154 lines
5.3 KiB
Diff
154 lines
5.3 KiB
Diff
From 093c4a6834f3ec5a05390a3630ae4edec80885b8 Mon Sep 17 00:00:00 2001
|
|
From: Kevin Wolf <kwolf@redhat.com>
|
|
Date: Fri, 18 Nov 2022 18:40:57 +0100
|
|
Subject: [PATCH 15/31] test-bdrv-drain: Don't yield in
|
|
.bdrv_co_drained_begin/end()
|
|
|
|
RH-Author: Stefano Garzarella <sgarzare@redhat.com>
|
|
RH-MergeRequest: 135: block: Simplify drain to prevent QEMU from crashing during snapshot
|
|
RH-Bugzilla: 2155112
|
|
RH-Acked-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
|
|
RH-Acked-by: Hanna Czenczek <hreitz@redhat.com>
|
|
RH-Acked-by: Kevin Wolf <kwolf@redhat.com>
|
|
RH-Commit: [3/16] 5282d3e13cb85dfb480edb11b7eb2769248465df (sgarzarella/qemu-kvm-c-9-s)
|
|
|
|
We want to change .bdrv_co_drained_begin/end() back to be non-coroutine
|
|
callbacks, so in preparation, avoid yielding in their implementation.
|
|
|
|
This does almost the same as the existing logic in bdrv_drain_invoke(),
|
|
by creating and entering coroutines internally. However, since the test
|
|
case is by far the heaviest user of coroutine code in drain callbacks,
|
|
it is preferable to have the complexity in the test case rather than the
|
|
drain core, which is already complicated enough without this.
|
|
|
|
The behaviour for bdrv_drain_begin() is unchanged because we increase
|
|
bs->in_flight and this is still polled. However, bdrv_drain_end()
|
|
doesn't wait for the spawned coroutine to complete any more. This is
|
|
fine, we don't rely on bdrv_drain_end() restarting all operations
|
|
immediately before the next aio_poll().
|
|
|
|
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
|
|
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
|
|
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
|
|
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
|
|
Message-Id: <20221118174110.55183-3-kwolf@redhat.com>
|
|
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
|
|
(cherry picked from commit 7bce1c299834557bffd92294608ea528648cfe75)
|
|
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
|
|
---
|
|
tests/unit/test-bdrv-drain.c | 64 ++++++++++++++++++++++++++----------
|
|
1 file changed, 46 insertions(+), 18 deletions(-)
|
|
|
|
diff --git a/tests/unit/test-bdrv-drain.c b/tests/unit/test-bdrv-drain.c
|
|
index 09dc4a4891..24f34e24ad 100644
|
|
--- a/tests/unit/test-bdrv-drain.c
|
|
+++ b/tests/unit/test-bdrv-drain.c
|
|
@@ -38,12 +38,22 @@ typedef struct BDRVTestState {
|
|
bool sleep_in_drain_begin;
|
|
} BDRVTestState;
|
|
|
|
+static void coroutine_fn sleep_in_drain_begin(void *opaque)
|
|
+{
|
|
+ BlockDriverState *bs = opaque;
|
|
+
|
|
+ qemu_co_sleep_ns(QEMU_CLOCK_REALTIME, 100000);
|
|
+ bdrv_dec_in_flight(bs);
|
|
+}
|
|
+
|
|
static void coroutine_fn bdrv_test_co_drain_begin(BlockDriverState *bs)
|
|
{
|
|
BDRVTestState *s = bs->opaque;
|
|
s->drain_count++;
|
|
if (s->sleep_in_drain_begin) {
|
|
- qemu_co_sleep_ns(QEMU_CLOCK_REALTIME, 100000);
|
|
+ Coroutine *co = qemu_coroutine_create(sleep_in_drain_begin, bs);
|
|
+ bdrv_inc_in_flight(bs);
|
|
+ aio_co_enter(bdrv_get_aio_context(bs), co);
|
|
}
|
|
}
|
|
|
|
@@ -1916,6 +1926,21 @@ static int coroutine_fn bdrv_replace_test_co_preadv(BlockDriverState *bs,
|
|
return 0;
|
|
}
|
|
|
|
+static void coroutine_fn bdrv_replace_test_drain_co(void *opaque)
|
|
+{
|
|
+ BlockDriverState *bs = opaque;
|
|
+ BDRVReplaceTestState *s = bs->opaque;
|
|
+
|
|
+ /* Keep waking io_co up until it is done */
|
|
+ while (s->io_co) {
|
|
+ aio_co_wake(s->io_co);
|
|
+ s->io_co = NULL;
|
|
+ qemu_coroutine_yield();
|
|
+ }
|
|
+ s->drain_co = NULL;
|
|
+ bdrv_dec_in_flight(bs);
|
|
+}
|
|
+
|
|
/**
|
|
* If .drain_count is 0, wake up .io_co if there is one; and set
|
|
* .was_drained.
|
|
@@ -1926,20 +1951,27 @@ static void coroutine_fn bdrv_replace_test_co_drain_begin(BlockDriverState *bs)
|
|
BDRVReplaceTestState *s = bs->opaque;
|
|
|
|
if (!s->drain_count) {
|
|
- /* Keep waking io_co up until it is done */
|
|
- s->drain_co = qemu_coroutine_self();
|
|
- while (s->io_co) {
|
|
- aio_co_wake(s->io_co);
|
|
- s->io_co = NULL;
|
|
- qemu_coroutine_yield();
|
|
- }
|
|
- s->drain_co = NULL;
|
|
-
|
|
+ s->drain_co = qemu_coroutine_create(bdrv_replace_test_drain_co, bs);
|
|
+ bdrv_inc_in_flight(bs);
|
|
+ aio_co_enter(bdrv_get_aio_context(bs), s->drain_co);
|
|
s->was_drained = true;
|
|
}
|
|
s->drain_count++;
|
|
}
|
|
|
|
+static void coroutine_fn bdrv_replace_test_read_entry(void *opaque)
|
|
+{
|
|
+ BlockDriverState *bs = opaque;
|
|
+ char data;
|
|
+ QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, &data, 1);
|
|
+ int ret;
|
|
+
|
|
+ /* Queue a read request post-drain */
|
|
+ ret = bdrv_replace_test_co_preadv(bs, 0, 1, &qiov, 0);
|
|
+ g_assert(ret >= 0);
|
|
+ bdrv_dec_in_flight(bs);
|
|
+}
|
|
+
|
|
/**
|
|
* Reduce .drain_count, set .was_undrained once it reaches 0.
|
|
* If .drain_count reaches 0 and the node has a backing file, issue a
|
|
@@ -1951,17 +1983,13 @@ static void coroutine_fn bdrv_replace_test_co_drain_end(BlockDriverState *bs)
|
|
|
|
g_assert(s->drain_count > 0);
|
|
if (!--s->drain_count) {
|
|
- int ret;
|
|
-
|
|
s->was_undrained = true;
|
|
|
|
if (bs->backing) {
|
|
- char data;
|
|
- QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, &data, 1);
|
|
-
|
|
- /* Queue a read request post-drain */
|
|
- ret = bdrv_replace_test_co_preadv(bs, 0, 1, &qiov, 0);
|
|
- g_assert(ret >= 0);
|
|
+ Coroutine *co = qemu_coroutine_create(bdrv_replace_test_read_entry,
|
|
+ bs);
|
|
+ bdrv_inc_in_flight(bs);
|
|
+ aio_co_enter(bdrv_get_aio_context(bs), co);
|
|
}
|
|
}
|
|
}
|
|
--
|
|
2.31.1
|
|
|