Commit 973f2ddf authored by Max Reitz's avatar Max Reitz Committed by Kevin Wolf
Browse files

block/throttle-groups: Make incref/decref public 



Throttle groups are not necessarily referenced by BDSs alone; a later
patch will essentially allow BBs to reference them, too. Make the
ref/unref functions public so that reference can be properly accounted
for.

Their interface is slightly adjusted in that they return and take a
ThrottleState pointer, respectively, instead of a ThrottleGroup pointer.
Functionally, they are equivalent, but since ThrottleGroup is not meant
to be used outside of block/throttle-groups.c, ThrottleState is easier
to handle.

Signed-off-by: default avatarMax Reitz <mreitz@redhat.com>
Reviewed-by: default avatarKevin Wolf <kwolf@redhat.com>
Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
parent 373340b2

block/throttle-groups.c

+11 −8
Original line number Diff line number Diff line
@@ -76,9 +76,9 @@ static QTAILQ_HEAD(, ThrottleGroup) throttle_groups = 
 * created.

 *

 * @name: the name of the ThrottleGroup

 * @ret:  the ThrottleGroup

 * @ret:  the ThrottleState member of the ThrottleGroup

 */

static ThrottleGroup *throttle_group_incref(const char *name)

ThrottleState *throttle_group_incref(const char *name)

{

    ThrottleGroup *tg = NULL;

    ThrottleGroup *iter;
@@ -108,7 +108,7 @@ static ThrottleGroup *throttle_group_incref(const char *name) 


    qemu_mutex_unlock(&throttle_groups_lock);



    return tg;

    return &tg->ts;

}



/* Decrease the reference count of a ThrottleGroup.
@@ -116,10 +116,12 @@ static ThrottleGroup *throttle_group_incref(const char *name) 
 * When the reference count reaches zero the ThrottleGroup is

 * destroyed.

 *

 * @tg:  The ThrottleGroup to unref

 * @ts:  The ThrottleGroup to unref, given by its ThrottleState member

 */

static void throttle_group_unref(ThrottleGroup *tg)

void throttle_group_unref(ThrottleState *ts)

{

    ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts);



    qemu_mutex_lock(&throttle_groups_lock);

    if (--tg->refcount == 0) {

        QTAILQ_REMOVE(&throttle_groups, tg, list);
@@ -401,7 +403,8 @@ static void write_timer_cb(void *opaque) 
void throttle_group_register_bs(BlockDriverState *bs, const char *groupname)

{

    int i;

    ThrottleGroup *tg = throttle_group_incref(groupname);

    ThrottleState *ts = throttle_group_incref(groupname);

    ThrottleGroup *tg = container_of(ts, ThrottleGroup, ts);

    int clock_type = QEMU_CLOCK_REALTIME;



    if (qtest_enabled()) {
@@ -409,7 +412,7 @@ void throttle_group_register_bs(BlockDriverState *bs, const char *groupname) 
        clock_type = QEMU_CLOCK_VIRTUAL;

    }



    bs->throttle_state = &tg->ts;

    bs->throttle_state = ts;



    qemu_mutex_lock(&tg->lock);

    /* If the ThrottleGroup is new set this BlockDriverState as the token */
@@ -461,7 +464,7 @@ void throttle_group_unregister_bs(BlockDriverState *bs) 
    throttle_timers_destroy(&bs->throttle_timers);

    qemu_mutex_unlock(&tg->lock);



    throttle_group_unref(tg);

    throttle_group_unref(&tg->ts);

    bs->throttle_state = NULL;

}

include/block/throttle-groups.h

+3 −0
Original line number Diff line number Diff line
@@ -30,6 +30,9 @@ 


const char *throttle_group_get_name(BlockDriverState *bs);



ThrottleState *throttle_group_incref(const char *name);

void throttle_group_unref(ThrottleState *ts);



void throttle_group_config(BlockDriverState *bs, ThrottleConfig *cfg);

void throttle_group_get_config(BlockDriverState *bs, ThrottleConfig *cfg);