[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[PATCH v4 13/19] migration: Parameter x-postcopy-preempt-break-huge
From: |
Peter Xu |
Subject: |
[PATCH v4 13/19] migration: Parameter x-postcopy-preempt-break-huge |
Date: |
Thu, 31 Mar 2022 11:08:51 -0400 |
Add a parameter that can conditionally disable the "break sending huge
page" behavior in postcopy preemption. By default it's enabled.
It should only be used for debugging purposes, and we should never remove
the "x-" prefix.
Signed-off-by: Peter Xu <peterx@redhat.com>
---
migration/migration.c | 2 ++
migration/migration.h | 7 +++++++
migration/ram.c | 7 +++++++
3 files changed, 16 insertions(+)
diff --git a/migration/migration.c b/migration/migration.c
index 33faa0ff6e..ee3df9e229 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -4330,6 +4330,8 @@ static Property migration_properties[] = {
DEFINE_PROP_SIZE("announce-step", MigrationState,
parameters.announce_step,
DEFAULT_MIGRATE_ANNOUNCE_STEP),
+ DEFINE_PROP_BOOL("x-postcopy-preempt-break-huge", MigrationState,
+ postcopy_preempt_break_huge, true),
/* Migration capabilities */
DEFINE_PROP_MIG_CAP("x-xbzrle", MIGRATION_CAPABILITY_XBZRLE),
diff --git a/migration/migration.h b/migration/migration.h
index f898b8547a..6ee520642f 100644
--- a/migration/migration.h
+++ b/migration/migration.h
@@ -340,6 +340,13 @@ struct MigrationState {
bool send_configuration;
/* Whether we send section footer during migration */
bool send_section_footer;
+ /*
+ * Whether we allow break sending huge pages when postcopy preempt is
+ * enabled. When disabled, we won't interrupt precopy within sending a
+ * host huge page, which is the old behavior of vanilla postcopy.
+ * NOTE: this parameter is ignored if postcopy preempt is not enabled.
+ */
+ bool postcopy_preempt_break_huge;
/* Needed by postcopy-pause state */
QemuSemaphore postcopy_pause_sem;
diff --git a/migration/ram.c b/migration/ram.c
index 518d511874..3400cde6e9 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -2266,11 +2266,18 @@ static int ram_save_target_page(RAMState *rs,
PageSearchStatus *pss)
static bool postcopy_needs_preempt(RAMState *rs, PageSearchStatus *pss)
{
+ MigrationState *ms = migrate_get_current();
+
/* Not enabled eager preempt? Then never do that. */
if (!migrate_postcopy_preempt()) {
return false;
}
+ /* If the user explicitly disabled breaking of huge page, skip */
+ if (!ms->postcopy_preempt_break_huge) {
+ return false;
+ }
+
/* If the ramblock we're sending is a small page? Never bother. */
if (qemu_ram_pagesize(pss->block) == TARGET_PAGE_SIZE) {
return false;
--
2.32.0
- [PATCH v4 07/19] migration: Allow migrate-recover to run multiple times, (continued)
- [PATCH v4 07/19] migration: Allow migrate-recover to run multiple times, Peter Xu, 2022/03/31
- [PATCH v4 09/19] migration: Postcopy preemption preparation on channel creation, Peter Xu, 2022/03/31
- [PATCH v4 08/19] migration: Add postcopy-preempt capability, Peter Xu, 2022/03/31
- [PATCH v4 12/19] migration: Create the postcopy preempt channel asynchronously, Peter Xu, 2022/03/31
- [PATCH v4 11/19] migration: Postcopy recover with preempt enabled, Peter Xu, 2022/03/31
- [PATCH v4 14/19] migration: Add helpers to detect TLS capability, Peter Xu, 2022/03/31
- [PATCH v4 17/19] tests: Add postcopy tls migration test, Peter Xu, 2022/03/31
- [PATCH v4 15/19] migration: Export tls-[creds|hostname|authz] params to cmdline too, Peter Xu, 2022/03/31
- [PATCH v4 10/19] migration: Postcopy preemption enablement, Peter Xu, 2022/03/31
- [PATCH v4 18/19] tests: Add postcopy tls recovery migration test, Peter Xu, 2022/03/31
- [PATCH v4 13/19] migration: Parameter x-postcopy-preempt-break-huge,
Peter Xu <=
- [PATCH v4 03/19] migration: Add pss.postcopy_requested status, Peter Xu, 2022/03/31
- [PATCH v4 01/19] migration: Postpone releasing MigrationState.hostname, Peter Xu, 2022/03/31
- [PATCH v4 02/19] migration: Drop multifd tls_hostname cache, Peter Xu, 2022/03/31
- [PATCH v4 19/19] tests: Add postcopy preempt tests, Peter Xu, 2022/03/31
- [PATCH v4 16/19] migration: Enable TLS for preempt channel, Peter Xu, 2022/03/31