File xl-save-pc.patch of Package xen
References: bug#1176189
Usage of xl save -p|-c will suspend the domU.
As a result the monitoring xl process with get a LIBXL_EVENT_TYPE_DOMAIN_SHUTDOWN/LIBXL_SHUTDOWN_REASON_SUSPEND event.
This will cause it to exit because it does not know the -p/-c flags were used to keep the domU active.
As a result the final shutdown will not destroy the domU.
Write a flag to xenstore to let the monitoring process know about the usage of -p/-c.
Remove the flag once the suspend is done.
Recognize the flag in the monitoring process.
Keep going if the flag is seen.
Watch again for @releaseDomain events.
Keep going if the event type and shutdown reason remains the same.
---
tools/xl/Makefile | 3 ++-
tools/xl/xl.h | 1 +
tools/xl/xl_saverestore.c | 15 ++++++++++++
tools/xl/xl_vmcontrol.c | 48 +++++++++++++++++++++++++++++++++++++++
4 files changed, 66 insertions(+), 1 deletion(-)
--- a/tools/xl/Makefile
+++ b/tools/xl/Makefile
@@ -26,6 +26,7 @@ XL_OBJS += xl_vmcontrol.o xl_saverestore
XL_OBJS += xl_vdispl.o xl_vsnd.o xl_vkb.o
$(XL_OBJS): CFLAGS += $(CFLAGS_libxentoollog)
+$(XL_OBJS): CFLAGS += $(CFLAGS_libxenstore)
$(XL_OBJS): CFLAGS += $(CFLAGS_XL)
$(XL_OBJS): CFLAGS += -include $(XEN_ROOT)/tools/config.h # libxl_json.h needs it.
@@ -33,7 +34,7 @@ $(XL_OBJS): CFLAGS += -include $(XEN_ROO
all: xl
xl: $(XL_OBJS)
- $(CC) $(LDFLAGS) -o $@ $(XL_OBJS) $(LDLIBS_libxenutil) $(LDLIBS_libxenlight) $(LDLIBS_libxentoollog) -lyajl $(APPEND_LDFLAGS)
+ $(CC) $(LDFLAGS) -o $@ $(XL_OBJS) $(LDLIBS_libxenutil) $(LDLIBS_libxenlight) $(LDLIBS_libxentoollog) $(LDLIBS_libxenstore) -lyajl $(APPEND_LDFLAGS)
.PHONY: install
install: all
--- a/tools/xl/xl.h
+++ b/tools/xl/xl.h
@@ -303,6 +303,7 @@ typedef enum {
DOMAIN_RESTART_SOFT_RESET, /* Soft reset should be performed */
} domain_restart_type;
+#define XL_SAVE_PAUSE_CHECKPOINT "suse-xl-save-pc"
extern void printf_info_sexp(int domid, libxl_domain_config *d_config, FILE *fh);
extern void apply_global_affinity_masks(libxl_domain_type type,
libxl_bitmap *vcpu_affinity_array,
--- a/tools/xl/xl_saverestore.c
+++ b/tools/xl/xl_saverestore.c
@@ -21,6 +21,7 @@
#include <time.h>
#include <unistd.h>
+#include <xenstore.h>
#include <libxl.h>
#include <libxl_utils.h>
#include <libxlutil.h>
@@ -127,6 +128,8 @@ static int save_domain(uint32_t domid, i
const char *filename, int checkpoint,
int leavepaused, const char *override_config_file)
{
+ struct xs_handle *xsh = NULL;
+ char path[80];
int fd;
uint8_t *config_data;
int config_len;
@@ -144,12 +147,24 @@ static int save_domain(uint32_t domid, i
fprintf(stderr, "Failed to open temp file %s for writing\n", filename);
exit(EXIT_FAILURE);
}
+ if (leavepaused || checkpoint)
+ {
+ snprintf(path, sizeof(path), "/libxl/%u/" XL_SAVE_PAUSE_CHECKPOINT, domid);
+ xsh = xs_open(0);
+ if (xsh)
+ xs_write(xsh, XBT_NULL, path, leavepaused ? "p" : "c", 1);
+ }
save_domain_core_writeconfig(fd, filename, config_data, config_len);
int rc = libxl_domain_suspend_suse(ctx, domid, fd, &props, NULL);
close(fd);
+ if (xsh) {
+ xs_rm(xsh, XBT_NULL, path);
+ xs_close(xsh);
+ }
+
if (rc < 0) {
fprintf(stderr, "Failed to save domain, resuming domain\n");
libxl_domain_resume(ctx, domid, 1, 0);
--- a/tools/xl/xl_vmcontrol.c
+++ b/tools/xl/xl_vmcontrol.c
@@ -22,6 +22,7 @@
#include <time.h>
#include <unistd.h>
+#include <xenstore.h>
#include <libxl.h>
#include <libxl_utils.h>
#include <libxlutil.h>
@@ -668,6 +669,10 @@ int create_domain(struct domain_create *
int migrate_fd = dom_info->migrate_fd;
bool config_in_json;
+ libxl_event_type type = 0;
+ uint8_t shutdown_reason = 0;
+ bool is_in_suspend = false;
+
int i;
int need_daemon = daemonize;
int ret, rc;
@@ -1034,6 +1039,24 @@ start:
ret = domain_wait_event(domid, &event);
if (ret) goto out;
+ if (is_in_suspend) {
+ if ( type == event->type && event->u.domain_shutdown.shutdown_reason == shutdown_reason) {
+ struct timespec req = { .tv_nsec = 123456789, };
+ libxl_evdisable_domain_death(ctx, deathw);
+ deathw = NULL;
+ ret = libxl_evenable_domain_death(ctx, domid, 0, &deathw);
+ if (ret) goto out;
+ libxl_event_free(ctx, event);
+ LOG("Domain %u still suspended", domid);
+ nanosleep(&req, NULL);
+ continue;
+ }
+ is_in_suspend = false;
+ LOG("Domain %u left suspend state", domid);
+ }
+ type = event->type;
+ shutdown_reason = event->u.domain_shutdown.shutdown_reason;
+
switch (event->type) {
case LIBXL_EVENT_TYPE_DOMAIN_SHUTDOWN:
@@ -1095,14 +1118,39 @@ start:
goto start;
case DOMAIN_RESTART_NONE:
+ {
+ struct xs_handle *xsh = xs_open(0);
+
+ if (xsh) {
+ char path[80];
+ unsigned int len = 0;
+ char *val;
+
+ snprintf(path, sizeof(path), "/libxl/%u/" XL_SAVE_PAUSE_CHECKPOINT, domid);
+ val = xs_read(xsh, XBT_NULL, path, &len);
+ xs_close(xsh);
+ LOG("Got %p '%s' from %s, len %u", val, val ?:"", path, len);
+ free(val);
+ if (val)
+ {
+ is_in_suspend = true;
+ libxl_evdisable_domain_death(ctx, deathw);
+ deathw = NULL;
+ ret = libxl_evenable_domain_death(ctx, domid, 0, &deathw);
+ if (ret) goto out;
+ break;
+ }
+ }
LOG("Done. Exiting now");
libxl_event_free(ctx, event);
ret = 0;
goto out;
+ }
default:
abort();
}
+ break;
case LIBXL_EVENT_TYPE_DOMAIN_DEATH:
LOG("Domain %u has been destroyed.", domid);
