X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=wrapper%2Fpoll.h;h=c26610ea990ca57c1dd97cf5f89064aca771b97c;hb=refs%2Fheads%2Fstable-2.4;hp=416ce5740da7a6e15b88401e209c49dc54860310;hpb=17baffe29814f2508556e498ab8c41a192e76b67;p=lttng-modules.git diff --git a/wrapper/poll.h b/wrapper/poll.h index 416ce574..c26610ea 100644 --- a/wrapper/poll.h +++ b/wrapper/poll.h @@ -1,20 +1,33 @@ +#ifndef _LTTNG_WRAPPER_POLL_H +#define _LTTNG_WRAPPER_POLL_H + /* * wrapper/poll.h * - * Copyright (C) 2010-2011 Mathieu Desnoyers + * Copyright (C) 2011-2012 Mathieu Desnoyers + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; only + * version 2.1 of the License. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. * - * Dual LGPL v2.1/GPL v2 license. + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ -#ifndef CONFIG_LIB_RING_BUFFER #include -#warning "poll_wait_set_exclusive() is defined as no-op. Will increase LTTng overhead. Please consider using the LTTng kernel tree for better results." - /* - * Will cause higher overhead when signalling all possible reader threads when a - * buffer is ready to be consumed. + * Note: poll_wait_set_exclusive() is defined as no-op. Thundering herd + * effect can be noticed with large number of consumer threads. */ + #define poll_wait_set_exclusive(poll_table) -#endif +#endif /* _LTTNG_WRAPPER_POLL_H */