From d538ea4cb8e7241af8091eee30483fabf64444a5 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 26 Nov 2021 12:58:15 +0100 Subject: [PATCH] block: return the io_context from create_task_io_context Grab a reference to the newly allocated or existing io_context in create_task_io_context and return it. This simplifies the callers and removes the need for double lookups. Signed-off-by: Christoph Hellwig Link: https://lore.kernel.org/r/20211126115817.2087431-13-hch@lst.de Signed-off-by: Jens Axboe --- block/blk-ioc.c | 66 ++++++++++++++++++++++--------------------------- 1 file changed, 30 insertions(+), 36 deletions(-) diff --git a/block/blk-ioc.c b/block/blk-ioc.c index f06d1040442c..5bfe810496fc 100644 --- a/block/blk-ioc.c +++ b/block/blk-ioc.c @@ -268,15 +268,14 @@ static struct io_context *alloc_io_context(gfp_t gfp_flags, int node) return ioc; } -static int create_task_io_context(struct task_struct *task, gfp_t gfp_flags, - int node) +static struct io_context *create_task_io_context(struct task_struct *task, + gfp_t gfp_flags, int node) { struct io_context *ioc; - int ret; ioc = alloc_io_context(gfp_flags, node); if (!ioc) - return -ENOMEM; + return NULL; /* * Try to install. ioc shouldn't be installed if someone else @@ -292,11 +291,11 @@ static int create_task_io_context(struct task_struct *task, gfp_t gfp_flags, else kmem_cache_free(iocontext_cachep, ioc); - ret = task->io_context ? 0 : -EBUSY; - + ioc = task->io_context; + if (ioc) + get_io_context(ioc); task_unlock(task); - - return ret; + return ioc; } /** @@ -319,18 +318,15 @@ struct io_context *get_task_io_context(struct task_struct *task, might_sleep_if(gfpflags_allow_blocking(gfp_flags)); - do { - task_lock(task); - ioc = task->io_context; - if (likely(ioc)) { - get_io_context(ioc); - task_unlock(task); - return ioc; - } + task_lock(task); + ioc = task->io_context; + if (unlikely(!ioc)) { task_unlock(task); - } while (!create_task_io_context(task, gfp_flags, node)); - - return NULL; + return create_task_io_context(task, gfp_flags, node); + } + get_io_context(ioc); + task_unlock(task); + return ioc; } int __copy_io(unsigned long clone_flags, struct task_struct *tsk) @@ -449,30 +445,28 @@ static struct io_cq *ioc_create_icq(struct io_context *ioc, struct io_cq *ioc_find_get_icq(struct request_queue *q) { - struct io_context *ioc; - struct io_cq *icq; + struct io_context *ioc = current->io_context; + struct io_cq *icq = NULL; - /* create task io_context, if we don't have one already */ - if (unlikely(!current->io_context)) - create_task_io_context(current, GFP_ATOMIC, q->node); + if (unlikely(!ioc)) { + ioc = create_task_io_context(current, GFP_ATOMIC, q->node); + if (!ioc) + return NULL; + } else { + get_io_context(ioc); - /* - * May not have an IO context if it's a passthrough request - */ - ioc = current->io_context; - if (!ioc) - return NULL; - - spin_lock_irq(&q->queue_lock); - icq = ioc_lookup_icq(ioc, q); - spin_unlock_irq(&q->queue_lock); + spin_lock_irq(&q->queue_lock); + icq = ioc_lookup_icq(ioc, q); + spin_unlock_irq(&q->queue_lock); + } if (!icq) { icq = ioc_create_icq(ioc, q, GFP_ATOMIC); - if (!icq) + if (!icq) { + put_io_context(ioc); return NULL; + } } - get_io_context(icq->ioc); return icq; } EXPORT_SYMBOL_GPL(ioc_find_get_icq);