diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Makefile | 1 | ||||
| -rw-r--r-- | lib/trace.c | 379 |
2 files changed, 380 insertions, 0 deletions
diff --git a/lib/Makefile b/lib/Makefile index a94830f..f5a8819 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -71,6 +71,7 @@ COBJS-y += linux_string.o COBJS-$(CONFIG_REGEX) += slre.o COBJS-y += string.o COBJS-y += time.o +COBJS-$(CONFIG_TRACE) += trace.o COBJS-$(CONFIG_BOOTP_PXE) += uuid.o COBJS-y += vsprintf.o COBJS-$(CONFIG_RANDOM_MACADDR) += rand.o diff --git a/lib/trace.c b/lib/trace.c new file mode 100644 index 0000000..e7455bc --- /dev/null +++ b/lib/trace.c @@ -0,0 +1,379 @@ +/* + * Copyright (c) 2012 The Chromium OS Authors. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#include <common.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; +} + +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++; +} + +/** + * This is called on every function entry + * + * We add to our tally for this function and add to the list of called + * functions. + * + * @param func_ptr Pointer to function being entered + * @param 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; + + 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; + } +} + +/** + * This is called on every function exit + * + * We do nothing here. + * + * @param func_ptr Pointer to function being entered + * @param 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) { + add_ftrace(func_ptr, caller, FUNCF_EXIT); + hdr->depth--; + } +} + +/** + * Produce a list of called functions + * + * The information is written into the supplied buffer - a header followed + * by a list of function records. + * + * @param buff Buffer to place list into + * @param buff_size Size of buffer + * @param needed Returns size of buffer needed, which may be + * greater than buff_size if we ran out of space. + * @return 0 if ok, -1 if space was exhausted + */ +int trace_list_functions(void *buff, int buff_size, unsigned int *needed) +{ + struct trace_output_hdr *output_hdr = NULL; + void *end, *ptr = buff; + int func; + int 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++) { + int 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 -1; + return 0; +} + +int trace_list_calls(void *buff, int buff_size, unsigned *needed) +{ + struct trace_output_hdr *output_hdr = NULL; + void *end, *ptr = buff; + int rec, upto; + int 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 -1; + return 0; +} + +/* 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; +} + +/** + * Init the tracing system ready for used, and enable it + * + * @param buff Pointer to trace buffer + * @param buff_size Size of trace buffer + */ +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; + + 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[hdr->ftrace_count]; + 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 -1; +#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 -1; + } + + 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 = 15; + trace_enabled = 1; + trace_inited = 1; + return 0; +} + +#ifdef CONFIG_TRACE_EARLY +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 -1; + } + + 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 = 200; + printf("trace: early enable at %08x\n", CONFIG_TRACE_EARLY_ADDR); + + trace_enabled = 1; + return 0; +} +#endif |