From: Peter Xu <peterx@redhat.com>
To: qemu-devel@nongnu.org
Cc: "Li Zhijian" <lizhijian@fujitsu.com>,
"Hailiang Zhang" <zhanghailiang@xfusion.com>,
"Kevin Wolf" <kwolf@redhat.com>,
"Vladimir Sementsov-Ogievskiy" <vsementsov@yandex-team.ru>,
peterx@redhat.com, "Daniel P . Berrangé" <berrange@redhat.com>,
"Fabiano Rosas" <farosas@suse.de>,
"Zhang Chen" <zhangckid@gmail.com>,
"Dr . David Alan Gilbert" <dave@treblig.org>,
"Prasad Pandit" <ppandit@redhat.com>,
"Paolo Bonzini" <pbonzini@redhat.com>,
"Yury Kotov" <yury-kotov@yandex-team.ru>,
"Juraj Marcin" <jmarcin@redhat.com>
Subject: [PATCH 09/13] migration/rdma: Remove coroutine path in qemu_rdma_wait_comp_channel
Date: Wed, 22 Oct 2025 15:26:08 -0400 [thread overview]
Message-ID: <20251022192612.2737648-10-peterx@redhat.com> (raw)
In-Reply-To: <20251022192612.2737648-1-peterx@redhat.com>
Now after thread-ified dest VM load during precopy, we will always in a
thread context rather than within a coroutine. We can remove this path
now.
Reviewed-by: Zhijian Li (Fujitsu) <lizhijian@fujitsu.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
---
migration/rdma.c | 90 ++++++++++++++++++++++--------------------------
1 file changed, 41 insertions(+), 49 deletions(-)
diff --git a/migration/rdma.c b/migration/rdma.c
index 3389f6448b..67119634d7 100644
--- a/migration/rdma.c
+++ b/migration/rdma.c
@@ -29,7 +29,6 @@
#include "qemu/rcu.h"
#include "qemu/sockets.h"
#include "qemu/bitmap.h"
-#include "qemu/coroutine.h"
#include "system/memory.h"
#include <sys/socket.h>
#include <netdb.h>
@@ -1345,61 +1344,54 @@ static int qemu_rdma_wait_comp_channel(RDMAContext *rdma,
{
struct rdma_cm_event *cm_event;
- if (qemu_in_coroutine()) {
- yield_until_fd_readable(comp_channel->fd);
- } else {
- /* This is the source side, we're in a separate thread
- * or destination prior to migration_fd_process_incoming()
- * after postcopy, the destination also in a separate thread.
- * we can't yield; so we have to poll the fd.
- * But we need to be able to handle 'cancel' or an error
- * without hanging forever.
- */
- while (!rdma->errored && !rdma->received_error) {
- GPollFD pfds[2];
- pfds[0].fd = comp_channel->fd;
- pfds[0].events = G_IO_IN | G_IO_HUP | G_IO_ERR;
- pfds[0].revents = 0;
-
- pfds[1].fd = rdma->channel->fd;
- pfds[1].events = G_IO_IN | G_IO_HUP | G_IO_ERR;
- pfds[1].revents = 0;
-
- /* 0.1s timeout, should be fine for a 'cancel' */
- switch (qemu_poll_ns(pfds, 2, 100 * 1000 * 1000)) {
- case 2:
- case 1: /* fd active */
- if (pfds[0].revents) {
- return 0;
- }
+ /*
+ * This is the source or dest side, either during precopy or
+ * postcopy. We're always in a separate thread when reaching here.
+ * Poll the fd. We need to be able to handle 'cancel' or an error
+ * without hanging forever.
+ */
+ while (!rdma->errored && !rdma->received_error) {
+ GPollFD pfds[2];
+ pfds[0].fd = comp_channel->fd;
+ pfds[0].events = G_IO_IN | G_IO_HUP | G_IO_ERR;
+ pfds[0].revents = 0;
+
+ pfds[1].fd = rdma->channel->fd;
+ pfds[1].events = G_IO_IN | G_IO_HUP | G_IO_ERR;
+ pfds[1].revents = 0;
+
+ /* 0.1s timeout, should be fine for a 'cancel' */
+ switch (qemu_poll_ns(pfds, 2, 100 * 1000 * 1000)) {
+ case 2:
+ case 1: /* fd active */
+ if (pfds[0].revents) {
+ return 0;
+ }
- if (pfds[1].revents) {
- if (rdma_get_cm_event(rdma->channel, &cm_event) < 0) {
- return -1;
- }
+ if (pfds[1].revents) {
+ if (rdma_get_cm_event(rdma->channel, &cm_event) < 0) {
+ return -1;
+ }
- if (cm_event->event == RDMA_CM_EVENT_DISCONNECTED ||
- cm_event->event == RDMA_CM_EVENT_DEVICE_REMOVAL) {
- rdma_ack_cm_event(cm_event);
- return -1;
- }
+ if (cm_event->event == RDMA_CM_EVENT_DISCONNECTED ||
+ cm_event->event == RDMA_CM_EVENT_DEVICE_REMOVAL) {
rdma_ack_cm_event(cm_event);
+ return -1;
}
- break;
+ rdma_ack_cm_event(cm_event);
+ }
+ break;
- case 0: /* Timeout, go around again */
- break;
+ case 0: /* Timeout, go around again */
+ break;
- default: /* Error of some type -
- * I don't trust errno from qemu_poll_ns
- */
- return -1;
- }
+ default: /* Error of some type - don't trust errno from qemu_poll_ns */
+ return -1;
+ }
- if (migrate_get_current()->state == MIGRATION_STATUS_CANCELLING) {
- /* Bail out and let the cancellation happen */
- return -1;
- }
+ if (migrate_get_current()->state == MIGRATION_STATUS_CANCELLING) {
+ /* Bail out and let the cancellation happen */
+ return -1;
}
}
--
2.50.1
next prev parent reply other threads:[~2025-10-22 19:27 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-10-22 19:25 [PATCH 00/13] migration: Threadify loadvm process Peter Xu
2025-10-22 19:26 ` [PATCH 01/13] io: Add qio_channel_wait_cond() helper Peter Xu
2025-10-23 13:02 ` Vladimir Sementsov-Ogievskiy
2025-10-24 12:00 ` Daniel P. Berrangé
2025-10-22 19:26 ` [PATCH 02/13] migration: Properly wait on G_IO_IN when peeking messages Peter Xu
2025-10-23 13:07 ` Vladimir Sementsov-Ogievskiy
2025-10-24 12:02 ` Daniel P. Berrangé
2025-10-28 18:16 ` Peter Xu
2025-10-22 19:26 ` [PATCH 03/13] migration/rdma: Fix wrong context in qio_channel_rdma_shutdown() Peter Xu
2025-10-22 19:26 ` [PATCH 04/13] migration/rdma: Allow qemu_rdma_wait_comp_channel work with thread Peter Xu
2025-10-23 13:41 ` Vladimir Sementsov-Ogievskiy
2025-11-03 7:26 ` Zhijian Li (Fujitsu)
2025-10-22 19:26 ` [PATCH 05/13] migration/rdma: Change io_create_watch() to return immediately Peter Xu
2025-11-03 7:32 ` Zhijian Li (Fujitsu)
2025-10-22 19:26 ` [PATCH 06/13] migration: Introduce WITH_BQL_HELD() / WITH_BQL_RELEASED() Peter Xu
2025-10-28 13:27 ` Vladimir Sementsov-Ogievskiy
2025-10-22 19:26 ` [PATCH 07/13] migration: Pass in bql_held information from qemu_loadvm_state() Peter Xu
2025-10-28 14:22 ` Vladimir Sementsov-Ogievskiy
2025-10-22 19:26 ` [PATCH 08/13] migration: Thread-ify precopy vmstate load process Peter Xu
2025-11-04 2:40 ` Zhijian Li (Fujitsu)
2025-10-22 19:26 ` Peter Xu [this message]
2025-10-22 19:26 ` [PATCH 10/13] migration/postcopy: Remove workaround on wait preempt channel Peter Xu
2025-10-22 19:26 ` [PATCH 11/13] migration/ram: Remove workaround on ram yield during load Peter Xu
2025-10-22 19:26 ` [PATCH 12/13] migration: Allow blocking mode for incoming live migration Peter Xu
2025-10-22 19:26 ` [PATCH 13/13] migration/vfio: Drop BQL dependency for loadvm SWITCHOVER_START Peter Xu
2025-10-22 19:29 ` [PATCH 00/13] migration: Threadify loadvm process Peter Xu
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