[ust.git] / libust / channels.h

#ifndef UST_CHANNELS_H
#define UST_CHANNELS_H

/*
 * Copyright (C) 2008 Mathieu Desnoyers (mathieu.desnoyers@polymtl.ca)
 *
 * Dynamic tracer channel allocation.
 *
 * 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; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * 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
 */

#define _LGPL_SOURCE
#include <linux/limits.h>
#include <errno.h>
#include <ust/kcompat/kcompat.h>
#include <ust/core.h>
#include <urcu/list.h>
#include <urcu/ref.h>

#define EVENTS_PER_CHANNEL	65536
#define MAX_CPUS		32

struct ust_trace;

struct ust_buffer;

struct ust_channel {
	/* First 32 bytes cache-hot cacheline */
	struct ust_trace *trace;
	int *buf_struct_shmids;
	struct ust_buffer **buf;
	int overwrite:1;
	/* whether collection is requested upon trace start */
	int request_collection:1;
	int active:1;
	unsigned int n_subbufs_order;
	unsigned long commit_count_mask;	/*
						 * Commit count mask, removing
						 * the MSBs corresponding to
						 * bits used to represent the
						 * subbuffer index.
						 */
	/* End of first 32 bytes cacheline */

	struct urcu_ref urcu_ref;	/* Channel transport reference count */
	size_t subbuf_size;
	int subbuf_size_order;
	unsigned int subbuf_cnt;
	const char *channel_name;
	int n_cpus;

	u32 version;
	size_t alloc_size;
	struct cds_list_head list;
} ____cacheline_aligned;

struct ltt_channel_setting {
	unsigned int subbuf_size;
	unsigned int subbuf_cnt;
	struct urcu_ref urcu_ref;	/* Number of references to structure content */
	struct cds_list_head list;
	unsigned int index;	/* index of channel in trace channel array */
	u16 free_event_id;	/* Next event ID to allocate */
	char name[PATH_MAX];
};

extern int ltt_channels_register(const char *name);
extern int ltt_channels_unregister(const char *name);
extern int ltt_channels_set_default(const char *name,
			     unsigned int subbuf_size,
			     unsigned int subbuf_cnt);
extern const char *ltt_channels_get_name_from_index(unsigned int index);
extern int ltt_channels_get_index_from_name(const char *name);
extern struct ust_channel *ltt_channels_trace_alloc(unsigned int *nr_channels,
						    int overwrite,
						    int request_collection,
						    int active);
extern void ltt_channels_trace_free(struct ust_channel *channels);
extern int _ltt_channels_get_event_id(const char *channel, const char *name);
extern int ltt_channels_get_event_id(const char *channel, const char *name);

extern int ust_channels_overwrite_by_default;
extern int ust_channels_request_collection_by_default;

#endif /* UST_CHANNELS_H */
Commit	Line	Data
	1	#ifndef UST_CHANNELS_H
	2	#define UST_CHANNELS_H
	3
	4	/*
	5	* Copyright (C) 2008 Mathieu Desnoyers (mathieu.desnoyers@polymtl.ca)
	6	*
	7	* Dynamic tracer channel allocation.
	8	*
	9	* This library is free software; you can redistribute it and/or
	10	* modify it under the terms of the GNU Lesser General Public
	11	* License as published by the Free Software Foundation; either
	12	* version 2.1 of the License, or (at your option) any later version.
	13	*
	14	* This library is distributed in the hope that it will be useful,
	15	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	17	* Lesser General Public License for more details.
	18	*
	19	* You should have received a copy of the GNU Lesser General Public
	20	* License along with this library; if not, write to the Free Software
	21	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	22	*/
	23
	24	#define _LGPL_SOURCE
	25	#include <linux/limits.h>
	26	#include <errno.h>
	27	#include <ust/kcompat/kcompat.h>
	28	#include <ust/core.h>
	29	#include <urcu/list.h>
	30	#include <urcu/ref.h>
	31
	32	#define EVENTS_PER_CHANNEL 65536
	33	#define MAX_CPUS 32
	34
	35	struct ust_trace;
	36
	37	struct ust_buffer;
	38
	39	struct ust_channel {
	40	/* First 32 bytes cache-hot cacheline */
	41	struct ust_trace *trace;
	42	int *buf_struct_shmids;
	43	struct ust_buffer **buf;
	44	int overwrite:1;
	45	/* whether collection is requested upon trace start */
	46	int request_collection:1;
	47	int active:1;
	48	unsigned int n_subbufs_order;
	49	unsigned long commit_count_mask; /*
	50	* Commit count mask, removing
	51	* the MSBs corresponding to
	52	* bits used to represent the
	53	* subbuffer index.
	54	*/
	55	/* End of first 32 bytes cacheline */
	56
	57	struct urcu_ref urcu_ref; /* Channel transport reference count */
	58	size_t subbuf_size;
	59	int subbuf_size_order;
	60	unsigned int subbuf_cnt;
	61	const char *channel_name;
	62	int n_cpus;
	63
	64	u32 version;
	65	size_t alloc_size;
	66	struct cds_list_head list;
	67	} ____cacheline_aligned;
	68
	69	struct ltt_channel_setting {
	70	unsigned int subbuf_size;
	71	unsigned int subbuf_cnt;
	72	struct urcu_ref urcu_ref; /* Number of references to structure content */
	73	struct cds_list_head list;
	74	unsigned int index; /* index of channel in trace channel array */
	75	u16 free_event_id; /* Next event ID to allocate */
	76	char name[PATH_MAX];
	77	};
	78
	79	extern int ltt_channels_register(const char *name);
	80	extern int ltt_channels_unregister(const char *name);
	81	extern int ltt_channels_set_default(const char *name,
	82	unsigned int subbuf_size,
	83	unsigned int subbuf_cnt);
	84	extern const char *ltt_channels_get_name_from_index(unsigned int index);
	85	extern int ltt_channels_get_index_from_name(const char *name);
	86	extern struct ust_channel ltt_channels_trace_alloc(unsigned int nr_channels,
	87	int overwrite,
	88	int request_collection,
	89	int active);
	90	extern void ltt_channels_trace_free(struct ust_channel *channels);
	91	extern int _ltt_channels_get_event_id(const char channel, const char name);
	92	extern int ltt_channels_get_event_id(const char channel, const char name);
	93
	94	extern int ust_channels_overwrite_by_default;
	95	extern int ust_channels_request_collection_by_default;
	96
	97	#endif /* UST_CHANNELS_H */