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/*
* Copyright (c) 2012 The Chromium OS Authors.
*
* SPDX-License-Identifier: GPL-2.0+
*/
#ifndef __TRACE_H
#define __TRACE_H
enum {
/*
* This affects the granularity of our trace. We can bin function
* entry points into groups on the basis that functions typically
* have a minimum size, so entry points can't appear any closer
* than this to each other.
*
* The value here assumes a minimum instruction size of 4 bytes,
* or that instructions are 2 bytes but there are at least 2 of
* them in every function.
*
* Increasing this value reduces the number of functions we can
* resolve, but reduces the size of the uintptr_t array used for
* our function list, which is the length of the code divided by
* this value.
*/
FUNC_SITE_SIZE = 4, /* distance between function sites */
};
enum trace_chunk_type {
TRACE_CHUNK_FUNCS,
TRACE_CHUNK_CALLS,
};
/* A trace record for a function, as written to the profile output file */
struct trace_output_func {
uint32_t offset; /* Function offset into code */
uint32_t call_count; /* Number of times called */
};
/* A header at the start of the trace output buffer */
struct trace_output_hdr {
enum trace_chunk_type type; /* Record type */
uint32_t rec_count; /* Number of records */
};
/* Print statistics about traced function calls */
void trace_print_stats(void);
/**
* Dump a list of functions and call counts into a buffer
*
* Each record in the buffer is a struct trace_func_stats. The 'needed'
* parameter returns the number of bytes needed to complete the operation,
* which may be more than buff_size if your buffer is too small.
*
* @param buff Buffer in which to place data, or NULL to count size
* @param buff_size Size of buffer
* @param needed Returns number of bytes used / needed
* @return 0 if ok, -1 on error (buffer exhausted)
*/
int trace_list_functions(void *buff, int buff_size, unsigned *needed);
/* Flags for ftrace_record */
enum ftrace_flags {
FUNCF_EXIT = 0UL << 30,
FUNCF_ENTRY = 1UL << 30,
FUNCF_TEXTBASE = 2UL << 30,
FUNCF_TIMESTAMP_MASK = 0x3fffffff,
};
#define TRACE_CALL_TYPE(call) ((call)->flags & 0xc0000000UL)
/* Information about a single function entry/exit */
struct trace_call {
uint32_t func; /* Function offset */
uint32_t caller; /* Caller function offset */
uint32_t flags; /* Flags and timestamp */
};
int trace_list_calls(void *buff, int buff_size, unsigned int *needed);
/**
* Turn function tracing on and off
*
* Don't enable trace if it has not been initialised.
*
* @param enabled 1 to enable trace, 0 to disable
*/
void trace_set_enabled(int enabled);
#ifdef CONFIG_TRACE_EARLY
int trace_early_init(void);
#else
static inline int trace_early_init(void)
{
return 0;
}
#endif
/**
* Init the trace system
*
* This should be called after relocation with a suitably large buffer
* (typically as large as the U-Boot text area)
*
* @param buff Pointer to trace buffer
* @param buff_size Size of trace buffer
*/
int trace_init(void *buff, size_t buff_size);
#endif