[lttng-modules.git] / lib / ringbuffer / backend_types.h

#ifndef _LIB_RING_BUFFER_BACKEND_TYPES_H
#define _LIB_RING_BUFFER_BACKEND_TYPES_H

/*
 * lib/ringbuffer/backend_types.h
 *
 * Ring buffer backend (types).
 *
 * Copyright (C) 2008-2012 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
 */

#include <linux/cpumask.h>
#include <linux/types.h>
#include <lttng-kernel-version.h>
#include <lttng-cpuhotplug.h>

struct lib_ring_buffer_backend_page {
	void *virt;			/* page virtual address (cached) */
	unsigned long pfn;		/* page frame number */
};

struct lib_ring_buffer_backend_pages {
	unsigned long mmap_offset;	/* offset of the subbuffer in mmap */
	union v_atomic records_commit;	/* current records committed count */
	union v_atomic records_unread;	/* records to read */
	unsigned long data_size;	/* Amount of data to read from subbuf */
	struct lib_ring_buffer_backend_page p[];
};

struct lib_ring_buffer_backend_subbuffer {
	/* Identifier for subbuf backend pages. Exchanged atomically. */
	unsigned long id;		/* backend subbuffer identifier */
};

struct lib_ring_buffer_backend_counts {
	/*
	 * Counter specific to the sub-buffer location within the ring buffer.
	 * The actual sequence number of the packet within the entire ring
	 * buffer can be derived from the formula nr_subbuffers * seq_cnt +
	 * subbuf_idx.
	 */
	uint64_t seq_cnt;		/* packet sequence number */
};

/*
 * Forward declaration of frontend-specific channel and ring_buffer.
 */
struct channel;
struct lib_ring_buffer;

struct lib_ring_buffer_backend {
	/* Array of ring_buffer_backend_subbuffer for writer */
	struct lib_ring_buffer_backend_subbuffer *buf_wsb;
	/* ring_buffer_backend_subbuffer for reader */
	struct lib_ring_buffer_backend_subbuffer buf_rsb;
	/* Array of lib_ring_buffer_backend_counts for the packet counter */
	struct lib_ring_buffer_backend_counts *buf_cnt;
	/*
	 * Pointer array of backend pages, for whole buffer.
	 * Indexed by ring_buffer_backend_subbuffer identifier (id) index.
	 */
	struct lib_ring_buffer_backend_pages **array;
	unsigned int num_pages_per_subbuf;

	struct channel *chan;		/* Associated channel */
	int cpu;			/* This buffer's cpu. -1 if global. */
	union v_atomic records_read;	/* Number of records read */
	unsigned int allocated:1;	/* is buffer allocated ? */
};

struct channel_backend {
	unsigned long buf_size;		/* Size of the buffer */
	unsigned long subbuf_size;	/* Sub-buffer size */
	unsigned int subbuf_size_order;	/* Order of sub-buffer size */
	unsigned int num_subbuf_order;	/*
					 * Order of number of sub-buffers/buffer
					 * for writer.
					 */
	unsigned int buf_size_order;	/* Order of buffer size */
	unsigned int extra_reader_sb:1;	/* has extra reader subbuffer ? */
	struct lib_ring_buffer *buf;	/* Channel per-cpu buffers */

	unsigned long num_subbuf;	/* Number of sub-buffers for writer */
	u64 start_tsc;			/* Channel creation TSC value */
	void *priv;			/* Client-specific information */
	void *priv_ops;			/* Client-specific ops pointer */
	void (*release_priv_ops)(void *priv_ops);
#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0))
	struct lttng_cpuhp_node cpuhp_prepare;	/* CPU hotplug prepare */
#else
	struct notifier_block cpu_hp_notifier;	 /* CPU hotplug notifier */
#endif
	/*
	 * We need to copy config because the module containing the
	 * source config can vanish before the last reference to this
	 * channel's streams is released.
	 */
	struct lib_ring_buffer_config config; /* Ring buffer configuration */
	cpumask_var_t cpumask;		/* Allocated per-cpu buffers cpumask */
	char name[NAME_MAX];		/* Channel name */
};

#endif /* _LIB_RING_BUFFER_BACKEND_TYPES_H */
Commit	Line	Data
886d51a3 MD	1	#ifndef _LIB_RING_BUFFER_BACKEND_TYPES_H
886d51a3 MD	2	#define _LIB_RING_BUFFER_BACKEND_TYPES_H
f3bc08c5 MD	3
f3bc08c5 MD	4	/*
886d51a3	5	* lib/ringbuffer/backend_types.h
f3bc08c5 MD	6	*
	7	* Ring buffer backend (types).
	8	*
886d51a3 MD	9	* Copyright (C) 2008-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	10	*
	11	* This library is free software; you can redistribute it and/or
	12	* modify it under the terms of the GNU Lesser General Public
	13	* License as published by the Free Software Foundation; only
	14	* version 2.1 of the License.
	15	*
	16	* This library is distributed in the hope that it will be useful,
	17	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	18	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	19	* Lesser General Public License for more details.
	20	*
	21	* You should have received a copy of the GNU Lesser General Public
	22	* License along with this library; if not, write to the Free Software
	23	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
f3bc08c5 MD	24	*/
	25
	26	#include <linux/cpumask.h>
	27	#include <linux/types.h>
1e367326 MD	28	#include <lttng-kernel-version.h>
1e367326 MD	29	#include <lttng-cpuhotplug.h>
f3bc08c5 MD	30
	31	struct lib_ring_buffer_backend_page {
	32	void virt; / page virtual address (cached) */
0112cb7b	33	unsigned long pfn; /* page frame number */
f3bc08c5 MD	34	};
	35
	36	struct lib_ring_buffer_backend_pages {
	37	unsigned long mmap_offset; /* offset of the subbuffer in mmap */
	38	union v_atomic records_commit; /* current records committed count */
	39	union v_atomic records_unread; /* records to read */
	40	unsigned long data_size; /* Amount of data to read from subbuf */
	41	struct lib_ring_buffer_backend_page p[];
	42	};
	43
	44	struct lib_ring_buffer_backend_subbuffer {
	45	/* Identifier for subbuf backend pages. Exchanged atomically. */
	46	unsigned long id; /* backend subbuffer identifier */
	47	};
	48
5b3cf4f9 JD	49	struct lib_ring_buffer_backend_counts {
	50	/*
	51	* Counter specific to the sub-buffer location within the ring buffer.
	52	* The actual sequence number of the packet within the entire ring
	53	* buffer can be derived from the formula nr_subbuffers * seq_cnt +
	54	* subbuf_idx.
	55	*/
	56	uint64_t seq_cnt; /* packet sequence number */
	57	};
	58
f3bc08c5 MD	59	/*
	60	* Forward declaration of frontend-specific channel and ring_buffer.
	61	*/
	62	struct channel;
	63	struct lib_ring_buffer;
	64
	65	struct lib_ring_buffer_backend {
	66	/* Array of ring_buffer_backend_subbuffer for writer */
	67	struct lib_ring_buffer_backend_subbuffer *buf_wsb;
	68	/* ring_buffer_backend_subbuffer for reader */
	69	struct lib_ring_buffer_backend_subbuffer buf_rsb;
5b3cf4f9 JD	70	/* Array of lib_ring_buffer_backend_counts for the packet counter */
5b3cf4f9 JD	71	struct lib_ring_buffer_backend_counts *buf_cnt;
f3bc08c5 MD	72	/*
	73	* Pointer array of backend pages, for whole buffer.
	74	* Indexed by ring_buffer_backend_subbuffer identifier (id) index.
	75	*/
	76	struct lib_ring_buffer_backend_pages **array;
	77	unsigned int num_pages_per_subbuf;
	78
	79	struct channel chan; / Associated channel */
	80	int cpu; /* This buffer's cpu. -1 if global. */
	81	union v_atomic records_read; /* Number of records read */
9cccf98a	82	unsigned int allocated:1; /* is buffer allocated ? */
f3bc08c5 MD	83	};
	84
	85	struct channel_backend {
	86	unsigned long buf_size; /* Size of the buffer */
	87	unsigned long subbuf_size; /* Sub-buffer size */
	88	unsigned int subbuf_size_order; /* Order of sub-buffer size */
	89	unsigned int num_subbuf_order; /*
	90	* Order of number of sub-buffers/buffer
	91	* for writer.
	92	*/
	93	unsigned int buf_size_order; /* Order of buffer size */
9cccf98a	94	unsigned int extra_reader_sb:1; /* has extra reader subbuffer ? */
f3bc08c5 MD	95	struct lib_ring_buffer buf; / Channel per-cpu buffers */
	96
	97	unsigned long num_subbuf; /* Number of sub-buffers for writer */
	98	u64 start_tsc; /* Channel creation TSC value */
	99	void priv; / Client-specific information */
dd5a0db3 MD	100	void priv_ops; / Client-specific ops pointer */
dd5a0db3 MD	101	void (release_priv_ops)(void priv_ops);
1e367326 MD	102	#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0))
	103	struct lttng_cpuhp_node cpuhp_prepare; /* CPU hotplug prepare */
	104	#else
f3bc08c5	105	struct notifier_block cpu_hp_notifier; /* CPU hotplug notifier */
1e367326	106	#endif
5a8fd222 MD	107	/*
	108	* We need to copy config because the module containing the
	109	* source config can vanish before the last reference to this
	110	* channel's streams is released.
	111	*/
	112	struct lib_ring_buffer_config config; /* Ring buffer configuration */
f3bc08c5 MD	113	cpumask_var_t cpumask; /* Allocated per-cpu buffers cpumask */
	114	char name[NAME_MAX]; /* Channel name */
	115	};
	116
886d51a3	117	#endif /* _LIB_RING_BUFFER_BACKEND_TYPES_H */