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[RFC PATCH v8 0/5] IPC: checkpoint/restore in userspace enhancements [message #48600] Wed, 24 October 2012 15:34 Go to next message
Stanislav Kinsbursky is currently offline  Stanislav Kinsbursky
Messages: 683
Registered: October 2011
Senior Member
From: *parallels.com
v8:
This respin of the patch set was significantly reworked. Most part of new API
was replaced by sysctls (by one per messages, semaphores and shared memory),
allowing to preset desired id for next new IPC object.

This patch set is aimed to provide additional functionality for all IPC
objects, which is required for migration of these objects by user-space
checkpoint/restore utils (CRIU).

The main problem here was impossibility to set up object id. This patch set
solves the problem by adding new sysctls for preset of desired id for new IPC
object.

Another problem was to peek messages from queues without deleting them.
This was achived by introducing of new MSG_COPY flag for sys_msgrcv(). If
MSG_COPY flag is set, then msgtyp is interpreted as message number.

The following series implements...

---

Stanislav Kinsbursky (5):
ipc: remove forced assignment of selected message
ipc: add sysctl to specify desired next object id
ipc: message queue receive cleanup
ipc: message queue copy feature introduced
test: IPC message queue copy feture test


include/linux/ipc_namespace.h | 1
include/linux/msg.h | 5 -
include/uapi/linux/msg.h | 1
ipc/compat.c | 45 +++----
ipc/ipc_sysctl.c | 28 ++++
ipc/msg.c | 99 +++++++++++----
ipc/msgutil.c | 38 ++++++
ipc/util.c | 16 ++
ipc/util.h | 2
tools/testing/selftests/ipc/Makefile | 25 ++++
tools/testing/selftests/ipc/msgque.c | 231 ++++++++++++++++++++++++++++++++++
11 files changed, 432 insertions(+), 59 deletions(-)
create mode 100644 tools/testing/selftests/ipc/Makefile
create mode 100644 tools/testing/selftests/ipc/msgque.c
[PATCH v8 5/5] test: IPC message queue copy feture test [message #48601 is a reply to message #48600] Wed, 24 October 2012 15:35 Go to previous messageGo to next message
Stanislav Kinsbursky is currently offline  Stanislav Kinsbursky
Messages: 683
Registered: October 2011
Senior Member
From: *parallels.com
This test can be used to check wheither kernel supports IPC message queue copy
and restore features (required by CRIU project).

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
---
tools/testing/selftests/ipc/Makefile | 25 ++++
tools/testing/selftests/ipc/msgque.c | 231 ++++++++++++++++++++++++++++++++++
2 files changed, 256 insertions(+), 0 deletions(-)
create mode 100644 tools/testing/selftests/ipc/Makefile
create mode 100644 tools/testing/selftests/ipc/msgque.c

diff --git a/tools/testing/selftests/ipc/Makefile b/tools/testing/selftests/ipc/Makefile
new file mode 100644
index 0000000..5386fd7
--- /dev/null
+++ b/tools/testing/selftests/ipc/Makefile
@@ -0,0 +1,25 @@
+uname_M := $(shell uname -m 2>/dev/null || echo not)
+ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/i386/)
+ifeq ($(ARCH),i386)
+ ARCH := X86
+ CFLAGS := -DCONFIG_X86_32 -D__i386__
+endif
+ifeq ($(ARCH),x86_64)
+ ARCH := X86
+ CFLAGS := -DCONFIG_X86_64 -D__x86_64__
+endif
+
+CFLAGS += -I../../../../usr/include/
+
+all:
+ifeq ($(ARCH),X86)
+ gcc $(CFLAGS) msgque.c -o msgque_test
+else
+ echo "Not an x86 target, can't build msgque selftest"
+endif
+
+run_tests: all
+ ./msgque_test
+
+clean:
+ rm -fr ./msgque_test
diff --git a/tools/testing/selftests/ipc/msgque.c b/tools/testing/selftests/ipc/msgque.c
new file mode 100644
index 0000000..e2d6a64
--- /dev/null
+++ b/tools/testing/selftests/ipc/msgque.c
@@ -0,0 +1,231 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <linux/msg.h>
+
+#define MAX_MSG_SIZE 32
+
+struct msg1 {
+ int msize;
+ long mtype;
+ char mtext[MAX_MSG_SIZE];
+};
+
+#define TEST_STRING "Test sysv5 msg"
+#define MSG_TYPE 1
+
+#define ANOTHER_TEST_STRING "Yet another test sysv5 msg"
+#define ANOTHER_MSG_TYPE 26538
+
+struct msgque_data {
+ int msq_id;
+ int qbytes;
+ int kern_id;
+ int qnum;
+ int mode;
+ struct msg1 *messages;
+};
+
+int restore_queue(struct msgque_data *msgque)
+{
+ struct msqid_ds ds;
+ int id, i;
+
+ id = msgget(msgque->msq_id,
+ msgque->mode | IPC_CREAT | IPC_EXCL | IPC_PRESET);
+ if (id == -1) {
+ printf("Failed to create queue\n");
+ return -errno;
+ }
+
+ if (id != msgque->msq_id) {
+ printf("Failed to preset id (%d instead of %d)\n",
+ id, msgque->msq_id);
+ return -EFAULT;
+ }
+
+ if (msgctl(id, MSG_STAT, &ds) < 0) {
+ printf("Failed to stat queue\n");
+ return -errno;
+ }
+
+ ds.msg_perm.key = msgque->msq_id;
+ ds.msg_qbytes = msgque->qbytes;
+ if (msgctl(id, MSG_SET, &ds) < 0) {
+ printf("Failed to update message key\n");
+ return -errno;
+ }
+
+ for (i = 0; i < msgque->qnum; i++) {
+ if (msgsnd(msgque->msq_id, &msgque->messages[i].mtype, msgque->messages[i].msize, IPC_NOWAIT) != 0) {
+ printf("msgsnd failed (%m)\n");
+ return -errno;
+ };
+ }
+ return 0;
+}
+
+int check_and_destroy_queue(struct msgque_data *msgque)
+{
+ struct msg1 message;
+ int cnt = 0, ret;
+
+ while (1) {
+ ret = msgrcv(msgque->msq_id, &message.mtype, MAX_MSG_SIZE, 0, IPC_NOWAIT);
+ if (ret < 0) {
+ if (errno == ENOMSG)
+ break;
+ printf("Failed to read IPC message: %m\n");
+ ret = -errno;
+ goto err;
+ }
+ if (ret != msgque->messages[cnt].msize) {
+ printf("Wrong message size: %d (expected %d)\n", ret, msgque->messages[cnt].msize);
+ ret = -EINVAL;
+ goto err;
+ }
+ if (message.mtype != msgque->messages[cnt].mtype) {
+ printf("Wrong message type\n");
+ ret = -EINVAL;
+ goto err;
+ }
+ if (memcmp(message.mtext, msgque->messages[cnt].mtext, ret)) {
+ printf("Wrong message content\n");
+ ret = -EINVAL;
+ goto err;
+ }
+ cnt++;
+ }
+
+ if (cnt != msgque->qnum) {
+ printf("Wrong message number\n");
+ ret = -EINVAL;
+ goto err;
+ }
+
+ ret = 0;
+err:
+ if (msgctl(msgque->msq_id, IPC_RMID, 0)) {
+ printf("Failed to destroy queue: %d\n", -errno);
+ return -errno;
+ }
+ return ret;
+}
+
+int dump_queue(struct msgque_data *msgque)
+{
+ struct msqid_ds ds;
+ int i, ret;
+
+ for (msgque->kern_id = 0; msgque->kern_id < 256; msgque->kern_id++) {
+ ret = msgctl(msgque->kern_id, MSG_STAT, &ds);
+ if (ret < 0) {
+ if (errno == -EINVAL)
+ continue;
+ printf("Failed to get stats for IPC queue with id %d\n", msgque->kern_id);
+ return -errno;
+ }
+
+ if (ret == msgque->msq_id)
+ break;
+ }
+
+ msgque->messages = malloc(sizeof(struct msg1) * ds.msg_qnum);
+ if (msgque->messages == NULL) {
+ printf("Failed to get stats for IPC queue\n");
+ return -ENOMEM;
+ }
+
+ msgque->qnum = ds.msg_qnum;
+ msgque->mode = ds.msg_perm.mode;
+ msgque->qbytes = ds.msg_qbytes;
+
+ for (i = 0; i < msgque->qnum; i++) {
+ ret = msgrcv(msgque->msq_id, &msgque->messages[i].mtype, MAX_MSG_SIZE, i, IPC_NOWAIT | MSG_COPY);
+ if (ret < 0) {
+ printf("Failed to copy IPC message: %m (%d)\n", errno);
+ return -errno;
+ }
+ msgque->messages[i].msize = ret;
+ }
+ return 0;
+}
+
+int fill_msgque(struct msgque_data *msgque)
+{
+ struct msg1 msgbuf;
+
+ msgbuf.mtype = MSG_TYPE;
+ memcpy(msgbuf.mtext, TEST_STRING, sizeof(TEST_STRING));
+ if (msgsnd(msgque->msq_id, &msgbuf.mtype, sizeof(TEST_STRING), IPC_NOWAIT) != 0) {
+ printf("First message send failed (%m)\n");
+ return -errno;
+ };
+
+ msgbuf.mtype = ANOTHER_MSG_TYPE;
+ memcpy(msgbuf.mtext, ANOTHER_TEST_STRING, sizeof(ANOTHER_TEST_STRING));
+ if (msgsnd(msgque->msq_id, &msgbuf.mtype, sizeof(ANOTHER_TEST_STRING), IPC_NOWAIT) != 0) {
+ printf("Second message send failed (%m)\n");
+ return -errno;
+ };
+ return 0;
+}
+
+int main (int argc, char **argv)
+{
+ key_t key;
+ int msg, pid, err;
+ struct msgque_data msgque;
+
+ key = ftok(argv[0], 822155650);
+ if (key == -1) {
+ printf("Can't make key\n");
+ return -errno;
+ }
+
+ msgque.msq_id = msgget(key, IPC_CREAT | IPC_EXCL | 0666);
+ if (msgque.msq_id == -1) {
+ printf("Can't create queue\n");
+ goto err_out;
+ }
+
+ err = fill_msgque(&msgque);
+ if (err) {
+ printf("Failed to fill queue\n");
+ goto err_destroy;
+ }
+
+ err = dump_queue(&msgque);
+ if (err) {
+ printf("Failed to dump queue\n");
+ goto err_destroy;
+ }
+
+ err = check_and_destroy_queue(&msgque);
+ if (err) {
+ printf("Failed to check and destroy queue\n");
+ goto err_out;
+ }
+
+ err = restore_queue(&msgque);
+ if (err) {
+ printf("Failed to restore queue\n");
+ goto err_destroy;
+ }
+
+ err = check_and_destroy_queue(&msgque);
+ if (err) {
+ printf("Failed to test queue\n");
+ goto err_out;
+ }
+ return 0;
+
+err_destroy:
+ if (msgctl(msgque.msq_id, IPC_RMID, 0)) {
+ printf("Failed to destroy queue: %d\n", -errno);
+ return -errno;
+ }
+err_out:
+ return err;
+}
Re: [RFC PATCH v8 0/5] IPC: checkpoint/restore in userspace enhancements [message #48611 is a reply to message #48600] Wed, 24 October 2012 21:42 Go to previous message
akpm is currently offline  akpm
Messages: 224
Registered: March 2007
Senior Member
From: *parallels.com
On Wed, 24 Oct 2012 19:34:51 +0400
Stanislav Kinsbursky <skinsbursky@parallels.com> wrote:

> This respin of the patch set was significantly reworked. Most part of new API
> was replaced by sysctls (by one per messages, semaphores and shared memory),
> allowing to preset desired id for next new IPC object.
>
> This patch set is aimed to provide additional functionality for all IPC
> objects, which is required for migration of these objects by user-space
> checkpoint/restore utils (CRIU).
>
> The main problem here was impossibility to set up object id. This patch set
> solves the problem by adding new sysctls for preset of desired id for new IPC
> object.
>
> Another problem was to peek messages from queues without deleting them.
> This was achived by introducing of new MSG_COPY flag for sys_msgrcv(). If
> MSG_COPY flag is set, then msgtyp is interpreted as message number.

OK, thanks, I grabbed these. They're not the worst c/r patches I've
ever seen ;)

I'm not seeing any evidence that anyone else has reviewed or tested
these?
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