diff options
Diffstat (limited to 'sys/dev/hyperv/vmbus/hv_channel.c')
| -rw-r--r-- | sys/dev/hyperv/vmbus/hv_channel.c | 19 |
1 files changed, 12 insertions, 7 deletions
diff --git a/sys/dev/hyperv/vmbus/hv_channel.c b/sys/dev/hyperv/vmbus/hv_channel.c index bb777cc..a9b7bd4 100644 --- a/sys/dev/hyperv/vmbus/hv_channel.c +++ b/sys/dev/hyperv/vmbus/hv_channel.c @@ -384,17 +384,22 @@ hv_vmbus_channel_establish_gpadl( hv_vmbus_channel_msg_info* curr; uint32_t next_gpadl_handle; - next_gpadl_handle = hv_vmbus_g_connection.next_gpadl_handle; - atomic_add_int((int*) &hv_vmbus_g_connection.next_gpadl_handle, 1); + next_gpadl_handle = atomic_fetchadd_int( + &hv_vmbus_g_connection.next_gpadl_handle, 1); ret = vmbus_channel_create_gpadl_header( contig_buffer, size, &msg_info, &msg_count); - if(ret != 0) { /* if(allocation failed) return immediately */ - /* reverse atomic_add_int above */ - atomic_subtract_int((int*) - &hv_vmbus_g_connection.next_gpadl_handle, 1); - return ret; + if(ret != 0) { + /* + * XXX + * We can _not_ even revert the above incremental, + * if multiple GPADL establishments are running + * parallelly, decrement the global next_gpadl_handle + * is calling for _big_ trouble. A better solution + * is to have a 0-based GPADL id bitmap ... + */ + return ret; } sema_init(&msg_info->wait_sema, 0, "Open Info Sema"); |
