From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
To: qemu-block@nongnu.org
Cc: fam@euphon.net, kwolf@redhat.com, vsementsov@virtuozzo.com,
armbru@redhat.com, qemu-devel@nongnu.org, mreitz@redhat.com,
nsoffer@redhat.com, stefanha@redhat.com, den@openvz.org
Subject: [PATCH v5 06/10] block: introduce BDRV_REQ_NO_WAIT flag
Date: Fri, 21 Aug 2020 17:11:19 +0300 [thread overview]
Message-ID: <20200821141123.28538-7-vsementsov@virtuozzo.com> (raw)
In-Reply-To: <20200821141123.28538-1-vsementsov@virtuozzo.com>
Add flag to make serialising request no wait: if there are conflicting
requests, just return error immediately. It's will be used in upcoming
preallocate filter.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
include/block/block.h | 9 ++++++++-
block/io.c | 11 ++++++++++-
2 files changed, 18 insertions(+), 2 deletions(-)
diff --git a/include/block/block.h b/include/block/block.h
index b8f4e86e8d..877fda06a4 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -67,8 +67,15 @@ typedef enum {
* written to qiov parameter which may be NULL.
*/
BDRV_REQ_PREFETCH = 0x200,
+
+ /*
+ * If we need to wait for other requests, just fail immediately. Used
+ * only together with BDRV_REQ_SERIALISING.
+ */
+ BDRV_REQ_NO_WAIT = 0x400,
+
/* Mask of valid flags */
- BDRV_REQ_MASK = 0x3ff,
+ BDRV_REQ_MASK = 0x7ff,
} BdrvRequestFlags;
typedef struct BlockSizes {
diff --git a/block/io.c b/block/io.c
index dd28befb08..c93b1e98a3 100644
--- a/block/io.c
+++ b/block/io.c
@@ -1912,9 +1912,18 @@ bdrv_co_write_req_prepare(BdrvChild *child, int64_t offset, uint64_t bytes,
assert(!(bs->open_flags & BDRV_O_INACTIVE));
assert((bs->open_flags & BDRV_O_NO_IO) == 0);
assert(!(flags & ~BDRV_REQ_MASK));
+ assert(!((flags & BDRV_REQ_NO_WAIT) && !(flags & BDRV_REQ_SERIALISING)));
if (flags & BDRV_REQ_SERIALISING) {
- bdrv_make_request_serialising(req, bdrv_get_cluster_size(bs));
+ QEMU_LOCK_GUARD(&bs->reqs_lock);
+
+ tracked_request_set_serialising(req, bdrv_get_cluster_size(bs));
+
+ if ((flags & BDRV_REQ_NO_WAIT) && bdrv_find_conflicting_request(req)) {
+ return -EBUSY;
+ }
+
+ bdrv_wait_serialising_requests_locked(req);
} else {
bdrv_wait_serialising_requests(req);
}
--
2.21.3
next prev parent reply other threads:[~2020-08-21 14:16 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-08-21 14:11 [PATCH v5 00/10] preallocate filter Vladimir Sementsov-Ogievskiy
2020-08-21 14:11 ` [PATCH v5 01/10] block: simplify comment to BDRV_REQ_SERIALISING Vladimir Sementsov-Ogievskiy
2020-08-21 14:11 ` [PATCH v5 02/10] block/io.c: drop assertion on double waiting for request serialisation Vladimir Sementsov-Ogievskiy
2020-08-21 14:11 ` [PATCH v5 03/10] block/io: split out bdrv_find_conflicting_request Vladimir Sementsov-Ogievskiy
2020-08-21 14:11 ` [PATCH v5 04/10] block/io: bdrv_wait_serialising_requests_locked: drop extra bs arg Vladimir Sementsov-Ogievskiy
2020-08-21 14:11 ` [PATCH v5 05/10] block: bdrv_mark_request_serialising: split non-waiting function Vladimir Sementsov-Ogievskiy
2020-08-25 12:43 ` Max Reitz
2020-08-21 14:11 ` Vladimir Sementsov-Ogievskiy [this message]
2020-08-25 13:10 ` [PATCH v5 06/10] block: introduce BDRV_REQ_NO_WAIT flag Max Reitz
2020-08-26 6:26 ` Vladimir Sementsov-Ogievskiy
2020-08-26 8:36 ` Max Reitz
2020-08-26 8:57 ` Vladimir Sementsov-Ogievskiy
2020-08-21 14:11 ` [PATCH v5 07/10] block: introduce preallocate filter Vladimir Sementsov-Ogievskiy
2020-08-24 17:52 ` Vladimir Sementsov-Ogievskiy
2020-08-26 7:06 ` Vladimir Sementsov-Ogievskiy
2020-08-25 15:11 ` Max Reitz
2020-08-26 6:49 ` Vladimir Sementsov-Ogievskiy
2020-08-26 8:52 ` Max Reitz
2020-08-26 9:15 ` Vladimir Sementsov-Ogievskiy
2020-08-26 9:58 ` Max Reitz
2020-08-26 11:29 ` Vladimir Sementsov-Ogievskiy
2020-08-26 13:51 ` David Edmondson
2020-08-27 9:19 ` Vladimir Sementsov-Ogievskiy
2020-08-21 14:11 ` [PATCH v5 08/10] iotests.py: add verify_o_direct helper Vladimir Sementsov-Ogievskiy
2020-08-21 17:29 ` Nir Soffer
2020-08-21 14:11 ` [PATCH v5 09/10] iotests.py: add filter_img_check Vladimir Sementsov-Ogievskiy
2020-08-21 14:11 ` [PATCH v5 10/10] iotests: add 298 to test new preallocate filter driver Vladimir Sementsov-Ogievskiy
2020-08-27 21:08 ` [PATCH v5 00/10] preallocate filter Vladimir Sementsov-Ogievskiy
2020-09-01 15:07 ` Max Reitz
2020-09-17 9:00 ` Vladimir Sementsov-Ogievskiy
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=20200821141123.28538-7-vsementsov@virtuozzo.com \
--to=vsementsov@virtuozzo.com \
--cc=armbru@redhat.com \
--cc=den@openvz.org \
--cc=fam@euphon.net \
--cc=kwolf@redhat.com \
--cc=mreitz@redhat.com \
--cc=nsoffer@redhat.com \
--cc=qemu-block@nongnu.org \
--cc=qemu-devel@nongnu.org \
--cc=stefanha@redhat.com \
/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).