Commit Graph

16 Commits

Author SHA1 Message Date
Li Zhijian 862ee1e07e colo-compare: fix missing compare_seq initialization
Fixes: f449c9e549 ("colo: compare the packet based on the tcp sequence
number")

Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: Zhang Chen <chen.zhang@intel.com>
Reviewed-by: Zhang Chen <chen.zhang@intel.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2020-11-11 16:52:23 +08:00
Lukas Straub 9c55fe9408 net/colo-compare.c: Fix deadlock in compare_chr_send
The chr_out chardev is connected to a filter-redirector
running in the main loop. qemu_chr_fe_write_all might block
here in compare_chr_send if the (socket-)buffer is full.
If another filter-redirector in the main loop want's to
send data to chr_pri_in it might also block if the buffer
is full. This leads to a deadlock because both event loops
get blocked.

Fix this by converting compare_chr_send to a coroutine and
putting the packets in a send queue.

Signed-off-by: Lukas Straub <lukasstraub2@web.de>
Reviewed-by: Zhang Chen <chen.zhang@intel.com>
Tested-by: Zhang Chen <chen.zhang@intel.com>
Signed-off-by: Zhang Chen <chen.zhang@intel.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2020-06-18 21:05:52 +08:00
Marc-André Lureau e05ae1d9fb net: do not depend on slirp internals
Only slirp/libslirp.h should be included.

Instead of using some slirp declarations and utility functions directly,
let's copy them in net/util.h.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
2019-01-14 00:44:29 +01:00
Zhang Chen 24525e93c1 filter-rewriter: handle checkpoint and failover event
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>
Signed-off-by: Zhang Chen <chen.zhang@intel.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2018-10-19 11:15:03 +08:00
Zhang Chen 6214231abd filter-rewriter: Add TCP state machine and fix memory leak in connection_track_table
We add almost full TCP state machine in filter-rewriter, except
TCPS_LISTEN and some simplify in VM active close FIN states.
The reason for this simplify job is because guest kernel will track
the TCP status and wait 2MSL time too, if client resend the FIN packet,
guest will resend the last ACK, so we needn't wait 2MSL time in filter-rewriter.

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

Let's 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>
Signed-off-by: Zhang Chen <chen.zhang@intel.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2018-10-19 11:15:03 +08:00
Michael S. Tsirkin f27f01db03 colo: use local path for local headers
When pulling in headers that are in the same directory as the C file (as
opposed to one in include/), we should use its relative path, without a
directory.

Reviewed-by: Zhang Chen <zhangckid@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2018-06-01 19:20:38 +03:00
Mao Zhongyi f449c9e549 colo: compare the packet based on the tcp sequence number
Packet size some time different or when network is busy.
Based on same payload size, but TCP protocol can not
guarantee send the same one packet in the same way,

like that:
We send this payload:
------------------------------
| header |1|2|3|4|5|6|7|8|9|0|
------------------------------

primary:
ppkt1:
----------------
| header |1|2|3|
----------------
ppkt2:
------------------------
| header |4|5|6|7|8|9|0|
------------------------

secondary:
spkt1:
------------------------------
| header |1|2|3|4|5|6|7|8|9|0|
------------------------------

In the original method, ppkt1 and ppkt2 are different in size and
spkt1, so they can't compare and trigger the checkpoint.

I have tested FTP get 200M and 1G file many times, I found that
the performance was less than 1% of the native.

Now I reconstructed the comparison of TCP packets based on the
TCP sequence number. first of all, ppkt1 and spkt1 have the same
starting sequence number, so they can compare, even though their
length is different. And then ppkt1 with a smaller payload length
is used as the comparison length, if the payload is same, send
out the ppkt1 and record the offset(the length of ppkt1 payload)
in spkt1. The next comparison, ppkt2 and spkt1 can be compared
from the recorded position of spkt1.

like that:
----------------
| header |1|2|3| ppkt1
---------|-----|
         |     |
---------v-----v--------------
| header |1|2|3|4|5|6|7|8|9|0| spkt1
---------------|\------------|
               | \offset     |
      ---------v-------------v
      | header |4|5|6|7|8|9|0| ppkt2
      ------------------------

In this way, the performance can reach native 20% in my multiple
tests.

Cc: Zhang Chen <zhangckid@gmail.com>
Cc: Li Zhijian <lizhijian@cn.fujitsu.com>
Cc: Jason Wang <jasowang@redhat.com>

Signed-off-by: Mao Zhongyi <maozy.fnst@cn.fujitsu.com>
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: Zhang Chen <zhangckid@gmail.com>
Reviewed-by: Zhang Chen <zhangckid@gmail.com>
Tested-by: Zhang Chen <zhangckid@gmail.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2018-01-29 16:05:37 +08:00
Mao Zhongyi 8fa5ad6dfb colo: Consolidate the duplicate code chunk into a routine
Consolidate the code that extract the ip address(src,dst) and
port number(src,dst) of the packet into a separate routine
extract_ip_and_port() since the same chunk of code is called
from two place.

Cc: Zhang Chen <zhangckid@gmail.com>
Cc: Li Zhijian <lizhijian@cn.fujitsu.com>
Cc: Jason Wang <jasowang@redhat.com>
Signed-off-by: Mao Zhongyi <maozy.fnst@cn.fujitsu.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2017-11-13 15:46:37 +08:00
Zhang Chen 5cc444d367 net/colo.c: Add vnet packet parse feature in colo-proxy
Make colo-compare and filter-rewriter can parse vnet packet.

Signed-off-by: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2017-07-17 20:13:51 +08:00
Zhang Chen ada1a33f9a net/colo.c: Make vnet_hdr_len as packet property
We can use this property flush and send packet with vnet_hdr_len.

Signed-off-by: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2017-07-17 20:13:48 +08:00
zhanghailiang 0e79668e1f net/colo: fix memory double free error
The 'primary_list' and 'secondary_list' members of struct Connection
is not allocated through dynamically g_queue_new(), but we free it by using
g_queue_free(), which will lead to a double-free bug.

Reviewed-by: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2017-03-06 11:46:02 +08:00
Zhang Chen 30656b097e filter-rewriter: rewrite tcp packet to keep secondary connection
We will rewrite tcp packet secondary received and sent.
When colo guest is a tcp server.

Firstly, client start a tcp handshake. the packet's seq=client_seq,
ack=0,flag=SYN. COLO primary guest get this pkt and mirror(filter-mirror)
to secondary guest, secondary get it use filter-redirector.
Then,primary guest response pkt
(seq=primary_seq,ack=client_seq+1,flag=ACK|SYN).
secondary guest response pkt
(seq=secondary_seq,ack=client_seq+1,flag=ACK|SYN).
In here,we use filter-rewriter save the secondary_seq to it's tcp connection.
Finally handshake,client send pkt
(seq=client_seq+1,ack=primary_seq+1,flag=ACK).
Here,filter-rewriter can get primary_seq, and rewrite ack from primary_seq+1
to secondary_seq+1, recalculate checksum. So the secondary tcp connection
kept good.

When we send/recv packet.
client send pkt(seq=client_seq+1+data_len,ack=primary_seq+1,flag=ACK|PSH).
filter-rewriter rewrite ack and send to secondary guest.

primary guest response pkt
(seq=primary_seq+1,ack=client_seq+1+data_len,flag=ACK)
secondary guest response pkt
(seq=secondary_seq+1,ack=client_seq+1+data_len,flag=ACK)
we rewrite secondary guest seq from secondary_seq+1 to primary_seq+1.
So tcp connection kept good.

In code We use offset( = secondary_seq - primary_seq )
to rewrite seq or ack.
handle_primary_tcp_pkt: tcp_pkt->th_ack += offset;
handle_secondary_tcp_pkt: tcp_pkt->th_seq -= offset;

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>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2016-09-27 17:54:22 +08:00
Zhang Chen afe4612409 filter-rewriter: track connection and parse packet
We use net/colo.h to track connection and parse packet

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>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2016-09-27 17:54:22 +08:00
Zhang Chen 0682e15b19 colo-compare: introduce packet comparison thread
If primary packet is same with secondary packet,
we will send primary packet and drop secondary
packet, otherwise notify COLO frame to do checkpoint.
If primary packet comes but secondary packet does not,
after REGULAR_PACKET_CHECK_MS milliseconds we set
the primary packet as old_packet,then do a checkpoint.

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>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2016-09-27 17:54:22 +08:00
Zhang Chen b6540d403d colo-compare: track connection and enqueue packet
In this patch we use kernel jhash table to track
connection, and then enqueue net packet like this:

+ 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  +
                  +--------+  +--------+    +--------+ +--------+

We use conn_list to record connection info.
When we want to enqueue a packet, firstly get the
connection from connection_track_table. then push
the packet to g_queue(pri/sec) in it's own conn.

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>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2016-09-27 17:54:21 +08:00
Zhang Chen 59509ec16b net/colo.c: add colo.c to define and handle packet
The net/colo.c is used by colo-compare and filter-rewriter.
this can share common data structure like net packet,
and other functions.

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>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2016-09-27 17:54:21 +08:00