Commit bd227060 authored by Wei Wang's avatar Wei Wang Committed by Dr. David Alan Gilbert
Browse files

migration/ram.c: add a notifier chain for precopy 



This patch adds a notifier chain for the memory precopy. This enables various
precopy optimizations to be invoked at specific places.

Signed-off-by: default avatarWei Wang <wei.w.wang@intel.com>
CC: Dr. David Alan Gilbert <dgilbert@redhat.com>
CC: Juan Quintela <quintela@redhat.com>
CC: Michael S. Tsirkin <mst@redhat.com>
CC: Peter Xu <peterx@redhat.com>
Reviewed-by: default avatarPeter Xu <peterx@redhat.com>
Message-Id: <1544516693-5395-6-git-send-email-wei.w.wang@intel.com>
Signed-off-by: default avatarDr. David Alan Gilbert <dgilbert@redhat.com>
parent 6bcb05fc

include/migration/misc.h

+19 −0
Original line number Diff line number Diff line
@@ -20,6 +20,25 @@ 


/* 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);

migration/ram.c

+48 −3
Original line number Diff line number Diff line
@@ -354,6 +354,32 @@ 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) :
@@ -1741,6 +1767,25 @@ 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

 *
@@ -3123,7 +3168,7 @@ 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();
@@ -3403,7 +3448,7 @@ 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);
@@ -3452,7 +3497,7 @@ 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;

migration/savevm.c

+15 −0
Original line number Diff line number Diff line
@@ -1088,6 +1088,7 @@ 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();
@@ -1109,6 +1110,10 @@ 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)
@@ -1251,6 +1256,11 @@ 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();
@@ -1383,6 +1393,11 @@ 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) {

vl.c

+1 −0
Original line number Diff line number Diff line
@@ -3039,6 +3039,7 @@ 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();