blkdebug: move post-resume handling to resume_req_by_tag

We want to move qemu_coroutine_yield() after the loop on rules,
because QLIST_FOREACH_SAFE is wrong if the rule list is modified
while the coroutine has yielded.  Therefore move the suspended
request to the heap and clean it up from the remove side.
All that is left is for blkdebug_debug_event to handle the
yielding.

Co-developed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20210614082931.24925-3-eesposit@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
This commit is contained in:
Emanuele Giuseppe Esposito 2021-06-14 10:29:27 +02:00 committed by Max Reitz
parent 69d0690c10
commit f48ff5af13

View File

@ -775,25 +775,20 @@ static void blkdebug_close(BlockDriverState *bs)
static void suspend_request(BlockDriverState *bs, BlkdebugRule *rule) static void suspend_request(BlockDriverState *bs, BlkdebugRule *rule)
{ {
BDRVBlkdebugState *s = bs->opaque; BDRVBlkdebugState *s = bs->opaque;
BlkdebugSuspendedReq r; BlkdebugSuspendedReq *r;
r = (BlkdebugSuspendedReq) { r = g_new(BlkdebugSuspendedReq, 1);
.co = qemu_coroutine_self(),
.tag = g_strdup(rule->options.suspend.tag), r->co = qemu_coroutine_self();
}; r->tag = g_strdup(rule->options.suspend.tag);
remove_rule(rule); remove_rule(rule);
QLIST_INSERT_HEAD(&s->suspended_reqs, &r, next); QLIST_INSERT_HEAD(&s->suspended_reqs, r, next);
if (!qtest_enabled()) { if (!qtest_enabled()) {
printf("blkdebug: Suspended request '%s'\n", r.tag); printf("blkdebug: Suspended request '%s'\n", r->tag);
} }
qemu_coroutine_yield(); qemu_coroutine_yield();
if (!qtest_enabled()) {
printf("blkdebug: Resuming request '%s'\n", r.tag);
}
g_free(r.tag);
} }
static bool process_rule(BlockDriverState *bs, struct BlkdebugRule *rule, static bool process_rule(BlockDriverState *bs, struct BlkdebugRule *rule,
@ -880,8 +875,18 @@ retry:
*/ */
QLIST_FOREACH(r, &s->suspended_reqs, next) { QLIST_FOREACH(r, &s->suspended_reqs, next) {
if (!strcmp(r->tag, tag)) { if (!strcmp(r->tag, tag)) {
Coroutine *co = r->co;
if (!qtest_enabled()) {
printf("blkdebug: Resuming request '%s'\n", r->tag);
}
QLIST_REMOVE(r, next); QLIST_REMOVE(r, next);
qemu_coroutine_enter(r->co); g_free(r->tag);
g_free(r);
qemu_coroutine_enter(co);
if (all) { if (all) {
goto retry; goto retry;
} }