From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
To: qemu-block@nongnu.org
Cc: qemu-devel@nongnu.org, vsementsov@virtuozzo.com,
mreitz@redhat.com, kwolf@redhat.com, den@openvz.org
Subject: [PATCH 2/3] qcow2: refactor handle_dependencies() loop body
Date: Sat, 24 Jul 2021 16:38:45 +0300 [thread overview]
Message-ID: <20210724133846.64614-3-vsementsov@virtuozzo.com> (raw)
In-Reply-To: <20210724133846.64614-1-vsementsov@virtuozzo.com>
No logic change, just prepare for the following commit.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
block/qcow2-cluster.c | 49 ++++++++++++++++++++++++-------------------
1 file changed, 28 insertions(+), 21 deletions(-)
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c
index bd0597842f..967121c7e6 100644
--- a/block/qcow2-cluster.c
+++ b/block/qcow2-cluster.c
@@ -1400,29 +1400,36 @@ static int handle_dependencies(BlockDriverState *bs, uint64_t guest_offset,
if (end <= old_start || start >= old_end) {
/* No intersection */
- } else {
- if (start < old_start) {
- /* Stop at the start of a running allocation */
- bytes = old_start - start;
- } else {
- bytes = 0;
- }
+ continue;
+ }
- /* Stop if already an l2meta exists. After yielding, it wouldn't
- * be valid any more, so we'd have to clean up the old L2Metas
- * and deal with requests depending on them before starting to
- * gather new ones. Not worth the trouble. */
- if (bytes == 0 && *m) {
- *cur_bytes = 0;
- return 0;
- }
+ /* Conflict */
- if (bytes == 0) {
- /* Wait for the dependency to complete. We need to recheck
- * the free/allocated clusters when we continue. */
- qemu_co_queue_wait(&old_alloc->dependent_requests, &s->lock);
- return -EAGAIN;
- }
+ if (start < old_start) {
+ /* Stop at the start of a running allocation */
+ bytes = old_start - start;
+ } else {
+ bytes = 0;
+ }
+
+ /*
+ * Stop if already an l2meta exists. After yielding, it wouldn't
+ * be valid any more, so we'd have to clean up the old L2Metas
+ * and deal with requests depending on them before starting to
+ * gather new ones. Not worth the trouble.
+ */
+ if (bytes == 0 && *m) {
+ *cur_bytes = 0;
+ return 0;
+ }
+
+ if (bytes == 0) {
+ /*
+ * Wait for the dependency to complete. We need to recheck
+ * the free/allocated clusters when we continue.
+ */
+ qemu_co_queue_wait(&old_alloc->dependent_requests, &s->lock);
+ return -EAGAIN;
}
}
--
2.29.2
next prev parent reply other threads:[~2021-07-24 13:40 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-24 13:38 [PATCH 0/3] qcow2: relax subclusters allocation dependencies Vladimir Sementsov-Ogievskiy
2021-07-24 13:38 ` [PATCH 1/3] simplebench: add img_bench_templater.py Vladimir Sementsov-Ogievskiy
2021-08-19 16:37 ` Hanna Reitz
2021-08-24 8:53 ` Vladimir Sementsov-Ogievskiy
2021-08-24 8:59 ` Hanna Reitz
2021-08-24 9:09 ` Vladimir Sementsov-Ogievskiy
2021-07-24 13:38 ` Vladimir Sementsov-Ogievskiy [this message]
2021-08-19 17:58 ` [PATCH 2/3] qcow2: refactor handle_dependencies() loop body Eric Blake
2021-08-20 11:03 ` Hanna Reitz
2021-07-24 13:38 ` [PATCH 3/3] qcow2: handle_dependencies(): relax conflict detection Vladimir Sementsov-Ogievskiy
2021-08-19 18:02 ` Eric Blake
2021-08-20 13:21 ` Hanna Reitz
2021-08-23 12:24 ` Vladimir Sementsov-Ogievskiy
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