From: Jens Axboe <axboe@kernel.dk>
To: io-uring@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-mm@kvack.org, akpm@linux-foundation.org,
Jens Axboe <axboe@kernel.dk>
Subject: [PATCH 01/15] block: provide plug based way of signaling forced no-wait semantics
Date: Thu, 18 Jun 2020 08:43:41 -0600 [thread overview]
Message-ID: <20200618144355.17324-2-axboe@kernel.dk> (raw)
In-Reply-To: <20200618144355.17324-1-axboe@kernel.dk>
Provide a way for the caller to specify that IO should be marked
with REQ_NOWAIT to avoid blocking on allocation.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
block/blk-core.c | 6 ++++++
include/linux/blkdev.h | 1 +
2 files changed, 7 insertions(+)
diff --git a/block/blk-core.c b/block/blk-core.c
index 03252af8c82c..62a4904db921 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -958,6 +958,7 @@ generic_make_request_checks(struct bio *bio)
struct request_queue *q;
int nr_sectors = bio_sectors(bio);
blk_status_t status = BLK_STS_IOERR;
+ struct blk_plug *plug;
char b[BDEVNAME_SIZE];
might_sleep();
@@ -971,6 +972,10 @@ generic_make_request_checks(struct bio *bio)
goto end_io;
}
+ plug = blk_mq_plug(q, bio);
+ if (plug && plug->nowait)
+ bio->bi_opf |= REQ_NOWAIT;
+
/*
* For a REQ_NOWAIT based request, return -EOPNOTSUPP
* if queue is not a request based queue.
@@ -1800,6 +1805,7 @@ void blk_start_plug(struct blk_plug *plug)
INIT_LIST_HEAD(&plug->cb_list);
plug->rq_count = 0;
plug->multiple_queues = false;
+ plug->nowait = false;
/*
* Store ordering should not be needed here, since a potential
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 8fd900998b4e..6e067dca94cf 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1189,6 +1189,7 @@ struct blk_plug {
struct list_head cb_list; /* md requires an unplug callback */
unsigned short rq_count;
bool multiple_queues;
+ bool nowait;
};
#define BLK_MAX_REQUEST_COUNT 16
#define BLK_PLUG_FLUSH_SIZE (128 * 1024)
--
2.27.0
next prev parent reply other threads:[~2020-06-18 14:44 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-18 14:43 Jens Axboe
2020-06-18 14:43 ` Jens Axboe [this message]
2020-06-18 14:43 ` [PATCH 02/15] io_uring: always plug for any number of IOs Jens Axboe
2020-06-18 14:43 ` [PATCH 03/15] io_uring: catch -EIO from buffered issue request failure Jens Axboe
2020-06-18 14:43 ` [PATCH 04/15] io_uring: re-issue block requests that failed because of resources Jens Axboe
2020-06-19 14:12 ` Pavel Begunkov
2020-06-19 14:22 ` Jens Axboe
2020-06-19 14:30 ` Pavel Begunkov
2020-06-19 14:36 ` Jens Axboe
2020-06-18 14:43 ` [PATCH 05/15] mm: allow read-ahead with IOCB_NOWAIT set Jens Axboe
2020-06-24 1:02 ` Dave Chinner
2020-06-24 1:46 ` Matthew Wilcox
2020-06-24 15:00 ` Jens Axboe
2020-06-24 15:35 ` Jens Axboe
2020-06-24 16:41 ` Matthew Wilcox
2020-06-24 16:44 ` Jens Axboe
2020-07-07 11:38 ` Andreas Grünbacher
2020-07-07 14:31 ` Jens Axboe
2020-08-10 22:56 ` Dave Chinner
2020-08-10 23:03 ` Jens Axboe
2020-06-24 4:38 ` Dave Chinner
2020-06-24 15:01 ` Jens Axboe
2020-06-18 14:43 ` [PATCH 06/15] mm: abstract out wake_page_match() from wake_page_function() Jens Axboe
2020-06-18 14:43 ` [PATCH 07/15] mm: add support for async page locking Jens Axboe
2020-07-07 11:32 ` Andreas Grünbacher
2020-07-07 14:32 ` Jens Axboe
2020-06-18 14:43 ` [PATCH 08/15] mm: support async buffered reads in generic_file_buffered_read() Jens Axboe
2020-06-18 14:43 ` [PATCH 09/15] fs: add FMODE_BUF_RASYNC Jens Axboe
2020-06-18 14:43 ` [PATCH 10/15] block: flag block devices as supporting IOCB_WAITQ Jens Axboe
2020-06-18 14:43 ` [PATCH 11/15] xfs: flag files as supporting buffered async reads Jens Axboe
2020-06-18 14:43 ` [PATCH 12/15] btrfs: " Jens Axboe
2020-06-19 11:11 ` David Sterba
2020-06-18 14:43 ` [PATCH 13/15] ext4: flag " Jens Axboe
2020-06-18 14:43 ` [PATCH 14/15] mm: add kiocb_wait_page_queue_init() helper Jens Axboe
2020-06-18 14:43 ` [PATCH 15/15] io_uring: support true async buffered reads, if file provides it Jens Axboe
2020-06-23 12:39 ` Pavel Begunkov
2020-06-23 14:38 ` Jens Axboe
2020-06-18 14:45 ` [PATCHSET v7 0/12] Add support for async buffered reads Jens Axboe
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