[PATCH v6 09/13] multifd: Add property to enable/disable zero_page

[Juan Quintela]

Signed-off-by: Juan Quintela <quint...@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
---
 migration/migration.h |  3 +++
 hw/core/machine.c     |  4 +++-
 migration/migration.c | 11 +++++++++++
 3 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/migration/migration.h b/migration/migration.h
index a863032b71..068e66ca9a 100644
--- a/migration/migration.h
+++ b/migration/migration.h
@@ -332,6 +332,8 @@ struct MigrationState {
      * This save hostname when out-going migration starts
      */
     char *hostname;
+    /* Use multifd channel to send zero pages */
+    bool multifd_zero_pages;
 };
 
 void migrate_set_state(int *state, int old_state, int new_state);
@@ -374,6 +376,7 @@ int migrate_multifd_channels(void);
 MultiFDCompression migrate_multifd_compression(void);
 int migrate_multifd_zlib_level(void);
 int migrate_multifd_zstd_level(void);
+bool migrate_use_multifd_zero_page(void);
 
 int migrate_use_xbzrle(void);
 uint64_t migrate_xbzrle_cache_size(void);
diff --git a/hw/core/machine.c b/hw/core/machine.c
index 700c1e76b8..d02977d5df 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -37,7 +37,9 @@
 #include "hw/virtio/virtio.h"
 #include "hw/virtio/virtio-pci.h"
 
-GlobalProperty hw_compat_7_0[] = {};
+GlobalProperty hw_compat_7_0[] = {
+    { "migration", "multifd-zero-pages", "false" },
+};
 const size_t hw_compat_7_0_len = G_N_ELEMENTS(hw_compat_7_0);
 
 GlobalProperty hw_compat_6_2[] = {
diff --git a/migration/migration.c b/migration/migration.c
index 5a31b23bd6..7e591990ef 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -2517,6 +2517,15 @@ bool migrate_use_multifd(void)
     return s->enabled_capabilities[MIGRATION_CAPABILITY_MULTIFD];
 }
 
+bool migrate_use_multifd_zero_page(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->multifd_zero_pages;
+}
+
 bool migrate_pause_before_switchover(void)
 {
     MigrationState *s;
@@ -4164,6 +4173,8 @@ static Property migration_properties[] = {
                       clear_bitmap_shift, CLEAR_BITMAP_SHIFT_DEFAULT),
 
     /* Migration parameters */
+    DEFINE_PROP_BOOL("multifd-zero-pages", MigrationState,
+                      multifd_zero_pages, true),
     DEFINE_PROP_UINT8("x-compress-level", MigrationState,
                       parameters.compress_level,
                       DEFAULT_MIGRATE_COMPRESS_LEVEL),
-- 
2.35.1