From: Jens Axboe <axboe@kernel.dk>
To: linux-aio@kvack.org, linux-block@vger.kernel.org,
linux-api@vger.kernel.org
Cc: hch@lst.de, jmoyer@redhat.com, avi@scylladb.com,
jannh@google.com, viro@ZenIV.linux.org.uk,
Jens Axboe <axboe@kernel.dk>
Subject: [PATCH] io_uring: add io_uring_event cache hit information
Date: Mon, 11 Feb 2019 12:00:31 -0700 [thread overview]
Message-ID: <20190211190049.7888-3-axboe@kernel.dk> (raw)
In-Reply-To: <20190211190049.7888-1-axboe@kernel.dk>
Add hint on whether a read was served out of the page cache, or if it
hit media. This is useful for buffered async IO, O_DIRECT reads would
never have this set (for obvious reasons).
If the read hit page cache, cqe->flags will have IOCQE_FLAG_CACHEHIT
set.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
fs/io_uring.c | 7 ++++++-
include/uapi/linux/io_uring.h | 5 +++++
2 files changed, 11 insertions(+), 1 deletion(-)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 00c7c11ca699..8114723517d6 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -611,11 +611,16 @@ static void io_fput(struct io_kiocb *req)
static void io_complete_rw(struct kiocb *kiocb, long res, long res2)
{
struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw);
+ unsigned ev_flags = 0;
kiocb_end_write(kiocb);
io_fput(req);
- io_cqring_add_event(req->ctx, req->user_data, res, 0);
+
+ if (res > 0 && (req->flags & REQ_F_FORCE_NONBLOCK))
+ ev_flags = IOCQE_FLAG_CACHEHIT;
+
+ io_cqring_add_event(req->ctx, req->user_data, res, ev_flags);
io_free_req(req);
}
diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h
index e23408692118..24906e99fdc7 100644
--- a/include/uapi/linux/io_uring.h
+++ b/include/uapi/linux/io_uring.h
@@ -69,6 +69,11 @@ struct io_uring_cqe {
__u32 flags;
};
+/*
+ * io_uring_event->flags
+ */
+#define IOCQE_FLAG_CACHEHIT (1U << 0) /* IO did not hit media */
+
/*
* Magic offsets for the application to mmap the data it needs
*/
--
2.17.1
next prev parent reply other threads:[~2019-02-11 19:00 UTC|newest]
Thread overview: 54+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-02-11 19:00 [PATCHSET v15] io_uring IO interface Jens Axboe
2019-02-11 19:00 ` [PATCH 01/19] fs: add an iopoll method to struct file_operations Jens Axboe
2019-02-11 19:00 ` Jens Axboe [this message]
2019-02-11 19:00 ` [PATCH 02/19] block: wire up block device iopoll method Jens Axboe
2019-02-11 19:00 ` [PATCH 03/19] block: add bio_set_polled() helper Jens Axboe
2019-02-11 19:00 ` [PATCH 04/19] iomap: wire up the iopoll method Jens Axboe
2019-02-11 19:00 ` [PATCH 05/19] Add io_uring IO interface Jens Axboe
2019-02-11 19:00 ` [PATCH 06/19] io_uring: add fsync support Jens Axboe
2019-02-11 19:00 ` [PATCH 07/19] io_uring: support for IO polling Jens Axboe
2019-02-11 19:00 ` [PATCH 08/19] fs: add fget_many() and fput_many() Jens Axboe
2019-02-11 19:00 ` [PATCH 09/19] io_uring: use fget/fput_many() for file references Jens Axboe
2019-02-11 19:00 ` [PATCH 10/19] io_uring: batch io_kiocb allocation Jens Axboe
2019-02-11 19:00 ` [PATCH 11/19] block: implement bio helper to add iter bvec pages to bio Jens Axboe
2019-02-20 22:58 ` Ming Lei
2019-02-21 17:45 ` Jens Axboe
2019-02-26 3:46 ` Eric Biggers
2019-02-26 4:34 ` Jens Axboe
2019-02-26 15:54 ` Jens Axboe
2019-02-27 1:21 ` Ming Lei
2019-02-27 1:47 ` Jens Axboe
2019-02-27 1:53 ` Ming Lei
2019-02-27 1:57 ` Jens Axboe
2019-02-27 2:21 ` Ming Lei
2019-02-27 2:28 ` Jens Axboe
2019-02-27 2:37 ` Ming Lei
2019-02-27 2:43 ` Jens Axboe
2019-02-27 3:09 ` Ming Lei
2019-02-27 3:37 ` Jens Axboe
2019-02-27 3:43 ` Jens Axboe
2019-02-27 3:44 ` Ming Lei
2019-02-27 4:05 ` Jens Axboe
2019-02-27 4:06 ` Jens Axboe
2019-02-27 19:42 ` Christoph Hellwig
2019-02-28 8:37 ` Ming Lei
2019-02-27 23:35 ` Ming Lei
2019-03-08 7:55 ` Christoph Hellwig
2019-03-08 9:12 ` Ming Lei
2019-03-08 8:18 ` Christoph Hellwig
2019-02-11 19:00 ` [PATCH 12/19] io_uring: add support for pre-mapped user IO buffers Jens Axboe
2019-02-19 19:08 ` Jann Horn
2019-02-22 22:29 ` Jens Axboe
2019-02-11 19:00 ` [PATCH 13/19] net: split out functions related to registering inflight socket files Jens Axboe
2019-02-11 19:00 ` [PATCH 14/19] io_uring: add file set registration Jens Axboe
2019-02-19 16:12 ` Jann Horn
2019-02-22 22:29 ` Jens Axboe
2019-02-11 19:00 ` [PATCH 15/19] io_uring: add submission polling Jens Axboe
2019-02-11 19:00 ` [PATCH 16/19] io_uring: add io_kiocb ref count Jens Axboe
2019-02-11 19:00 ` [PATCH 17/19] io_uring: add support for IORING_OP_POLL Jens Axboe
2019-02-11 19:00 ` [PATCH 18/19] io_uring: allow workqueue item to handle multiple buffered requests Jens Axboe
2019-02-11 19:00 ` [PATCH 19/19] io_uring: add io_uring_event cache hit information Jens Axboe
2019-02-21 12:10 ` [PATCHSET v15] io_uring IO interface Marek Majkowski
2019-02-21 17:48 ` Jens Axboe
2019-02-22 15:01 ` Marek Majkowski
2019-02-22 22:32 ` Jens Axboe
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190211190049.7888-3-axboe@kernel.dk \
--to=axboe@kernel.dk \
--cc=avi@scylladb.com \
--cc=hch@lst.de \
--cc=jannh@google.com \
--cc=jmoyer@redhat.com \
--cc=linux-aio@kvack.org \
--cc=linux-api@vger.kernel.org \
--cc=linux-block@vger.kernel.org \
--cc=viro@ZenIV.linux.org.uk \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).