From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Subject: Re: [PATCH 05/16] Add io_uring IO interface Date: Tue, 15 Jan 2019 10:26:22 -0700 Message-ID: References: <20190115025531.13985-1-axboe@kernel.dk> <20190115025531.13985-6-axboe@kernel.dk> <20190115095134.6286b7d6@lwn.net> <5e1fe0b7-7998-d15d-267b-4dbbc01b0b53@kernel.dk> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <5e1fe0b7-7998-d15d-267b-4dbbc01b0b53@kernel.dk> Content-Language: en-US Sender: owner-linux-aio@kvack.org To: Jonathan Corbet Cc: linux-fsdevel@vger.kernel.org, linux-aio@kvack.org, linux-block@vger.kernel.org, linux-arch@vger.kernel.org, hch@lst.de, jmoyer@redhat.com, avi@scylladb.com List-Id: linux-arch.vger.kernel.org On 1/15/19 9:55 AM, Jens Axboe wrote: > On 1/15/19 9:51 AM, Jonathan Corbet wrote: >> On Mon, 14 Jan 2019 19:55:20 -0700 >> Jens Axboe wrote: >> >> So the [0/16] cover letter seems to have gone astray this time? > > It did go out, but I forgot to add a Subject line to it... > > https://marc.info/?l=linux-block&m=154752095709422&w=2 > > >>> The submission queue (SQ) and completion queue (CQ) rings are shared >>> between the application and the kernel. This eliminates the need to >>> copy data back and forth to submit and complete IO. >>> >>> IO submissions use the io_uring_sqe data structure, and completions >>> are generated in the form of io_uring_sqe data structures. The SQ >>> ring is an index into the io_uring_sqe array, which makes it possible >>> to submit a batch of IOs without them being contiguous in the ring. >>> The CQ ring is always contiguous, as completion events are inherently >>> unordered and can point to any io_uring_iocb. >>> >>> Two new system calls are added for this: >>> >>> io_uring_setup(entries, iovecs, params) >>> Sets up a context for doing async IO. On success, returns a file >>> descriptor that the application can mmap to gain access to the >>> SQ ring, CQ ring, and io_uring_iocbs. >> >> Looking at the code, it would appear that the "iovecs" parameter doesn't >> actually exist. > > Indeed, need to update that commit message. and io_uring_iocbs should > now be io_uring_sqes. > > The iovec/file registration is done through io_uring_register(2). Updated commit message which covers both this one, and the IORING_ENTER_GETEVENTS below. http://git.kernel.dk/cgit/linux-block/commit/?h=io_uring&id=d14a06629baef2b0701dbd01ac9c9066f73065ec -- Jens Axboe -- To unsubscribe, send a message with 'unsubscribe linux-aio' in the body to majordomo@kvack.org. For more info on Linux AIO, see: http://www.kvack.org/aio/ Don't email: aart@kvack.org From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf1-f193.google.com ([209.85.210.193]:38458 "EHLO mail-pf1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388277AbfAOR02 (ORCPT ); Tue, 15 Jan 2019 12:26:28 -0500 Received: by mail-pf1-f193.google.com with SMTP id q1so1626807pfi.5 for ; Tue, 15 Jan 2019 09:26:27 -0800 (PST) Subject: Re: [PATCH 05/16] Add io_uring IO interface From: Jens Axboe References: <20190115025531.13985-1-axboe@kernel.dk> <20190115025531.13985-6-axboe@kernel.dk> <20190115095134.6286b7d6@lwn.net> <5e1fe0b7-7998-d15d-267b-4dbbc01b0b53@kernel.dk> Message-ID: Date: Tue, 15 Jan 2019 10:26:22 -0700 MIME-Version: 1.0 In-Reply-To: <5e1fe0b7-7998-d15d-267b-4dbbc01b0b53@kernel.dk> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-arch-owner@vger.kernel.org List-ID: To: Jonathan Corbet Cc: linux-fsdevel@vger.kernel.org, linux-aio@kvack.org, linux-block@vger.kernel.org, linux-arch@vger.kernel.org, hch@lst.de, jmoyer@redhat.com, avi@scylladb.com Message-ID: <20190115172622.RRYbPDDA4YAdVe0ZsbFgcw8kCAufGPC3wiQBwge0Yh0@z> On 1/15/19 9:55 AM, Jens Axboe wrote: > On 1/15/19 9:51 AM, Jonathan Corbet wrote: >> On Mon, 14 Jan 2019 19:55:20 -0700 >> Jens Axboe wrote: >> >> So the [0/16] cover letter seems to have gone astray this time? > > It did go out, but I forgot to add a Subject line to it... > > https://marc.info/?l=linux-block&m=154752095709422&w=2 > > >>> The submission queue (SQ) and completion queue (CQ) rings are shared >>> between the application and the kernel. This eliminates the need to >>> copy data back and forth to submit and complete IO. >>> >>> IO submissions use the io_uring_sqe data structure, and completions >>> are generated in the form of io_uring_sqe data structures. The SQ >>> ring is an index into the io_uring_sqe array, which makes it possible >>> to submit a batch of IOs without them being contiguous in the ring. >>> The CQ ring is always contiguous, as completion events are inherently >>> unordered and can point to any io_uring_iocb. >>> >>> Two new system calls are added for this: >>> >>> io_uring_setup(entries, iovecs, params) >>> Sets up a context for doing async IO. On success, returns a file >>> descriptor that the application can mmap to gain access to the >>> SQ ring, CQ ring, and io_uring_iocbs. >> >> Looking at the code, it would appear that the "iovecs" parameter doesn't >> actually exist. > > Indeed, need to update that commit message. and io_uring_iocbs should > now be io_uring_sqes. > > The iovec/file registration is done through io_uring_register(2). Updated commit message which covers both this one, and the IORING_ENTER_GETEVENTS below. http://git.kernel.dk/cgit/linux-block/commit/?h=io_uring&id=d14a06629baef2b0701dbd01ac9c9066f73065ec -- Jens Axboe