Commit 7d9c8581 authored by Paolo Bonzini's avatar Paolo Bonzini Committed by Kevin Wolf
Browse files

coroutine: use QSIMPLEQ instead of QTAILQ 



CoQueue do not need to remove any element but the head of the list;
processing is always strictly FIFO.  Therefore, the simpler singly-linked
QSIMPLEQ can be used instead.

Reviewed-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: default avatarFam Zheng <famz@redhat.com>
Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
parent 5af7045b

include/qemu/coroutine.h

+1 −1
Original line number Diff line number Diff line
@@ -102,7 +102,7 @@ bool qemu_in_coroutine(void); 
 * are built.

 */

typedef struct CoQueue {

    QTAILQ_HEAD(, Coroutine) entries;

    QSIMPLEQ_HEAD(, Coroutine) entries;

} CoQueue;



/**

include/qemu/coroutine_int.h

+2 −2
Original line number Diff line number Diff line
@@ -41,8 +41,8 @@ struct Coroutine { 
    QSLIST_ENTRY(Coroutine) pool_next;



    /* Coroutines that should be woken up when we yield or terminate */

    QTAILQ_HEAD(, Coroutine) co_queue_wakeup;

    QTAILQ_ENTRY(Coroutine) co_queue_next;

    QSIMPLEQ_HEAD(, Coroutine) co_queue_wakeup;

    QSIMPLEQ_ENTRY(Coroutine) co_queue_next;

};



Coroutine *qemu_coroutine_new(void);

util/qemu-coroutine-lock.c

+11 −11
Original line number Diff line number Diff line
@@ -31,13 +31,13 @@ 


void qemu_co_queue_init(CoQueue *queue)

{

    QTAILQ_INIT(&queue->entries);

    QSIMPLEQ_INIT(&queue->entries);

}



void coroutine_fn qemu_co_queue_wait(CoQueue *queue)

{

    Coroutine *self = qemu_coroutine_self();

    QTAILQ_INSERT_TAIL(&queue->entries, self, co_queue_next);

    QSIMPLEQ_INSERT_TAIL(&queue->entries, self, co_queue_next);

    qemu_coroutine_yield();

    assert(qemu_in_coroutine());

}
@@ -55,8 +55,8 @@ void qemu_co_queue_run_restart(Coroutine *co) 
    Coroutine *next;



    trace_qemu_co_queue_run_restart(co);

    while ((next = QTAILQ_FIRST(&co->co_queue_wakeup))) {

        QTAILQ_REMOVE(&co->co_queue_wakeup, next, co_queue_next);

    while ((next = QSIMPLEQ_FIRST(&co->co_queue_wakeup))) {

        QSIMPLEQ_REMOVE_HEAD(&co->co_queue_wakeup, co_queue_next);

        qemu_coroutine_enter(next, NULL);

    }

}
@@ -66,13 +66,13 @@ static bool qemu_co_queue_do_restart(CoQueue *queue, bool single) 
    Coroutine *self = qemu_coroutine_self();

    Coroutine *next;



    if (QTAILQ_EMPTY(&queue->entries)) {

    if (QSIMPLEQ_EMPTY(&queue->entries)) {

        return false;

    }



    while ((next = QTAILQ_FIRST(&queue->entries)) != NULL) {

        QTAILQ_REMOVE(&queue->entries, next, co_queue_next);

        QTAILQ_INSERT_TAIL(&self->co_queue_wakeup, next, co_queue_next);

    while ((next = QSIMPLEQ_FIRST(&queue->entries)) != NULL) {

        QSIMPLEQ_REMOVE_HEAD(&queue->entries, co_queue_next);

        QSIMPLEQ_INSERT_TAIL(&self->co_queue_wakeup, next, co_queue_next);

        trace_qemu_co_queue_next(next);

        if (single) {

            break;
@@ -97,19 +97,19 @@ bool qemu_co_enter_next(CoQueue *queue) 
{

    Coroutine *next;



    next = QTAILQ_FIRST(&queue->entries);

    next = QSIMPLEQ_FIRST(&queue->entries);

    if (!next) {

        return false;

    }



    QTAILQ_REMOVE(&queue->entries, next, co_queue_next);

    QSIMPLEQ_REMOVE_HEAD(&queue->entries, co_queue_next);

    qemu_coroutine_enter(next, NULL);

    return true;

}



bool qemu_co_queue_empty(CoQueue *queue)

{

    return QTAILQ_FIRST(&queue->entries) == NULL;

    return QSIMPLEQ_FIRST(&queue->entries) == NULL;

}



void qemu_co_mutex_init(CoMutex *mutex)

util/qemu-coroutine.c

+1 −1
Original line number Diff line number Diff line
@@ -76,7 +76,7 @@ Coroutine *qemu_coroutine_create(CoroutineEntry *entry) 
    }



    co->entry = entry;

    QTAILQ_INIT(&co->co_queue_wakeup);

    QSIMPLEQ_INIT(&co->co_queue_wakeup);

    return co;

}