On Thu, Oct 24, 2019 at 05:09:22AM -0400, Jagannathan Raman wrote:
Collect the VMSD from remote process on the source and save
it to the channel leading to the destination
Signed-off-by: Elena Ufimtseva <address@hidden>
Signed-off-by: John G Johnson <address@hidden>
Signed-off-by: Jagannathan Raman <address@hidden>
---
New patch in v4
hw/proxy/qemu-proxy.c | 132 ++++++++++++++++++++++++++++++++++++++++++
include/hw/proxy/qemu-proxy.h | 2 +
include/io/mpqemu-link.h | 1 +
3 files changed, 135 insertions(+)
diff --git a/hw/proxy/qemu-proxy.c b/hw/proxy/qemu-proxy.c
index 623a6c5..ce72e6a 100644
--- a/hw/proxy/qemu-proxy.c
+++ b/hw/proxy/qemu-proxy.c
@@ -52,6 +52,14 @@
#include "util/event_notifier-posix.c"
#include "hw/boards.h"
#include "include/qemu/log.h"
+#include "io/channel.h"
+#include "migration/qemu-file-types.h"
+#include "qapi/error.h"
+#include "io/channel-util.h"
+#include "migration/qemu-file-channel.h"
+#include "migration/qemu-file.h"
+#include "migration/migration.h"
+#include "migration/vmstate.h"
QEMUTimer *hb_timer;
static void pci_proxy_dev_realize(PCIDevice *dev, Error **errp);
@@ -62,6 +70,9 @@ static void stop_heartbeat_timer(void);
static void childsig_handler(int sig, siginfo_t *siginfo, void *ctx);
static void broadcast_msg(MPQemuMsg *msg, bool need_reply);
+#define PAGE_SIZE getpagesize()
+uint8_t *mig_data;
+
static void childsig_handler(int sig, siginfo_t *siginfo, void *ctx)
{
/* TODO: Add proper handler. */
@@ -357,14 +368,135 @@ static void pci_proxy_dev_inst_init(Object *obj)
dev->mem_init = false;
}
+typedef struct {
+ QEMUFile *rem;
+ PCIProxyDev *dev;
+} proxy_mig_data;
+
+static void *proxy_mig_out(void *opaque)
+{
+ proxy_mig_data *data = opaque;
+ PCIProxyDev *dev = data->dev;
+ uint8_t byte;
+ uint64_t data_size = PAGE_SIZE;
+
+ mig_data = g_malloc(data_size);
+
+ while (true) {
+ byte = qemu_get_byte(data->rem);
There is a pretty large set of APIs hiding behind the qemu_get_byte
call, which does not give me confidence that...
+ mig_data[dev->migsize++] = byte;
+ if (dev->migsize == data_size) {
+ data_size += PAGE_SIZE;
+ mig_data = g_realloc(mig_data, data_size);
+ }
+ }
+
+ return NULL;
+}
+
+static int proxy_pre_save(void *opaque)
+{
+ PCIProxyDev *pdev = opaque;
+ proxy_mig_data *mig_data;
+ QEMUFile *f_remote;
+ MPQemuMsg msg = {0};
+ QemuThread thread;
+ Error *err = NULL;
+ QIOChannel *ioc;
+ uint64_t size;
+ int fd[2];
+
+ if (socketpair(AF_UNIX, SOCK_STREAM, 0, fd)) {
+ return -1;
+ }
+
+ ioc = qio_channel_new_fd(fd[0], &err);
+ if (err) {
+ error_report_err(err);
+ return -1;
+ }
+
+ qio_channel_set_name(QIO_CHANNEL(ioc), "PCIProxyDevice-mig");
+
+ f_remote = qemu_fopen_channel_input(ioc);
+
+ pdev->migsize = 0;
+
+ mig_data = g_malloc0(sizeof(proxy_mig_data));
+ mig_data->rem = f_remote;
+ mig_data->dev = pdev;
+
+ qemu_thread_create(&thread, "Proxy MIG_OUT", proxy_mig_out, mig_data,
+ QEMU_THREAD_DETACHED);
+
+ msg.cmd = START_MIG_OUT;
+ msg.bytestream = 0;
+ msg.num_fds = 2;
+ msg.fds[0] = fd[1];
+ msg.fds[1] = GET_REMOTE_WAIT;
+
+ mpqemu_msg_send(pdev->mpqemu_link, &msg, pdev->mpqemu_link->com);
+ size = wait_for_remote(msg.fds[1]);
+ PUT_REMOTE_WAIT(msg.fds[1]);
+
+ assert(size != ULLONG_MAX);
+
+ /*
+ * migsize is being update by a separate thread. Using volatile to
+ * instruct the compiler to fetch the value of this variable from
+ * memory during every read
+ */
+ while (*((volatile uint64_t *)&pdev->migsize) < size) {
+ }
+
+ qemu_thread_cancel(&thread);
....this is a safe way to stop the thread executing without
resulting in memory being leaked.
In addition thread cancellation is asynchronous, so the thread
may still be using the QEMUFile object while....
+ qemu_fclose(f_remote);