From: Jens Axboe <axboe@kernel.dk>
To: linux-fsdevel@vger.kernel.org, linux-aio@kvack.org,
linux-block@vger.kernel.org, linux-arch@vger.kernel.org
Cc: hch@lst.de, jmoyer@redhat.com, avi@scylladb.com,
Jens Axboe <axboe@kernel.dk>
Subject: [PATCH 16/16] io_uring: add io_uring_event cache hit information
Date: Mon, 14 Jan 2019 19:55:31 -0700 [thread overview]
Message-ID: <20190115025531.13985-17-axboe@kernel.dk> (raw)
Message-ID: <20190115025531.QGNzarMUaZyWhuxRGiHsJyGTNcL8-ELyKhjTBbkud84@z> (raw)
In-Reply-To: <20190115025531.13985-1-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 fd89fcecd8e2..4a74a40cd134 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -546,11 +546,16 @@ 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_fill_event(req->ctx, req->user_data, res, 0);
+
+ if (res > 0 && (req->flags & REQ_F_FORCE_NONBLOCK))
+ ev_flags = IOCQE_FLAG_CACHEHIT;
+
+ io_cqring_fill_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 3f367be56a9e..71e92026d26c 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 (1 << 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:[~2019-01-15 2:56 UTC|newest]
Thread overview: 66+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-01-15 2:55 (unknown), Jens Axboe
2019-01-15 2:55 ` Jens Axboe
2019-01-15 2:55 ` [PATCH 01/16] fs: add an iopoll method to struct file_operations Jens Axboe
2019-01-15 2:55 ` Jens Axboe
2019-01-15 2:55 ` [PATCH 02/16] block: wire up block device iopoll method Jens Axboe
2019-01-15 2:55 ` Jens Axboe
2019-01-15 2:55 ` [PATCH 03/16] block: add bio_set_polled() helper Jens Axboe
2019-01-15 2:55 ` Jens Axboe
2019-01-15 2:55 ` [PATCH 04/16] iomap: wire up the iopoll method Jens Axboe
2019-01-15 2:55 ` Jens Axboe
2019-01-15 2:55 ` [PATCH 05/16] Add io_uring IO interface Jens Axboe
2019-01-15 2:55 ` Jens Axboe
2019-01-15 16:51 ` Jonathan Corbet
2019-01-15 16:51 ` Jonathan Corbet
2019-01-15 16:55 ` Jens Axboe
2019-01-15 16:55 ` Jens Axboe
2019-01-15 17:26 ` Jens Axboe
2019-01-15 17:26 ` Jens Axboe
2019-01-16 10:41 ` Arnd Bergmann
2019-01-16 10:41 ` Arnd Bergmann
2019-01-16 11:00 ` Arnd Bergmann
2019-01-16 11:00 ` Arnd Bergmann
2019-01-16 15:12 ` Jens Axboe
2019-01-16 15:12 ` Jens Axboe
2019-01-16 15:16 ` Arnd Bergmann
2019-01-16 15:16 ` Arnd Bergmann
2019-01-16 15:25 ` Jens Axboe
2019-01-16 15:25 ` Jens Axboe
2019-01-15 2:55 ` [PATCH 06/16] io_uring: add fsync support Jens Axboe
2019-01-15 2:55 ` Jens Axboe
2019-01-15 2:55 ` [PATCH 07/16] io_uring: support for IO polling Jens Axboe
2019-01-15 2:55 ` Jens Axboe
2019-01-15 2:55 ` [PATCH 08/16] io_uring: add submission side request cache Jens Axboe
2019-01-15 2:55 ` Jens Axboe
2019-01-15 2:55 ` [PATCH 09/16] fs: add fget_many() and fput_many() Jens Axboe
2019-01-15 2:55 ` Jens Axboe
2019-01-15 2:55 ` [PATCH 10/16] io_uring: use fget/fput_many() for file references Jens Axboe
2019-01-15 2:55 ` Jens Axboe
2019-01-15 2:55 ` [PATCH 11/16] io_uring: batch io_kiocb allocation Jens Axboe
2019-01-15 2:55 ` Jens Axboe
2019-01-15 2:55 ` [PATCH 12/16] block: implement bio helper to add iter bvec pages to bio Jens Axboe
2019-01-15 2:55 ` Jens Axboe
2019-01-15 2:55 ` [PATCH 13/16] io_uring: add support for pre-mapped user IO buffers Jens Axboe
2019-01-15 2:55 ` Jens Axboe
2019-01-16 10:53 ` Arnd Bergmann
2019-01-16 15:14 ` Jens Axboe
2019-01-16 15:14 ` Jens Axboe
2019-01-16 15:32 ` Jens Axboe
2019-01-16 15:32 ` Jens Axboe
2019-01-16 15:41 ` Arnd Bergmann
2019-01-16 15:47 ` Jens Axboe
2019-01-16 15:47 ` Jens Axboe
2019-01-15 2:55 ` [PATCH 14/16] io_uring: add submission polling Jens Axboe
2019-01-15 2:55 ` Jens Axboe
2019-01-15 2:55 ` [PATCH 15/16] io_uring: add file registration Jens Axboe
2019-01-15 2:55 ` Jens Axboe
2019-01-16 10:45 ` Arnd Bergmann
2019-01-16 10:45 ` Arnd Bergmann
2019-01-16 15:15 ` Jens Axboe
2019-01-16 15:15 ` Jens Axboe
2019-01-15 2:55 ` Jens Axboe [this message]
2019-01-15 2:55 ` [PATCH 16/16] io_uring: add io_uring_event cache hit information Jens Axboe
-- strict thread matches above, loose matches on Subject: below --
2019-01-12 21:29 [PATCHSET v3] io_uring IO interface Jens Axboe
2019-01-12 21:30 ` [PATCH 16/16] io_uring: add io_uring_event cache hit information Jens Axboe
2019-01-12 21:30 ` Jens Axboe
2019-01-08 16:56 [PATCHSET v1] io_uring IO interface Jens Axboe
2019-01-08 16:56 ` [PATCH 16/16] io_uring: add io_uring_event cache hit information Jens Axboe
2019-01-08 16:56 ` Jens Axboe
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