This test forks off several children in various states to ensure that the
IPC namespace information is properly restored after restart.
Cc: orenl@xxxxxxxxxxxxxxx
Signed-off-by: Dan Smith <danms@xxxxxxxxxx>
---
Makefile | 2 +-
tst_ipcshm_multi.c | 266 ++++++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 267 insertions(+), 1 deletions(-)
create mode 100644 tst_ipcshm_multi.c
diff --git a/Makefile b/Makefile
index c847a0c..2da03bb 100644
--- a/Makefile
+++ b/Makefile
@@ -19,7 +19,7 @@ CFLAGS += -g $(WARNS) $(PATHS) $(DEBUG)
PROGS = self ckpt rstr mktree
TESTS= tst_onetask tst_multitask tst_bigmem tst_pipes tst_pipes2 tst_shmem \
- tst_ipcshm tst_ipcmsq
+ tst_ipcshm tst_ipcmsq tst_ipcshm_multi
LDLIBS = -lm
diff --git a/tst_ipcshm_multi.c b/tst_ipcshm_multi.c
new file mode 100644
index 0000000..1ef31f7
--- /dev/null
+++ b/tst_ipcshm_multi.c
@@ -0,0 +1,266 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+#include <sys/ipc.h>
+#include <sys/shm.h>
+
+#include <linux/sched.h>
+#include <sched.h>
+
+#define OUTFILE "/tmp/cr-test.out"
+#define SEG_SIZE (20 * 4096)
+#define DELAY 20
+
+int attach(unsigned char **seg, int num)
+{
+ int id;
+
+ id = shmget(123, SEG_SIZE, 0700|IPC_EXCL);
+ if (id < 0) {
+ printf("[CHILD %i] shmget: %m\n", num);
+ return -1;
+ }
+
+ *seg = shmat(id, NULL, 0);
+ if (!*seg) {
+ printf("[CHILD %i] shmat: %m\n", num);
+ return -1;
+ }
+
+ printf("[CHILD %i] Attached\n", num);
+
+ return 0;
+}
+
+int validate(unsigned char *seg, int num)
+{
+ int i;
+
+ for (i = 1; i < SEG_SIZE; i++) {
+ if (seg[i] != (unsigned char)(i % 256)) {
+ printf("[CHILD %i] Mismatch at %hhu: %hhu\n",
+ num, i, seg[i]);
+ return -1;
+ }
+ }
+
+ printf("[CHILD %i] Validated\n", num);
+
+ return 0;
+}
+
+void track(unsigned char *seg, int num)
+{
+ int i;
+
+ for (i = 0; i < 20; i++) {
+ printf("[CHILD %i] Seg[0]: %i\n", num, seg[0]);
+ sleep(1);
+ }
+}
+
+/*
+ * Attach to the shared segment *before* the checkpoint and then track
+ * the changing seg[0] position afterwards.
+ */
+int child1(void)
+{
+ unsigned char *seg;
+ int num = 1;
+
+ printf("[CHILD %i] Running\n", num);
+
+ sleep(1); /* Allow master to finish initializing the array */
+
+ if (attach(&seg, num))
+ return -1;
+
+ if (validate(seg, num))
+ return -1;
+
+ sleep(DELAY - 1); /* Wait until after the checkpoint */
+
+ track(seg, num);
+
+ return 0;
+}
+
+/*
+ * Attempt to attach to the shared segment *after* the checkpoint to
+ * verify that things are hooked up properly after restart by tracking
+ * seg[0].
+ */
+int child2(void)
+{
+ unsigned char *seg;
+ int num = 2;
+
+ printf("[CHILD %i] Running\n", num);
+
+ sleep(DELAY); /* Wait until after the checkpoint */
+
+ if (attach(&seg, num))
+ return -1;
+
+ if (validate(seg, num))
+ return -1;
+
+ track(seg, num);
+
+ return 0;
+}
+
+int child4(void);
+
+/*
+ * Detach from the parent's IPC namespace and verify that:
+ * 1. We can't attach to the parent's segment
+ * 2. We can create our own of the same ID without conflict
+ * 3. We do not see the parent's changing seg[0] after restart
+ */
+int child3(void)
+{
+ unsigned char *seg;
+ int num = 3;
+
+ if (unshare(CLONE_NEWIPC) != 0) {
+ printf("[CHILD %i] unshare(CLONE_NEWIPC): %m", num);
+ return -1;
+ }
+
+ if (fork() == 0)
+ return child4();
+
+ printf("[CHILD %i] Running (new IPC NS)\n", num);
+
+ printf("[CHILD %i] Attempting parent attach (should fail)\n", num);
+ if (!attach(&seg, num)) {
+ printf("[CHILD %i] Attached to parent's IPC!\n", num);
+ return -1;
+ }
+
+ if (shmget(123, SEG_SIZE, 0700|IPC_CREAT|IPC_EXCL) < 0) {
+ printf("[CHILD %i] Failed to create shm in namespace: %m\n",
+ num);
+ return -1;
+ }
+
+ if (attach(&seg, num))
+ return -1;
+
+ seg[0] = 123;
+
+ sleep(DELAY); /* Wait until after checkpoint, then attach */
+
+ track(seg, num);
+
+ return 0;
+}
+
+/*
+ * This child is forked from child3 under the new IPC namespace.
+ * Verify that post-restart, we do not see the changing seg[0]
+ */
+int child4(void)
+{
+ unsigned char *seg;
+ int num = 4;
+
+ printf("[CHILD %i] Running (new IPC NS)\n", num);
+
+ sleep(DELAY); /* Wait past my parent creating the IPC */
+
+ if (attach(&seg, num))
+ return -1;
+
+ track(seg, num);
+
+ return 0;
+}
+
+void shm_destroy(void)
+{
+ int id;
+
+ id = shmget(123, SEG_SIZE, 0700);
+ if (id < 0)
+ return;
+
+ if (shmctl(id, IPC_RMID, NULL) == 0)
+ printf("Deleted SHM %i\n", id);
+}
+
+int main(int argc, char *argv[])
+{
+ int id;
+ unsigned char *seg;
+ int i;
+ int pid1, pid2, pid3;
+#ifndef TEST
+ FILE *file;
+
+ close(0);
+ close(1);
+ close(2);
+
+ unlink(OUTFILE);
+ file = fopen(OUTFILE, "w+");
+ if (!file) {
+ perror("open");
+ exit(1);
+ }
+ if (dup2(0,2) < 0) {
+ perror("dup2");
+ exit(2);
+ }
+ stdout = file;
+ setlinebuf(file);
+#endif
+ shm_destroy();
+
+ pid1 = fork();
+ if (pid1 == 0)
+ return child1();
+
+ pid2 = fork();
+ if (pid2 == 0)
+ return child2();
+
+ pid3 = fork();
+ if (pid3 == 0)
+ return child3();
+
+ id = shmget(123, SEG_SIZE, 0700|IPC_CREAT|IPC_EXCL);
+ if (id < 0) {
+ perror("shmget");
+ exit(1);
+ }
+
+ seg = (unsigned char *) shmat(id, NULL, 0);
+ if(seg == ((void *) -1)) {
+ perror("shmat");
+ exit(1);
+ }
+
+ for (i = 0; i < SEG_SIZE; i++)
+ seg[i] = i;
+
+ printf("[MSTER] Waiting for checkpoint\n");
+ sleep(DELAY);
+ printf("[MSTER] Woke\n");
+
+ for (i = 0; i < 15; i++) {
+ seg[0] = i;
+ sleep(1);
+ }
+
+ if (shmdt(seg) < 0)
+ perror("shmdt");
+
+ shm_destroy();
+
+ printf("[MSTER] Completed\n");
+
+ return 0;
+}
--
1.6.0.3
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