colo: Setup ram cache in normal migration path
Since 121ccedc2b migration: block incoming colo when capability is disabled x-colo capability needs to be always enabled on the incoming side. So migration_incoming_colo_enabled() and migrate_colo() are equivalent with migrate_colo() being easier to reason about since it is always true during the whole migration. Use migrate_colo() to initialize the ram cache in the normal migration path. Reviewed-by: Fabiano Rosas <farosas@suse.de> Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: Lukas Straub <lukasstraub2@web.de> Link: https://lore.kernel.org/qemu-devel/20260302-colo_unit_test_multifd-v11-3-d653fb3b1d80@web.de Signed-off-by: Fabiano Rosas <farosas@suse.de>
Lukas Straub committed
Mar 2, 2026 at 12:43 UTC
663692f0a30c3fb525f2d81883db231ea1a5d402
2 files changed
+15
-17
migration/migration.c
+14
-4
@@ -630,10 +630,6 @@ int migration_incoming_enable_colo(Error **errp)
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return -EINVAL;
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}
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- if (ram_block_discard_disable(true)) {
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- error_setg(errp, "COLO: cannot disable RAM discard");
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- return -EBUSY;
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- }
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migration_colo_enabled = true;
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return 0;
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}
@@ -770,6 +766,20 @@ process_incoming_migration_co(void *opaque)
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assert(mis->from_src_file);
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+ if (migrate_colo()) {
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+ if (ram_block_discard_disable(true)) {
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+ error_setg(&local_err, "COLO: cannot disable RAM discard");
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+ goto fail;
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+ }
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+
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+ ret = colo_init_ram_cache(&local_err);
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+ if (ret) {
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+ error_prepend(&local_err, "failed to init colo RAM cache: %d: ",
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+ ret);
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+ goto fail;
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+ }
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+ }
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+
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mis->largest_page_size = qemu_ram_pagesize_largest();
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postcopy_state_set(POSTCOPY_INCOMING_NONE);
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migrate_set_state(&mis->state, MIGRATION_STATUS_SETUP,
migration/savevm.c
+1
-13
@@ -2427,19 +2427,7 @@ static int loadvm_process_enable_colo(MigrationIncomingState *mis,
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Error **errp)
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{
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ERRP_GUARD();
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- int ret;
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-
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- ret = migration_incoming_enable_colo(errp);
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- if (ret < 0) {
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- return ret;
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- }
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-
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- ret = colo_init_ram_cache(errp);
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- if (ret) {
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- error_prepend(errp, "failed to init colo RAM cache: %d: ", ret);
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- migration_incoming_disable_colo();
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- }
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- return ret;
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+ return migration_incoming_enable_colo(errp);
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}
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static int loadvm_postcopy_handle_switchover_start(Error **errp)