u-boot/include/trace.h
Tom Rini 83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00

104 lines
2.9 KiB
C

/* SPDX-License-Identifier: GPL-2.0+ */
/*
* Copyright (c) 2012 The Chromium OS Authors.
*/
#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);
int trace_early_init(void);
/**
* 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