qemu/migration
Fabiano Rosas 93fa9dc2e0 migration/multifd: Add a synchronization point for channel creation
It is possible that one of the multifd channels fails to be created at
multifd_new_send_channel_async() while the rest of the channel
creation tasks are still in flight.

This could lead to multifd_save_cleanup() executing the
qemu_thread_join() loop too early and not waiting for the threads
which haven't been created yet, leading to the freeing of resources
that the newly created threads will try to access and crash.

Add a synchronization point after which there will be no attempts at
thread creation and therefore calling multifd_save_cleanup() past that
point will ensure it properly waits for the threads.

A note about performance: Prior to this patch, if a channel took too
long to be established, other channels could finish connecting first
and already start taking load. Now we're bounded by the
slowest-connecting channel.

Reported-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240206215118.6171-7-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>
2024-02-07 09:53:18 +08:00
..
block-dirty-bitmap.c Replace "iothread lock" with "BQL" in comments 2024-01-08 10:45:43 -05:00
block.c Replace "iothread lock" with "BQL" in comments 2024-01-08 10:45:43 -05:00
block.h
channel-block.c io: follow coroutine AioContext in qio_channel_yield() 2023-09-07 20:32:11 -05:00
channel-block.h migration: introduce a QIOChannel impl for BlockDriverState VMState 2022-06-22 19:33:43 +01:00
channel.c migration: Fix migration_channel_read_peek() error path 2024-01-04 09:52:42 +08:00
channel.h migration: check magic value for deciding the mapping of channels 2023-02-06 19:22:57 +01:00
colo-failover.c migration/colo: Improve an x-colo-lost-heartbeat error message 2023-02-23 14:10:17 +01:00
colo.c Replace "iothread lock" with "BQL" in comments 2024-01-08 10:45:43 -05:00
dirtyrate.c system/cpus: rename qemu_mutex_lock_iothread() to bql_lock() 2024-01-08 10:45:43 -05:00
dirtyrate.h migration/calc-dirty-rate: millisecond-granularity period 2023-10-10 08:03:50 +08:00
exec.c migration: convert exec backend to accept MigrateAddress. 2023-11-02 11:35:04 +01:00
exec.h migration: convert exec backend to accept MigrateAddress. 2023-11-02 11:35:04 +01:00
fd.c bulk: Remove pointless QOM casts 2023-06-05 20:48:34 +02:00
fd.h
file.c migration: Convert the file backend to the new QAPI syntax 2023-11-02 11:35:04 +01:00
file.h migration: Convert the file backend to the new QAPI syntax 2023-11-02 11:35:04 +01:00
global_state.c migration 1st pull for 9.0 2024-01-05 13:35:25 +00:00
meson.build migration: file URI 2023-10-04 13:16:58 +02:00
migration-hmp-cmds.c migration: Plug memory leak on HMP migrate error path 2024-01-29 11:02:12 +08:00
migration-stats.c migration: migration_rate_limit_reset() don't need the QEMUFile 2023-10-31 08:44:33 +01:00
migration-stats.h migration: Remove transferred atomic counter 2023-10-31 08:44:33 +01:00
migration.c migration/multifd: Move multifd_send_setup into migration thread 2024-02-07 09:53:18 +08:00
migration.h migration: Centralize BH creation and dispatch 2024-01-29 11:02:12 +08:00
multifd-zlib.c migration/multifd: Move header prepare/fill into send_prepare() 2024-02-05 14:42:10 +08:00
multifd-zstd.c migration/multifd: Move header prepare/fill into send_prepare() 2024-02-05 14:42:10 +08:00
multifd.c migration/multifd: Add a synchronization point for channel creation 2024-02-07 09:53:18 +08:00
multifd.h migration/multifd: Move multifd_send_setup error handling in to the function 2024-02-07 09:53:18 +08:00
options.c migration: fix coverity migrate_mode finding 2024-01-04 09:52:42 +08:00
options.h migration: mode parameter 2023-11-01 16:13:58 +01:00
page_cache.c migration: Fix cache_init()'s "Failed to allocate" error messages 2021-02-08 11:19:51 +00:00
page_cache.h migration: Clean up signed vs. unsigned XBZRLE cache-size 2021-02-08 11:19:51 +00:00
postcopy-ram.c userfaultfd: use 1ULL to build ioctl masks 2024-01-29 11:02:12 +08:00
postcopy-ram.h migration: Allow postcopy_ram_supported_by_host() to report err 2023-04-27 10:18:25 +02:00
qemu-file.c migration: Refactor error handling in source return path 2023-11-02 11:35:03 +01:00
qemu-file.h migration: Refactor error handling in source return path 2023-11-02 11:35:03 +01:00
ram-compress.c migration: Rename ram_compressed_pages() to compress_ram_pages() 2023-10-30 17:41:55 +01:00
ram-compress.h migration: Rename ram_compressed_pages() to compress_ram_pages() 2023-10-30 17:41:55 +01:00
ram.c migration/multifd: Change retval of multifd_queue_page() 2024-02-05 14:42:10 +08:00
ram.h migration: Change ram_dirty_bitmap_reload() retval to bool 2023-11-02 11:35:03 +01:00
rdma.c migration/rdma: define htonll/ntohll only if not predefined 2024-01-16 11:16:10 +08:00
rdma.h migration: convert rdma backend to accept MigrateAddress 2023-11-02 11:35:03 +01:00
savevm.c migration: Centralize BH creation and dispatch 2024-01-29 11:02:12 +08:00
savevm.h migration: Add .save_prepare() handler to struct SaveVMHandlers 2023-09-11 08:34:06 +02:00
socket.c migration: convert socket backend to accept MigrateAddress 2023-11-02 11:35:03 +01:00
socket.h migration: convert socket backend to accept MigrateAddress 2023-11-02 11:35:03 +01:00
target.c migration: Add migration prefix to functions in target.c 2023-09-11 08:34:06 +02:00
threadinfo.c migration/multifd: Protect accesses to migration_threads 2023-07-26 10:55:56 +02:00
threadinfo.h migration/multifd: Protect accesses to migration_threads 2023-07-26 10:55:56 +02:00
tls.c migration: Drop unused parameter for migration_tls_client_create() 2023-05-03 11:24:20 +02:00
tls.h migration: Drop unused parameter for migration_tls_client_create() 2023-05-03 11:24:20 +02:00
trace-events migration/multifd: Split multifd_send_terminate_threads() 2024-02-05 14:42:10 +08:00
trace.h trace: switch position of headers to what Meson requires 2020-08-21 06:18:24 -04:00
vmstate-types.c Move CPU softfloat unions to cpu-float.h 2022-04-06 14:31:43 +02:00
vmstate.c migration: Make VMStateDescription.subsections const 2023-12-29 11:17:30 +11:00
xbzrle.c migration/xbzrle: Use i386 host/cpuinfo.h 2023-05-23 16:51:18 -07:00
xbzrle.h migration/xbzrle: Use i386 host/cpuinfo.h 2023-05-23 16:51:18 -07:00
yank_functions.c migration/yank: Use channel features 2024-01-29 11:02:12 +08:00
yank_functions.h migration: Move the yank unregister of channel_close out 2021-07-26 12:45:03 +01:00