From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:34412) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Zw9sS-0003nO-MR for qemu-devel@nongnu.org; Tue, 10 Nov 2015 09:26:31 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Zw9sR-0000r8-NK for qemu-devel@nongnu.org; Tue, 10 Nov 2015 09:26:28 -0500 Received: from mx1.redhat.com ([209.132.183.28]:45940) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Zw9sR-0000r2-BL for qemu-devel@nongnu.org; Tue, 10 Nov 2015 09:26:27 -0500 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) by mx1.redhat.com (Postfix) with ESMTPS id 187FE8EA49 for ; Tue, 10 Nov 2015 14:26:27 +0000 (UTC) From: Juan Quintela Date: Tue, 10 Nov 2015 15:25:13 +0100 Message-Id: <1447165546-27784-25-git-send-email-quintela@redhat.com> In-Reply-To: <1447165546-27784-1-git-send-email-quintela@redhat.com> References: <1447165546-27784-1-git-send-email-quintela@redhat.com> Subject: [Qemu-devel] [PULL 24/57] Add migration-capability boolean for postcopy-ram. List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: amit.shah@redhat.com, dgilbert@redhat.com From: "Dr. David Alan Gilbert" The 'postcopy ram' capability allows postcopy migration of RAM; note that the migration starts off in precopy mode until postcopy mode is triggered (see the migrate_start_postcopy patch later in the series). Signed-off-by: Dr. David Alan Gilbert Reviewed-by: Juan Quintela Reviewed-by: Amit Shah Signed-off-by: Juan Quintela --- include/migration/migration.h | 1 + migration/migration.c | 23 +++++++++++++++++++++++ qapi-schema.json | 6 +++++- 3 files changed, 29 insertions(+), 1 deletion(-) diff --git a/include/migration/migration.h b/include/migration/migration.h index 3dc95f4..4ed7931 100644 --- a/include/migration/migration.h +++ b/include/migration/migration.h @@ -186,6 +186,7 @@ void migrate_add_blocker(Error *reason); */ void migrate_del_blocker(Error *reason); +bool migrate_postcopy_ram(void); bool migrate_zero_blocks(void); bool migrate_auto_converge(void); diff --git a/migration/migration.c b/migration/migration.c index e4f91a9..f849f89 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -578,6 +578,20 @@ void qmp_migrate_set_capabilities(MigrationCapabilityStatusList *params, for (cap = params; cap; cap = cap->next) { s->enabled_capabilities[cap->value->capability] = cap->value->state; } + + if (migrate_postcopy_ram()) { + if (migrate_use_compression()) { + /* The decompression threads asynchronously write into RAM + * rather than use the atomic copies needed to avoid + * userfaulting. It should be possible to fix the decompression + * threads for compatibility in future. + */ + error_report("Postcopy is not currently compatible with " + "compression"); + s->enabled_capabilities[MIGRATION_CAPABILITY_X_POSTCOPY_RAM] = + false; + } + } } void qmp_migrate_set_parameters(bool has_compress_level, @@ -956,6 +970,15 @@ void qmp_migrate_set_downtime(double value, Error **errp) max_downtime = (uint64_t)value; } +bool migrate_postcopy_ram(void) +{ + MigrationState *s; + + s = migrate_get_current(); + + return s->enabled_capabilities[MIGRATION_CAPABILITY_X_POSTCOPY_RAM]; +} + bool migrate_auto_converge(void) { MigrationState *s; diff --git a/qapi-schema.json b/qapi-schema.json index e18f14c..8638d42 100644 --- a/qapi-schema.json +++ b/qapi-schema.json @@ -540,11 +540,15 @@ # @auto-converge: If enabled, QEMU will automatically throttle down the guest # to speed up convergence of RAM migration. (since 1.6) # +# @x-postcopy-ram: Start executing on the migration target before all of RAM has +# been migrated, pulling the remaining pages along as needed. NOTE: If +# the migration fails during postcopy the VM will fail. (since 2.5) +# # Since: 1.2 ## { 'enum': 'MigrationCapability', 'data': ['xbzrle', 'rdma-pin-all', 'auto-converge', 'zero-blocks', - 'compress', 'events'] } + 'compress', 'events', 'x-postcopy-ram'] } ## # @MigrationCapabilityStatus -- 2.5.0