zdtm: check pre-dump of shared memory

[root@fc24 criu]# python test/zdtm.py run -t zdtm/transition/shmem  --pre 3
=== Run 1/1 ================

======================== Run zdtm/transition/shmem in h ========================
cc -g -O2 -Wall -Werror -fno-strict-aliasing  -iquote ../lib/arch/x86/include -I../lib   shmem.c ../lib/libzdtmtst.a ../lib/libzdtmtst.a -o shmem
Start test
./shmem --pidfile=shmem.pid --outfile=shmem.out
Run criu pre-dump
Run criu pre-dump
Run criu pre-dump
Run criu dump
Run criu restore
Send the 15 signal to  33
Wait for zdtm/transition/shmem(33) to die for 0.100000
Test output: ================================
15:12:25.444:    33: FAIL: shmem.c:70: checksum mismatch: ea71000 109c9000

Cc: Eugene Batalov <eabatalov89@gmail.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

test/zdtm/transition/Makefile

@@ -23,6 +23,7 @@ TST_NOFILE	=	\
 		file_aio        \
 		socket-tcp      \
 		socket-tcp6     \
+		shmem		\
 
 
 TST_FILE	=	\

test/zdtm/transition/shmem.c

+#define _GNU_SOURCE
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <signal.h>
+#include <sys/wait.h>
+
+#include "zdtmtst.h"
+
+const char *test_author	= "Andrei Vagin <avagin@virtuozzo.com>";
+
+#define MEM_SIZE (1<<25)
+
+int main(int argc, char **argv)
+{
+	pid_t pid;
+	void *addr;
+	int *sum, status;
+	long size;
+
+	test_init(argc, argv);
+
+	sum = mmap(NULL, PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_SHARED, -1, 0);
+	if (sum == MAP_FAILED)
+		return 1;
+	addr = mmap(NULL, MEM_SIZE, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_SHARED, -1, 0);
+	if (addr == MAP_FAILED)
+		return 1;
+
+	pid = fork();
+	if (pid < 0)
+		return 1;
+
+	if (pid == 0) {
+		int i = 0;
+		long size = PAGE_SIZE, old_size = MEM_SIZE;
+
+		status = 0;
+		while (test_go()) {
+			addr = mremap(addr, old_size, size, MREMAP_MAYMOVE);
+
+			status -= *((int *)(addr + size - PAGE_SIZE));
+
+			*((int *)(addr + size - PAGE_SIZE)) = i++;
+
+			status += *((int *)(addr + size - PAGE_SIZE));
+
+			old_size = size;
+			size += PAGE_SIZE;
+			if (size > MEM_SIZE)
+				size = PAGE_SIZE;
+		}
+		*sum = status;
+		return 0;
+	}
+
+	test_daemon();
+	test_waitsig();
+
+	kill(pid, SIGTERM);
+	status = -1;
+	waitpid(pid, &status, 0);
+	if (status) {
+		pr_perror("The child return non-zero code: %d\n", status);
+		return 1;
+	}
+
+	status = 0;
+	for (size = PAGE_SIZE; size <= MEM_SIZE; size += PAGE_SIZE) {
+		status += *((int *)(addr + size - PAGE_SIZE));
+	}
+
+	if (status != *sum) {
+		fail("checksum mismatch: %x %x\n", status, *sum);
+		return 1;
+	}
+
+	pass();
+
+	return 0;
+}