u-boot/lib/trace.c

440 lines
11 KiB
C
Raw Normal View History

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (c) 2012 The Chromium OS Authors.
*/
#include <common.h>
#include <mapmem.h>
#include <time.h>
#include <trace.h>
#include <asm/io.h>
#include <asm/sections.h>
DECLARE_GLOBAL_DATA_PTR;
static char trace_enabled __attribute__((section(".data")));
static char trace_inited __attribute__((section(".data")));
/* The header block at the start of the trace memory area */
struct trace_hdr {
int func_count; /* Total number of function call sites */
u64 call_count; /* Total number of tracked function calls */
u64 untracked_count; /* Total number of untracked function calls */
int funcs_used; /* Total number of functions used */
/*
* Call count for each function. This is indexed by the word offset
* of the function from gd->relocaddr
*/
uintptr_t *call_accum;
/* Function trace list */
struct trace_call *ftrace; /* The function call records */
ulong ftrace_size; /* Num. of ftrace records we have space for */
ulong ftrace_count; /* Num. of ftrace records written */
ulong ftrace_too_deep_count; /* Functions that were too deep */
int depth;
int depth_limit;
int max_depth;
};
static struct trace_hdr *hdr; /* Pointer to start of trace buffer */
static inline uintptr_t __attribute__((no_instrument_function))
func_ptr_to_num(void *func_ptr)
{
uintptr_t offset = (uintptr_t)func_ptr;
#ifdef CONFIG_SANDBOX
offset -= (uintptr_t)&_init;
#else
if (gd->flags & GD_FLG_RELOC)
offset -= gd->relocaddr;
else
offset -= CONFIG_SYS_TEXT_BASE;
#endif
return offset / FUNC_SITE_SIZE;
}
#if defined(CONFIG_EFI_LOADER) && defined(CONFIG_ARM)
/**
* trace_gd - the value of the gd register
*/
static volatile gd_t *trace_gd;
/**
* trace_save_gd() - save the value of the gd register
*/
static void __attribute__((no_instrument_function)) trace_save_gd(void)
{
trace_gd = gd;
}
/**
* trace_swap_gd() - swap between U-Boot and application gd register value
*
* An UEFI application may change the value of the register that gd lives in.
* But some of our functions like get_ticks() access this register. So we
* have to set the gd register to the U-Boot value when entering a trace
* point and set it back to the application value when exiting the trace point.
*/
static void __attribute__((no_instrument_function)) trace_swap_gd(void)
{
volatile gd_t *temp_gd = trace_gd;
trace_gd = gd;
set_gd(temp_gd);
}
#else
static void __attribute__((no_instrument_function)) trace_save_gd(void)
{
}
static void __attribute__((no_instrument_function)) trace_swap_gd(void)
{
}
#endif
static void __attribute__((no_instrument_function)) add_ftrace(void *func_ptr,
void *caller, ulong flags)
{
if (hdr->depth > hdr->depth_limit) {
hdr->ftrace_too_deep_count++;
return;
}
if (hdr->ftrace_count < hdr->ftrace_size) {
struct trace_call *rec = &hdr->ftrace[hdr->ftrace_count];
rec->func = func_ptr_to_num(func_ptr);
rec->caller = func_ptr_to_num(caller);
rec->flags = flags | (timer_get_us() & FUNCF_TIMESTAMP_MASK);
}
hdr->ftrace_count++;
}
static void __attribute__((no_instrument_function)) add_textbase(void)
{
if (hdr->ftrace_count < hdr->ftrace_size) {
struct trace_call *rec = &hdr->ftrace[hdr->ftrace_count];
rec->func = CONFIG_SYS_TEXT_BASE;
rec->caller = 0;
rec->flags = FUNCF_TEXTBASE;
}
hdr->ftrace_count++;
}
/**
* __cyg_profile_func_enter() - record function entry
*
* We add to our tally for this function and add to the list of called
* functions.
*
* @func_ptr: pointer to function being entered
* @caller: pointer to function which called this function
*/
void __attribute__((no_instrument_function)) __cyg_profile_func_enter(
void *func_ptr, void *caller)
{
if (trace_enabled) {
int func;
trace_swap_gd();
add_ftrace(func_ptr, caller, FUNCF_ENTRY);
func = func_ptr_to_num(func_ptr);
if (func < hdr->func_count) {
hdr->call_accum[func]++;
hdr->call_count++;
} else {
hdr->untracked_count++;
}
hdr->depth++;
if (hdr->depth > hdr->depth_limit)
hdr->max_depth = hdr->depth;
trace_swap_gd();
}
}
/**
* __cyg_profile_func_exit() - record function exit
*
* @func_ptr: pointer to function being entered
* @caller: pointer to function which called this function
*/
void __attribute__((no_instrument_function)) __cyg_profile_func_exit(
void *func_ptr, void *caller)
{
if (trace_enabled) {
trace_swap_gd();
add_ftrace(func_ptr, caller, FUNCF_EXIT);
hdr->depth--;
trace_swap_gd();
}
}
/**
* trace_list_functions() - produce a list of called functions
*
* The information is written into the supplied buffer - a header followed
* by a list of function records.
*
* @buff: buffer to place list into
* @buff_size: size of buffer
* @needed: returns size of buffer needed, which may be
* greater than buff_size if we ran out of space.
* Return: 0 if ok, -ENOSPC if space was exhausted
*/
int trace_list_functions(void *buff, size_t buff_size, size_t *needed)
{
struct trace_output_hdr *output_hdr = NULL;
void *end, *ptr = buff;
size_t func;
size_t upto;
end = buff ? buff + buff_size : NULL;
/* Place some header information */
if (ptr + sizeof(struct trace_output_hdr) < end)
output_hdr = ptr;
ptr += sizeof(struct trace_output_hdr);
/* Add information about each function */
for (func = upto = 0; func < hdr->func_count; func++) {
size_t calls = hdr->call_accum[func];
if (!calls)
continue;
if (ptr + sizeof(struct trace_output_func) < end) {
struct trace_output_func *stats = ptr;
stats->offset = func * FUNC_SITE_SIZE;
stats->call_count = calls;
upto++;
}
ptr += sizeof(struct trace_output_func);
}
/* Update the header */
if (output_hdr) {
output_hdr->rec_count = upto;
output_hdr->type = TRACE_CHUNK_FUNCS;
}
/* Work out how must of the buffer we used */
*needed = ptr - buff;
if (ptr > end)
return -ENOSPC;
return 0;
}
/**
* trace_list_functions() - produce a list of function calls
*
* The information is written into the supplied buffer - a header followed
* by a list of function records.
*
* @buff: buffer to place list into
* @buff_size: size of buffer
* @needed: returns size of buffer needed, which may be
* greater than buff_size if we ran out of space.
* Return: 0 if ok, -ENOSPC if space was exhausted
*/
int trace_list_calls(void *buff, size_t buff_size, size_t *needed)
{
struct trace_output_hdr *output_hdr = NULL;
void *end, *ptr = buff;
size_t rec, upto;
size_t count;
end = buff ? buff + buff_size : NULL;
/* Place some header information */
if (ptr + sizeof(struct trace_output_hdr) < end)
output_hdr = ptr;
ptr += sizeof(struct trace_output_hdr);
/* Add information about each call */
count = hdr->ftrace_count;
if (count > hdr->ftrace_size)
count = hdr->ftrace_size;
for (rec = upto = 0; rec < count; rec++) {
if (ptr + sizeof(struct trace_call) < end) {
struct trace_call *call = &hdr->ftrace[rec];
struct trace_call *out = ptr;
out->func = call->func * FUNC_SITE_SIZE;
out->caller = call->caller * FUNC_SITE_SIZE;
out->flags = call->flags;
upto++;
}
ptr += sizeof(struct trace_call);
}
/* Update the header */
if (output_hdr) {
output_hdr->rec_count = upto;
output_hdr->type = TRACE_CHUNK_CALLS;
}
/* Work out how must of the buffer we used */
*needed = ptr - buff;
if (ptr > end)
return -ENOSPC;
return 0;
}
/**
* trace_print_stats() - print basic information about tracing
*/
void trace_print_stats(void)
{
ulong count;
#ifndef FTRACE
puts("Warning: make U-Boot with FTRACE to enable function instrumenting.\n");
puts("You will likely get zeroed data here\n");
#endif
if (!trace_inited) {
printf("Trace is disabled\n");
return;
}
print_grouped_ull(hdr->func_count, 10);
puts(" function sites\n");
print_grouped_ull(hdr->call_count, 10);
puts(" function calls\n");
print_grouped_ull(hdr->untracked_count, 10);
puts(" untracked function calls\n");
count = min(hdr->ftrace_count, hdr->ftrace_size);
print_grouped_ull(count, 10);
puts(" traced function calls");
if (hdr->ftrace_count > hdr->ftrace_size) {
printf(" (%lu dropped due to overflow)",
hdr->ftrace_count - hdr->ftrace_size);
}
puts("\n");
printf("%15d maximum observed call depth\n", hdr->max_depth);
printf("%15d call depth limit\n", hdr->depth_limit);
print_grouped_ull(hdr->ftrace_too_deep_count, 10);
puts(" calls not traced due to depth\n");
}
void __attribute__((no_instrument_function)) trace_set_enabled(int enabled)
{
trace_enabled = enabled != 0;
}
/**
* trace_init() - initialize the tracing system and enable it
*
* @buff: Pointer to trace buffer
* @buff_size: Size of trace buffer
* Return: 0 if ok
*/
int __attribute__((no_instrument_function)) trace_init(void *buff,
size_t buff_size)
{
ulong func_count = gd->mon_len / FUNC_SITE_SIZE;
size_t needed;
int was_disabled = !trace_enabled;
trace_save_gd();
if (!was_disabled) {
#ifdef CONFIG_TRACE_EARLY
char *end;
ulong used;
/*
* Copy over the early trace data if we have it. Disable
* tracing while we are doing this.
*/
trace_enabled = 0;
hdr = map_sysmem(CONFIG_TRACE_EARLY_ADDR,
CONFIG_TRACE_EARLY_SIZE);
end = (char *)&hdr->ftrace[min(hdr->ftrace_count,
hdr->ftrace_size)];
used = end - (char *)hdr;
printf("trace: copying %08lx bytes of early data from %x to %08lx\n",
used, CONFIG_TRACE_EARLY_ADDR,
(ulong)map_to_sysmem(buff));
memcpy(buff, hdr, used);
#else
puts("trace: already enabled\n");
return -EALREADY;
#endif
}
hdr = (struct trace_hdr *)buff;
needed = sizeof(*hdr) + func_count * sizeof(uintptr_t);
if (needed > buff_size) {
printf("trace: buffer size %zd bytes: at least %zd needed\n",
buff_size, needed);
return -ENOSPC;
}
if (was_disabled)
memset(hdr, '\0', needed);
hdr->func_count = func_count;
hdr->call_accum = (uintptr_t *)(hdr + 1);
/* Use any remaining space for the timed function trace */
hdr->ftrace = (struct trace_call *)(buff + needed);
hdr->ftrace_size = (buff_size - needed) / sizeof(*hdr->ftrace);
add_textbase();
puts("trace: enabled\n");
hdr->depth_limit = CONFIG_TRACE_CALL_DEPTH_LIMIT;
trace_enabled = 1;
trace_inited = 1;
return 0;
}
#ifdef CONFIG_TRACE_EARLY
/**
* trace_early_init() - initialize the tracing system for early tracing
*
* Return: 0 if ok, -ENOSPC if not enough memory is available
*/
int __attribute__((no_instrument_function)) trace_early_init(void)
{
ulong func_count = gd->mon_len / FUNC_SITE_SIZE;
size_t buff_size = CONFIG_TRACE_EARLY_SIZE;
size_t needed;
/* We can ignore additional calls to this function */
if (trace_enabled)
return 0;
hdr = map_sysmem(CONFIG_TRACE_EARLY_ADDR, CONFIG_TRACE_EARLY_SIZE);
needed = sizeof(*hdr) + func_count * sizeof(uintptr_t);
if (needed > buff_size) {
printf("trace: buffer size is %zd bytes, at least %zd needed\n",
buff_size, needed);
return -ENOSPC;
}
memset(hdr, '\0', needed);
hdr->call_accum = (uintptr_t *)(hdr + 1);
hdr->func_count = func_count;
/* Use any remaining space for the timed function trace */
hdr->ftrace = (struct trace_call *)((char *)hdr + needed);
hdr->ftrace_size = (buff_size - needed) / sizeof(*hdr->ftrace);
add_textbase();
hdr->depth_limit = CONFIG_TRACE_EARLY_CALL_DEPTH_LIMIT;
printf("trace: early enable at %08x\n", CONFIG_TRACE_EARLY_ADDR);
trace_enabled = 1;
return 0;
}
#endif