diff options
| -rw-r--r-- | fs/aio.c | 86 | ||||
| -rw-r--r-- | include/linux/aio.h | 4 |
2 files changed, 36 insertions, 54 deletions
@@ -89,7 +89,7 @@ struct kioctx { spinlock_t ctx_lock; - int reqs_active; + atomic_t reqs_active; struct list_head active_reqs; /* used for cancellation */ /* sys_io_setup currently limits this to an unsigned int */ @@ -250,7 +250,7 @@ static void ctx_rcu_free(struct rcu_head *head) static void __put_ioctx(struct kioctx *ctx) { unsigned nr_events = ctx->max_reqs; - BUG_ON(ctx->reqs_active); + BUG_ON(atomic_read(&ctx->reqs_active)); aio_free_ring(ctx); if (nr_events) { @@ -284,7 +284,7 @@ static int kiocb_cancel(struct kioctx *ctx, struct kiocb *kiocb, cancel = kiocb->ki_cancel; kiocbSetCancelled(kiocb); if (cancel) { - kiocb->ki_users++; + atomic_inc(&kiocb->ki_users); spin_unlock_irq(&ctx->ctx_lock); memset(res, 0, sizeof(*res)); @@ -383,12 +383,12 @@ static void kill_ctx(struct kioctx *ctx) kiocb_cancel(ctx, req, &res); } - if (!ctx->reqs_active) + if (!atomic_read(&ctx->reqs_active)) goto out; add_wait_queue(&ctx->wait, &wait); set_task_state(tsk, TASK_UNINTERRUPTIBLE); - while (ctx->reqs_active) { + while (atomic_read(&ctx->reqs_active)) { spin_unlock_irq(&ctx->ctx_lock); io_schedule(); set_task_state(tsk, TASK_UNINTERRUPTIBLE); @@ -406,9 +406,9 @@ out: */ ssize_t wait_on_sync_kiocb(struct kiocb *iocb) { - while (iocb->ki_users) { + while (atomic_read(&iocb->ki_users)) { set_current_state(TASK_UNINTERRUPTIBLE); - if (!iocb->ki_users) + if (!atomic_read(&iocb->ki_users)) break; io_schedule(); } @@ -438,7 +438,7 @@ void exit_aio(struct mm_struct *mm) printk(KERN_DEBUG "exit_aio:ioctx still alive: %d %d %d\n", atomic_read(&ctx->users), ctx->dead, - ctx->reqs_active); + atomic_read(&ctx->reqs_active)); /* * We don't need to bother with munmap() here - * exit_mmap(mm) is coming and it'll unmap everything. @@ -453,11 +453,11 @@ void exit_aio(struct mm_struct *mm) } /* aio_get_req - * Allocate a slot for an aio request. Increments the users count + * Allocate a slot for an aio request. Increments the ki_users count * of the kioctx so that the kioctx stays around until all requests are * complete. Returns NULL if no requests are free. * - * Returns with kiocb->users set to 2. The io submit code path holds + * Returns with kiocb->ki_users set to 2. The io submit code path holds * an extra reference while submitting the i/o. * This prevents races between the aio code path referencing the * req (after submitting it) and aio_complete() freeing the req. @@ -471,7 +471,7 @@ static struct kiocb *__aio_get_req(struct kioctx *ctx) return NULL; req->ki_flags = 0; - req->ki_users = 2; + atomic_set(&req->ki_users, 2); req->ki_key = 0; req->ki_ctx = ctx; req->ki_cancel = NULL; @@ -512,9 +512,9 @@ static void kiocb_batch_free(struct kioctx *ctx, struct kiocb_batch *batch) list_del(&req->ki_batch); list_del(&req->ki_list); kmem_cache_free(kiocb_cachep, req); - ctx->reqs_active--; + atomic_dec(&ctx->reqs_active); } - if (unlikely(!ctx->reqs_active && ctx->dead)) + if (unlikely(!atomic_read(&ctx->reqs_active) && ctx->dead)) wake_up_all(&ctx->wait); spin_unlock_irq(&ctx->ctx_lock); } @@ -545,7 +545,8 @@ static int kiocb_batch_refill(struct kioctx *ctx, struct kiocb_batch *batch) spin_lock_irq(&ctx->ctx_lock); ring = kmap_atomic(ctx->ring_info.ring_pages[0]); - avail = aio_ring_avail(&ctx->ring_info, ring) - ctx->reqs_active; + avail = aio_ring_avail(&ctx->ring_info, ring) - + atomic_read(&ctx->reqs_active); BUG_ON(avail < 0); if (avail < allocated) { /* Trim back the number of requests. */ @@ -560,7 +561,7 @@ static int kiocb_batch_refill(struct kioctx *ctx, struct kiocb_batch *batch) batch->count -= allocated; list_for_each_entry(req, &batch->head, ki_batch) { list_add(&req->ki_list, &ctx->active_reqs); - ctx->reqs_active++; + atomic_inc(&ctx->reqs_active); } kunmap_atomic(ring); @@ -583,10 +584,8 @@ static inline struct kiocb *aio_get_req(struct kioctx *ctx, return req; } -static inline void really_put_req(struct kioctx *ctx, struct kiocb *req) +static void kiocb_free(struct kiocb *req) { - assert_spin_locked(&ctx->ctx_lock); - if (req->ki_filp) fput(req->ki_filp); if (req->ki_eventfd != NULL) @@ -596,40 +595,12 @@ static inline void really_put_req(struct kioctx *ctx, struct kiocb *req) if (req->ki_iovec != &req->ki_inline_vec) kfree(req->ki_iovec); kmem_cache_free(kiocb_cachep, req); - ctx->reqs_active--; - - if (unlikely(!ctx->reqs_active && ctx->dead)) - wake_up_all(&ctx->wait); } -/* __aio_put_req - * Returns true if this put was the last user of the request. - */ -static void __aio_put_req(struct kioctx *ctx, struct kiocb *req) -{ - assert_spin_locked(&ctx->ctx_lock); - - req->ki_users--; - BUG_ON(req->ki_users < 0); - if (likely(req->ki_users)) - return; - list_del(&req->ki_list); /* remove from active_reqs */ - req->ki_cancel = NULL; - req->ki_retry = NULL; - - really_put_req(ctx, req); -} - -/* aio_put_req - * Returns true if this put was the last user of the kiocb, - * false if the request is still in use. - */ void aio_put_req(struct kiocb *req) { - struct kioctx *ctx = req->ki_ctx; - spin_lock_irq(&ctx->ctx_lock); - __aio_put_req(ctx, req); - spin_unlock_irq(&ctx->ctx_lock); + if (atomic_dec_and_test(&req->ki_users)) + kiocb_free(req); } EXPORT_SYMBOL(aio_put_req); @@ -677,9 +648,9 @@ void aio_complete(struct kiocb *iocb, long res, long res2) * - the sync task helpfully left a reference to itself in the iocb */ if (is_sync_kiocb(iocb)) { - BUG_ON(iocb->ki_users != 1); + BUG_ON(atomic_read(&iocb->ki_users) != 1); iocb->ki_user_data = res; - iocb->ki_users = 0; + atomic_set(&iocb->ki_users, 0); wake_up_process(iocb->ki_obj.tsk); return; } @@ -694,6 +665,8 @@ void aio_complete(struct kiocb *iocb, long res, long res2) */ spin_lock_irqsave(&ctx->ctx_lock, flags); + list_del(&iocb->ki_list); /* remove from active_reqs */ + /* * cancelled requests don't get events, userland was given one * when the event got cancelled. @@ -740,7 +713,8 @@ void aio_complete(struct kiocb *iocb, long res, long res2) put_rq: /* everything turned out well, dispose of the aiocb. */ - __aio_put_req(ctx, iocb); + aio_put_req(iocb); + atomic_dec(&ctx->reqs_active); /* * We have to order our ring_info tail store above and test @@ -905,7 +879,7 @@ static int read_events(struct kioctx *ctx, break; /* Try to only show up in io wait if there are ops * in flight */ - if (ctx->reqs_active) + if (atomic_read(&ctx->reqs_active)) io_schedule(); else schedule(); @@ -1369,6 +1343,14 @@ static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb, return 0; out_put_req: + spin_lock_irq(&ctx->ctx_lock); + list_del(&req->ki_list); + spin_unlock_irq(&ctx->ctx_lock); + + atomic_dec(&ctx->reqs_active); + if (unlikely(!atomic_read(&ctx->reqs_active) && ctx->dead)) + wake_up_all(&ctx->wait); + aio_put_req(req); /* drop extra ref to req */ aio_put_req(req); /* drop i/o ref to req */ return ret; diff --git a/include/linux/aio.h b/include/linux/aio.h index 7b1eb234e0ab..1e728f0086f8 100644 --- a/include/linux/aio.h +++ b/include/linux/aio.h @@ -49,7 +49,7 @@ struct kioctx; */ struct kiocb { unsigned long ki_flags; - int ki_users; + atomic_t ki_users; unsigned ki_key; /* id of this request */ struct file *ki_filp; @@ -96,7 +96,7 @@ static inline bool is_sync_kiocb(struct kiocb *kiocb) static inline void init_sync_kiocb(struct kiocb *kiocb, struct file *filp) { *kiocb = (struct kiocb) { - .ki_users = 1, + .ki_users = ATOMIC_INIT(1), .ki_key = KIOCB_SYNC_KEY, .ki_filp = filp, .ki_obj.tsk = current, |