif
 }
 
+COLOStatus *qmp_query_colo_status(Error **errp)
+{
+    int state;
+    COLOStatus *s = g_new0(COLOStatus, 1);
+
+    s->mode = get_colo_mode();
+
+    switch (s->mode) {
+    case COLO_MODE_NONE:
+        error_setg(errp, "COLO is disabled");
+        state = MIGRATION_STATUS_NONE;
+        break;
+    case COLO_MODE_PRIMARY:
+        state = migrate_get_current()->state;
+        break;
+    case COLO_MODE_SECONDARY:
+        state = migration_incoming_get_current()->state;
+        break;
+    default:
+        abort();
+    }
+
+    s->active = state == MIGRATION_STATUS_COLO;
+
+    switch (failover_get_state()) {
+    case FAILOVER_STATUS_NONE:
+        s->reason = COLO_EXIT_REASON_NONE;
+        break;
+    case FAILOVER_STATUS_REQUIRE:
+        s->reason = COLO_EXIT_REASON_REQUEST;
+        break;
+    default:
+        s->reason = COLO_EXIT_REASON_ERROR;
+    }
+
+    return s;
+}
+
 static void colo_send_message(QEMUFile *f, COLOMessage msg,
                               Error **errp)
 {
diff --git a/qapi/migration.json b/qapi/migration.json
index c24f114104..73c64686ec 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -1248,6 +1248,40 @@
 ##
 { 'command': 'xen-colo-do-checkpoint' }
 
+##
+# @COLOStatus:
+#
+# The result format for 'query-colo-status'.
+#
+# @mode: COLO running mode. If COLO is running, this field will return
+#        'primary' or 'secondary'.
+#
+# @active: true if COLO is active.
+#
+# @reason: describes the reason for the COLO exit.
+#
+# Since: 3.0
+##
+{ 'struct': 'COLOStatus',
+  'data': { 'mode': 'COLOMode', 'active': 'bool', 'reason': 'COLOExitReason' } }
+
+##
+# @query-colo-status:
+#
+# Query COLO status while the vm is running.
+#
+# Returns: A @COLOStatus object showing the status.
+#
+# Example:
+#
+# -> { "execute": "query-colo-status" }
+# <- { "return": { "mode": "primary", "active": true, "reason": "request" } }
+#
+# Since: 3.0
+##
+{ 'command': 'query-colo-status',
+  'returns': 'COLOStatus' }
+
 ##
 # @migrate-recover:
 #
-- 
2.17.GIT

[Qemu-devel] [PATCH V9 13/20] savevm: split the process of different stages for loadvm/savevm

[Zhang Chen]

There are several stages during loadvm/savevm process. In different stage,
migration incoming processes different types of sections.
We want to control these stages more accuracy, it will benefit COLO
performance, we don't have to save type of QEMU_VM_SECTION_START
sections everytime while do checkpoint, besides, we want to separate
the process of saving/loading memory and devices state.

So we add three new helper functions: qemu_load_device_state() and
qemu_savevm_live_state() to achieve different process during migration.

Besides, we make qemu_loadvm_state_main() and qemu_save_device_state()
public, and simplify the codes of qemu_save_device_state() by calling the
wrapper qemu_savevm_state_header().

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: Zhang Chen <zhangckid@gmail.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
 migration/colo.c   | 41 ++++++++++++++++++++++++++++++++---------
 migration/savevm.c | 36 +++++++++++++++++++++++++++++-------
 migration/savevm.h |  4 ++++
 3 files changed, 65 insertions(+), 16 deletions(-)

diff --git a/migration/colo.c b/migration/colo.c
index eb21978bff..a32c8e2244 100644
--- a/migration/colo.c
+++ b/migration/colo.c
@@ -30,6 +30,7 @@
 #include "block/block.h"
 #include "qapi/qapi-events-migration.h"
 #include "qapi/qmp/qerror.h"
+#include "sysemu/cpus.h"
 
 static bool vmstate_loading;
 static Notifier packets_compare_notifier;
@@ -419,23 +420,34 @@ static int colo_do_checkpoint_transaction(MigrationState *s,
 
     /* Disable block migration */
     migrate_set_block_enabled(false, &local_err);
-    qemu_savevm_state_header(fb);
-    qemu_savevm_state_setup(fb);
     qemu_mutex_lock_iothread();
     replication_do_checkpoint_all(&local_err);
     if (local_err) {
         qemu_mutex_unlock_iothread();
         goto out;
     }
-    qemu_savevm_state_complete_precopy(fb, false, false);
-    qemu_mutex_unlock_iothread();
-
-    qemu_fflush(fb);
 
     colo_send_message(s->to_dst_file, COLO_MESSAGE_VMSTATE_SEND, &local_err);
     if (local_err) {
+        qemu_mutex_unlock_iothread();
+        goto out;
+    }
+    /* Note: device state is saved into buffer */
+    ret = qemu_save_device_state(fb);
+
+    qemu_mutex_unlock_iothread();
+    if (ret < 0) {
         goto out;
     }
+    /*
+     * Only save VM's live state, which not including device state.
+     * TODO: We may need a timeout mechanism to prevent COLO process
+     * to be blocked here.
+     */
+    qemu_savevm_live_state(s->to_dst_file);
+
+    qemu_fflush(fb);
+
     /*
      * We need the size of the VMstate data in Secondary side,
      * With which we can decide how much data should be read.
@@ -653,6 +665,7 @@ void *colo_process_incoming_thread(void *opaque)
     uint64_t total_size;
     uint64_t value;
     Error *local_err = NULL;
+    int ret;
 
     qemu_sem_init(&mis->colo_incoming_sem, 0);
 
@@ -725,6 +738,16 @@ void *colo_process_incoming_thread(void *opaque)
             goto out;
         }
 
+        qemu_mutex_lock_iothread();
+        cpu_synchronize_all_pre_loadvm();
+        ret = qemu_loadvm_state_main(mis->from_src_file, mis);
+        qemu_mutex_unlock_iothread();
+
+        if (ret < 0) {
+            error_report("Load VM's live state (ram) error");
+            goto out;
+        }
+
         value = colo_receive_message_value(mis->from_src_file,
                                  COLO_MESSAGE_VMSTATE_SIZE, &local_err);
         if (local_err) {
@@ -756,10 +779,10 @@ void *colo_process_incoming_thread(void *opaque)
         }
 
         qemu_mutex_lock_iothread();
-        qemu_system_reset(SHUTDOWN_CAUSE_NONE);
         vmstate_loading = true;
-        if (qemu_loadvm_state(fb) < 0) {
-            error_report("COLO: loadvm failed");
+        ret = qemu_load_device_state(fb);
+        if (ret < 0) {
+            error_report("COLO: load device state failed");
             qemu_mutex_unlock_iothread();
             goto out;
         }
diff --git a/migration/savevm.c b/migration/savevm.c
index fe9ca86a78..036d030197 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -1378,13 +1378,21 @@ done:
     return ret;
 }
 
-static int qemu_save_device_state(QEMUFile *f)
+void qemu_savevm_live_state(QEMUFile *f)
 {
-    SaveStateEntry *se;
+    /* save QEMU_VM_SECTION_END section */
+    qemu_savevm_state_complete_precopy(f, true, false);
+    qemu_put_byte(f, QEMU_VM_EOF);
+}
 
-    qemu_put_be32(f, QEMU_VM_FILE_MAGIC);
-    qemu_put_be32(f, QEMU_VM_FILE_VERSION);
+int qemu_save_device_state(QEMUFile *f)
+{
+    SaveStateEntry *se;
 
+    if (!migration_in_colo_state()) {
+        qemu_put_be32(f, QEMU_VM_FILE_MAGIC);
+        qemu_put_be32(f, QEMU_VM_FILE_VERSION);
+    }
     cpu_synchronize_all_states();
 
     QTAILQ_FOREACH(se, &savevm_state.handlers, entry) {
@@ -1440,8 +1448,6 @@ enum LoadVMExitCodes {
     LOADVM_QUIT     =  1,
 };
 
-static int qemu_loadvm_state_main(QEMUFile *f, MigrationIncomingState *mis);
-
 /* ------ incoming postcopy messages ------ */
 /* 'advise' arrives before any transfers just to tell us that a postcopy
  * *might* happen - it might be skipped if precopy transferred everything
@@ -2241,7 +2247,7 @@ static bool postcopy_pause_incoming(MigrationIncomingState *mis)
     return true;
 }
 
-static int qemu_loadvm_state_main(QEMUFile *f, MigrationIncomingState *mis)
+int qemu_loadvm_state_main(QEMUFile *f, MigrationIncomingState *mis)
 {
     uint8_t section_type;
     int ret = 0;
@@ -2414,6 +2420,22 @@ int qemu_loadvm_state(QEMUFile *f)
     return ret;
 }
 
+int qemu_load_device_state(QEMUFile *f)
+{
+    MigrationIncomingState *mis = migration_incoming_get_current();
+    int ret;
+
+    /* Load QEMU_VM_SECTION_FULL section */
+    ret = qemu_loadvm_state_main(f, mis);
+    if (ret < 0) {
+        error_report("Failed to load device state: %d", ret);
+        return ret;
+    }
+
+    cpu_synchronize_all_post_init();
+    return 0;
+}
+
 int save_snapshot(const char *name, Error **errp)
 {
     BlockDriverState *bs, *bs1;
diff --git a/migration/savevm.h b/migration/savevm.h
index 8373c2f6bd..51a4b9caa8 100644
--- a/migration/savevm.h
+++ b/migration/savevm.h
@@ -56,8 +56,12 @@ void qemu_savevm_send_postcopy_ram_discard(QEMUFile *f, const char *name,
                                            uint64_t *start_list,
                                            uint64_t *length_list);
 void qemu_savevm_send_colo_enable(QEMUFile *f);
+void qemu_savevm_live_state(QEMUFile *f);
+int qemu_save_device_state(QEMUFile *f);
 
 int qemu_loadvm_state(QEMUFile *f);
 void qemu_loadvm_state_cleanup(void);
+int qemu_loadvm_state_main(QEMUFile *f, MigrationIncomingState *mis);
+int qemu_load_device_state(QEMUFile *f);
 
 #endif
-- 
2.17.GIT

[Qemu-devel] [PATCH V9 14/20] COLO: flush host dirty ram from cache

[Zhang Chen]

From: zhanghailiang <zhang.zhanghailiang@huawei.com>

Don't need to flush all VM's ram from cache, only
flush the dirty pages since last checkpoint

Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: Zhang Chen <zhangckid@gmail.com>
Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
 migration/ram.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/migration/ram.c b/migration/ram.c
index 4199d64ebd..fc0151cbfc 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -3125,6 +3125,7 @@ int colo_init_ram_cache(void)
     }
     ram_state = g_new0(RAMState, 1);
     ram_state->migration_dirty_pages = 0;
+    memory_global_dirty_log_start();
 
     return 0;
 
@@ -3145,10 +3146,12 @@ void colo_release_ram_cache(void)
 {
     RAMBlock *block;
 
+    memory_global_dirty_log_stop();
     QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
         g_free(block->bmap);
         block->bmap = NULL;
     }
+
     rcu_read_lock();
     QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
         if (block->colo_cache) {
@@ -3381,6 +3384,13 @@ static void colo_flush_ram_cache(void)
     void *src_host;
     unsigned long offset = 0;
 
+    memory_global_dirty_log_sync();
+    rcu_read_lock();
+    RAMBLOCK_FOREACH_MIGRATABLE(block) {
+        migration_bitmap_sync_range(ram_state, block, 0, block->used_length);
+    }
+    rcu_read_unlock();
+
     trace_colo_flush_ram_cache_begin(ram_state->migration_dirty_pages);
     rcu_read_lock();
     block = QLIST_FIRST_RCU(&ram_list.blocks);
-- 
2.17.GIT

[Qemu-devel] [PATCH V9 15/20] net/net.c: Add net client type check function for COLO

[Zhang Chen]

From: Zhang Chen <chen.zhang@intel.com>

We add is_colo_support_client_type() to check the net client type for
COLO-compare. Currently we just support TAP.
Suggested by Jason.

Signed-off-by: Zhang Chen <chen.zhang@intel.com>
---
 include/net/net.h  |  1 +
 net/colo-compare.c |  5 +++++
 net/net.c          | 14 ++++++++++++++
 3 files changed, 20 insertions(+)

diff --git a/include/net/net.h b/include/net/net.h
index 1425960f76..dcbc7ba9c0 100644
--- a/include/net/net.h
+++ b/include/net/net.h
@@ -212,6 +212,7 @@ void hmp_host_net_add(Monitor *mon, const QDict *qdict);
 void hmp_host_net_remove(Monitor *mon, const QDict *qdict);
 void netdev_add(QemuOpts *opts, Error **errp);
 void qmp_netdev_add(QDict *qdict, QObject **ret, Error **errp);
+bool is_colo_support_client_type(void);
 
 int net_hub_id_for_client(NetClientState *nc, int *id);
 NetClientState *net_hub_port_find(int hub_id);
diff --git a/net/colo-compare.c b/net/colo-compare.c
index 426eab5973..b8c0240725 100644
--- a/net/colo-compare.c
+++ b/net/colo-compare.c
@@ -996,6 +996,11 @@ static void colo_compare_complete(UserCreatable *uc, Error **errp)
         return;
     }
 
+    if (!is_colo_support_client_type()) {
+        error_setg(errp, "COLO-compare: Net client type is not supported");
+        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);
 
diff --git a/net/net.c b/net/net.c
index 2a3133990c..a77ea88fff 100644
--- a/net/net.c
+++ b/net/net.c
@@ -1733,3 +1733,17 @@ int net_fill_rstate(SocketReadState *rs, const uint8_t *buf, int size)
     assert(size == 0);
     return 0;
 }
+
+/* Currently, COLO just support TAP */
+bool is_colo_support_client_type(void)
+{
+    NetClientState *nc;
+
+    QTAILQ_FOREACH(nc, &net_clients, next) {
+        if (nc->info->type != NET_CLIENT_DRIVER_TAP) {
+            return false;
+        }
+    }
+
+    return true;
+}
-- 
2.17.GIT

[Qemu-devel] [PATCH V9 16/20] filter: Add handle_event method for NetFilterClass

[Zhang Chen]

Filter needs to process the event of checkpoint/failover or
other event passed by COLO frame.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
---
 include/net/filter.h |  5 +++++
 net/filter.c         | 17 +++++++++++++++++
 net/net.c            | 28 ++++++++++++++++++++++++++++
 3 files changed, 50 insertions(+)

diff --git a/include/net/filter.h b/include/net/filter.h
index 435acd6f82..49da666ac0 100644
--- a/include/net/filter.h
+++ b/include/net/filter.h
@@ -38,6 +38,8 @@ typedef ssize_t (FilterReceiveIOV)(NetFilterState *nc,
 
 typedef void (FilterStatusChanged) (NetFilterState *nf, Error **errp);
 
+typedef void (FilterHandleEvent) (NetFilterState *nf, int event, Error **errp);
+
 typedef struct NetFilterClass {
     ObjectClass parent_class;
 
@@ -45,6 +47,7 @@ typedef struct NetFilterClass {
     FilterSetup *setup;
     FilterCleanup *cleanup;
     FilterStatusChanged *status_changed;
+    FilterHandleEvent *handle_event;
     /* mandatory */
     FilterReceiveIOV *receive_iov;
 } NetFilterClass;
@@ -77,4 +80,6 @@ ssize_t qemu_netfilter_pass_to_next(NetClientState *sender,
                                     int iovcnt,
                                     void *opaque);
 
+void colo_notify_filters_event(int event, Error **errp);
+
 #endif /* QEMU_NET_FILTER_H */
diff --git a/net/filter.c b/net/filter.c
index 2fd7d7d663..0f17eba143 100644
--- a/net/filter.c
+++ b/net/filter.c
@@ -17,6 +17,8 @@
 #include "net/vhost_net.h"
 #include "qom/object_interfaces.h"
 #include "qemu/iov.h"
+#include "net/colo.h"
+#include "migration/colo.h"
 
 static inline bool qemu_can_skip_netfilter(NetFilterState *nf)
 {
@@ -245,11 +247,26 @@ static void netfilter_finalize(Object *obj)
     g_free(nf->netdev_id);
 }
 
+static void dummy_handle_event(NetFilterState *nf, int event, Error **errp)
+{
+    switch (event) {
+    case COLO_EVENT_CHECKPOINT:
+        break;
+    case COLO_EVENT_FAILOVER:
+        object_property_set_str(OBJECT(nf), "off", "status", errp);
+        break;
+    default:
+        break;
+    }
+}
+
 static void netfilter_class_init(ObjectClass *oc, void *data)
 {
     UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
+    NetFilterClass *nfc = NETFILTER_CLASS(oc);
 
     ucc->complete = netfilter_complete;
+    nfc->handle_event = dummy_handle_event;
 }
 
 static const TypeInfo netfilter_info = {
diff --git a/net/net.c b/net/net.c
index a77ea88fff..b4f6a2efb2 100644
--- a/net/net.c
+++ b/net/net.c
@@ -1331,6 +1331,34 @@ void hmp_info_network(Monitor *mon, const QDict *qdict)
     }
 }
 
+void colo_notify_filters_event(int event, Error **errp)
+{
+    NetClientState *nc, *peer;
+    NetClientDriver type;
+    NetFilterState *nf;
+    NetFilterClass *nfc = NULL;
+    Error *local_err = NULL;
+
+    QTAILQ_FOREACH(nc, &net_clients, next) {
+        peer = nc->peer;
+        type = nc->info->type;
+        if (!peer || type != NET_CLIENT_DRIVER_TAP) {
+            continue;
+        }
+        QTAILQ_FOREACH(nf, &nc->filters, next) {
+            nfc =  NETFILTER_GET_CLASS(OBJECT(nf));
+            if (!nfc->handle_event) {
+                continue;
+            }
+            nfc->handle_event(nf, event, &local_err);
+            if (local_err) {
+                error_propagate(errp, local_err);
+                return;
+            }
+        }
+    }
+}
+
 void qmp_set_link(const char *name, bool up, Error **errp)
 {
     NetClientState *ncs[MAX_QUEUE_NUM];
-- 
2.17.GIT

[Qemu-devel] [PATCH V9 17/20] filter-rewriter: handle checkpoint and failover event

[Zhang Chen]

After one round of checkpoint, the states between PVM and SVM
become consistent, so it is unnecessary to adjust the sequence
of net packets for old connections, besides, while failover
happens, filter-rewriter will into failover mode that needn't
handle the new TCP connection.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Zhang Chen <zhangckid@gmail.com>
---
 net/colo-compare.c    | 12 ++++-----
 net/colo.c            |  8 ++++++
 net/colo.h            |  2 ++
 net/filter-rewriter.c | 57 +++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 73 insertions(+), 6 deletions(-)

diff --git a/net/colo-compare.c b/net/colo-compare.c
index b8c0240725..462e822be6 100644
--- a/net/colo-compare.c
+++ b/net/colo-compare.c
@@ -116,6 +116,12 @@ enum {
     SECONDARY_IN,
 };
 
+static void colo_compare_inconsistency_notify(void)
+{
+    notifier_list_notify(&colo_compare_notifiers,
+                migrate_get_current());
+}
+
 static int compare_chr_send(CompareState *s,
                             const uint8_t *buf,
                             uint32_t size,
@@ -562,12 +568,6 @@ static int colo_old_packet_check_one(Packet *pkt, int64_t *check_time)
     }
 }
 
-static void colo_compare_inconsistency_notify(void)
-{
-    notifier_list_notify(&colo_compare_notifiers,
-                migrate_get_current());
-}
-
 void colo_compare_register_notifier(Notifier *notify)
 {
     notifier_list_add(&colo_compare_notifiers, notify);
diff --git a/net/colo.c b/net/colo.c
index 97c8fc928f..49176bf07b 100644
--- a/net/colo.c
+++ b/net/colo.c
@@ -221,3 +221,11 @@ Connection *connection_get(GHashTable *connection_track_table,
 
     return conn;
 }
+
+bool connection_has_tracked(GHashTable *connection_track_table,
+                            ConnectionKey *key)
+{
+    Connection *conn = g_hash_table_lookup(connection_track_table, key);
+
+    return conn ? true : false;
+}
diff --git a/net/colo.h b/net/colo.h
index 0277e0e9ba..11c5226488 100644
--- a/net/colo.h
+++ b/net/colo.h
@@ -98,6 +98,8 @@ void connection_destroy(void *opaque);
 Connection *connection_get(GHashTable *connection_track_table,
                            ConnectionKey *key,
                            GQueue *conn_list);
+bool connection_has_tracked(GHashTable *connection_track_table,
+                            ConnectionKey *key);
 void connection_hashtable_reset(GHashTable *connection_track_table);
 Packet *packet_new(const void *data, int size, int vnet_hdr_len);
 void packet_destroy(void *opaque, void *user_data);
diff --git a/net/filter-rewriter.c b/net/filter-rewriter.c
index f18a71bf2e..c463a0c1d0 100644
--- a/net/filter-rewriter.c
+++ b/net/filter-rewriter.c
@@ -20,11 +20,15 @@
 #include "qemu/main-loop.h"
 #include "qemu/iov.h"
 #include "net/checksum.h"
+#include "net/colo.h"
+#include "migration/colo.h"
 
 #define FILTER_COLO_REWRITER(obj) \
     OBJECT_CHECK(RewriterState, (obj), TYPE_FILTER_REWRITER)
 
 #define TYPE_FILTER_REWRITER "filter-rewriter"
+#define FAILOVER_MODE_ON  true
+#define FAILOVER_MODE_OFF false
 
 typedef struct RewriterState {
     NetFilterState parent_obj;
@@ -32,8 +36,14 @@ typedef struct RewriterState {
     /* hashtable to save connection */
     GHashTable *connection_track_table;
     bool vnet_hdr;
+    bool failover_mode;
 } RewriterState;
 
+static void filter_rewriter_failover_mode(RewriterState *s)
+{
+    s->failover_mode = FAILOVER_MODE_ON;
+}
+
 static void filter_rewriter_flush(NetFilterState *nf)
 {
     RewriterState *s = FILTER_COLO_REWRITER(nf);
@@ -269,6 +279,13 @@ static ssize_t colo_rewriter_receive_iov(NetFilterState *nf,
              */
             reverse_connection_key(&key);
         }
+
+        /* After failover we needn't change new TCP packet */
+        if (s->failover_mode &&
+            connection_has_tracked(s->connection_track_table, &key)) {
+            goto out;
+        }
+
         conn = connection_get(s->connection_track_table,
                               &key,
                               NULL);
@@ -302,11 +319,49 @@ static ssize_t colo_rewriter_receive_iov(NetFilterState *nf,
         }
     }
 
+out:
     packet_destroy(pkt, NULL);
     pkt = NULL;
     return 0;
 }
 
+static void reset_seq_offset(gpointer key, gpointer value, gpointer user_data)
+{
+    Connection *conn = (Connection *)value;
+
+    conn->offset = 0;
+}
+
+static gboolean offset_is_nonzero(gpointer key,
+                                  gpointer value,
+                                  gpointer user_data)
+{
+    Connection *conn = (Connection *)value;
+
+    return conn->offset ? true : false;
+}
+
+static void colo_rewriter_handle_event(NetFilterState *nf, int event,
+                                       Error **errp)
+{
+    RewriterState *rs = FILTER_COLO_REWRITER(nf);
+
+    switch (event) {
+    case COLO_EVENT_CHECKPOINT:
+        g_hash_table_foreach(rs->connection_track_table,
+                            reset_seq_offset, NULL);
+        break;
+    case COLO_EVENT_FAILOVER:
+        if (!g_hash_table_find(rs->connection_track_table,
+                              offset_is_nonzero, NULL)) {
+            filter_rewriter_failover_mode(rs);
+        }
+        break;
+    default:
+        break;
+    }
+}
+
 static void colo_rewriter_cleanup(NetFilterState *nf)
 {
     RewriterState *s = FILTER_COLO_REWRITER(nf);
@@ -350,6 +405,7 @@ static void filter_rewriter_init(Object *obj)
     RewriterState *s = FILTER_COLO_REWRITER(obj);
 
     s->vnet_hdr = false;
+    s->failover_mode = FAILOVER_MODE_OFF;
     object_property_add_bool(obj, "vnet_hdr_support",
                              filter_rewriter_get_vnet_hdr,
                              filter_rewriter_set_vnet_hdr, NULL);
@@ -362,6 +418,7 @@ static void colo_rewriter_class_init(ObjectClass *oc, void *data)
     nfc->setup = colo_rewriter_setup;
     nfc->cleanup = colo_rewriter_cleanup;
     nfc->receive_iov = colo_rewriter_receive_iov;
+    nfc->handle_event = colo_rewriter_handle_event;
 }
 
 static const TypeInfo colo_rewriter_info = {
-- 
2.17.GIT

[Qemu-devel] [PATCH V9 18/20] COLO: notify net filters about checkpoint/failover event

[Zhang Chen]

From: zhanghailiang <zhang.zhanghailiang@huawei.com>

Notify all net filters about the checkpoint and failover event.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
 migration/colo.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/migration/colo.c b/migration/colo.c
index a32c8e2244..4d0ee7d8aa 100644
--- a/migration/colo.c
+++ b/migration/colo.c
@@ -31,6 +31,7 @@
 #include "qapi/qapi-events-migration.h"
 #include "qapi/qmp/qerror.h"
 #include "sysemu/cpus.h"
+#include "net/filter.h"
 
 static bool vmstate_loading;
 static Notifier packets_compare_notifier;
@@ -83,6 +84,12 @@ static void secondary_vm_do_failover(void)
         error_report_err(local_err);
     }
 
+    /* Notify all filters of all NIC to do checkpoint */
+    colo_notify_filters_event(COLO_EVENT_FAILOVER, &local_err);
+    if (local_err) {
+        error_report_err(local_err);
+    }
+
     if (!autostart) {
         error_report("\"-S\" qemu option will be ignored in secondary side");
         /* recover runstate to normal migration finish state */
@@ -799,6 +806,14 @@ void *colo_process_incoming_thread(void *opaque)
             goto out;
         }
 
+        /* Notify all filters of all NIC to do checkpoint */
+        colo_notify_filters_event(COLO_EVENT_CHECKPOINT, &local_err);
+
+        if (local_err) {
+            qemu_mutex_unlock_iothread();
+            goto out;
+        }
+
         vmstate_loading = false;
         vm_start();
         trace_colo_vm_state_change("stop", "run");
-- 
2.17.GIT

[Qemu-devel] [PATCH V9 19/20] COLO: quick failover process by kick COLO thread

[Zhang Chen]

From: zhanghailiang <zhang.zhanghailiang@huawei.com>

COLO thread may sleep at qemu_sem_wait(&s->colo_checkpoint_sem),
while failover works begin, It's better to wakeup it to quick
the process.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
 migration/colo.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/migration/colo.c b/migration/colo.c
index 4d0ee7d8aa..553b28adbb 100644
--- a/migration/colo.c
+++ b/migration/colo.c
@@ -131,6 +131,11 @@ static void primary_vm_do_failover(void)
 
     migrate_set_state(&s->state, MIGRATION_STATUS_COLO,
                       MIGRATION_STATUS_COMPLETED);
+    /*
+     * kick COLO thread which might wait at
+     * qemu_sem_wait(&s->colo_checkpoint_sem).
+     */
+    colo_checkpoint_notify(migrate_get_current());
 
     /*
      * Wake up COLO thread which may blocked in recv() or send(),
@@ -557,6 +562,9 @@ static void colo_process_checkpoint(MigrationState *s)
 
         qemu_sem_wait(&s->colo_checkpoint_sem);
 
+        if (s->state != MIGRATION_STATUS_COLO) {
+            goto out;
+        }
         ret = colo_do_checkpoint_transaction(s, bioc, fb);
         if (ret < 0) {
             goto out;
-- 
2.17.GIT

[Qemu-devel] [PATCH V9 20/20] docs: Add COLO status diagram to COLO-FT.txt

[Zhang Chen]

From: Zhang Chen <chen.zhang@intel.com>

This diagram make user better understand COLO.
Suggested by Markus Armbruster.

Signed-off-by: Zhang Chen <chen.zhang@intel.com>
---
 docs/COLO-FT.txt | 34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/docs/COLO-FT.txt b/docs/COLO-FT.txt
index e289be2f41..caa68f0a9a 100644
--- a/docs/COLO-FT.txt
+++ b/docs/COLO-FT.txt
@@ -110,6 +110,40 @@ Note:
 HeartBeat has not been implemented yet, so you need to trigger failover process
 by using 'x-colo-lost-heartbeat' command.
 
+== COLO operation status ==
+
++-----------------+
+|                 |
+|    Start COLO   |
+|                 |
++--------+--------+
+         |
+         |  Main qmp command:
+         |  migrate-set-capabilities with x-colo
+         |  migrate
+         |
+         v
++--------+--------+
+|                 |
+|  COLO running   |
+|                 |
++--------+--------+
+         |
+         |  Main qmp command:
+         |  x-colo-lost-heartbeat
+         |  or
+         |  some error happened
+         v
++--------+--------+
+|                 |  send qmp event:
+|  COLO failover  |  COLO_EXIT
+|                 |
++-----------------+
+
+COLO use the qmp command switching and report operation status.
+The diagram just write the main qmp command, you can get the detail
+in test procedure.
+
 == Test procedure ==
 1. Startup qemu
 Primary:
-- 
2.17.GIT

Re: [Qemu-devel] [PATCH V9 11/20] qapi/migration.json: Rename COLO unknown mode to none mode.

[Eric Blake]

On 06/27/2018 03:41 PM, Zhang Chen wrote:
> From: Zhang Chen <chen.zhang@intel.com>
> 
> Suggested by Markus Armbruster rename COLO unknown mode to none mode.
> 
> Signed-off-by: Zhang Chen <chen.zhang@intel.com>
> ---
>   migration/colo-failover.c |  2 +-
>   migration/colo.c          |  2 +-
>   qapi/migration.json       | 10 +++++-----
>   3 files changed, 7 insertions(+), 7 deletions(-)

>   # Since: 2.8
>   ##
>   { 'enum': 'COLOMode',
> -  'data': [ 'unknown', 'primary', 'secondary'] }
> +  'data': [ 'none', 'primary', 'secondary'] }

The deletion of 'unknown' could potentially be a user-visible regression 
visible if COLOMode were in a QMP command; but thankfully the generated 
qapi/qapi-introspect.c does not seem to cover this enum, so it just 
affects internal code for now.

Reviewed-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org

Re: [Qemu-devel] [PATCH V9 11/20] qapi/migration.json: Rename COLO unknown mode to none mode.

[Dr. David Alan Gilbert]

* Eric Blake (eblake@redhat.com) wrote:
> On 06/27/2018 03:41 PM, Zhang Chen wrote:
> > From: Zhang Chen <chen.zhang@intel.com>
> > 
> > Suggested by Markus Armbruster rename COLO unknown mode to none mode.
> > 
> > Signed-off-by: Zhang Chen <chen.zhang@intel.com>
> > ---
> >   migration/colo-failover.c |  2 +-
> >   migration/colo.c          |  2 +-
> >   qapi/migration.json       | 10 +++++-----
> >   3 files changed, 7 insertions(+), 7 deletions(-)
> 
> >   # Since: 2.8
> >   ##
> >   { 'enum': 'COLOMode',
> > -  'data': [ 'unknown', 'primary', 'secondary'] }
> > +  'data': [ 'none', 'primary', 'secondary'] }
> 
> The deletion of 'unknown' could potentially be a user-visible regression
> visible if COLOMode were in a QMP command; but thankfully the generated
> qapi/qapi-introspect.c does not seem to cover this enum, so it just affects
> internal code for now.

Note that the migration capability to enable colo is still x-colo;
so I take that to mean we've still got a free hand to change any part of
the COLO interface until we're happy it's right.

Dave

> Reviewed-by: Eric Blake <eblake@redhat.com>
> 
> -- 
> Eric Blake, Principal Software Engineer
> Red Hat, Inc.           +1-919-301-3266
> Virtualization:  qemu.org | libvirt.org
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK

Re: [Qemu-devel] [PATCH V9 11/20] qapi/migration.json: Rename COLO unknown mode to none mode.

[Zhang Chen]

On Fri, Jun 29, 2018 at 5:14 PM, Dr. David Alan Gilbert <dgilbert@redhat.com
> wrote:

> * Eric Blake (eblake@redhat.com) wrote:
> > On 06/27/2018 03:41 PM, Zhang Chen wrote:
> > > From: Zhang Chen <chen.zhang@intel.com>
> > >
> > > Suggested by Markus Armbruster rename COLO unknown mode to none mode.
> > >
> > > Signed-off-by: Zhang Chen <chen.zhang@intel.com>
> > > ---
> > >   migration/colo-failover.c |  2 +-
> > >   migration/colo.c          |  2 +-
> > >   qapi/migration.json       | 10 +++++-----
> > >   3 files changed, 7 insertions(+), 7 deletions(-)
> >
> > >   # Since: 2.8
> > >   ##
> > >   { 'enum': 'COLOMode',
> > > -  'data': [ 'unknown', 'primary', 'secondary'] }
> > > +  'data': [ 'none', 'primary', 'secondary'] }
> >
> > The deletion of 'unknown' could potentially be a user-visible regression
> > visible if COLOMode were in a QMP command; but thankfully the generated
> > qapi/qapi-introspect.c does not seem to cover this enum, so it just
> affects
> > internal code for now.
>
> Note that the migration capability to enable colo is still x-colo;
> so I take that to mean we've still got a free hand to change any part of
> the COLO interface until we're happy it's right.
>
> Dave
>
>
Thanks Eric and Dave.

Zhang Chen



> > Reviewed-by: Eric Blake <eblake@redhat.com>
> >
> > --
> > Eric Blake, Principal Software Engineer
> > Red Hat, Inc.           +1-919-301-3266
> > Virtualization:  qemu.org | libvirt.org
> --
> Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
>

Re: [Qemu-devel] [PATCH V9 11/20] qapi/migration.json: Rename COLO unknown mode to none mode.

[Markus Armbruster]

Zhang Chen <zhangckid@gmail.com> writes:

> From: Zhang Chen <chen.zhang@intel.com>
>
> Suggested by Markus Armbruster rename COLO unknown mode to none mode.
>
> Signed-off-by: Zhang Chen <chen.zhang@intel.com>
> ---
>  migration/colo-failover.c |  2 +-
>  migration/colo.c          |  2 +-
>  qapi/migration.json       | 10 +++++-----
>  3 files changed, 7 insertions(+), 7 deletions(-)
>
> diff --git a/migration/colo-failover.c b/migration/colo-failover.c
> index 0ae0c41221..4854a96c92 100644
> --- a/migration/colo-failover.c
> +++ b/migration/colo-failover.c
> @@ -77,7 +77,7 @@ FailoverStatus failover_get_state(void)
>  
>  void qmp_x_colo_lost_heartbeat(Error **errp)
>  {
> -    if (get_colo_mode() == COLO_MODE_UNKNOWN) {
> +    if (get_colo_mode() == COLO_MODE_NONE) {
>          error_setg(errp, QERR_FEATURE_DISABLED, "colo");
>          return;
>      }
> diff --git a/migration/colo.c b/migration/colo.c
> index ab484ad754..8fdb79ac73 100644
> --- a/migration/colo.c
> +++ b/migration/colo.c
> @@ -160,7 +160,7 @@ COLOMode get_colo_mode(void)
>      } else if (migration_incoming_in_colo_state()) {
>          return COLO_MODE_SECONDARY;
>      } else {
> -        return COLO_MODE_UNKNOWN;
> +        return COLO_MODE_NONE;
>      }
>  }
>  
> diff --git a/qapi/migration.json b/qapi/migration.json
> index d8c3b2e443..c24f114104 100644
> --- a/qapi/migration.json
> +++ b/qapi/migration.json
> @@ -864,18 +864,18 @@
>  ##
>  # @COLOMode:
>  #
> -# The colo mode
> +# The COLO current mode.
>  #
> -# @unknown: unknown mode
> +# @none: None mode.

This could use a bit of polish.  Perhaps:

   # @none: COLO is disabled.

>  #
> -# @primary: master side
> +# @primary: COLO node in primary side.
>  #
> -# @secondary: slave side
> +# @secondary: COLO node in slave side.
>  #
>  # Since: 2.8
>  ##
>  { 'enum': 'COLOMode',
> -  'data': [ 'unknown', 'primary', 'secondary'] }
> +  'data': [ 'none', 'primary', 'secondary'] }
>  
>  ##
>  # @FailoverStatus:

Preferably with the comment improved:
Reviewed-by: Markus Armbruster <armbru@redhat.com>

Re: [Qemu-devel] [PATCH V9 12/20] qapi: Add new command to query colo status

[Markus Armbruster]

Zhang Chen <zhangckid@gmail.com> writes:

> Libvirt or other high level software can use this command query colo status.
> You can test this command like that:
> {'execute':'query-colo-status'}
>
> Signed-off-by: Zhang Chen <zhangckid@gmail.com>
> ---
>  migration/colo.c    | 39 +++++++++++++++++++++++++++++++++++++++
>  qapi/migration.json | 34 ++++++++++++++++++++++++++++++++++
>  2 files changed, 73 insertions(+)
>
> diff --git a/migration/colo.c b/migration/colo.c
> index 8fdb79ac73..eb21978bff 100644
> --- a/migration/colo.c
> +++ b/migration/colo.c
> @@ -29,6 +29,7 @@
>  #include "net/colo.h"
>  #include "block/block.h"
>  #include "qapi/qapi-events-migration.h"
> +#include "qapi/qmp/qerror.h"
>  
>  static bool vmstate_loading;
>  static Notifier packets_compare_notifier;
> @@ -237,6 +238,44 @@ void qmp_xen_colo_do_checkpoint(Error **errp)
>  #endif
>  }
>  
> +COLOStatus *qmp_query_colo_status(Error **errp)
> +{
> +    int state;
> +    COLOStatus *s = g_new0(COLOStatus, 1);
> +
> +    s->mode = get_colo_mode();
> +
> +    switch (s->mode) {
> +    case COLO_MODE_NONE:
> +        error_setg(errp, "COLO is disabled");
> +        state = MIGRATION_STATUS_NONE;
> +        break;
> +    case COLO_MODE_PRIMARY:
> +        state = migrate_get_current()->state;
> +        break;
> +    case COLO_MODE_SECONDARY:
> +        state = migration_incoming_get_current()->state;
> +        break;
> +    default:
> +        abort();
> +    }
> +
> +    s->active = state == MIGRATION_STATUS_COLO;
> +
> +    switch (failover_get_state()) {
> +    case FAILOVER_STATUS_NONE:
> +        s->reason = COLO_EXIT_REASON_NONE;
> +        break;
> +    case FAILOVER_STATUS_REQUIRE:
> +        s->reason = COLO_EXIT_REASON_REQUEST;
> +        break;
> +    default:
> +        s->reason = COLO_EXIT_REASON_ERROR;
> +    }
> +
> +    return s;
> +}
> +
>  static void colo_send_message(QEMUFile *f, COLOMessage msg,
>                                Error **errp)
>  {
> diff --git a/qapi/migration.json b/qapi/migration.json
> index c24f114104..73c64686ec 100644
> --- a/qapi/migration.json
> +++ b/qapi/migration.json
> @@ -1248,6 +1248,40 @@
>  ##
>  { 'command': 'xen-colo-do-checkpoint' }
>  
> +##
> +# @COLOStatus:
> +#
> +# The result format for 'query-colo-status'.
> +#
> +# @mode: COLO running mode. If COLO is running, this field will return
> +#        'primary' or 'secondary'.

Please mention that @mode is "none" when COLO is not running.

> +#
> +# @active: true if COLO is active.

Please use consistent terminology: pick one of "COLO is running", "COLO
is active" and stick to it.  v8 had that here, v9 regressed.  Also use
this wording for the comment improvement I requested for PATCH 11.

However, isn't @active redundant with @mode?

> +#
> +# @reason: describes the reason for the COLO exit.
> +#
> +# Since: 3.0
> +##
> +{ 'struct': 'COLOStatus',
> +  'data': { 'mode': 'COLOMode', 'active': 'bool', 'reason': 'COLOExitReason' } }
> +
> +##
> +# @query-colo-status:
> +#
> +# Query COLO status while the vm is running.
> +#
> +# Returns: A @COLOStatus object showing the status.
> +#
> +# Example:
> +#
> +# -> { "execute": "query-colo-status" }
> +# <- { "return": { "mode": "primary", "active": true, "reason": "request" } }
> +#
> +# Since: 3.0
> +##
> +{ 'command': 'query-colo-status',
> +  'returns': 'COLOStatus' }
> +
>  ##
>  # @migrate-recover:
>  #

Re: [Qemu-devel] [PATCH V9 12/20] qapi: Add new command to query colo status

[Zhang Chen]

On Tue, Jul 3, 2018 at 7:09 PM, Markus Armbruster <armbru@redhat.com> wrote:

> Zhang Chen <zhangckid@gmail.com> writes:
>
> > Libvirt or other high level software can use this command query colo
> status.
> > You can test this command like that:
> > {'execute':'query-colo-status'}
> >
> > Signed-off-by: Zhang Chen <zhangckid@gmail.com>
> > ---
> >  migration/colo.c    | 39 +++++++++++++++++++++++++++++++++++++++
> >  qapi/migration.json | 34 ++++++++++++++++++++++++++++++++++
> >  2 files changed, 73 insertions(+)
> >
> > diff --git a/migration/colo.c b/migration/colo.c
> > index 8fdb79ac73..eb21978bff 100644
> > --- a/migration/colo.c
> > +++ b/migration/colo.c
> > @@ -29,6 +29,7 @@
> >  #include "net/colo.h"
> >  #include "block/block.h"
> >  #include "qapi/qapi-events-migration.h"
> > +#include "qapi/qmp/qerror.h"
> >
> >  static bool vmstate_loading;
> >  static Notifier packets_compare_notifier;
> > @@ -237,6 +238,44 @@ void qmp_xen_colo_do_checkpoint(Error **errp)
> >  #endif
> >  }
> >
> > +COLOStatus *qmp_query_colo_status(Error **errp)
> > +{
> > +    int state;
> > +    COLOStatus *s = g_new0(COLOStatus, 1);
> > +
> > +    s->mode = get_colo_mode();
> > +
> > +    switch (s->mode) {
> > +    case COLO_MODE_NONE:
> > +        error_setg(errp, "COLO is disabled");
> > +        state = MIGRATION_STATUS_NONE;
> > +        break;
> > +    case COLO_MODE_PRIMARY:
> > +        state = migrate_get_current()->state;
> > +        break;
> > +    case COLO_MODE_SECONDARY:
> > +        state = migration_incoming_get_current()->state;
> > +        break;
> > +    default:
> > +        abort();
> > +    }
> > +
> > +    s->active = state == MIGRATION_STATUS_COLO;
> > +
> > +    switch (failover_get_state()) {
> > +    case FAILOVER_STATUS_NONE:
> > +        s->reason = COLO_EXIT_REASON_NONE;
> > +        break;
> > +    case FAILOVER_STATUS_REQUIRE:
> > +        s->reason = COLO_EXIT_REASON_REQUEST;
> > +        break;
> > +    default:
> > +        s->reason = COLO_EXIT_REASON_ERROR;
> > +    }
> > +
> > +    return s;
> > +}
> > +
> >  static void colo_send_message(QEMUFile *f, COLOMessage msg,
> >                                Error **errp)
> >  {
> > diff --git a/qapi/migration.json b/qapi/migration.json
> > index c24f114104..73c64686ec 100644
> > --- a/qapi/migration.json
> > +++ b/qapi/migration.json
> > @@ -1248,6 +1248,40 @@
> >  ##
> >  { 'command': 'xen-colo-do-checkpoint' }
> >
> > +##
> > +# @COLOStatus:
> > +#
> > +# The result format for 'query-colo-status'.
> > +#
> > +# @mode: COLO running mode. If COLO is running, this field will return
> > +#        'primary' or 'secondary'.
>
> Please mention that @mode is "none" when COLO is not running.
>

OK.


>
> > +#
> > +# @active: true if COLO is active.
>
> Please use consistent terminology: pick one of "COLO is running", "COLO
> is active" and stick to it.  v8 had that here, v9 regressed.  Also use
> this wording for the comment improvement I requested for PATCH 11.
>
> However, isn't @active redundant with @mode?
>
>
I re-think about this and review the codes.
The 'none' mode can cover this field, I will remove the @active in next
version.
By the way, can you review the diagram patch as your comments?
(have some action not related to qmp, so I just drew a general diagram.)

Thanks
Zhang Chen



> > +#
> > +# @reason: describes the reason for the COLO exit.
> > +#
> > +# Since: 3.0
> > +##
> > +{ 'struct': 'COLOStatus',
> > +  'data': { 'mode': 'COLOMode', 'active': 'bool', 'reason':
> 'COLOExitReason' } }
> > +
> > +##
> > +# @query-colo-status:
> > +#
> > +# Query COLO status while the vm is running.
> > +#
> > +# Returns: A @COLOStatus object showing the status.
> > +#
> > +# Example:
> > +#
> > +# -> { "execute": "query-colo-status" }
> > +# <- { "return": { "mode": "primary", "active": true, "reason":
> "request" } }
> > +#
> > +# Since: 3.0
> > +##
> > +{ 'command': 'query-colo-status',
> > +  'returns': 'COLOStatus' }
> > +
> >  ##
> >  # @migrate-recover:
> >  #
>

Re: [Qemu-devel] [PATCH V9 12/20] qapi: Add new command to query colo status

[Markus Armbruster]

Zhang Chen <zhangckid@gmail.com> writes:

> On Tue, Jul 3, 2018 at 7:09 PM, Markus Armbruster <armbru@redhat.com> wrote:
>
>> Zhang Chen <zhangckid@gmail.com> writes:
>>
>> > Libvirt or other high level software can use this command query colo
>> status.
>> > You can test this command like that:
>> > {'execute':'query-colo-status'}
>> >
>> > Signed-off-by: Zhang Chen <zhangckid@gmail.com>
[...]
>> > diff --git a/qapi/migration.json b/qapi/migration.json
>> > index c24f114104..73c64686ec 100644
>> > --- a/qapi/migration.json
>> > +++ b/qapi/migration.json
>> > @@ -1248,6 +1248,40 @@
>> >  ##
>> >  { 'command': 'xen-colo-do-checkpoint' }
>> >
>> > +##
>> > +# @COLOStatus:
>> > +#
>> > +# The result format for 'query-colo-status'.
>> > +#
>> > +# @mode: COLO running mode. If COLO is running, this field will return
>> > +#        'primary' or 'secondary'.
>>
>> Please mention that @mode is "none" when COLO is not running.
>>
>
> OK.
>
>
>>
>> > +#
>> > +# @active: true if COLO is active.
>>
>> Please use consistent terminology: pick one of "COLO is running", "COLO
>> is active" and stick to it.  v8 had that here, v9 regressed.  Also use
>> this wording for the comment improvement I requested for PATCH 11.
>>
>> However, isn't @active redundant with @mode?
>>
>>
> I re-think about this and review the codes.
> The 'none' mode can cover this field, I will remove the @active in next
> version.

I like it.

> By the way, can you review the diagram patch as your comments?
> (have some action not related to qmp, so I just drew a general diagram.)

I need to find some time for it.  Do not hold the series until I do.