Introduce LTTNG_UST_ALLOW_BLOCKING env. var.

[lttng-ust.git] / libringbuffer / frontend.h

diff --git a/libringbuffer/frontend.h b/libringbuffer/frontend.h
index eb95e6225986a759df3e809be09ad6e955222d5a..2a9fd09af2dd9cf7e17395ddf106ce9e66065436 100644 (file)
--- a/libringbuffer/frontend.h
+++ b/libringbuffer/frontend.h
@@ -1,19 +1,32 @@
-#ifndef _LINUX_RING_BUFFER_FRONTEND_H
-#define _LINUX_RING_BUFFER_FRONTEND_H
+#ifndef _LTTNG_RING_BUFFER_FRONTEND_H
+#define _LTTNG_RING_BUFFER_FRONTEND_H
 
 /*
- * linux/ringbuffer/frontend.h
- *
- * (C) Copyright 2005-2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * libringbuffer/frontend.h
  *
  * Ring Buffer Library Synchronization Header (API).
  *
+ * Copyright (C) 2005-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * 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.
+ *
+ * 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
+ *
+ *
  * Author:
  *     Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  *
  * See ring_buffer_frontend.c for more information on wait-free algorithms.
- *
- * Dual LGPL v2.1/GPL v2 license.
  */
 
 #include <urcu/compiler.h>
@@ -52,18 +65,8 @@ struct lttng_ust_shm_handle *channel_create(const struct lttng_ust_lib_ring_buff
                                size_t subbuf_size, size_t num_subbuf,
                                unsigned int switch_timer_interval,
                                unsigned int read_timer_interval,
-                               int *shm_fd, int *wait_fd,
-                               uint64_t *memory_map_size);
-
-/* channel_handle_create - for consumer. */
-extern
-struct lttng_ust_shm_handle *channel_handle_create(int shm_fd, int wait_fd,
-                                       uint64_t memory_map_size);
-
-/* channel_handle_add_stream - for consumer. */
-extern
-int channel_handle_add_stream(struct lttng_ust_shm_handle *handle,
-               int shm_fd, int wait_fd, uint64_t memory_map_size);
+                               const int *stream_fds, int nr_stream_fds,
+                               int64_t blocking_timeout);
 
 /*
  * channel_destroy finalizes all channel's buffers, waits for readers to
@@ -71,7 +74,7 @@ int channel_handle_add_stream(struct lttng_ust_shm_handle *handle,
  */
 extern
 void channel_destroy(struct channel *chan, struct lttng_ust_shm_handle *handle,
-               int shadow);
+               int consumer);
 
 
 /* Buffer read operations */
@@ -90,13 +93,37 @@ extern struct lttng_ust_lib_ring_buffer *channel_get_ring_buffer(
                                struct channel *chan, int cpu,
                                struct lttng_ust_shm_handle *handle,
                                int *shm_fd, int *wait_fd,
+                               int *wakeup_fd,
                                uint64_t *memory_map_size);
+extern
+int ring_buffer_channel_close_wait_fd(const struct lttng_ust_lib_ring_buffer_config *config,
+                       struct channel *chan,
+                       struct lttng_ust_shm_handle *handle);
+extern
+int ring_buffer_channel_close_wakeup_fd(const struct lttng_ust_lib_ring_buffer_config *config,
+                       struct channel *chan,
+                       struct lttng_ust_shm_handle *handle);
+extern
+int ring_buffer_stream_close_wait_fd(const struct lttng_ust_lib_ring_buffer_config *config,
+               struct channel *chan,
+               struct lttng_ust_shm_handle *handle,
+               int cpu);
+extern
+int ring_buffer_stream_close_wakeup_fd(const struct lttng_ust_lib_ring_buffer_config *config,
+               struct channel *chan,
+               struct lttng_ust_shm_handle *handle,
+               int cpu);
+
 extern int lib_ring_buffer_open_read(struct lttng_ust_lib_ring_buffer *buf,
-                                    struct lttng_ust_shm_handle *handle,
-                                    int shadow);
+                                    struct lttng_ust_shm_handle *handle);
 extern void lib_ring_buffer_release_read(struct lttng_ust_lib_ring_buffer *buf,
-                                        struct lttng_ust_shm_handle *handle,
-                                        int shadow);
+                                        struct lttng_ust_shm_handle *handle);
+
+/*
+ * Initialize signals for ring buffer. Should be called early e.g. by
+ * main() in the program to affect all threads.
+ */
+void lib_ringbuffer_signal_init(void);
 
 /*
  * Read sequence: snapshot, many get_subbuf/put_subbuf, move_consumer.
@@ -105,6 +132,11 @@ extern int lib_ring_buffer_snapshot(struct lttng_ust_lib_ring_buffer *buf,
                                    unsigned long *consumed,
                                    unsigned long *produced,
                                    struct lttng_ust_shm_handle *handle);
+extern int lib_ring_buffer_snapshot_sample_positions(
+                                   struct lttng_ust_lib_ring_buffer *buf,
+                                   unsigned long *consumed,
+                                   unsigned long *produced,
+                                   struct lttng_ust_shm_handle *handle);
 extern void lib_ring_buffer_move_consumer(struct lttng_ust_lib_ring_buffer *buf,
                                          unsigned long consumed_new,
                                          struct lttng_ust_shm_handle *handle);
@@ -136,9 +168,14 @@ static inline
 void lib_ring_buffer_put_next_subbuf(struct lttng_ust_lib_ring_buffer *buf,
                                     struct lttng_ust_shm_handle *handle)
 {
+       struct channel *chan;
+
+       chan = shmp(handle, buf->backend.chan);
+       if (!chan)
+               return;
        lib_ring_buffer_put_subbuf(buf, handle);
-       lib_ring_buffer_move_consumer(buf, subbuf_align(buf->cons_snapshot,
-                                                       shmp(handle, buf->backend.chan)), handle);
+       lib_ring_buffer_move_consumer(buf, subbuf_align(buf->cons_snapshot, chan),
+                       handle);
 }
 
 extern void channel_reset(struct channel *chan);
@@ -244,4 +281,4 @@ unsigned long lib_ring_buffer_get_records_read(
        return v_read(config, &buf->backend.records_read);
 }
 
-#endif /* _LINUX_RING_BUFFER_FRONTEND_H */
+#endif /* _LTTNG_RING_BUFFER_FRONTEND_H */