From aef060850bd0e35aa7128e0ae3cef9d62c328314 Mon Sep 17 00:00:00 2001 From: zhanghailiang Date: Thu, 27 Oct 2016 14:43:04 +0800 Subject: COLO: Introduce state to record failover process When handling failover, COLO processes differently according to the different stage of failover process, here we introduce a global atomic variable to record the status of failover. We add four failover status to indicate the different stage of failover process. You should use the helpers to get and set the value. Signed-off-by: zhanghailiang Reviewed-by: Dr. David Alan Gilbert Reviewed-by: Amit Shah Signed-off-by: Amit Shah --- include/migration/failover.h | 5 +++++ migration/colo-failover.c | 41 +++++++++++++++++++++++++++++++++++++++++ migration/colo.c | 4 ++++ migration/trace-events | 1 + qapi-schema.json | 18 ++++++++++++++++++ 5 files changed, 69 insertions(+) diff --git a/include/migration/failover.h b/include/migration/failover.h index 3274735..7e0f36a 100644 --- a/include/migration/failover.h +++ b/include/migration/failover.h @@ -14,7 +14,12 @@ #define QEMU_FAILOVER_H #include "qemu-common.h" +#include "qapi-types.h" +void failover_init_state(void); +FailoverStatus failover_set_state(FailoverStatus old_state, + FailoverStatus new_state); +FailoverStatus failover_get_state(void); void failover_request_active(Error **errp); #endif diff --git a/migration/colo-failover.c b/migration/colo-failover.c index e31fc10..6cca039 100644 --- a/migration/colo-failover.c +++ b/migration/colo-failover.c @@ -15,22 +15,63 @@ #include "migration/failover.h" #include "qmp-commands.h" #include "qapi/qmp/qerror.h" +#include "qemu/error-report.h" +#include "trace.h" static QEMUBH *failover_bh; +static FailoverStatus failover_state; static void colo_failover_bh(void *opaque) { + int old_state; + qemu_bh_delete(failover_bh); failover_bh = NULL; + + old_state = failover_set_state(FAILOVER_STATUS_REQUIRE, + FAILOVER_STATUS_ACTIVE); + if (old_state != FAILOVER_STATUS_REQUIRE) { + error_report("Unknown error for failover, old_state = %s", + FailoverStatus_lookup[old_state]); + return; + } + /* TODO: Do failover work */ } void failover_request_active(Error **errp) { + if (failover_set_state(FAILOVER_STATUS_NONE, + FAILOVER_STATUS_REQUIRE) != FAILOVER_STATUS_NONE) { + error_setg(errp, "COLO failover is already actived"); + return; + } failover_bh = qemu_bh_new(colo_failover_bh, NULL); qemu_bh_schedule(failover_bh); } +void failover_init_state(void) +{ + failover_state = FAILOVER_STATUS_NONE; +} + +FailoverStatus failover_set_state(FailoverStatus old_state, + FailoverStatus new_state) +{ + FailoverStatus old; + + old = atomic_cmpxchg(&failover_state, old_state, new_state); + if (old == old_state) { + trace_colo_failover_set_state(FailoverStatus_lookup[new_state]); + } + return old; +} + +FailoverStatus failover_get_state(void) +{ + return atomic_read(&failover_state); +} + void qmp_x_colo_lost_heartbeat(Error **errp) { if (get_colo_mode() == COLO_MODE_UNKNOWN) { diff --git a/migration/colo.c b/migration/colo.c index 12fa0b4..6b32c91 100644 --- a/migration/colo.c +++ b/migration/colo.c @@ -232,6 +232,8 @@ static void colo_process_checkpoint(MigrationState *s) Error *local_err = NULL; int ret; + failover_init_state(); + s->rp_state.from_dst_file = qemu_file_get_return_path(s->to_dst_file); if (!s->rp_state.from_dst_file) { error_report("Open QEMUFile from_dst_file failed"); @@ -332,6 +334,8 @@ void *colo_process_incoming_thread(void *opaque) migrate_set_state(&mis->state, MIGRATION_STATUS_ACTIVE, MIGRATION_STATUS_COLO); + failover_init_state(); + mis->to_src_file = qemu_file_get_return_path(mis->from_src_file); if (!mis->to_src_file) { error_report("COLO incoming thread: Open QEMUFile to_src_file failed"); diff --git a/migration/trace-events b/migration/trace-events index f374c8c..94134f7 100644 --- a/migration/trace-events +++ b/migration/trace-events @@ -212,3 +212,4 @@ migration_tls_incoming_handshake_complete(void) "" colo_vm_state_change(const char *old, const char *new) "Change '%s' => '%s'" colo_send_message(const char *msg) "Send '%s' message" colo_receive_message(const char *msg) "Receive '%s' message" +colo_failover_set_state(const char *new_state) "new state %s" diff --git a/qapi-schema.json b/qapi-schema.json index a184841..8a7b527 100644 --- a/qapi-schema.json +++ b/qapi-schema.json @@ -840,6 +840,24 @@ 'data': [ 'unknown', 'primary', 'secondary'] } ## +# @FailoverStatus +# +# An enumeration of COLO failover status +# +# @none: no failover has ever happened +# +# @require: got failover requirement but not handled +# +# @active: in the process of doing failover +# +# @completed: finish the process of failover +# +# Since: 2.8 +## +{ 'enum': 'FailoverStatus', + 'data': [ 'none', 'require', 'active', 'completed'] } + +## # @x-colo-lost-heartbeat # # Tell qemu that heartbeat is lost, request it to do takeover procedures. -- cgit v1.1