diff options
| -rw-r--r-- | migration/migration.c | 27 | ||||
| -rw-r--r-- | migration/migration.h | 19 | ||||
| -rw-r--r-- | migration/postcopy-ram.c | 25 | ||||
| -rw-r--r-- | migration/qemu-file.c | 27 | ||||
| -rw-r--r-- | migration/qemu-file.h | 1 | ||||
| -rw-r--r-- | migration/savevm.c | 26 | ||||
| -rw-r--r-- | migration/trace-events | 2 |
7 files changed, 119 insertions, 8 deletions
diff --git a/migration/migration.c b/migration/migration.c index c5f0fdf8f8..3119bd2e4b 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -215,9 +215,11 @@ void migration_object_init(void) current_incoming->postcopy_remote_fds = g_array_new(FALSE, TRUE, sizeof(struct PostCopyFD)); qemu_mutex_init(¤t_incoming->rp_mutex); + qemu_mutex_init(¤t_incoming->postcopy_prio_thread_mutex); qemu_event_init(¤t_incoming->main_thread_load_event, false); qemu_sem_init(¤t_incoming->postcopy_pause_sem_dst, 0); qemu_sem_init(¤t_incoming->postcopy_pause_sem_fault, 0); + qemu_sem_init(¤t_incoming->postcopy_pause_sem_fast_load, 0); qemu_mutex_init(¤t_incoming->page_request_mutex); current_incoming->page_requested = g_tree_new(page_request_addr_cmp); @@ -697,9 +699,9 @@ static bool postcopy_try_recover(void) /* * Here, we only wake up the main loading thread (while the - * fault thread will still be waiting), so that we can receive + * rest threads will still be waiting), so that we can receive * commands from source now, and answer it if needed. The - * fault thread will be woken up afterwards until we are sure + * rest threads will be woken up afterwards until we are sure * that source is ready to reply to page requests. */ qemu_sem_post(&mis->postcopy_pause_sem_dst); @@ -3503,6 +3505,18 @@ static MigThrError postcopy_pause(MigrationState *s) qemu_file_shutdown(file); qemu_fclose(file); + /* + * Do the same to postcopy fast path socket too if there is. No + * locking needed because no racer as long as we do this before setting + * status to paused. + */ + if (s->postcopy_qemufile_src) { + migration_ioc_unregister_yank_from_file(s->postcopy_qemufile_src); + qemu_file_shutdown(s->postcopy_qemufile_src); + qemu_fclose(s->postcopy_qemufile_src); + s->postcopy_qemufile_src = NULL; + } + migrate_set_state(&s->state, s->state, MIGRATION_STATUS_POSTCOPY_PAUSED); @@ -3558,8 +3572,13 @@ static MigThrError migration_detect_error(MigrationState *s) return MIG_THR_ERR_FATAL; } - /* Try to detect any file errors */ - ret = qemu_file_get_error_obj(s->to_dst_file, &local_error); + /* + * Try to detect any file errors. Note that postcopy_qemufile_src will + * be NULL when postcopy preempt is not enabled. + */ + ret = qemu_file_get_error_obj_any(s->to_dst_file, + s->postcopy_qemufile_src, + &local_error); if (!ret) { /* Everything is fine */ assert(!local_error); diff --git a/migration/migration.h b/migration/migration.h index ff714c235f..9220cec6bd 100644 --- a/migration/migration.h +++ b/migration/migration.h @@ -119,6 +119,18 @@ struct MigrationIncomingState { QemuThread postcopy_prio_thread; bool postcopy_prio_thread_created; /* + * Used to sync between the ram load main thread and the fast ram load + * thread. It protects postcopy_qemufile_dst, which is the postcopy + * fast channel. + * + * The ram fast load thread will take it mostly for the whole lifecycle + * because it needs to continuously read data from the channel, and + * it'll only release this mutex if postcopy is interrupted, so that + * the ram load main thread will take this mutex over and properly + * release the broken channel. + */ + QemuMutex postcopy_prio_thread_mutex; + /* * An array of temp host huge pages to be used, one for each postcopy * channel. */ @@ -147,6 +159,13 @@ struct MigrationIncomingState { /* notify PAUSED postcopy incoming migrations to try to continue */ QemuSemaphore postcopy_pause_sem_dst; QemuSemaphore postcopy_pause_sem_fault; + /* + * This semaphore is used to allow the ram fast load thread (only when + * postcopy preempt is enabled) fall into sleep when there's network + * interruption detected. When the recovery is done, the main load + * thread will kick the fast ram load thread using this semaphore. + */ + QemuSemaphore postcopy_pause_sem_fast_load; /* List of listening socket addresses */ SocketAddressList *socket_address_list; diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c index a3561410fe..84f7b1526e 100644 --- a/migration/postcopy-ram.c +++ b/migration/postcopy-ram.c @@ -1580,6 +1580,15 @@ int postcopy_preempt_setup(MigrationState *s, Error **errp) return 0; } +static void postcopy_pause_ram_fast_load(MigrationIncomingState *mis) +{ + trace_postcopy_pause_fast_load(); + qemu_mutex_unlock(&mis->postcopy_prio_thread_mutex); + qemu_sem_wait(&mis->postcopy_pause_sem_fast_load); + qemu_mutex_lock(&mis->postcopy_prio_thread_mutex); + trace_postcopy_pause_fast_load_continued(); +} + void *postcopy_preempt_thread(void *opaque) { MigrationIncomingState *mis = opaque; @@ -1592,11 +1601,23 @@ void *postcopy_preempt_thread(void *opaque) qemu_sem_post(&mis->thread_sync_sem); /* Sending RAM_SAVE_FLAG_EOS to terminate this thread */ - ret = ram_load_postcopy(mis->postcopy_qemufile_dst, RAM_CHANNEL_POSTCOPY); + qemu_mutex_lock(&mis->postcopy_prio_thread_mutex); + while (1) { + ret = ram_load_postcopy(mis->postcopy_qemufile_dst, + RAM_CHANNEL_POSTCOPY); + /* If error happened, go into recovery routine */ + if (ret) { + postcopy_pause_ram_fast_load(mis); + } else { + /* We're done */ + break; + } + } + qemu_mutex_unlock(&mis->postcopy_prio_thread_mutex); rcu_unregister_thread(); trace_postcopy_preempt_thread_exit(); - return ret == 0 ? NULL : (void *)-1; + return NULL; } diff --git a/migration/qemu-file.c b/migration/qemu-file.c index 1e80d496b7..2f266b25cd 100644 --- a/migration/qemu-file.c +++ b/migration/qemu-file.c @@ -161,6 +161,33 @@ int qemu_file_get_error_obj(QEMUFile *f, Error **errp) } /* + * Get last error for either stream f1 or f2 with optional Error*. + * The error returned (non-zero) can be either from f1 or f2. + * + * If any of the qemufile* is NULL, then skip the check on that file. + * + * When there is no error on both qemufile, zero is returned. + */ +int qemu_file_get_error_obj_any(QEMUFile *f1, QEMUFile *f2, Error **errp) +{ + int ret = 0; + + if (f1) { + ret = qemu_file_get_error_obj(f1, errp); + /* If there's already error detected, return */ + if (ret) { + return ret; + } + } + + if (f2) { + ret = qemu_file_get_error_obj(f2, errp); + } + + return ret; +} + +/* * Set the last error for stream f with optional Error* */ void qemu_file_set_error_obj(QEMUFile *f, int ret, Error *err) diff --git a/migration/qemu-file.h b/migration/qemu-file.h index 96e72d8bd8..fa13d04d78 100644 --- a/migration/qemu-file.h +++ b/migration/qemu-file.h @@ -141,6 +141,7 @@ void qemu_file_acct_rate_limit(QEMUFile *f, int64_t len); void qemu_file_set_rate_limit(QEMUFile *f, int64_t new_rate); int64_t qemu_file_get_rate_limit(QEMUFile *f); int qemu_file_get_error_obj(QEMUFile *f, Error **errp); +int qemu_file_get_error_obj_any(QEMUFile *f1, QEMUFile *f2, Error **errp); void qemu_file_set_error_obj(QEMUFile *f, int ret, Error *err); void qemu_file_set_error(QEMUFile *f, int ret); int qemu_file_shutdown(QEMUFile *f); diff --git a/migration/savevm.c b/migration/savevm.c index e3af03cb9b..48e85c052c 100644 --- a/migration/savevm.c +++ b/migration/savevm.c @@ -2117,6 +2117,13 @@ static int loadvm_postcopy_handle_resume(MigrationIncomingState *mis) */ qemu_sem_post(&mis->postcopy_pause_sem_fault); + if (migrate_postcopy_preempt()) { + /* The channel should already be setup again; make sure of it */ + assert(mis->postcopy_qemufile_dst); + /* Kick the fast ram load thread too */ + qemu_sem_post(&mis->postcopy_pause_sem_fast_load); + } + return 0; } @@ -2562,6 +2569,21 @@ static bool postcopy_pause_incoming(MigrationIncomingState *mis) mis->to_src_file = NULL; qemu_mutex_unlock(&mis->rp_mutex); + /* + * NOTE: this must happen before reset the PostcopyTmpPages below, + * otherwise it's racy to reset those fields when the fast load thread + * can be accessing it in parallel. + */ + if (mis->postcopy_qemufile_dst) { + qemu_file_shutdown(mis->postcopy_qemufile_dst); + /* Take the mutex to make sure the fast ram load thread halted */ + qemu_mutex_lock(&mis->postcopy_prio_thread_mutex); + migration_ioc_unregister_yank_from_file(mis->postcopy_qemufile_dst); + qemu_fclose(mis->postcopy_qemufile_dst); + mis->postcopy_qemufile_dst = NULL; + qemu_mutex_unlock(&mis->postcopy_prio_thread_mutex); + } + migrate_set_state(&mis->state, MIGRATION_STATUS_POSTCOPY_ACTIVE, MIGRATION_STATUS_POSTCOPY_PAUSED); @@ -2599,8 +2621,8 @@ retry: while (true) { section_type = qemu_get_byte(f); - if (qemu_file_get_error(f)) { - ret = qemu_file_get_error(f); + ret = qemu_file_get_error_obj_any(f, mis->postcopy_qemufile_dst, NULL); + if (ret) { break; } diff --git a/migration/trace-events b/migration/trace-events index 69f311169a..0e385c3a07 100644 --- a/migration/trace-events +++ b/migration/trace-events @@ -270,6 +270,8 @@ mark_postcopy_blocktime_begin(uint64_t addr, void *dd, uint32_t time, int cpu, i mark_postcopy_blocktime_end(uint64_t addr, void *dd, uint32_t time, int affected_cpu) "addr: 0x%" PRIx64 ", dd: %p, time: %u, affected_cpu: %d" postcopy_pause_fault_thread(void) "" postcopy_pause_fault_thread_continued(void) "" +postcopy_pause_fast_load(void) "" +postcopy_pause_fast_load_continued(void) "" postcopy_ram_fault_thread_entry(void) "" postcopy_ram_fault_thread_exit(void) "" postcopy_ram_fault_thread_fds_core(int baseufd, int quitfd) "ufd: %d quitfd: %d" |