[GitHub/LineageOS/android_kernel_motorola_exynos9610.git] / tools / perf / util / unwind-libdw.c

#include <linux/compiler.h>
#include <elfutils/libdw.h>
#include <elfutils/libdwfl.h>
#include <inttypes.h>
#include <errno.h>
#include "debug.h"
#include "unwind.h"
#include "unwind-libdw.h"
#include "machine.h"
#include "thread.h"
#include <linux/types.h>
#include "event.h"
#include "perf_regs.h"
#include "callchain.h"
#include "util.h"

static char *debuginfo_path;

static const Dwfl_Callbacks offline_callbacks = {
	.find_debuginfo		= dwfl_standard_find_debuginfo,
	.debuginfo_path		= &debuginfo_path,
	.section_address	= dwfl_offline_section_address,
};

static int __report_module(struct addr_location *al, u64 ip,
			    struct unwind_info *ui)
{
	Dwfl_Module *mod;
	struct dso *dso = NULL;

	thread__find_addr_location(ui->thread,
				   PERF_RECORD_MISC_USER,
				   MAP__FUNCTION, ip, al);

	if (al->map)
		dso = al->map->dso;

	if (!dso)
		return 0;

	mod = dwfl_addrmodule(ui->dwfl, ip);
	if (mod) {
		Dwarf_Addr s;

		dwfl_module_info(mod, NULL, &s, NULL, NULL, NULL, NULL, NULL);
		if (s != al->map->start)
			mod = 0;
	}

	if (!mod)
		mod = dwfl_report_elf(ui->dwfl, dso->short_name,
				      dso->long_name, -1, al->map->start,
				      false);

	return mod && dwfl_addrmodule(ui->dwfl, ip) == mod ? 0 : -1;
}

static int report_module(u64 ip, struct unwind_info *ui)
{
	struct addr_location al;

	return __report_module(&al, ip, ui);
}

/*
 * Store all entries within entries array,
 * we will process it after we finish unwind.
 */
static int entry(u64 ip, struct unwind_info *ui)

{
	struct unwind_entry *e = &ui->entries[ui->idx++];
	struct addr_location al;

	if (__report_module(&al, ip, ui))
		return -1;

	e->ip  = al.addr;
	e->map = al.map;
	e->sym = al.sym;

	pr_debug("unwind: %s:ip = 0x%" PRIx64 " (0x%" PRIx64 ")\n",
		 al.sym ? al.sym->name : "''",
		 ip,
		 al.map ? al.map->map_ip(al.map, ip) : (u64) 0);
	return 0;
}

static pid_t next_thread(Dwfl *dwfl, void *arg, void **thread_argp)
{
	/* We want only single thread to be processed. */
	if (*thread_argp != NULL)
		return 0;

	*thread_argp = arg;
	return dwfl_pid(dwfl);
}

static int access_dso_mem(struct unwind_info *ui, Dwarf_Addr addr,
			  Dwarf_Word *data)
{
	struct addr_location al;
	ssize_t size;

	thread__find_addr_map(ui->thread, PERF_RECORD_MISC_USER,
			      MAP__FUNCTION, addr, &al);
	if (!al.map) {
		/*
		 * We've seen cases (softice) where DWARF unwinder went
		 * through non executable mmaps, which we need to lookup
		 * in MAP__VARIABLE tree.
		 */
		thread__find_addr_map(ui->thread, PERF_RECORD_MISC_USER,
				      MAP__VARIABLE, addr, &al);
	}

	if (!al.map) {
		pr_debug("unwind: no map for %lx\n", (unsigned long)addr);
		return -1;
	}

	if (!al.map->dso)
		return -1;

	size = dso__data_read_addr(al.map->dso, al.map, ui->machine,
				   addr, (u8 *) data, sizeof(*data));

	return !(size == sizeof(*data));
}

static bool memory_read(Dwfl *dwfl __maybe_unused, Dwarf_Addr addr, Dwarf_Word *result,
			void *arg)
{
	struct unwind_info *ui = arg;
	struct stack_dump *stack = &ui->sample->user_stack;
	u64 start, end;
	int offset;
	int ret;

	ret = perf_reg_value(&start, &ui->sample->user_regs, PERF_REG_SP);
	if (ret)
		return false;

	end = start + stack->size;

	/* Check overflow. */
	if (addr + sizeof(Dwarf_Word) < addr)
		return false;

	if (addr < start || addr + sizeof(Dwarf_Word) > end) {
		ret = access_dso_mem(ui, addr, result);
		if (ret) {
			pr_debug("unwind: access_mem 0x%" PRIx64 " not inside range"
				 " 0x%" PRIx64 "-0x%" PRIx64 "\n",
				addr, start, end);
			return false;
		}
		return true;
	}

	offset  = addr - start;
	*result = *(Dwarf_Word *)&stack->data[offset];
	pr_debug("unwind: access_mem addr 0x%" PRIx64 ", val %lx, offset %d\n",
		 addr, (unsigned long)*result, offset);
	return true;
}

static const Dwfl_Thread_Callbacks callbacks = {
	.next_thread		= next_thread,
	.memory_read		= memory_read,
	.set_initial_registers	= libdw__arch_set_initial_registers,
};

static int
frame_callback(Dwfl_Frame *state, void *arg)
{
	struct unwind_info *ui = arg;
	Dwarf_Addr pc;
	bool isactivation;

	if (!dwfl_frame_pc(state, &pc, NULL)) {
		pr_err("%s", dwfl_errmsg(-1));
		return DWARF_CB_ABORT;
	}

	// report the module before we query for isactivation
	report_module(pc, ui);

	if (!dwfl_frame_pc(state, &pc, &isactivation)) {
		pr_err("%s", dwfl_errmsg(-1));
		return DWARF_CB_ABORT;
	}

	if (!isactivation)
		--pc;

	return entry(pc, ui) || !(--ui->max_stack) ?
	       DWARF_CB_ABORT : DWARF_CB_OK;
}

int unwind__get_entries(unwind_entry_cb_t cb, void *arg,
			struct thread *thread,
			struct perf_sample *data,
			int max_stack)
{
	struct unwind_info *ui, ui_buf = {
		.sample		= data,
		.thread		= thread,
		.machine	= thread->mg->machine,
		.cb		= cb,
		.arg		= arg,
		.max_stack	= max_stack,
	};
	Dwarf_Word ip;
	int err = -EINVAL, i;

	if (!data->user_regs.regs)
		return -EINVAL;

	ui = zalloc(sizeof(ui_buf) + sizeof(ui_buf.entries[0]) * max_stack);
	if (!ui)
		return -ENOMEM;

	*ui = ui_buf;

	ui->dwfl = dwfl_begin(&offline_callbacks);
	if (!ui->dwfl)
		goto out;

	err = perf_reg_value(&ip, &data->user_regs, PERF_REG_IP);
	if (err)
		goto out;

	err = report_module(ip, ui);
	if (err)
		goto out;

	if (!dwfl_attach_state(ui->dwfl, EM_NONE, thread->tid, &callbacks, ui))
		goto out;

	err = dwfl_getthread_frames(ui->dwfl, thread->tid, frame_callback, ui);

	if (err && ui->max_stack != max_stack)
		err = 0;

	/*
	 * Display what we got based on the order setup.
	 */
	for (i = 0; i < ui->idx && !err; i++) {
		int j = i;

		if (callchain_param.order == ORDER_CALLER)
			j = ui->idx - i - 1;

		err = ui->entries[j].ip ? ui->cb(&ui->entries[j], ui->arg) : 0;
	}

 out:
	if (err)
		pr_debug("unwind: failed with '%s'\n", dwfl_errmsg(-1));

	dwfl_end(ui->dwfl);
	free(ui);
	return 0;
}
Commit	Line	Data
5ea84154 JO	1	#include <linux/compiler.h>
	2	#include <elfutils/libdw.h>
	3	#include <elfutils/libdwfl.h>
	4	#include <inttypes.h>
	5	#include <errno.h>
84f5d36f	6	#include "debug.h"
5ea84154 JO	7	#include "unwind.h"
	8	#include "unwind-libdw.h"
	9	#include "machine.h"
	10	#include "thread.h"
d944c4ee	11	#include <linux/types.h>
5ea84154 JO	12	#include "event.h"
5ea84154 JO	13	#include "perf_regs.h"
8bd508b0	14	#include "callchain.h"
9a3993d4	15	#include "util.h"
5ea84154 JO	16
	17	static char *debuginfo_path;
	18
	19	static const Dwfl_Callbacks offline_callbacks = {
	20	.find_debuginfo = dwfl_standard_find_debuginfo,
	21	.debuginfo_path = &debuginfo_path,
	22	.section_address = dwfl_offline_section_address,
	23	};
	24
	25	static int __report_module(struct addr_location *al, u64 ip,
	26	struct unwind_info *ui)
	27	{
	28	Dwfl_Module *mod;
	29	struct dso *dso = NULL;
	30
bb871a9c	31	thread__find_addr_location(ui->thread,
5ea84154 JO	32	PERF_RECORD_MISC_USER,
	33	MAP__FUNCTION, ip, al);
	34
	35	if (al->map)
	36	dso = al->map->dso;
	37
	38	if (!dso)
	39	return 0;
	40
	41	mod = dwfl_addrmodule(ui->dwfl, ip);
2538b9e2 MW	42	if (mod) {
	43	Dwarf_Addr s;
	44
	45	dwfl_module_info(mod, NULL, &s, NULL, NULL, NULL, NULL, NULL);
	46	if (s != al->map->start)
	47	mod = 0;
	48	}
	49
5ea84154 JO	50	if (!mod)
	51	mod = dwfl_report_elf(ui->dwfl, dso->short_name,
	52	dso->long_name, -1, al->map->start,
	53	false);
	54
	55	return mod && dwfl_addrmodule(ui->dwfl, ip) == mod ? 0 : -1;
	56	}
	57
	58	static int report_module(u64 ip, struct unwind_info *ui)
	59	{
	60	struct addr_location al;
	61
	62	return __report_module(&al, ip, ui);
	63	}
	64
8bd508b0 JO	65	/*
	66	* Store all entries within entries array,
	67	* we will process it after we finish unwind.
	68	*/
5ea84154 JO	69	static int entry(u64 ip, struct unwind_info *ui)
	70
	71	{
8bd508b0	72	struct unwind_entry *e = &ui->entries[ui->idx++];
5ea84154 JO	73	struct addr_location al;
	74
	75	if (__report_module(&al, ip, ui))
	76	return -1;
	77
67540759	78	e->ip = al.addr;
8bd508b0 JO	79	e->map = al.map;
8bd508b0 JO	80	e->sym = al.sym;
5ea84154 JO	81
	82	pr_debug("unwind: %s:ip = 0x%" PRIx64 " (0x%" PRIx64 ")\n",
	83	al.sym ? al.sym->name : "''",
	84	ip,
	85	al.map ? al.map->map_ip(al.map, ip) : (u64) 0);
8bd508b0	86	return 0;
5ea84154 JO	87	}
	88
	89	static pid_t next_thread(Dwfl dwfl, void arg, void **thread_argp)
	90	{
	91	/* We want only single thread to be processed. */
	92	if (*thread_argp != NULL)
	93	return 0;
	94
	95	*thread_argp = arg;
	96	return dwfl_pid(dwfl);
	97	}
	98
	99	static int access_dso_mem(struct unwind_info *ui, Dwarf_Addr addr,
	100	Dwarf_Word *data)
	101	{
	102	struct addr_location al;
	103	ssize_t size;
	104
bb871a9c	105	thread__find_addr_map(ui->thread, PERF_RECORD_MISC_USER,
5ea84154	106	MAP__FUNCTION, addr, &al);
0ba98149 JO	107	if (!al.map) {
	108	/*
	109	* We've seen cases (softice) where DWARF unwinder went
	110	* through non executable mmaps, which we need to lookup
	111	* in MAP__VARIABLE tree.
	112	*/
	113	thread__find_addr_map(ui->thread, PERF_RECORD_MISC_USER,
	114	MAP__VARIABLE, addr, &al);
	115	}
	116
5ea84154 JO	117	if (!al.map) {
	118	pr_debug("unwind: no map for %lx\n", (unsigned long)addr);
	119	return -1;
	120	}
	121
	122	if (!al.map->dso)
	123	return -1;
	124
	125	size = dso__data_read_addr(al.map->dso, al.map, ui->machine,
	126	addr, (u8 ) data, sizeof(data));
	127
	128	return !(size == sizeof(*data));
	129	}
	130
	131	static bool memory_read(Dwfl dwfl __maybe_unused, Dwarf_Addr addr, Dwarf_Word result,
	132	void *arg)
	133	{
	134	struct unwind_info *ui = arg;
	135	struct stack_dump *stack = &ui->sample->user_stack;
	136	u64 start, end;
	137	int offset;
	138	int ret;
	139
	140	ret = perf_reg_value(&start, &ui->sample->user_regs, PERF_REG_SP);
	141	if (ret)
	142	return false;
	143
	144	end = start + stack->size;
	145
	146	/* Check overflow. */
	147	if (addr + sizeof(Dwarf_Word) < addr)
	148	return false;
	149
	150	if (addr < start \|\| addr + sizeof(Dwarf_Word) > end) {
	151	ret = access_dso_mem(ui, addr, result);
	152	if (ret) {
	153	pr_debug("unwind: access_mem 0x%" PRIx64 " not inside range"
	154	" 0x%" PRIx64 "-0x%" PRIx64 "\n",
	155	addr, start, end);
	156	return false;
	157	}
	158	return true;
	159	}
	160
	161	offset = addr - start;
	162	result = (Dwarf_Word *)&stack->data[offset];
	163	pr_debug("unwind: access_mem addr 0x%" PRIx64 ", val %lx, offset %d\n",
	164	addr, (unsigned long)*result, offset);
	165	return true;
	166	}
	167
	168	static const Dwfl_Thread_Callbacks callbacks = {
	169	.next_thread = next_thread,
	170	.memory_read = memory_read,
	171	.set_initial_registers = libdw__arch_set_initial_registers,
	172	};
	173
	174	static int
	175	frame_callback(Dwfl_Frame state, void arg)
	176	{
	177	struct unwind_info *ui = arg;
	178	Dwarf_Addr pc;
1982ad48	179	bool isactivation;
5ea84154	180
9126cbba MW	181	if (!dwfl_frame_pc(state, &pc, NULL)) {
	182	pr_err("%s", dwfl_errmsg(-1));
	183	return DWARF_CB_ABORT;
	184	}
	185
	186	// report the module before we query for isactivation
	187	report_module(pc, ui);
	188
1982ad48	189	if (!dwfl_frame_pc(state, &pc, &isactivation)) {
5ea84154 JO	190	pr_err("%s", dwfl_errmsg(-1));
	191	return DWARF_CB_ABORT;
	192	}
	193
1982ad48 MW	194	if (!isactivation)
	195	--pc;
	196
5ea84154 JO	197	return entry(pc, ui) \|\| !(--ui->max_stack) ?
	198	DWARF_CB_ABORT : DWARF_CB_OK;
	199	}
	200
	201	int unwind__get_entries(unwind_entry_cb_t cb, void *arg,
dd8c17a5	202	struct thread *thread,
5ea84154 JO	203	struct perf_sample *data,
	204	int max_stack)
	205	{
8bd508b0	206	struct unwind_info *ui, ui_buf = {
5ea84154 JO	207	.sample = data,
5ea84154 JO	208	.thread = thread,
dd8c17a5	209	.machine = thread->mg->machine,
5ea84154 JO	210	.cb = cb,
	211	.arg = arg,
	212	.max_stack = max_stack,
	213	};
	214	Dwarf_Word ip;
8bd508b0	215	int err = -EINVAL, i;
5ea84154 JO	216
	217	if (!data->user_regs.regs)
	218	return -EINVAL;
	219
8bd508b0 JO	220	ui = zalloc(sizeof(ui_buf) + sizeof(ui_buf.entries[0]) * max_stack);
	221	if (!ui)
	222	return -ENOMEM;
	223
	224	*ui = ui_buf;
	225
	226	ui->dwfl = dwfl_begin(&offline_callbacks);
	227	if (!ui->dwfl)
5ea84154 JO	228	goto out;
	229
	230	err = perf_reg_value(&ip, &data->user_regs, PERF_REG_IP);
	231	if (err)
	232	goto out;
	233
8bd508b0	234	err = report_module(ip, ui);
5ea84154 JO	235	if (err)
	236	goto out;
	237
8bd508b0	238	if (!dwfl_attach_state(ui->dwfl, EM_NONE, thread->tid, &callbacks, ui))
5ea84154 JO	239	goto out;
5ea84154 JO	240
8bd508b0	241	err = dwfl_getthread_frames(ui->dwfl, thread->tid, frame_callback, ui);
5ea84154	242
5ea0416f	243	if (err && ui->max_stack != max_stack)
5ea84154 JO	244	err = 0;
5ea84154 JO	245
8bd508b0 JO	246	/*
	247	* Display what we got based on the order setup.
	248	*/
	249	for (i = 0; i < ui->idx && !err; i++) {
	250	int j = i;
	251
	252	if (callchain_param.order == ORDER_CALLER)
	253	j = ui->idx - i - 1;
	254
	255	err = ui->entries[j].ip ? ui->cb(&ui->entries[j], ui->arg) : 0;
	256	}
	257
5ea84154 JO	258	out:
	259	if (err)
	260	pr_debug("unwind: failed with '%s'\n", dwfl_errmsg(-1));
	261
8bd508b0 JO	262	dwfl_end(ui->dwfl);
8bd508b0 JO	263	free(ui);
5ea84154 JO	264	return 0;
5ea84154 JO	265	}