"Maciej S. Szmigiero" <m...@maciej.szmigiero.name> writes: > On 30.01.2025 21:19, Fabiano Rosas wrote: >> "Maciej S. Szmigiero" <m...@maciej.szmigiero.name> writes: >> >>> From: "Maciej S. Szmigiero" <maciej.szmigi...@oracle.com> >>> >>> This is an updated v4 patch series of the v3 series located here: >>> https://lore.kernel.org/qemu-devel/cover.1731773021.git.maciej.szmigi...@oracle.com/ >>> >>> Changes from v3: >>> * MigrationLoadThread now returns bool and an Error complex error type >>> instead of just an int. >>> >>> * qemu_loadvm_load_thread_pool now reports error via migrate_set_error() >>> instead of dedicated load_threads_ret variable. >>> >>> * Since the change above uncovered an issue with respect to multifd send >>> channels not terminating TLS session properly QIOChannelTLS now allows >>> gracefully handling this situation. >>> >>> * qemu_loadvm_load_thread_pool state is now part of MigrationIncomingState >>> instead of being stored in global variables. >>> This state now also has its own init/cleanup helpers. >>> >>> * qemu_loadvm_load_thread_pool code is now moved into a separate section >>> of the savevm.c file, marked by an appropriate comment. >>> >>> * thread_pool_free() is now documented to have wait-before-free semantic, >>> which allowed removal of explicit waits from thread pool cleanup paths. >>> >>> * thread_pool_submit_immediate() method was added since this functionality >>> is used by both generic thread pool users in this patch set. >>> >>> * postcopy_ram_listen_thread() now takes BQL around function calls that >>> ultimately call migration methods requiring BQL. >>> This fixes one of QEMU tests failing when explicitly BQL-sensitive code >>> is added later to these methods. >>> >>> * qemu_loadvm_load_state_buffer() now returns a bool value instead of int. >>> >>> * "Send final SYNC only after device state is complete" patch was >>> dropped since Peter implemented equivalent functionality upstream. >>> >>> * "Document the BQL behavior of load SaveVMHandlers" patch was dropped >>> since that's something better done later, separately from this patch set. >>> >>> * Header size is now added to mig_stats.multifd_bytes where it is actually >>> sent in the zero copy case - in multifd_nocomp_send_prepare(). >>> >>> * Spurious wakeups from qemu_cond_wait() are now handled properly as >>> pointed out by Avihai. >>> >>> * VFIO migration FD now allows partial write() completion as pointed out >>> by Avihai. >>> >>> * Patch "vfio/migration: Don't run load cleanup if load setup didn't run" >>> was dropped, instead all objects related to multifd load are now located in >>> their own VFIOMultifd struct which is allocated only if multifd device state >>> transfer is actually in use. >>> >>> * Intermediate VFIOStateBuffers API as suggested by Avihai is now introduced >>> to simplify vfio_load_state_buffer() and vfio_load_bufs_thread(). >>> >>> * Optional VFIO device config state loading interlocking with loading >>> other iterables is now possible due to ARM64 platform VFIO dependency on >>> interrupt controller being loaded first as pointed out by Avihai. >>> >>> * Patch "Multifd device state transfer support - receive side" was split >>> into a few smaller patches as suggested by Cรฉdric. >>> >>> * x-migration-multifd-transfer VFIO property compat changes were moved >>> into a separate patch as suggested by Cรฉdric. >>> >>> * Other small changes, like renamed functions and variables/members, added >>> review tags, code formatting, moved QEMU_LOCK_GUARD() instances closer to >>> actual protected blocks, etc. >>> >>> ======================================================================== >>> >>> This patch set is targeting QEMU 10.0. >>> >>> What's not yet present is documentation update under docs/devel/migration >>> but I didn't want to delay posting the code any longer. >>> Such doc can still be merged later when the design is 100% finalized. >>> >>> ======================================================================== >>> >>> Maciej S. Szmigiero (32): >>> migration: Clarify that {load,save}_cleanup handlers can run without >>> setup >>> thread-pool: Remove thread_pool_submit() function >>> thread-pool: Rename AIO pool functions to *_aio() and data types to >>> *Aio >>> thread-pool: Implement generic (non-AIO) pool support >>> migration: Add MIG_CMD_SWITCHOVER_START and its load handler >>> migration: Add qemu_loadvm_load_state_buffer() and its handler >>> io: tls: Allow terminating the TLS session gracefully with EOF >>> migration/multifd: Allow premature EOF on TLS incoming channels >>> migration: postcopy_ram_listen_thread() needs to take BQL for some >>> calls >>> error: define g_autoptr() cleanup function for the Error type >>> migration: Add thread pool of optional load threads >>> migration/multifd: Split packet into header and RAM data >>> migration/multifd: Device state transfer support - receive side >>> migration/multifd: Make multifd_send() thread safe >>> migration/multifd: Add an explicit MultiFDSendData destructor >>> migration/multifd: Device state transfer support - send side >>> migration/multifd: Add multifd_device_state_supported() >>> migration: Add save_live_complete_precopy_thread handler >>> vfio/migration: Add x-migration-load-config-after-iter VFIO property >>> vfio/migration: Add load_device_config_state_start trace event >>> vfio/migration: Convert bytes_transferred counter to atomic >>> vfio/migration: Multifd device state transfer support - basic types >>> vfio/migration: Multifd device state transfer support - >>> VFIOStateBuffer(s) >>> vfio/migration: Multifd device state transfer - add support checking >>> function >>> vfio/migration: Multifd device state transfer support - receive >>> init/cleanup >>> vfio/migration: Multifd device state transfer support - received >>> buffers queuing >>> vfio/migration: Multifd device state transfer support - load thread >>> vfio/migration: Multifd device state transfer support - config loading >>> support >>> migration/qemu-file: Define g_autoptr() cleanup function for QEMUFile >>> vfio/migration: Multifd device state transfer support - send side >>> vfio/migration: Add x-migration-multifd-transfer VFIO property >>> hw/core/machine: Add compat for x-migration-multifd-transfer VFIO >>> property >>> >>> Peter Xu (1): >>> migration/multifd: Make MultiFDSendData a struct >>> >>> hw/core/machine.c | 2 + >>> hw/vfio/migration.c | 754 ++++++++++++++++++++++++++++- >>> hw/vfio/pci.c | 14 + >>> hw/vfio/trace-events | 11 +- >>> include/block/aio.h | 8 +- >>> include/block/thread-pool.h | 62 ++- >>> include/hw/vfio/vfio-common.h | 7 + >>> include/io/channel-tls.h | 11 + >>> include/migration/client-options.h | 4 + >>> include/migration/misc.h | 16 + >>> include/migration/register.h | 54 ++- >>> include/qapi/error.h | 2 + >>> include/qemu/typedefs.h | 6 + >>> io/channel-tls.c | 6 + >>> migration/colo.c | 3 + >>> migration/meson.build | 1 + >>> migration/migration-hmp-cmds.c | 2 + >>> migration/migration.c | 6 +- >>> migration/migration.h | 7 + >>> migration/multifd-device-state.c | 192 ++++++++ >>> migration/multifd-nocomp.c | 30 +- >>> migration/multifd.c | 248 ++++++++-- >>> migration/multifd.h | 74 ++- >>> migration/options.c | 9 + >>> migration/qemu-file.h | 2 + >>> migration/savevm.c | 195 +++++++- >>> migration/savevm.h | 6 +- >>> migration/trace-events | 1 + >>> scripts/analyze-migration.py | 11 + >>> tests/unit/test-thread-pool.c | 6 +- >>> util/async.c | 6 +- >>> util/thread-pool.c | 184 +++++-- >>> util/trace-events | 6 +- >>> 33 files changed, 1814 insertions(+), 132 deletions(-) >>> create mode 100644 migration/multifd-device-state.c >> >> Hi! >> >> We have build issues: >> >> https://gitlab.com/farosas/qemu/-/pipelines/1649146958 >> > > Looks like that's an issue that qatomics on 64-bit > VFIO bytes transferred counters aren't available on > 32-bit host platforms. > > The easiest way would be probably to change these to > 32-bit counters on 32-bit platforms since they can't > realistically address more memory anyway. > >> And the postcopy/recovery test is failing. It seems the migration >> finishes before the test can issue migrate-pause: >> >> QTEST_QEMU_BINARY=./qemu-system-x86_64 ./tests/qtest/migration-test -p >> /x86_64/migration/postcopy/recovery/plain >> ... >> {"execute": "migrate-start-postcopy"} >> {"return": {}} >> {"secs": 1738267018, "usecs": 860991}, "event": "MIGRATION", "data": >> {"status": "postcopy-active"} >> {"secs": 1738267018, "usecs": 861284}, "event": "STOP" >> {"secs": 1738267017, "usecs": 960322}, "event": "MIGRATION", "data": >> {"status": "active"} >> {"secs": 1738267018, "usecs": 865589}, "event": "MIGRATION", "data": >> {"status": "postcopy-active"} >> {"secs": 1738267099, "usecs": 120971}, "event": "MIGRATION", "data": >> {"status": "completed"} >> {"secs": 1738267099, "usecs": 121154}, "event": "RESUME" >> {"execute": "query-migrate"} >> >> ERROR:../tests/qtest/migration/migration-qmp.c:172:check_migration_status: >> assertion failed (current_status != "completed"): ("completed" != >> "completed") >> > > Hmm, it looks like this failure wasn't showing > in my tests because the test was skipped due to > missing userfaultfd support: > > $ QTEST_QEMU_BINARY=./qemu-system-x86_64 ./tests/qtest/migration-test -p > /x86_64/migration/postcopy/recovery/plain > TAP version 14 > # random seed: R02Sc99a7d93274064bb87f3e0789fbf8326 > # Skipping test: userfaultfd not available > # Start of x86_64 tests > # Start of migration tests > # End of migration tests > # End of x86_64 tests > 1..0 > > Will try to make this test run and investigate the reason for > failure.
This will probably help: sysctl -w vm.unprivileged_userfaultfd=1 I also had broken userfaultfd detection in the tests a while back. But it's fixed now. > > Thanks, > Maciej
