Commit ebac1202 authored by Paolo Bonzini's avatar Paolo Bonzini Committed by Greg Kurz
Browse files

virtio-9p: use QEMU thread pool 



The QEMU thread pool already has a mechanism to invoke callbacks in the main
thread.  It does not need an EventNotifier and it is more efficient too.
Use it instead of GAsyncQueue + GThreadPool + glue.

As a side effect, it silences Coverity's complaint about an unchecked
return value for event_notifier_init.

Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: default avatarGreg Kurz <gkurz@linux.vnet.ibm.com>
(removed no more needed #include <glib.h> from virtio-9p-coth.h)
Signed-off-by: default avatarGreg Kurz <gkurz@linux.vnet.ibm.com>
parent 49f817ca

hw/9pfs/virtio-9p-coth.c

+14 −55
Original line number Diff line number Diff line
@@ -12,71 +12,30 @@ 
 *

 */



#include "fsdev/qemu-fsdev.h"

#include "qemu/thread.h"

#include "qemu/event_notifier.h"

#include "qemu-common.h"

#include "block/thread-pool.h"

#include "qemu/coroutine.h"

#include "qemu/main-loop.h"

#include "virtio-9p-coth.h"



/* v9fs glib thread pool */

static V9fsThPool v9fs_pool;



void co_run_in_worker_bh(void *opaque)

/* Called from QEMU I/O thread.  */

static void coroutine_enter_cb(void *opaque, int ret)

{

    Coroutine *co = opaque;

    g_thread_pool_push(v9fs_pool.pool, co, NULL);

}



static void v9fs_qemu_process_req_done(EventNotifier *e)

{

    Coroutine *co;



    event_notifier_test_and_clear(e);



    while ((co = g_async_queue_try_pop(v9fs_pool.completed)) != NULL) {

    qemu_coroutine_enter(co, NULL);

}

}



static void v9fs_thread_routine(gpointer data, gpointer user_data)

/* Called from worker thread.  */

static int coroutine_enter_func(void *arg)

{

    Coroutine *co = data;



    Coroutine *co = arg;

    qemu_coroutine_enter(co, NULL);



    g_async_queue_push(v9fs_pool.completed, co);



    event_notifier_set(&v9fs_pool.e);

    return 0;

}



int v9fs_init_worker_threads(void)

void co_run_in_worker_bh(void *opaque)

{

    int ret = 0;

    V9fsThPool *p = &v9fs_pool;

    sigset_t set, oldset;



    sigfillset(&set);

    /* Leave signal handling to the iothread.  */

    pthread_sigmask(SIG_SETMASK, &set, &oldset);



    p->pool = g_thread_pool_new(v9fs_thread_routine, p, -1, FALSE, NULL);

    if (!p->pool) {

        ret = -1;

        goto err_out;

    }

    p->completed = g_async_queue_new();

    if (!p->completed) {

        /*

         * We are going to terminate.

         * So don't worry about cleanup

         */

        ret = -1;

        goto err_out;

    }

    event_notifier_init(&p->e, 0);



    event_notifier_set_handler(&p->e, v9fs_qemu_process_req_done);

err_out:

    pthread_sigmask(SIG_SETMASK, &oldset, NULL);

    return ret;

    Coroutine *co = opaque;

    thread_pool_submit_aio(qemu_get_aio_context()->thread_pool,

                           coroutine_enter_func, co, coroutine_enter_cb, co);

}

hw/9pfs/virtio-9p-coth.h

+1 −9
Original line number Diff line number Diff line
@@ -18,14 +18,6 @@ 
#include "qemu/thread.h"

#include "qemu/coroutine.h"

#include "virtio-9p.h"

#include <glib.h>



typedef struct V9fsThPool {

    EventNotifier e;



    GThreadPool *pool;

    GAsyncQueue *completed;

} V9fsThPool;



/*

 * we want to use bottom half because we want to make sure the below
@@ -45,7 +37,7 @@ typedef struct V9fsThPool { 
        qemu_bh_schedule(co_bh);                                        \

        /*                                                              \

         * yield in qemu thread and re-enter back                       \

         * in glib worker thread                                        \

         * in worker thread                                             \

         */                                                             \

        qemu_coroutine_yield();                                         \

        qemu_bh_delete(co_bh);                                          \

hw/9pfs/virtio-9p-device.c

+0 −4
Original line number Diff line number Diff line
@@ -116,10 +116,6 @@ static void virtio_9p_device_realize(DeviceState *dev, Error **errp) 
                   " and export path:%s", s->fsconf.fsdev_id, s->ctx.fs_root);

        goto out;

    }

    if (v9fs_init_worker_threads() < 0) {

        error_setg(errp, "worker thread initialization failed");

        goto out;

    }



    /*

     * Check details of export path, We need to use fs driver