This patch adds a notifier chain for the memory precopy. This enables various precopy optimizations to be invoked at specific places.
Signed-off-by: Wei Wang <wei.w.w...@intel.com> CC: Dr. David Alan Gilbert <dgilb...@redhat.com> CC: Juan Quintela <quint...@redhat.com> CC: Michael S. Tsirkin <m...@redhat.com> CC: Peter Xu <pet...@redhat.com> Reviewed-by: Peter Xu <pet...@redhat.com> --- include/migration/misc.h | 19 ++++++++++++++++++ migration/ram.c | 51 +++++++++++++++++++++++++++++++++++++++++++++--- migration/savevm.c | 15 ++++++++++++++ vl.c | 1 + 4 files changed, 83 insertions(+), 3 deletions(-) diff --git a/include/migration/misc.h b/include/migration/misc.h index 113320e..15f8d00 100644 --- a/include/migration/misc.h +++ b/include/migration/misc.h @@ -19,6 +19,25 @@ /* migration/ram.c */ +typedef enum PrecopyNotifyReason { + PRECOPY_NOTIFY_SETUP = 0, + PRECOPY_NOTIFY_BEFORE_BITMAP_SYNC = 1, + PRECOPY_NOTIFY_AFTER_BITMAP_SYNC = 2, + PRECOPY_NOTIFY_COMPLETE = 3, + PRECOPY_NOTIFY_CLEANUP = 4, + PRECOPY_NOTIFY_MAX = 5, +} PrecopyNotifyReason; + +typedef struct PrecopyNotifyData { + enum PrecopyNotifyReason reason; + Error **errp; +} PrecopyNotifyData; + +void precopy_infrastructure_init(void); +void precopy_add_notifier(NotifierWithReturn *n); +void precopy_remove_notifier(NotifierWithReturn *n); +int precopy_notify(PrecopyNotifyReason reason, Error **errp); + void ram_mig_init(void); void qemu_guest_free_page_hint(void *addr, size_t len); diff --git a/migration/ram.c b/migration/ram.c index c13b44f..1e00d92 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -328,6 +328,32 @@ typedef struct RAMState RAMState; static RAMState *ram_state; +static NotifierWithReturnList precopy_notifier_list; + +void precopy_infrastructure_init(void) +{ + notifier_with_return_list_init(&precopy_notifier_list); +} + +void precopy_add_notifier(NotifierWithReturn *n) +{ + notifier_with_return_list_add(&precopy_notifier_list, n); +} + +void precopy_remove_notifier(NotifierWithReturn *n) +{ + notifier_with_return_remove(n); +} + +int precopy_notify(PrecopyNotifyReason reason, Error **errp) +{ + PrecopyNotifyData pnd; + pnd.reason = reason; + pnd.errp = errp; + + return notifier_with_return_list_notify(&precopy_notifier_list, &pnd); +} + uint64_t ram_bytes_remaining(void) { return ram_state ? (ram_state->migration_dirty_pages * TARGET_PAGE_SIZE) : @@ -1701,6 +1727,25 @@ static void migration_bitmap_sync(RAMState *rs) } } +static void migration_bitmap_sync_precopy(RAMState *rs) +{ + Error *local_err = NULL; + + /* + * The current notifier usage is just an optimization to migration, so we + * don't stop the normal migration process in the error case. + */ + if (precopy_notify(PRECOPY_NOTIFY_BEFORE_BITMAP_SYNC, &local_err)) { + error_report_err(local_err); + } + + migration_bitmap_sync(rs); + + if (precopy_notify(PRECOPY_NOTIFY_AFTER_BITMAP_SYNC, &local_err)) { + error_report_err(local_err); + } +} + /** * save_zero_page_to_file: send the zero page to the file * @@ -3072,7 +3117,7 @@ static void ram_init_bitmaps(RAMState *rs) ram_list_init_bitmaps(); memory_global_dirty_log_start(); - migration_bitmap_sync(rs); + migration_bitmap_sync_precopy(rs); rcu_read_unlock(); qemu_mutex_unlock_ramlist(); @@ -3348,7 +3393,7 @@ static int ram_save_complete(QEMUFile *f, void *opaque) rcu_read_lock(); if (!migration_in_postcopy()) { - migration_bitmap_sync(rs); + migration_bitmap_sync_precopy(rs); } ram_control_before_iterate(f, RAM_CONTROL_FINISH); @@ -3397,7 +3442,7 @@ static void ram_save_pending(QEMUFile *f, void *opaque, uint64_t max_size, remaining_size < max_size) { qemu_mutex_lock_iothread(); rcu_read_lock(); - migration_bitmap_sync(rs); + migration_bitmap_sync_precopy(rs); rcu_read_unlock(); qemu_mutex_unlock_iothread(); remaining_size = rs->migration_dirty_pages * TARGET_PAGE_SIZE; diff --git a/migration/savevm.c b/migration/savevm.c index 9e45fb4..ec74f44 100644 --- a/migration/savevm.c +++ b/migration/savevm.c @@ -1018,6 +1018,7 @@ void qemu_savevm_state_header(QEMUFile *f) void qemu_savevm_state_setup(QEMUFile *f) { SaveStateEntry *se; + Error *local_err = NULL; int ret; trace_savevm_state_setup(); @@ -1039,6 +1040,10 @@ void qemu_savevm_state_setup(QEMUFile *f) break; } } + + if (precopy_notify(PRECOPY_NOTIFY_SETUP, &local_err)) { + error_report_err(local_err); + } } int qemu_savevm_state_resume_prepare(MigrationState *s) @@ -1181,6 +1186,11 @@ int qemu_savevm_state_complete_precopy(QEMUFile *f, bool iterable_only, SaveStateEntry *se; int ret; bool in_postcopy = migration_in_postcopy(); + Error *local_err = NULL; + + if (precopy_notify(PRECOPY_NOTIFY_COMPLETE, &local_err)) { + error_report_err(local_err); + } trace_savevm_state_complete_precopy(); @@ -1313,6 +1323,11 @@ void qemu_savevm_state_pending(QEMUFile *f, uint64_t threshold_size, void qemu_savevm_state_cleanup(void) { SaveStateEntry *se; + Error *local_err = NULL; + + if (precopy_notify(PRECOPY_NOTIFY_CLEANUP, &local_err)) { + error_report_err(local_err); + } trace_savevm_state_cleanup(); QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { diff --git a/vl.c b/vl.c index a5ae5f2..1621e1c 100644 --- a/vl.c +++ b/vl.c @@ -3062,6 +3062,7 @@ int main(int argc, char **argv, char **envp) module_call_init(MODULE_INIT_OPTS); runstate_init(); + precopy_infrastructure_init(); postcopy_infrastructure_init(); monitor_init_globals(); -- 1.8.3.1