From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx3-rdu2.redhat.com ([66.187.233.73]:51744 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751176AbeEUU6l (ORCPT ); Mon, 21 May 2018 16:58:41 -0400 From: Jeff Moyer To: adam.manzanares@wdc.com Cc: viro@zeniv.linux.org.uk, linux-fsdevel@vger.kernel.org, axboe@kernel.dk, bcrl@kvack.org, tglx@linutronix.de, mingo@kernel.org, pombredanne@nexb.com, kstewart@linuxfoundation.org, gregkh@linuxfoundation.org, bigeasy@linutronix.de, jack@suse.cz, darrick.wong@oracle.com, rgoldwyn@suse.com, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-aio@kvack.org, linux-api@vger.kernel.org, hch@infradead.org Subject: Re: [PATCH v5 3/5] fs: Add aio iopriority support References: <20180521160147.2372-1-adam.manzanares@wdc.com> <20180521160147.2372-4-adam.manzanares@wdc.com> Date: Mon, 21 May 2018 16:58:39 -0400 In-Reply-To: <20180521160147.2372-4-adam.manzanares@wdc.com> (adam manzanares's message of "Mon, 21 May 2018 09:01:45 -0700") Message-ID: MIME-Version: 1.0 Content-Type: text/plain Sender: linux-fsdevel-owner@vger.kernel.org List-ID: adam.manzanares@wdc.com writes: > From: Adam Manzanares > > This is the per-I/O equivalent of the ioprio_set system call. > > When IOCB_FLAG_IOPRIO is set on the iocb aio_flags field, then we set the > newly added kiocb ki_ioprio field to the value in the iocb aio_reqprio field. > > We set the blkdev bio iopriority unconditionally, so we need to guarantee the > kiocb is initialized properly. Added changes to the loopback driver and > init_sync_kiocb to achieve this. > > This patch depends on block: add ioprio_check_cap function. > > Signed-off-by: Adam Manzanares Reviewed-by: Jeff Moyer > --- > drivers/block/loop.c | 3 +++ > fs/aio.c | 16 ++++++++++++++++ > include/linux/fs.h | 3 +++ > include/uapi/linux/aio_abi.h | 1 + > 4 files changed, 23 insertions(+) > > diff --git a/drivers/block/loop.c b/drivers/block/loop.c > index 5d4e31655d96..dd98dfd97f5e 100644 > --- a/drivers/block/loop.c > +++ b/drivers/block/loop.c > @@ -76,6 +76,8 @@ > #include > #include > #include > +#include > + > #include "loop.h" > > #include > @@ -559,6 +561,7 @@ static int lo_rw_aio(struct loop_device *lo, struct loop_cmd *cmd, > cmd->iocb.ki_filp = file; > cmd->iocb.ki_complete = lo_rw_aio_complete; > cmd->iocb.ki_flags = IOCB_DIRECT; > + cmd->iocb.ki_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_NONE, 0); > if (cmd->css) > kthread_associate_blkcg(cmd->css); > > diff --git a/fs/aio.c b/fs/aio.c > index f3eae5d5771b..44b4572be524 100644 > --- a/fs/aio.c > +++ b/fs/aio.c > @@ -1451,6 +1451,22 @@ static int aio_prep_rw(struct kiocb *req, struct iocb *iocb) > if (iocb->aio_flags & IOCB_FLAG_RESFD) > req->ki_flags |= IOCB_EVENTFD; > req->ki_hint = file_write_hint(req->ki_filp); > + if (iocb->aio_flags & IOCB_FLAG_IOPRIO) { > + /* > + * If the IOCB_FLAG_IOPRIO flag of aio_flags is set, then > + * aio_reqprio is interpreted as an I/O scheduling > + * class and priority. > + */ > + ret = ioprio_check_cap(iocb->aio_reqprio); > + if (ret) { > + pr_debug("aio ioprio check cap error\n"); > + return -EINVAL; > + } > + > + req->ki_ioprio = iocb->aio_reqprio; > + } else > + req->ki_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_NONE, 0); > + > ret = kiocb_set_rw_flags(req, iocb->aio_rw_flags); > if (unlikely(ret)) > fput(req->ki_filp); > diff --git a/include/linux/fs.h b/include/linux/fs.h > index 50de40dbbb85..73b749ed3ea1 100644 > --- a/include/linux/fs.h > +++ b/include/linux/fs.h > @@ -36,6 +36,7 @@ > #include > #include > #include > +#include > > #include > #include > @@ -302,6 +303,7 @@ struct kiocb { > void *private; > int ki_flags; > u16 ki_hint; > + u16 ki_ioprio; /* See linux/ioprio.h */ > } __randomize_layout; > > static inline bool is_sync_kiocb(struct kiocb *kiocb) > @@ -1942,6 +1944,7 @@ static inline void init_sync_kiocb(struct kiocb *kiocb, struct file *filp) > .ki_filp = filp, > .ki_flags = iocb_flags(filp), > .ki_hint = ki_hint_validate(file_write_hint(filp)), > + .ki_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_NONE, 0), > }; > } > > diff --git a/include/uapi/linux/aio_abi.h b/include/uapi/linux/aio_abi.h > index 2c0a3415beee..d4e768d55d14 100644 > --- a/include/uapi/linux/aio_abi.h > +++ b/include/uapi/linux/aio_abi.h > @@ -55,6 +55,7 @@ enum { > * is valid. > */ > #define IOCB_FLAG_RESFD (1 << 0) > +#define IOCB_FLAG_IOPRIO (1 << 1) > > /* read() from /dev/aio returns these structures. */ > struct io_event {