[ust.git] / libust / tracerconst.h

#ifndef TRACERCONST_H
#define TRACERCONST_H

/* Hardcoded event headers
 *
 * event header for a trace with active heartbeat : 27 bits timestamps
 *
 * headers are 32-bits aligned. In order to insure such alignment, a dynamic per
 * trace alignment value must be done.
 *
 * Remember that the C compiler does align each member on the boundary
 * equivalent to their own size.
 *
 * As relay subbuffers are aligned on pages, we are sure that they are 4 and 8
 * bytes aligned, so the buffer header and trace header are aligned.
 *
 * Event headers are aligned depending on the trace alignment option.
 *
 * Note using C structure bitfields for cross-endianness and portability
 * concerns.
 */

#define LTT_RESERVED_EVENTS	3
#define LTT_EVENT_BITS		5
#define LTT_FREE_EVENTS		((1 << LTT_EVENT_BITS) - LTT_RESERVED_EVENTS)
#define LTT_TSC_BITS		27
#define LTT_TSC_MASK		((1 << LTT_TSC_BITS) - 1)

struct ltt_event_header {
	u32 id_time;		/* 5 bits event id (MSB); 27 bits time (LSB) */
};

/* Reservation flags */
#define	LTT_RFLAG_ID			(1 << 0)
#define	LTT_RFLAG_ID_SIZE		(1 << 1)
#define	LTT_RFLAG_ID_SIZE_TSC		(1 << 2)

#define LTT_MAX_SMALL_SIZE              0xFFFFU

#endif /* TRACERCONST_H */
Commit	Line	Data
b73a4c47 PMF	1	#ifndef TRACERCONST_H
	2	#define TRACERCONST_H
	3
	4	/* Hardcoded event headers
	5	*
	6	* event header for a trace with active heartbeat : 27 bits timestamps
	7	*
	8	* headers are 32-bits aligned. In order to insure such alignment, a dynamic per
	9	* trace alignment value must be done.
	10	*
	11	* Remember that the C compiler does align each member on the boundary
	12	* equivalent to their own size.
	13	*
	14	* As relay subbuffers are aligned on pages, we are sure that they are 4 and 8
	15	* bytes aligned, so the buffer header and trace header are aligned.
	16	*
	17	* Event headers are aligned depending on the trace alignment option.
	18	*
	19	* Note using C structure bitfields for cross-endianness and portability
	20	* concerns.
	21	*/
	22
	23	#define LTT_RESERVED_EVENTS 3
	24	#define LTT_EVENT_BITS 5
	25	#define LTT_FREE_EVENTS ((1 << LTT_EVENT_BITS) - LTT_RESERVED_EVENTS)
	26	#define LTT_TSC_BITS 27
	27	#define LTT_TSC_MASK ((1 << LTT_TSC_BITS) - 1)
	28
	29	struct ltt_event_header {
	30	u32 id_time; /* 5 bits event id (MSB); 27 bits time (LSB) */
	31	};
	32
	33	/* Reservation flags */
	34	#define LTT_RFLAG_ID (1 << 0)
	35	#define LTT_RFLAG_ID_SIZE (1 << 1)
	36	#define LTT_RFLAG_ID_SIZE_TSC (1 << 2)
	37
	38	#define LTT_MAX_SMALL_SIZE 0xFFFFU
	39
	40	#endif /* TRACERCONST_H */