[CRIU] [PATCH 1/3] service: allow to execute page-server as a child process
Andrei Vagin
avagin at openvz.org
Tue May 16 22:07:11 PDT 2017
From: Andrei Vagin <avagin at virtuozzo.com>
In this case we can wait it and get an exit code.
For example, it will be useful for p.haul where one connection
is used several times, so we need a way how to understand that
page-server exited unexpectedly.
Signed-off-by: Andrei Vagin <avagin at virtuozzo.com>
---
criu/cr-service.c | 79 ++++++++++++++++++++++++++++++++++--------------
criu/include/page-xfer.h | 5 +++
criu/page-xfer.c | 13 ++++++++
images/rpc.proto | 8 +++++
4 files changed, 82 insertions(+), 23 deletions(-)
diff --git a/criu/cr-service.c b/criu/cr-service.c
index 8cf76dd..18ba2fd 100644
--- a/criu/cr-service.c
+++ b/criu/cr-service.c
@@ -705,12 +705,7 @@ static int pre_dump_loop(int sk, CriuReq *msg)
return dump_using_req(sk, msg->opts);
}
-struct ps_info {
- int pid;
- unsigned short port;
-};
-
-static int start_page_server_req(int sk, CriuOpts *req)
+static int start_page_server_req(int sk, CriuOpts *req, bool daemon_mode)
{
int ret = -1, pid, start_pipe[2];
ssize_t count;
@@ -735,35 +730,40 @@ static int start_page_server_req(int sk, CriuOpts *req)
pr_debug("Starting page server\n");
- pid = cr_page_server(true, false, start_pipe[1]);
+ pid = cr_page_server(daemon_mode, false, start_pipe[1]);
if (pid < 0)
goto out_ch;
- info.pid = pid;
- info.port = opts.port;
+ if (daemon_mode) {
+ info.pid = pid;
+ info.port = opts.port;
- count = write(start_pipe[1], &info, sizeof(info));
- if (count != sizeof(info))
- goto out_ch;
+ count = write(start_pipe[1], &info, sizeof(info));
+ if (count != sizeof(info))
+ goto out_ch;
+ }
ret = 0;
out_ch:
- if (ret < 0 && pid > 0)
+ if (daemon_mode && ret < 0 && pid > 0)
kill(pid, SIGKILL);
close(start_pipe[1]);
exit(ret);
}
close(start_pipe[1]);
- wait(&ret);
- if (WIFEXITED(ret)) {
- if (WEXITSTATUS(ret)) {
- pr_err("Child exited with an error\n");
+
+ if (daemon_mode) {
+ wait(&ret);
+ if (WIFEXITED(ret)) {
+ if (WEXITSTATUS(ret)) {
+ pr_err("Child exited with an error\n");
+ goto out;
+ }
+ } else {
+ pr_err("Child wasn't terminated normally\n");
goto out;
}
- } else {
- pr_err("Child wasn't terminated normally\n");
- goto out;
}
count = read(start_pipe[0], &info, sizeof(info));
@@ -771,11 +771,12 @@ out_ch:
if (count != sizeof(info))
goto out;
- success = true;
- ps.has_pid = true;
ps.pid = info.pid;
ps.has_port = true;
ps.port = info.port;
+
+ success = true;
+ ps.has_pid = true;
resp.ps = &ps;
pr_debug("Page server started\n");
@@ -802,6 +803,9 @@ static int chk_keepopen_req(CriuReq *msg)
if (msg->type == CRIU_REQ_TYPE__PAGE_SERVER)
/* This just fork()-s so no leaks */
return 0;
+ if (msg->type == CRIU_REQ_TYPE__PAGE_SERVER_CHLD)
+ /* This just fork()-s so no leaks */
+ return 0;
else if (msg->type == CRIU_REQ_TYPE__CPUINFO_DUMP ||
msg->type == CRIU_REQ_TYPE__CPUINFO_CHECK)
return 0;
@@ -946,6 +950,29 @@ out:
return send_criu_msg(sk, &resp);
}
+static int handle_wait_pid(int sk, int pid)
+{
+ CriuResp resp = CRIU_RESP__INIT;
+ bool success = false;
+ int status;
+
+ if (waitpid(pid, &status, 0) == -1) {
+ resp.cr_errno = errno;
+ pr_perror("Unable to wait %d", pid);
+ goto out;
+ }
+
+ resp.status = status;
+ resp.has_status = true;
+
+ success = true;
+out:
+ resp.type = CRIU_REQ_TYPE__WAIT_PID;
+ resp.success = success;
+
+ return send_criu_msg(sk, &resp);
+}
+
static int handle_cpuinfo(int sk, CriuReq *msg)
{
CriuResp resp = CRIU_RESP__INIT;
@@ -1031,7 +1058,13 @@ more:
ret = pre_dump_loop(sk, msg);
break;
case CRIU_REQ_TYPE__PAGE_SERVER:
- ret = start_page_server_req(sk, msg->opts);
+ ret = start_page_server_req(sk, msg->opts, true);
+ break;
+ case CRIU_REQ_TYPE__PAGE_SERVER_CHLD:
+ ret = start_page_server_req(sk, msg->opts, false);
+ break;
+ case CRIU_REQ_TYPE__WAIT_PID:
+ ret = handle_wait_pid(sk, msg->pid);
break;
case CRIU_REQ_TYPE__CPUINFO_DUMP:
case CRIU_REQ_TYPE__CPUINFO_CHECK:
diff --git a/criu/include/page-xfer.h b/criu/include/page-xfer.h
index 1f59bdb..0b92ec9 100644
--- a/criu/include/page-xfer.h
+++ b/criu/include/page-xfer.h
@@ -2,6 +2,11 @@
#define __CR_PAGE_XFER__H__
#include "pagemap.h"
+struct ps_info {
+ int pid;
+ unsigned short port;
+};
+
extern int cr_page_server(bool daemon_mode, bool lazy_dump, int cfd);
/*
diff --git a/criu/page-xfer.c b/criu/page-xfer.c
index fa3aacc..418bdc4 100644
--- a/criu/page-xfer.c
+++ b/criu/page-xfer.c
@@ -961,6 +961,19 @@ int cr_page_server(bool daemon_mode, bool lazy_dump, int cfd)
if (sk == -1)
return -1;
no_server:
+
+ if (!daemon_mode) {
+ struct ps_info info = {.pid = getpid(), .port = opts.port};
+ int count;
+
+ count = write(cfd, &info, sizeof(info));
+ close_safe(&cfd);
+ if (count != sizeof(info)) {
+ pr_perror("Unable to write ps_info");
+ exit(1);
+ }
+ }
+
ret = run_tcp_server(daemon_mode, &ask, cfd, sk);
if (ret != 0)
return ret > 0 ? 0 : -1;
diff --git a/images/rpc.proto b/images/rpc.proto
index 48e42e2..71f47d5 100644
--- a/images/rpc.proto
+++ b/images/rpc.proto
@@ -142,6 +142,9 @@ enum criu_req_type {
FEATURE_CHECK = 9;
VERSION = 10;
+
+ WAIT_PID = 11;
+ PAGE_SERVER_CHLD = 12;
}
/*
@@ -176,6 +179,9 @@ message criu_req {
* via RPC.
*/
optional criu_features features = 5;
+
+ /* 'pid' is used for WAIT_PID */
+ optional uint32 pid = 6;
}
/*
@@ -196,6 +202,8 @@ message criu_resp {
optional criu_features features = 8;
optional string cr_errmsg = 9;
optional criu_version version = 10;
+
+ optional int32 status = 11;
}
/* Answer for criu_req_type.VERSION requests */
--
2.9.3
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