diff options
| -rw-r--r-- | migration/migration.c | 41 | ||||
| -rw-r--r-- | migration/migration.h | 19 | ||||
| -rw-r--r-- | migration/postcopy-ram.c | 17 | ||||
| -rw-r--r-- | migration/trace-events | 2 |
4 files changed, 74 insertions, 5 deletions
diff --git a/migration/migration.c b/migration/migration.c index ed122ff8d9..5421042d4a 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -143,6 +143,13 @@ static int migration_maybe_pause(MigrationState *s, int new_state); static void migrate_fd_cancel(MigrationState *s); +static gint page_request_addr_cmp(gconstpointer ap, gconstpointer bp) +{ + uintptr_t a = (uintptr_t) ap, b = (uintptr_t) bp; + + return (a > b) - (a < b); +} + void migration_object_init(void) { MachineState *ms = MACHINE(qdev_get_machine()); @@ -165,6 +172,8 @@ void migration_object_init(void) 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_mutex_init(¤t_incoming->page_request_mutex); + current_incoming->page_requested = g_tree_new(page_request_addr_cmp); if (!migration_object_check(current_migration, &err)) { error_report_err(err); @@ -240,6 +249,11 @@ void migration_incoming_state_destroy(void) qemu_event_reset(&mis->main_thread_load_event); + if (mis->page_requested) { + g_tree_destroy(mis->page_requested); + mis->page_requested = NULL; + } + if (mis->socket_address_list) { qapi_free_SocketAddressList(mis->socket_address_list); mis->socket_address_list = NULL; @@ -354,8 +368,33 @@ int migrate_send_rp_message_req_pages(MigrationIncomingState *mis, } int migrate_send_rp_req_pages(MigrationIncomingState *mis, - RAMBlock *rb, ram_addr_t start) + RAMBlock *rb, ram_addr_t start, uint64_t haddr) { + void *aligned = (void *)(uintptr_t)(haddr & (-qemu_ram_pagesize(rb))); + bool received; + + WITH_QEMU_LOCK_GUARD(&mis->page_request_mutex) { + received = ramblock_recv_bitmap_test_byte_offset(rb, start); + if (!received && !g_tree_lookup(mis->page_requested, aligned)) { + /* + * The page has not been received, and it's not yet in the page + * request list. Queue it. Set the value of element to 1, so that + * things like g_tree_lookup() will return TRUE (1) when found. + */ + g_tree_insert(mis->page_requested, aligned, (gpointer)1); + mis->page_requested_count++; + trace_postcopy_page_req_add(aligned, mis->page_requested_count); + } + } + + /* + * If the page is there, skip sending the message. We don't even need the + * lock because as long as the page arrived, it'll be there forever. + */ + if (received) { + return 0; + } + return migrate_send_rp_message_req_pages(mis, rb, start); } diff --git a/migration/migration.h b/migration/migration.h index 9c1cba98d6..d096b77f74 100644 --- a/migration/migration.h +++ b/migration/migration.h @@ -104,6 +104,23 @@ struct MigrationIncomingState { /* List of listening socket addresses */ SocketAddressList *socket_address_list; + + /* A tree of pages that we requested to the source VM */ + GTree *page_requested; + /* For debugging purpose only, but would be nice to keep */ + int page_requested_count; + /* + * The mutex helps to maintain the requested pages that we sent to the + * source, IOW, to guarantee coherent between the page_requests tree and + * the per-ramblock receivedmap. Note! This does not guarantee consistency + * of the real page copy procedures (using UFFDIO_[ZERO]COPY). E.g., even + * if one bit in receivedmap is cleared, UFFDIO_COPY could have happened + * for that page already. This is intended so that the mutex won't + * serialize and blocked by slow operations like UFFDIO_* ioctls. However + * this should be enough to make sure the page_requested tree always + * contains valid information. + */ + QemuMutex page_request_mutex; }; MigrationIncomingState *migration_incoming_get_current(void); @@ -331,7 +348,7 @@ void migrate_send_rp_shut(MigrationIncomingState *mis, void migrate_send_rp_pong(MigrationIncomingState *mis, uint32_t value); int migrate_send_rp_req_pages(MigrationIncomingState *mis, RAMBlock *rb, - ram_addr_t start); + ram_addr_t start, uint64_t haddr); int migrate_send_rp_message_req_pages(MigrationIncomingState *mis, RAMBlock *rb, ram_addr_t start); void migrate_send_rp_recv_bitmap(MigrationIncomingState *mis, diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c index aed4cdaa38..d3bb3a744b 100644 --- a/migration/postcopy-ram.c +++ b/migration/postcopy-ram.c @@ -684,7 +684,7 @@ int postcopy_request_shared_page(struct PostCopyFD *pcfd, RAMBlock *rb, qemu_ram_get_idstr(rb), rb_offset); return postcopy_wake_shared(pcfd, client_addr, rb); } - migrate_send_rp_req_pages(mis, rb, aligned_rbo); + migrate_send_rp_req_pages(mis, rb, aligned_rbo, client_addr); return 0; } @@ -979,7 +979,8 @@ retry: * Send the request to the source - we want to request one * of our host page sizes (which is >= TPS) */ - ret = migrate_send_rp_req_pages(mis, rb, rb_offset); + ret = migrate_send_rp_req_pages(mis, rb, rb_offset, + msg.arg.pagefault.address); if (ret) { /* May be network failure, try to wait for recovery */ if (ret == -EIO && postcopy_pause_fault_thread(mis)) { @@ -1149,10 +1150,20 @@ static int qemu_ufd_copy_ioctl(MigrationIncomingState *mis, void *host_addr, ret = ioctl(userfault_fd, UFFDIO_ZEROPAGE, &zero_struct); } if (!ret) { + qemu_mutex_lock(&mis->page_request_mutex); ramblock_recv_bitmap_set_range(rb, host_addr, pagesize / qemu_target_page_size()); + /* + * If this page resolves a page fault for a previous recorded faulted + * address, take a special note to maintain the requested page list. + */ + if (g_tree_lookup(mis->page_requested, host_addr)) { + g_tree_remove(mis->page_requested, host_addr); + mis->page_requested_count--; + trace_postcopy_page_req_del(host_addr, mis->page_requested_count); + } + qemu_mutex_unlock(&mis->page_request_mutex); mark_postcopy_blocktime_end((uintptr_t)host_addr); - } return ret; } diff --git a/migration/trace-events b/migration/trace-events index c7755116b8..5f0001f808 100644 --- a/migration/trace-events +++ b/migration/trace-events @@ -162,6 +162,7 @@ postcopy_pause_return_path(void) "" postcopy_pause_return_path_continued(void) "" postcopy_pause_continued(void) "" postcopy_start_set_run(void) "" +postcopy_page_req_add(void *addr, int count) "new page req %p total %d" source_return_path_thread_bad_end(void) "" source_return_path_thread_end(void) "" source_return_path_thread_entry(void) "" @@ -272,6 +273,7 @@ postcopy_ram_incoming_cleanup_blocktime(uint64_t total) "total blocktime %" PRIu postcopy_request_shared_page(const char *sharer, const char *rb, uint64_t rb_offset) "for %s in %s offset 0x%"PRIx64 postcopy_request_shared_page_present(const char *sharer, const char *rb, uint64_t rb_offset) "%s already %s offset 0x%"PRIx64 postcopy_wake_shared(uint64_t client_addr, const char *rb) "at 0x%"PRIx64" in %s" +postcopy_page_req_del(void *addr, int count) "resolved page req %p total %d" get_mem_fault_cpu_index(int cpu, uint32_t pid) "cpu: %d, pid: %u" |