Re: [Qemu-devel] [RFC PATCH V10 2/7] colo-base: add colo-base to define and handle packet

[Jason Wang <jasowang@redhat.com>]

On 2016年07月26日 09:49, Zhang Chen wrote:
> COLO-base used by colo-compare and filter-rewriter.

s/used/is used/

> this can share common data structure like:net packet,

s/this/This/ and ':' looks unnecessary.
> and share other functions.

s/share//

>
> Signed-off-by: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
> Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
> ---
>   net/Makefile.objs  |   1 +
>   net/colo-base.c    |  74 +++++++++++++++++++++++++++++++++
>   net/colo-base.h    |  38 +++++++++++++++++
>   net/colo-compare.c | 119 ++++++++++++++++++++++++++++++++++++++++++++++++++++-
>   trace-events       |   3 ++
>   5 files changed, 233 insertions(+), 2 deletions(-)
>   create mode 100644 net/colo-base.c
>   create mode 100644 net/colo-base.h
>
> diff --git a/net/Makefile.objs b/net/Makefile.objs
> index ba92f73..119589f 100644
> --- a/net/Makefile.objs
> +++ b/net/Makefile.objs
> @@ -17,3 +17,4 @@ common-obj-y += filter.o
>   common-obj-y += filter-buffer.o
>   common-obj-y += filter-mirror.o
>   common-obj-y += colo-compare.o
> +common-obj-y += colo-base.o
> diff --git a/net/colo-base.c b/net/colo-base.c
> new file mode 100644
> index 0000000..f5d5de9
> --- /dev/null
> +++ b/net/colo-base.c

I was thinking maybe just use colo.c is better here.

> @@ -0,0 +1,74 @@
> +/*
> + * COarse-grain LOck-stepping Virtual Machines for Non-stop Service (COLO)
> + * (a.k.a. Fault Tolerance or Continuous Replication)
> + *
> + * Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD.
> + * Copyright (c) 2016 FUJITSU LIMITED
> + * Copyright (c) 2016 Intel Corporation
> + *
> + * Author: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or
> + * later.  See the COPYING file in the top-level directory.
> + */
> +
> +#include "qemu/osdep.h"
> +#include "qemu/error-report.h"
> +#include "net/colo-base.h"
> +
> +int parse_packet_early(Packet *pkt)
> +{
> +    int network_length;
> +    uint8_t *data = pkt->data;
> +    uint16_t l3_proto;
> +    ssize_t l2hdr_len = eth_get_l2_hdr_length(data);
> +
> +    if (pkt->size < ETH_HLEN) {
> +        error_report("pkt->size < ETH_HLEN");
> +        return 1;
> +    }
> +    pkt->network_layer = data + ETH_HLEN;
> +    l3_proto = eth_get_l3_proto(data, l2hdr_len);
> +    if (l3_proto != ETH_P_IP) {
> +        return 1;
> +    }
> +
> +    network_length = pkt->ip->ip_hl * 4;
> +    if (pkt->size < ETH_HLEN + network_length) {
> +        error_report("pkt->size < network_layer + network_length");
> +        return 1;
> +    }
> +    pkt->transport_layer = pkt->network_layer + network_length;
> +    if (!pkt->transport_layer) {

Looks like at least pkt->network_layer can't be zero, so I wonder how 
this condition were met.

> +        error_report("pkt->transport_layer is valid");
> +        return 1;
> +    }
> +
> +    return 0;
> +}
> +
> +Packet *packet_new(const void *data, int size)
> +{
> +    Packet *pkt = g_slice_new(Packet);
> +
> +    pkt->data = g_memdup(data, size);
> +    pkt->size = size;
> +
> +    return pkt;
> +}
> +
> +void packet_destroy(void *opaque, void *user_data)

What's the reason of using void * instead of Packet * directly? And 
user_data were not used in this function.

> +{
> +    Packet *pkt = opaque;
> +
> +    g_free(pkt->data);
> +    g_slice_free(Packet, pkt);
> +}
> +
> +/*
> + * Clear hashtable, stop this hash growing really huge
> + */
> +void connection_hashtable_reset(GHashTable *connection_track_table)
> +{
> +    g_hash_table_remove_all(connection_track_table);
> +}
> diff --git a/net/colo-base.h b/net/colo-base.h
> new file mode 100644
> index 0000000..48835e7
> --- /dev/null
> +++ b/net/colo-base.h
> @@ -0,0 +1,38 @@
> +/*
> + * COarse-grain LOck-stepping Virtual Machines for Non-stop Service (COLO)
> + * (a.k.a. Fault Tolerance or Continuous Replication)
> + *
> + * Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD.
> + * Copyright (c) 2016 FUJITSU LIMITED
> + * Copyright (c) 2016 Intel Corporation
> + *
> + * Author: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or
> + * later.  See the COPYING file in the top-level directory.
> + */
> +
> +#ifndef QEMU_COLO_BASE_H
> +#define QEMU_COLO_BASE_H
> +
> +#include "slirp/slirp.h"
> +#include "qemu/jhash.h"
> +
> +#define HASHTABLE_MAX_SIZE 16384
> +
> +typedef struct Packet {
> +    void *data;
> +    union {
> +        uint8_t *network_layer;

I think it would be better to use "network_header" here.

> +        struct ip *ip;
> +    };
> +    uint8_t *transport_layer;

And "transport_header" here.

And why not union tcp header here? I'm asking since ip header were 
unioned above.

> +    int size;
> +} Packet;
> +
> +int parse_packet_early(Packet *pkt);
> +void connection_hashtable_reset(GHashTable *connection_track_table);
> +Packet *packet_new(const void *data, int size);
> +void packet_destroy(void *opaque, void *user_data);
> +
> +#endif /* QEMU_COLO_BASE_H */
> diff --git a/net/colo-compare.c b/net/colo-compare.c
> index 0402958..7c52cc8 100644
> --- a/net/colo-compare.c
> +++ b/net/colo-compare.c
> @@ -27,13 +27,38 @@
>   #include "sysemu/char.h"
>   #include "qemu/sockets.h"
>   #include "qapi-visit.h"
> +#include "net/colo-base.h"
> +#include "trace.h"
>   
>   #define TYPE_COLO_COMPARE "colo-compare"
>   #define COLO_COMPARE(obj) \
>       OBJECT_CHECK(CompareState, (obj), TYPE_COLO_COMPARE)
>   
>   #define COMPARE_READ_LEN_MAX NET_BUFSIZE
> +#define MAX_QUEUE_SIZE 1024
>   
> +/*
> +  + CompareState ++
> +  |               |
> +  +---------------+   +---------------+         +---------------+
> +  |conn list      +--->conn           +--------->conn           |
> +  +---------------+   +---------------+         +---------------+
> +  |               |     |           |             |          |
> +  +---------------+ +---v----+  +---v----+    +---v----+ +---v----+
> +                    |primary |  |secondary    |primary | |secondary
> +                    |packet  |  |packet  +    |packet  | |packet  +
> +                    +--------+  +--------+    +--------+ +--------+
> +                        |           |             |          |
> +                    +---v----+  +---v----+    +---v----+ +---v----+
> +                    |primary |  |secondary    |primary | |secondary
> +                    |packet  |  |packet  +    |packet  | |packet  +
> +                    +--------+  +--------+    +--------+ +--------+
> +                        |           |             |          |
> +                    +---v----+  +---v----+    +---v----+ +---v----+
> +                    |primary |  |secondary    |primary | |secondary
> +                    |packet  |  |packet  +    |packet  | |packet  +
> +                    +--------+  +--------+    +--------+ +--------+
> +*/
>   typedef struct CompareState {
>       Object parent;
>   
> @@ -46,12 +71,89 @@ typedef struct CompareState {
>       QTAILQ_ENTRY(CompareState) next;
>       SocketReadState pri_rs;
>       SocketReadState sec_rs;
> +
> +    /* hashtable to save connection */
> +    GHashTable *connection_track_table;
> +    /* to save unprocessed_connections */
> +    GQueue unprocessed_connections;
> +    /* proxy current hash size */
> +    uint32_t hashtable_size;
>   } CompareState;
>   
>   typedef struct CompareClass {
>       ObjectClass parent_class;
>   } CompareClass;
>   
> +enum {
> +    PRIMARY_IN = 0,
> +    SECONDARY_IN,
> +};
> +
> +static int compare_chr_send(CharDriverState *out,
> +                            const uint8_t *buf,
> +                            uint32_t size);
> +
> +/*
> + * Return 0 on success, if return -1 means the pkt
> + * is unsupported(arp and ipv6) and will be sent later
> + */
> +static int packet_enqueue(CompareState *s, int mode)
> +{
> +    Packet *pkt = NULL;
> +
> +    if (mode == PRIMARY_IN) {
> +        pkt = packet_new(s->pri_rs.buf, s->pri_rs.packet_len);
> +    } else {
> +        pkt = packet_new(s->sec_rs.buf, s->sec_rs.packet_len);
> +    }
> +
> +    if (parse_packet_early(pkt)) {
> +        packet_destroy(pkt, NULL);
> +        pkt = NULL;
> +        return -1;
> +    }
> +    /* TODO: get connection key from pkt */
> +
> +    /*
> +     * TODO: use connection key get conn from
> +     * connection_track_table
> +     */
> +
> +    /*
> +     * TODO: insert pkt to it's conn->primary_list
> +     * or conn->secondary_list
> +     */
> +
> +    return 0;
> +}
> +
> +static int compare_chr_send(CharDriverState *out,
> +                            const uint8_t *buf,
> +                            uint32_t size)
> +{
> +    int ret = 0;
> +    uint32_t len = htonl(size);
> +
> +    if (!size) {
> +        return 0;
> +    }
> +
> +    ret = qemu_chr_fe_write_all(out, (uint8_t *)&len, sizeof(len));
> +    if (ret != sizeof(len)) {
> +        goto err;
> +    }
> +
> +    ret = qemu_chr_fe_write_all(out, (uint8_t *)buf, size);
> +    if (ret != size) {
> +        goto err;
> +    }
> +
> +    return 0;
> +
> +err:
> +    return ret < 0 ? ret : -EIO;
> +}
> +
>   static char *compare_get_pri_indev(Object *obj, Error **errp)
>   {
>       CompareState *s = COLO_COMPARE(obj);
> @@ -99,12 +201,21 @@ static void compare_set_outdev(Object *obj, const char *value, Error **errp)
>   
>   static void compare_pri_rs_finalize(SocketReadState *pri_rs)
>   {
> -    /* if packet_enqueue pri pkt failed we will send unsupported packet */
> +    CompareState *s = container_of(pri_rs, CompareState, pri_rs);
> +
> +    if (packet_enqueue(s, PRIMARY_IN)) {
> +        trace_colo_compare_main("primary: unsupported packet in");
> +        compare_chr_send(s->chr_out, pri_rs->buf, pri_rs->packet_len);
> +    }
>   }
>   
>   static void compare_sec_rs_finalize(SocketReadState *sec_rs)
>   {
> -    /* if packet_enqueue sec pkt failed we will notify trace */
> +    CompareState *s = container_of(sec_rs, CompareState, sec_rs);
> +
> +    if (packet_enqueue(s, SECONDARY_IN)) {
> +        trace_colo_compare_main("secondary: unsupported packet in");
> +    }
>   }
>   
>   /*
> @@ -156,6 +267,10 @@ static void colo_compare_complete(UserCreatable *uc, Error **errp)
>       net_socket_rs_init(&s->pri_rs, compare_pri_rs_finalize);
>       net_socket_rs_init(&s->sec_rs, compare_sec_rs_finalize);
>   
> +    s->hashtable_size = 0;
> +
> +    /* use g_hash_table_new_full() to new a hashtable */
> +
>       return;
>   }
>   
> diff --git a/trace-events b/trace-events
> index ca7211b..703de1a 100644
> --- a/trace-events
> +++ b/trace-events
> @@ -1916,3 +1916,6 @@ aspeed_vic_update_fiq(int flags) "Raising FIQ: %d"
>   aspeed_vic_update_irq(int flags) "Raising IRQ: %d"
>   aspeed_vic_read(uint64_t offset, unsigned size, uint32_t value) "From 0x%" PRIx64 " of size %u: 0x%" PRIx32
>   aspeed_vic_write(uint64_t offset, unsigned size, uint32_t data) "To 0x%" PRIx64 " of size %u: 0x%" PRIx32
> +
> +# net/colo-compare.c
> +colo_compare_main(const char *chr) ": %s"