profiler/profilesample.h

/*
 **************************************************************************
 * Copyright (c) 2014, The Linux Foundation. All rights reserved.
 * Permission to use, copy, modify, and/or distribute this software for
 * any purpose with or without fee is hereby granted, provided that the
 * above copyright notice and this permission notice appear in all copies.
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 **************************************************************************
 */

/*
 * profilesample.h
 *	Sample format for profiling
 */

#ifndef	_PROFILE_SAMPLE_H_
#define	_PROFILE_SAMPLE_H_

#define PROFILE_STACK_WORDS 4

/*
 * Each sample is for an enabled thread, not including the profiling thread.
 * HRT thread sampling is optional.
 * Sampled threads may be active or inactive.  Samples are included in thread number
 * order, so each sample interval has a set of samples starting with one from thread 0
 *
 * Samples include bits indicating if this thread is blocked
 */
#define PROFILE_I_BLOCKED_BIT 5
#define PROFILE_I_BLOCKED (1 << PROFILE_I_BLOCKED_BIT)
#define PROFILE_D_BLOCKED_BIT 4
#define PROFILE_D_BLOCKED (1 << PROFILE_D_BLOCKED_BIT)
#define PROFILE_BTB_SHIFT 6

#if !defined __unix__ && !defined __ELF__ && !defined __GNUC_
typedef	unsigned char	uint8_t;
typedef	unsigned short	uint16_t;
typedef	unsigned int	uint32_t;
#endif

struct profile_sample {
	uint32_t pc;		// PC value
	uint32_t pid;		// pid for the current process, or 0 if NOMMU or unmapped space
	uint16_t active;	// threads are active - for accurate counting
	uint16_t d_blocked;	// threads are blocked due to D cache misses : may be removed
	uint16_t i_blocked;	// threads are blocked due to I cache misses
	uint8_t cond_codes;	// for branch prediction
	uint8_t thread;		// 4-bit thread number
	uint32_t a_reg;		// source An if PC points to a calli.  Otherwise a5 contents for parent of leaf function
	uint32_t parent[PROFILE_STACK_WORDS];
				// return addresses from stack, to find the caller
};


/*
 * variables for all components/modules
 */
#ifdef	ARCH_NUM_THREADS
#define PROFILE_MAX_THREADS ARCH_NUM_THREADS
#else
#define PROFILE_MAX_THREADS 12
#endif

/*
 * common variables cross profile components/modules
 */
#define PROFILE_MAX_PACKET_SIZE 1440	// MSS - tcp/ip headers

/*
 * values chosen so all counter values fit in a single 1400 byte UDP packet
 */
#define PROFILE_COUNTERS 8
#define PROFILE_COUNTER_NAME_LENGTH 20
#define PROFILE_MAX_APP_COUNTERS 24

#define PROFILE_MAX_COUNTERS ((PROFILE_MAX_PACKET_SIZE - sizeof(struct profile_header_counters)) / (PROFILE_COUNTER_NAME_LENGTH + 4))

struct profile_counter {
	char name[PROFILE_COUNTER_NAME_LENGTH];
	uint32_t value;
};

/*
 * sampling period info cross all modules -- use extended struct to avoid copy
 */
struct profile_ext_header {
	uint16_t d_blocked;	// threads are blocked due to D cache misses
	uint16_t i_blocked;	// threads are blocked due to I cache misses
	uint16_t high;		// threads were enabled high priority -- unused
	uint16_t enabled_threads;	// threads were enabled at the last sample time
	uint16_t hrt;		// HRT threads
	uint8_t profiler_tid;	// thread running the profile sampler
	uint8_t sample_sets;	// typical 5-8 sets, and may be 9 - see design doc for details
	uint32_t sets_map;	// a set map uses a nibble, 8 maps and 9th is derived
	uint32_t clocks;		// system clock timer at last sample
	uint32_t inst_count[PROFILE_MAX_THREADS]; // sampled instruction counts at most recent sample
	uint32_t stats[PROFILE_COUNTERS]; // contents of the cache statistics counters
};

#endif	// _PROFILE_SAMPLE_H_