0.存在的疑惑
- glusterd启动后怎么把glusterfsd的brick进程拉起来？
- glusterfsd启动的参数从哪里获取？
- glusterfsd如何加载的呢？
- glusterfsd和glusterd启动后各自都是什么角色？(后续再讨论)
1. glusterfs的入口函数解释
- glusterfsd中main方法加载xlator {name = 0x687dd0 "management", type = 0x687f50 "mgmt/glusterd"}，然后fork一个子进程加载mgmt/glusterd中的init方法
2.glusterd启动过程
- 子进程中调用mgmt/glusterd对应源文件中glusterd.c中的init,针对glusterd进行初始化，依次会调用如下方法:
- glusterfs_volumes_init
- glusterd.c:init
- glusterd_spawn_daemons
- glusterd_restart_bricks
- glusterd_brick_start
- glusterd_volume_start_glusterfs
- runner_run
- runner_start:fork子进程，调用execvp加载/usr/local/sbin/glusterfsd二进制文件
int runner_start(runner_t *runner) { //-----忽略---------------- execvp(runner->argv[0], runner->argv); //-----忽略---------------- }
3.glusterfsd如何加载xlator
-
glusterfsd是通过读取配置文件/var/lib/glusterd/vols/dht_vol/dht_vol.172.17.0.2.data-brick.vol来加载glusterfsd运行期间需要的xlator，这些配置信息是用户创建volume时候系统生成的
截屏2020-02-21下午8.03.09.png
4. glusterd启动后进程列表
-
runner_start后继续glusterfsd.c中的main方法，启动对应的服务，glusterfsd正式启动了，就如systemctl start glusterd后出现如下的结果:
image.png
5.glusterfsd启动流程
- 上个步骤通过runner_start加载glusterfsd的二进制进程，glusterfsd进入初始化节点，首先 glusterfs_listener_init 初始化tcp连接
- glusterfsd通过tcp连接到glusterd获取volume xlator信息，准备构建xlator的graph.
volume xlator信息如下:
(gdb) p rsp.spec
$6 = 0x7fffe4002fc0 "volume dht_vol-posix\n type storage/posix\n option shared-brick-count 1\n option volume-id 25305c2d-317f-45e9-8e60-be322ed69ee1\n option directory /data/brick\nend-volume\n\nvolume dht_vol-trash\n type features/trash\n option trash-internal-op off\n option brick-path /data/brick\n option trash-dir .trashcan\n subvolumes dht_vol-posix\nend-volume\n\nvolume dht_vol-changelog\n type features/changelog\n option changelog-barrier-timeout 120\n option changelog-dir /data/brick/.glusterfs/changelogs\n option changelog-brick /data/brick\n subvolumes dht_vol-trash\nend-volume\n\nvolume dht_vol-bitrot-stub\n type features/bitrot-stub\n option bitrot disable\n option export /data/brick\n subvolumes dht_vol-changelog\nend-volume\n\nvolume dht_vol-access-control\n type features/access-control\n subvolumes dht_vol-bitrot-stub\nend-volume\n\nvolume dht_vol-locks\n type features/locks\n option enforce-mandatory-lock off\n subvolumes dht_vol-access-control\nend-volume\n\nvolume dht_vol-worm\n type features/worm\n option worm-files-deletable on\n option worm-file-level off\n option worm off\n subvolumes dht_vol-locks\nend-volume\n\nvolume dht_vol-read-only\n type features/read-only\n option read-only off\n subvolumes dht_vol-worm\nend-volume\n\nvolume dht_vol-leases\n type features/leases\n option leases off\n subvolumes dht_vol-read-only\nend-volume\n\nvolume dht_vol-upcall\n type features/upcall\n option cache-invalidation off\n subvolumes dht_vol-leases\nend-volume\n\nvolume dht_vol-io-threads\n type performance/io-threads\n subvolumes dht_vol-upcall\nend-volume\n\nvolume dht_vol-selinux\n type features/selinux\n option selinux on\n subvolumes dht_vol-io-threads\nend-volume\n\nvolume dht_vol-marker\n type features/marker\n option inode-quota off\n option quota off\n option gsync-force-xtime off\n option xtime off\n option quota-version 0\n option timestamp-file /var/lib/glusterd/vols/dht_vol/marker.tstamp\n option volume-uuid 25305c2d-317f-45e9-8e60-be322ed69ee1\n subvolumes dht_vol-selinux\nend-volume\n\nvolume dht_vol-barrier\n type features/barrier\n option barrier-timeout 120\n option barrier disable\n subvolumes dht_vol-marker\nend-volume\n\nvolume dht_vol-index\n type features/index\n option xattrop-pending-watchlist trusted.afr.dht_vol-\n option xattrop-dirty-watchlist trusted.afr.dirty\n option index-base /data/brick/.glusterfs/indices\n subvolumes dht_vol-barrier\nend-volume\n\nvolume dht_vol-quota\n type features/quota\n option deem-statfs off\n option server-quota off\n option volume-uuid dht_vol\n subvolumes dht_vol-index\nend-volume\n\nvolume dht_vol-io-stats\n type debug/io-stats\n option count-fop-hits off\n option latency-measurement off\n option log-level INFO\n option unique-id /data/brick\n subvolumes dht_vol-quota\nend-volume\n\nvolume /data/brick\n type performance/decompounder\n subvolumes dht_vol-io-stats\nend-volume\n\nvolume dht_vol-server\n type protocol/server\n option transport.listen-backlog 1024\n option transport.socket.keepalive-count 9\n option transport.socket.keepalive-interval 2\n option transport.socket.keepalive-time 20\n option transport.socket.ssl-enabled off\n option transport.socket.keepalive 1\n option auth.addr./data/brick.allow *\n option auth-path /data/brick\n option auth.login.b26ac1fd-40a4-4c6e-b211-a9f2b58beedc.password 4eda9afe-9466-4283-b175-6020d5981994\n option auth.login./data/brick.allow b26ac1fd-40a4-4c6e-b211-a9f2b58beedc\n option transport.address-family inet\n option transport-type tcp\n subvolumes /data/brick\nend-volume\n"
- 根据xlator获取初构建graph信息，初始化每个xlator的init方法，这个时候glusterfsd初始化成功
6. gdb 调试方法
- gdb break 信息
set print pretty on
//调试子进程,子进程会加载执行mgmt/glusterd/src/glusterd.c:init
set follow-fork-mode child
set detach-on-fork off
br glusterfsd.c:main
br br glusterfs_volumes_init //glusterd和glusterfsd都会调用该方法
br glusterd.c:init
//------ 进入init函数后执行如下------
/* 进入这个函数后设置调试父进程
set follow-fork-mode parent
set detach-on-fork on
*/
br glusterd_spawn_daemons
br glusterd_restart_bricks
br glusterd_brick_start
br glusterd_volume_start_glusterfs
/* 进入这个函数后设置调试父进程
set follow-fork-mode child
set detach-on-fork on
*/
br runner_run
br runner_log
br runner_start
/** 进入runner_start 后设置如下断点，glusterfsd启动以后会按照如下的调用链进行 */
br glusterfs_volumes_init
br glusterfs_listener_init //glusterd不会调用该方法
br glusterfs_mgmt_init //glusterd不会调用该方法
br mgmt_rpc_notify
br glusterfs_volfile_fetch
br glusterfs_volfile_fetch_one
br mgmt_getspec_cbk
br glusterfs_process_volfp
br glusterfs_graph_activate
br glusterfs_graph_init
- 1.glusterd gdb日志
[root@b94a78ebfc80 ~]$ gdb glusterd
GNU gdb (GDB) Red Hat Enterprise Linux 7.6.1-115.el7
Copyright (C) 2013 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-redhat-linux-gnu".
For bug reporting instructions, please see:
breakpoint already hit 1 time
1.1 y 0x000000000040b71d in main at glusterfsd.c:2746 inf 1
1.2 y 0x000000000040b71d in main at glusterfsd.c:2746 inf 2
2 breakpoint keep y 0x00007ffff1f3a7ee in init at glusterd.c:1373 inf 2
breakpoint already hit 1 time
3 breakpoint keep y 0x00007ffff1f79f85 in glusterd_spawn_daemons at glusterd-utils.c:3619 inf 2
breakpoint already hit 1 time
4 breakpoint keep y 0x00007ffff1f832e3 in glusterd_restart_bricks at glusterd-utils.c:6334 inf 2
breakpoint already hit 1 time
5 breakpoint keep y 0x00007ffff1f826cd in glusterd_brick_start at glusterd-utils.c:6107 inf 2
6 breakpoint keep y 0x00007ffff1f73f5f in glusterd_volume_start_glusterfs at glusterd-utils.c:2024 inf 2
7 breakpoint keep y
7.1 y 0x00007ffff7b35f04 in runner_run at run.c:430 inf 1
7.2 y 0x00007ffff7b35f04 in runner_run at run.c:430 inf 2
8 breakpoint keep y
8.1 y 0x00007ffff7b35825 in runner_start at run.c:259 inf 1
8.2 y 0x00007ffff7b35825 in runner_start at run.c:259 inf 2
(gdb) c
Continuing.
Breakpoint 5, glusterd_brick_start (volinfo=0x6db4b0, brickinfo=0x6ef490, wait=false, only_connect=false) at glusterd-utils.c:6107
6107 int ret = -1;
(gdb) c
Continuing.
[New Thread 0x7fffeee05700 (LWP 991)]
Breakpoint 6, glusterd_volume_start_glusterfs (volinfo=0x6db4b0, brickinfo=0x6ef490, wait=false) at glusterd-utils.c:2024
2024 int32_t ret = -1;
(gdb) c
Continuing.
[New process 992]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
[Switching to Thread 0x7ffff342d700 (LWP 992)]
Breakpoint 8, runner_start (runner=0x7fffef800e00) at run.c:259
259 int pi[3][2] = {{-1, -1}, {-1, -1}, {-1, -1}};
(gdb) n
261 int ret = 0;
(gdb)
262 int errno_priv = 0;
(gdb)
263 int i = 0;
(gdb)
266 if (runner->runerr || !runner->argv) {
(gdb)
271 GF_ASSERT(runner->argv[0]);
(gdb) set follow-fork-mode child
(gdb) set detach-on-fork on
(gdb) n
276 ret = pipe(xpi);
(gdb)
277 if (ret != -1)
(gdb)
278 ret = fcntl(xpi[1], F_SETFD, FD_CLOEXEC);
(gdb)
280 for (i = 0; i < 3; i++) {
(gdb)
281 if (runner->chfd[i] != -2)
(gdb)
282 continue;
(gdb)
280 for (i = 0; i < 3; i++) {
(gdb)
281 if (runner->chfd[i] != -2)
(gdb)
282 continue;
(gdb)
280 for (i = 0; i < 3; i++) {
(gdb)
281 if (runner->chfd[i] != -2)
(gdb)
282 continue;
(gdb)
280 for (i = 0; i < 3; i++) {
(gdb)
291 if (ret != -1)
(gdb)
292 runner->chpid = fork();
(gdb)
[New process 995]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
[Switching to Thread 0x7ffff342d700 (LWP 995)]
293 switch (runner->chpid) {
327 if (ret != -1) {
(gdb)
328 int fdv[4] = {0, 1, 2, xpi[1]};
(gdb)
330 ret = close_fds_except(fdv, sizeof(fdv) / sizeof(*fdv));
(gdb)
333 if (ret != -1) {
(gdb)
335 sigemptyset(&set);
(gdb)
336 sigprocmask(SIG_SETMASK, &set, NULL);
(gdb)
338 execvp(runner->argv[0], runner->argv);
(gdb) p runner->argv[0]
$1 = 0x7fffe8000c60 "/usr/local/sbin/glusterfsd"
(gdb) p runner->argv
$2 = (char **) 0x7fffe8000970
(gdb) p/s runner->argv
$3 = (char **) 0x7fffe8000970
(gdb) p/s runner->argv[1]
$4 = 0x7fffe8000ce0 "-s"
(gdb) p/s runner->argv[2]
$5 = 0x7fffe8000d50 "172.17.0.2"
(gdb) p/s runner->argv[3]
$6 = 0x7fffe8000dc0 "--volfile-id"
(gdb) p/s runner->argv[4]
$7 = 0x7fffe8000e30 "dht_vol.172.17.0.2.data-brick"
(gdb) p/s runner->argv[5]
$8 = 0x7fffe8000eb0 "-p"
(gdb) p/s runner->argv[6]
$9 = 0x7fffe8000f20 "/var/run/gluster/vols/dht_vol/172.17.0.2-data-brick.pid"
(gdb) p/s runner->argv[7]
$10 = 0x7fffe8000fc0 "-S"
(gdb) p/s runner->argv[8]
$11 = 0x7fffe8001030 "/var/run/gluster/cb954c564295c3be.socket"
(gdb) p/s runner->argv[9]
$12 = 0x7fffe80010c0 "--brick-name"
(gdb) p/s runner->argv[10]
$13 = 0x7fffe8001130 "/data/brick"
(gdb) p/s runner->argv[11]
$14 = 0x7fffe80011a0 "-l"
(gdb) p/s runner->argv[12]
$15 = 0x7fffe8001210 "/var/log/glusterfs/bricks/data-brick.log"
(gdb) p/s runner->argv[13]
$16 = 0x7fffe80012a0 "--xlator-option"
(gdb) p/s runner->argv[14]
$17 = 0x7fffe8001310 "*-posix.glusterd-uuid=88efffbe-ce9e-4117-8d1a-77de0a8ecd75"
(gdb) p/s runner->argv[15]
$18 = 0x7fffe80013b0 "--process-name"
(gdb) p/s runner->argv[16]
$19 = 0x7fffe8001420 "brick"
(gdb) p/s runner->argv[17]
$20 = 0x7fffe8001490 "--brick-port"
(gdb) p/s runner->argv[18]
$21 = 0x7fffe8001500 "49152"
(gdb) p/s runner->argv[19]
$22 = 0x7fffe8001570 "--xlator-option"
(gdb) p/s runner->argv[20]
$23 = 0x7fffe80015e0 "dht_vol-server.listen-port=49152"
(gdb) p/s runner->argv[21]
$24 = 0x0
(gdb)
- glusterfsd gdb 日志
(gdb) info break
Num Type Disp Enb Address What
1 breakpoint keep y
breakpoint already hit 2 times
1.1 y 0x000000000040b71d in main at glusterfsd.c:2746 inf 1
1.2 y 0x000000000040b71d in main at glusterfsd.c:2746 inf 5, 4, 3
2 breakpoint keep y glusterd.c:init inf 5, 4, 3
breakpoint already hit 1 time
3 breakpoint keep y glusterd_spawn_daemons inf 5, 4, 3
breakpoint already hit 1 time
4 breakpoint keep y glusterd_restart_bricks inf 5, 4, 3
breakpoint already hit 1 time
5 breakpoint keep y glusterd_brick_start inf 5, 4, 3
breakpoint already hit 1 time
6 breakpoint keep y glusterd_volume_start_glusterfs inf 5, 4, 3
breakpoint already hit 1 time
7 breakpoint keep y
7.1 y 0x00007ffff7b35f04 in runner_run at run.c:430 inf 1
7.2 y 0x00007ffff7b35f04 in runner_run at run.c:430 inf 5, 4, 3
8 breakpoint keep y
breakpoint already hit 1 time
8.1 y 0x00007ffff7b35825 in runner_start at run.c:259 inf 1
8.2 y 0x00007ffff7b35825 in runner_start at run.c:259 inf 5, 4, 3
9 breakpoint keep y server-rpc-fops_v2.c:server4_0_mkdir
10 breakpoint keep y server-resolve.c:server_resolve
11 breakpoint keep y
breakpoint already hit 1 time
11.1 y 0x000000000040b603 in glusterfs_volumes_init at glusterfsd.c:2704 inf 1
11.2 y 0x000000000040b603 in glusterfs_volumes_init at glusterfsd.c:2704 inf 5, 4, 3
12 breakpoint keep y
12.1 y 0x000000000040b390 in glusterfs_process_volfp at glusterfsd.c:2626 inf 1
12.2 y 0x000000000040b390 in glusterfs_process_volfp at glusterfsd.c:2626 inf 5, 4, 3
13 breakpoint keep y
13.1 y 0x000000000040710f in get_volfp at glusterfsd.c:781 inf 1
13.2 y 0x000000000040710f in get_volfp at glusterfsd.c:781 inf 5, 4, 3
14 breakpoint keep y
breakpoint already hit 1 time
14.1 y 0x0000000000412581 in glusterfs_mgmt_init at glusterfsd-mgmt.c:2648 inf 1
14.2 y 0x0000000000412581 in glusterfs_mgmt_init at glusterfsd-mgmt.c:2648 inf 5, 4, 3
15 breakpoint keep y
breakpoint already hit 1 time
---Type to continue, or q to quit---
15.1 y 0x0000000000411848 in glusterfs_volfile_fetch at glusterfsd-mgmt.c:2270 inf 1
15.2 y 0x0000000000411848 in glusterfs_volfile_fetch at glusterfsd-mgmt.c:2270 inf 5, 4, 3
16 breakpoint keep y
breakpoint already hit 1 time
16.1 y 0x00000000004114ed in glusterfs_volfile_fetch_one at glusterfsd-mgmt.c:2166 inf 1
16.2 y 0x00000000004114ed in glusterfs_volfile_fetch_one at glusterfsd-mgmt.c:2166 inf 5, 4, 3
17 breakpoint keep y
breakpoint already hit 1 time
17.1 y 0x0000000000410a85 in mgmt_getspec_cbk at glusterfsd-mgmt.c:1922 inf 1
17.2 y 0x0000000000410a85 in mgmt_getspec_cbk at glusterfsd-mgmt.c:1922 inf 5, 4, 3
18 breakpoint keep y
18.1 y 0x000000000040b390 in glusterfs_process_volfp at glusterfsd.c:2626 inf 1
18.2 y 0x000000000040b390 in glusterfs_process_volfp at glusterfsd.c:2626 inf 5, 4, 3
(gdb)