From: Peter Xu <peterx@redhat.com>
To: qemu-devel@nongnu.org
Cc: "Dr . David Alan Gilbert" <dave@treblig.org>,
peterx@redhat.com, "Kevin Wolf" <kwolf@redhat.com>,
"Paolo Bonzini" <pbonzini@redhat.com>,
"Daniel P . Berrangé" <berrange@redhat.com>,
"Fabiano Rosas" <farosas@suse.de>,
"Hailiang Zhang" <zhanghailiang@xfusion.com>,
"Yury Kotov" <yury-kotov@yandex-team.ru>,
"Vladimir Sementsov-Ogievskiy" <vsementsov@yandex-team.ru>,
"Prasad Pandit" <ppandit@redhat.com>,
"Zhang Chen" <zhangckid@gmail.com>,
"Li Zhijian" <lizhijian@fujitsu.com>,
"Juraj Marcin" <jmarcin@redhat.com>
Subject: [PATCH RFC 8/9] migration/ram: Remove workaround on ram yield during load
Date: Wed, 27 Aug 2025 16:59:47 -0400 [thread overview]
Message-ID: <20250827205949.364606-9-peterx@redhat.com> (raw)
In-Reply-To: <20250827205949.364606-1-peterx@redhat.com>
This reverts e65cec5e5d97927d22b39167d3e8edeffc771788.
RAM load path had a hack in the past explicitly yield the thread to the
main coroutine when RAM load spinning in a tight loop. Not needed now
because precopy RAM load now happens without the main thread.
Signed-off-by: Peter Xu <peterx@redhat.com>
---
migration/ram.c | 13 +------------
1 file changed, 1 insertion(+), 12 deletions(-)
diff --git a/migration/ram.c b/migration/ram.c
index 7208bc114f..2d9a6d1095 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -4168,7 +4168,7 @@ static int parse_ramblocks(QEMUFile *f, ram_addr_t total_ram_bytes)
static int ram_load_precopy(QEMUFile *f)
{
MigrationIncomingState *mis = migration_incoming_get_current();
- int flags = 0, ret = 0, invalid_flags = 0, i = 0;
+ int flags = 0, ret = 0, invalid_flags = 0;
if (migrate_mapped_ram()) {
invalid_flags |= (RAM_SAVE_FLAG_HOOK | RAM_SAVE_FLAG_MULTIFD_FLUSH |
@@ -4181,17 +4181,6 @@ static int ram_load_precopy(QEMUFile *f)
void *host = NULL, *host_bak = NULL;
uint8_t ch;
- /*
- * Yield periodically to let main loop run, but an iteration of
- * the main loop is expensive, so do it each some iterations
- */
- if ((i & 32767) == 0 && qemu_in_coroutine()) {
- aio_co_schedule(qemu_get_current_aio_context(),
- qemu_coroutine_self());
- qemu_coroutine_yield();
- }
- i++;
-
addr = qemu_get_be64(f);
ret = qemu_file_get_error(f);
if (ret) {
--
2.50.1
next prev parent reply other threads:[~2025-08-27 21:02 UTC|newest]
Thread overview: 45+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-08-27 20:59 [PATCH RFC 0/9] migration: Threadify loadvm process Peter Xu
2025-08-27 20:59 ` [PATCH RFC 1/9] migration/vfio: Remove BQL implication in vfio_multifd_switchover_start() Peter Xu
2025-08-28 18:05 ` Maciej S. Szmigiero
2025-09-16 21:34 ` Fabiano Rosas
2025-08-27 20:59 ` [PATCH RFC 2/9] migration/rdma: Fix wrong context in qio_channel_rdma_shutdown() Peter Xu
2025-09-16 21:41 ` Fabiano Rosas
2025-09-26 1:01 ` Zhijian Li (Fujitsu)
2025-08-27 20:59 ` [PATCH RFC 3/9] migration/rdma: Allow qemu_rdma_wait_comp_channel work with thread Peter Xu
2025-09-16 21:50 ` Fabiano Rosas
2025-09-26 1:02 ` Zhijian Li (Fujitsu)
2025-08-27 20:59 ` [PATCH RFC 4/9] migration/rdma: Change io_create_watch() to return immediately Peter Xu
2025-09-16 22:35 ` Fabiano Rosas
2025-10-08 20:34 ` Peter Xu
2025-09-26 2:39 ` Zhijian Li (Fujitsu)
2025-10-08 20:42 ` Peter Xu
2025-08-27 20:59 ` [PATCH RFC 5/9] migration: Thread-ify precopy vmstate load process Peter Xu
2025-08-27 23:51 ` Dr. David Alan Gilbert
2025-08-29 16:37 ` Peter Xu
2025-09-04 1:38 ` Dr. David Alan Gilbert
2025-10-08 21:02 ` Peter Xu
2025-08-29 8:29 ` Vladimir Sementsov-Ogievskiy
2025-08-29 17:17 ` Peter Xu
2025-09-01 9:35 ` Vladimir Sementsov-Ogievskiy
2025-09-17 18:23 ` Fabiano Rosas
2025-10-09 21:41 ` Peter Xu
2025-09-26 3:41 ` Zhijian Li (Fujitsu)
2025-10-08 21:10 ` Peter Xu
2025-08-27 20:59 ` [PATCH RFC 6/9] migration/rdma: Remove coroutine path in qemu_rdma_wait_comp_channel Peter Xu
2025-09-16 22:39 ` Fabiano Rosas
2025-10-08 21:18 ` Peter Xu
2025-09-26 2:44 ` Zhijian Li (Fujitsu)
2025-08-27 20:59 ` [PATCH RFC 7/9] migration/postcopy: Remove workaround on wait preempt channel Peter Xu
2025-09-17 18:30 ` Fabiano Rosas
2025-08-27 20:59 ` Peter Xu [this message]
2025-09-17 18:31 ` [PATCH RFC 8/9] migration/ram: Remove workaround on ram yield during load Fabiano Rosas
2025-08-27 20:59 ` [PATCH RFC 9/9] migration/rdma: Remove rdma_cm_poll_handler Peter Xu
2025-09-17 18:38 ` Fabiano Rosas
2025-10-08 21:22 ` Peter Xu
2025-09-26 3:38 ` Zhijian Li (Fujitsu)
2025-08-29 8:29 ` [PATCH RFC 0/9] migration: Threadify loadvm process Vladimir Sementsov-Ogievskiy
2025-08-29 17:18 ` Peter Xu
2025-09-04 8:27 ` Zhang Chen
2025-10-08 21:26 ` Peter Xu
2025-09-16 21:32 ` Fabiano Rosas
2025-10-09 16:58 ` Peter Xu
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=20250827205949.364606-9-peterx@redhat.com \
--to=peterx@redhat.com \
--cc=berrange@redhat.com \
--cc=dave@treblig.org \
--cc=farosas@suse.de \
--cc=jmarcin@redhat.com \
--cc=kwolf@redhat.com \
--cc=lizhijian@fujitsu.com \
--cc=pbonzini@redhat.com \
--cc=ppandit@redhat.com \
--cc=qemu-devel@nongnu.org \
--cc=vsementsov@yandex-team.ru \
--cc=yury-kotov@yandex-team.ru \
--cc=zhangckid@gmail.com \
--cc=zhanghailiang@xfusion.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).