The only remaining special case is postcopy. It cannot handle
concurrent discards yet, which would result in requesting already sent
pages from the source. Special-case it in virtio-balloon instead.
Introduce migration_in_incoming_postcopy(), to find out if incoming
postcopy is active.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Juan Quintela <quintela@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <
20200626072248.78761-7-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
static QEMUBalloonEvent *balloon_event_fn;
static QEMUBalloonStatus *balloon_stat_fn;
static void *balloon_opaque;
-static int balloon_inhibit_count;
-
-bool qemu_balloon_is_inhibited(void)
-{
- return atomic_read(&balloon_inhibit_count) > 0 ||
- ram_block_discard_is_disabled();
-}
-
-void qemu_balloon_inhibit(bool state)
-{
- if (state) {
- atomic_inc(&balloon_inhibit_count);
- } else {
- atomic_dec(&balloon_inhibit_count);
- }
-
- assert(atomic_read(&balloon_inhibit_count) >= 0);
-}
static bool have_balloon(Error **errp)
{
return pbp->base_gpa == base_gpa;
}
+static bool virtio_balloon_inhibited(void)
+{
+ /* Postcopy cannot deal with concurrent discards, so it's special. */
+ return ram_block_discard_is_disabled() || migration_in_incoming_postcopy();
+}
+
static void balloon_inflate_page(VirtIOBalloon *balloon,
MemoryRegion *mr, hwaddr mr_offset,
PartiallyBalloonedPage *pbp)
* accessible by another device or process, or if the guest is
* expecting it to retain a non-zero value.
*/
- if (qemu_balloon_is_inhibited() || dev->poison_val) {
+ if (virtio_balloon_inhibited() || dev->poison_val) {
goto skip_element;
}
trace_virtio_balloon_handle_output(memory_region_name(section.mr),
pa);
- if (!qemu_balloon_is_inhibited()) {
+ if (!virtio_balloon_inhibited()) {
if (vq == s->ivq) {
balloon_inflate_page(s, section.mr,
section.offset_within_region, &pbp);
/* ...and after the device transmission */
bool migration_in_postcopy_after_devices(MigrationState *);
void migration_global_dump(Monitor *mon);
+/* True if incomming migration entered POSTCOPY_INCOMING_DISCARD */
+bool migration_in_incoming_postcopy(void);
/* migration/block-dirty-bitmap.c */
void dirty_bitmap_mig_init(void);
int qemu_add_balloon_handler(QEMUBalloonEvent *event_func,
QEMUBalloonStatus *stat_func, void *opaque);
void qemu_remove_balloon_handler(void *opaque);
-bool qemu_balloon_is_inhibited(void);
-void qemu_balloon_inhibit(bool state);
#endif
return migration_in_postcopy() && s->postcopy_after_devices;
}
+bool migration_in_incoming_postcopy(void)
+{
+ PostcopyState ps = postcopy_state_get();
+
+ return ps >= POSTCOPY_INCOMING_DISCARD && ps < POSTCOPY_INCOMING_END;
+}
+
bool migration_is_idle(void)
{
MigrationState *s = current_migration;
#include "qemu/notify.h"
#include "qemu/rcu.h"
#include "sysemu/sysemu.h"
-#include "sysemu/balloon.h"
#include "qemu/error-report.h"
#include "trace.h"
#include "hw/boards.h"
return 0;
}
-/*
- * Manage a single vote to the QEMU balloon inhibitor for all postcopy usage,
- * last caller wins.
- */
-static void postcopy_balloon_inhibit(bool state)
-{
- static bool cur_state = false;
-
- if (state != cur_state) {
- qemu_balloon_inhibit(state);
- cur_state = state;
- }
-}
-
/*
* At the end of a migration where postcopy_ram_incoming_init was called.
*/
mis->have_fault_thread = false;
}
- postcopy_balloon_inhibit(false);
-
if (enable_mlock) {
if (os_mlock() < 0) {
error_report("mlock: %s", strerror(errno));
}
memset(mis->postcopy_tmp_zero_page, '\0', mis->largest_page_size);
- /*
- * Ballooning can mark pages as absent while we're postcopying
- * that would cause false userfaults.
- */
- postcopy_balloon_inhibit(true);
-
trace_postcopy_ram_enable_notify();
return 0;