On 11/18/2010 10:07 AM, Arun R Bharadwaj wrote:
> Move qemu_paio_submit() to the new infrastructure and
> introduce the necessary APIs.
>
> Signed-off-by: Arun R Bharadwaj <a...@linux.vnet.ibm.com>
Looks good to me.
Acked-by: Venkateswararao Jujjuri <jv...@linux.vnet.ibm.com>
> ---
> posix-aio-compat.c | 224
> ++++++++++++++++++++++++++++++++++------------------
> 1 files changed, 147 insertions(+), 77 deletions(-)
>
> diff --git a/posix-aio-compat.c b/posix-aio-compat.c
> index eb1e2db..3f3c461 100644
> --- a/posix-aio-compat.c
> +++ b/posix-aio-compat.c
> @@ -31,6 +31,9 @@
>
> #include "block/raw-posix-aio.h"
>
> +#define MAX_GLOBAL_THREADS 64
> +#define MIN_GLOBAL_THREADS 8
> +
> static QemuMutex aiocb_mutex;
> static QemuCond aiocb_completion;
>
> @@ -52,6 +55,7 @@ typedef struct ThreadletWork
> } ThreadletWork;
>
> static ThreadletQueue globalqueue;
> +static int globalqueue_init;
>
> struct qemu_paiocb {
> BlockDriverAIOCB common;
> @@ -81,6 +85,100 @@ typedef struct PosixAioState {
> struct qemu_paiocb *first_aio;
> } PosixAioState;
>
> +static void *threadlet_worker(void *data)
> +{
> + ThreadletQueue *queue = data;
> +
> + qemu_mutex_lock(&queue->lock);
> + while (1) {
> + ThreadletWork *work;
> + int ret = 0;
> +
> + while (QTAILQ_EMPTY(&queue->request_list) &&
> + (ret != ETIMEDOUT)) {
> + /* wait for cond to be signalled or broadcast for 1000s */
> + ret = qemu_cond_timedwait((&queue->cond),
> + &(queue->lock), 10*100000);
> + }
> +
> + assert(queue->idle_threads != 0);
> + if (QTAILQ_EMPTY(&queue->request_list)) {
> + if (queue->cur_threads > queue->min_threads) {
> + /* We retain the minimum number of threads */
> + break;
> + }
> + } else {
> + work = QTAILQ_FIRST(&queue->request_list);
> + QTAILQ_REMOVE(&queue->request_list, work, node);
> +
> + queue->idle_threads--;
> + qemu_mutex_unlock(&queue->lock);
> +
> + /* execute the work function */
> + work->func(work);
> +
> + qemu_mutex_lock(&queue->lock);
> + queue->idle_threads++;
> + }
> + }
> +
> + queue->idle_threads--;
> + queue->cur_threads--;
> + qemu_mutex_unlock(&queue->lock);
> +
> + return NULL;
> +}
> +
> +static void spawn_threadlet(ThreadletQueue *queue)
> +{
> + QemuThread thread;
> +
> + queue->cur_threads++;
> + queue->idle_threads++;
> +
> + qemu_thread_create(&thread, threadlet_worker, queue);
> +}
> +
> +/**
> + * submit_work_to_queue: Submit a new task to a private queue to be
> + * executed asynchronously.
> + * @queue: Per-subsystem private queue to which the new task needs
> + * to be submitted.
> + * @work: Contains information about the task that needs to be submitted.
> + */
> +
> +static void submit_work_to_queue(ThreadletQueue *queue, ThreadletWork *work)
> +{
> + qemu_mutex_lock(&queue->lock);
> + if (queue->idle_threads == 0 && queue->cur_threads < queue->max_threads)
> {
> + spawn_threadlet(queue);
> + } else {
> + qemu_cond_signal(&queue->cond);
> + }
> + QTAILQ_INSERT_TAIL(&queue->request_list, work, node);
> + qemu_mutex_unlock(&queue->lock);
> +}
> +
> +static void threadlet_queue_init(ThreadletQueue *queue,
> + int max_threads, int min_threads);
> +
> +/**
> + * submit_work: Submit to the global queue a new task to be executed
> + * asynchronously.
> + * @work: Contains information about the task that needs to be submitted.
> + */
> +
> +static void submit_work(ThreadletWork *work)
> +{
> + if (!globalqueue_init) {
> + threadlet_queue_init(&globalqueue, MAX_GLOBAL_THREADS,
> + MIN_GLOBAL_THREADS);
> + globalqueue_init = 1;
> + }
> +
> + submit_work_to_queue(&globalqueue, work);
> +}
> +
> /**
> * dequeue_work_on_queue: Cancel a task queued on a Queue.
> * @queue: The queue containing the task to be cancelled.
> @@ -121,6 +219,25 @@ static int dequeue_work(ThreadletWork *work)
> return dequeue_work_on_queue(&globalqueue, work);
> }
>
> +/**
> + * threadlet_queue_init: Initialize a threadlet queue.
> + * @queue: The threadlet queue to be initialized.
> + * @max_threads: Maximum number of threads processing the queue.
> + * @min_threads: Minimum number of threads processing the queue.
> + */
> +
> +static void threadlet_queue_init(ThreadletQueue *queue,
> + int max_threads, int min_threads)
> +{
> + queue->cur_threads = 0;
> + queue->idle_threads = 0;
> + queue->max_threads = max_threads;
> + queue->min_threads = min_threads;
> + QTAILQ_INIT(&queue->request_list);
> + qemu_mutex_init(&queue->lock);
> + qemu_cond_init(&queue->cond);
> +}
> +
> static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
> static pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
> static pthread_t thread_id;
> @@ -363,96 +480,49 @@ static ssize_t handle_aiocb_rw(struct qemu_paiocb
> *aiocb)
> return nbytes;
> }
>
> -static void *aio_thread(void *unused)
> +static void aio_thread(ThreadletWork *work)
> {
> pid_t pid;
> + struct qemu_paiocb *aiocb = container_of(work, struct qemu_paiocb, work);
> + ssize_t ret = 0;
>
> pid = getpid();
>
> - while (1) {
> - struct qemu_paiocb *aiocb;
> - ssize_t ret = 0;
> - qemu_timeval tv;
> - struct timespec ts;
> -
> - qemu_gettimeofday(&tv);
> - ts.tv_sec = tv.tv_sec + 10;
> - ts.tv_nsec = 0;
> -
> - mutex_lock(&lock);
> -
> - while (QTAILQ_EMPTY(&request_list) &&
> - !(ret == ETIMEDOUT)) {
> - ret = cond_timedwait(&cond, &lock, &ts);
> - }
> -
> - if (QTAILQ_EMPTY(&request_list))
> - break;
> -
> - aiocb = QTAILQ_FIRST(&request_list);
> - QTAILQ_REMOVE(&request_list, aiocb, node);
> - aiocb->active = 1;
> - idle_threads--;
> - mutex_unlock(&lock);
> -
> - switch (aiocb->aio_type & QEMU_AIO_TYPE_MASK) {
> - case QEMU_AIO_READ:
> - case QEMU_AIO_WRITE:
> - ret = handle_aiocb_rw(aiocb);
> - break;
> - case QEMU_AIO_FLUSH:
> - ret = handle_aiocb_flush(aiocb);
> - break;
> - case QEMU_AIO_IOCTL:
> - ret = handle_aiocb_ioctl(aiocb);
> - break;
> - default:
> - fprintf(stderr, "invalid aio request (0x%x)\n", aiocb->aio_type);
> - ret = -EINVAL;
> - break;
> - }
> -
> - mutex_lock(&lock);
> - aiocb->ret = ret;
> - idle_threads++;
> - mutex_unlock(&lock);
> -
> - if (kill(pid, aiocb->ev_signo)) die("kill failed");
> + switch (aiocb->aio_type & QEMU_AIO_TYPE_MASK) {
> + case QEMU_AIO_READ:
> + case QEMU_AIO_WRITE:
> + ret = handle_aiocb_rw(aiocb);
> + break;
> + case QEMU_AIO_FLUSH:
> + ret = handle_aiocb_flush(aiocb);
> + break;
> + case QEMU_AIO_IOCTL:
> + ret = handle_aiocb_ioctl(aiocb);
> + break;
> + default:
> + fprintf(stderr, "invalid aio request (0x%x)\n", aiocb->aio_type);
> + ret = -EINVAL;
> + break;
> }
>
> - idle_threads--;
> - cur_threads--;
> - mutex_unlock(&lock);
> -
> - return NULL;
> -}
> -
> -static void spawn_thread(void)
> -{
> - sigset_t set, oldset;
> -
> - cur_threads++;
> - idle_threads++;
> -
> - /* block all signals */
> - if (sigfillset(&set)) die("sigfillset");
> - if (sigprocmask(SIG_SETMASK, &set, &oldset)) die("sigprocmask");
> -
> - thread_create(&thread_id, &attr, aio_thread, NULL);
> + qemu_mutex_lock(&aiocb_mutex);
> + aiocb->ret = ret;
> + qemu_cond_broadcast(&aiocb_completion);
> + qemu_mutex_unlock(&aiocb_mutex);
>
> - if (sigprocmask(SIG_SETMASK, &oldset, NULL)) die("sigprocmask restore");
> + if (kill(pid, aiocb->ev_signo)) {
> + die("kill failed");
> + }
> }
>
> static void qemu_paio_submit(struct qemu_paiocb *aiocb)
> {
> + qemu_mutex_lock(&aiocb_mutex);
> aiocb->ret = -EINPROGRESS;
> - aiocb->active = 0;
> - mutex_lock(&lock);
> - if (idle_threads == 0 && cur_threads < max_threads)
> - spawn_thread();
> - QTAILQ_INSERT_TAIL(&request_list, aiocb, node);
> - mutex_unlock(&lock);
> - cond_signal(&cond);
> + qemu_mutex_unlock(&aiocb_mutex);
> +
> + aiocb->work.func = aio_thread;
> + submit_work(&aiocb->work);
> }
>
> static ssize_t qemu_paio_return(struct qemu_paiocb *aiocb)
>
>
