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// SPDX-License-Identifier: GPL-2.0#include <errno.h>#include <linux/kconfig.h>#include <linux/kernel.h>#include <linux/rbtree.h>#include <linux/types.h>#include <inttypes.h>#include <stdlib.h>#include <unistd.h>#include <stdio.h>#include <string.h>#include <sys/param.h>#include <sys/utsname.h>#include <perf/cpumap.h>#include <perf/evlist.h>#include <perf/mmap.h> #include "debug.h"#include "dso.h"#include "env.h"#include "parse-events.h"#include "evlist.h"#include "evsel.h"#include "thread_map.h"#include "machine.h"#include "map.h"#include "symbol.h"#include "event.h"#include "record.h"#include "util/mmap.h"#include "util/string2.h"#include "util/synthetic-events.h"#include "util/util.h"#include "thread.h" #include "tests.h" #include <linux/ctype.h> #define BUFSZ	1024#define READLEN	128 struct tested_section {	struct rb_node rb_node;	u64 addr;	char path[PATH_MAX];}; static bool tested_code_insert_or_exists(const char *path, u64 addr,					 struct rb_root *tested_sections){	struct rb_node **node = &tested_sections->rb_node;	struct rb_node *parent = NULL;	struct tested_section *data; 	while (*node) {		int cmp; 		parent = *node;		data = rb_entry(*node, struct tested_section, rb_node);		cmp = strcmp(path, data->path);		if (!cmp) {			if (addr < data->addr)				cmp = -1;			else if (addr > data->addr)				cmp = 1;			else				return true; /* already tested */		} 		if (cmp < 0)			node = &(*node)->rb_left;		else			node = &(*node)->rb_right;	} 	data = zalloc(sizeof(*data));	if (!data)		return true; 	data->addr = addr;	strlcpy(data->path, path, sizeof(data->path));	rb_link_node(&data->rb_node, parent, node);	rb_insert_color(&data->rb_node, tested_sections);	return false;} static void tested_sections__free(struct rb_root *root){	while (!RB_EMPTY_ROOT(root)) {		struct rb_node *node = rb_first(root);		struct tested_section *ts = rb_entry(node,						     struct tested_section,						     rb_node); 		rb_erase(node, root);		free(ts);	}} static size_t read_objdump_chunk(const char **line, unsigned char **buf,				 size_t *buf_len){	size_t bytes_read = 0;	unsigned char *chunk_start = *buf; 	/* Read bytes */	while (*buf_len > 0) {		char c1, c2; 		/* Get 2 hex digits */		c1 = *(*line)++;		if (!isxdigit(c1))			break;		c2 = *(*line)++;		if (!isxdigit(c2))			break; 		/* Store byte and advance buf */		**buf = (hex(c1) << 4) | hex(c2);		(*buf)++;		(*buf_len)--;		bytes_read++; 		/* End of chunk? */		if (isspace(**line))			break;	} 	/*	 * objdump will display raw insn as LE if code endian	 * is LE and bytes_per_chunk > 1. In that case reverse	 * the chunk we just read.	 *	 * see disassemble_bytes() at binutils/objdump.c for details	 * how objdump chooses display endian)	 */	if (bytes_read > 1 && !host_is_bigendian()) {		unsigned char *chunk_end = chunk_start + bytes_read - 1;		unsigned char tmp; 		while (chunk_start < chunk_end) {			tmp = *chunk_start;			*chunk_start = *chunk_end;			*chunk_end = tmp;			chunk_start++;			chunk_end--;		}	} 	return bytes_read;} static size_t read_objdump_line(const char *line, unsigned char *buf,				size_t buf_len){	const char *p;	size_t ret, bytes_read = 0; 	/* Skip to a colon */	p = strchr(line, ':');	if (!p)		return 0;	p++; 	/* Skip initial spaces */	while (*p) {		if (!isspace(*p))			break;		p++;	} 	do {		ret = read_objdump_chunk(&p, &buf, &buf_len);		bytes_read += ret;		p++;	} while (ret > 0); 	/* return number of successfully read bytes */	return bytes_read;} static int read_objdump_output(FILE *f, void *buf, size_t *len, u64 start_addr){	char *line = NULL;	size_t line_len, off_last = 0;	ssize_t ret;	int err = 0;	u64 addr, last_addr = start_addr; 	while (off_last < *len) {		size_t off, read_bytes, written_bytes;		unsigned char tmp[BUFSZ]; 		ret = getline(&line, &line_len, f);		if (feof(f))			break;		if (ret < 0) {			pr_debug("getline failed\n");			err = -1;			break;		} 		/* read objdump data into temporary buffer */		read_bytes = read_objdump_line(line, tmp, sizeof(tmp));		if (!read_bytes)			continue; 		if (sscanf(line, "%"PRIx64, &addr) != 1)			continue;		if (addr < last_addr) {			pr_debug("addr going backwards, read beyond section?\n");			break;		}		last_addr = addr; 		/* copy it from temporary buffer to 'buf' according		 * to address on current objdump line */		off = addr - start_addr;		if (off >= *len)			break;		written_bytes = MIN(read_bytes, *len - off);		memcpy(buf + off, tmp, written_bytes);		off_last = off + written_bytes;	} 	/* len returns number of bytes that could not be read */	*len -= off_last; 	free(line); 	return err;} /* * Only gets GNU objdump version. Returns 0 for llvm-objdump. */static int objdump_version(void){	size_t line_len;	char cmd[PATH_MAX * 2];	char *line = NULL;	const char *fmt;	FILE *f;	int ret; 	int version_tmp, version_num = 0;	char *version = 0, *token; 	fmt = "%s --version";	ret = snprintf(cmd, sizeof(cmd), fmt, test_objdump_path);	if (ret <= 0 || (size_t)ret >= sizeof(cmd))		return -1;	/* Ignore objdump errors */	strcat(cmd, " 2>/dev/null");	f = popen(cmd, "r");	if (!f) {		pr_debug("popen failed\n");		return -1;	}	/* Get first line of objdump --version output */	ret = getline(&line, &line_len, f);	pclose(f);	if (ret < 0) {		pr_debug("getline failed\n");		return -1;	} 	token = strsep(&line, " ");	if (token != NULL && !strcmp(token, "GNU")) {		// version is last part of first line of objdump --version output.		while ((token = strsep(&line, " ")))			version = token; 		// Convert version into a format we can compare with		token = strsep(&version, ".");		version_num = atoi(token);		if (version_num)			version_num *= 10000; 		token = strsep(&version, ".");		version_tmp = atoi(token);		if (token)			version_num += version_tmp * 100; 		token = strsep(&version, ".");		version_tmp = atoi(token);		if (token)			version_num += version_tmp;	} 	return version_num;} static int read_via_objdump(const char *filename, u64 addr, void *buf,			    size_t len){	u64 stop_address = addr + len;	struct utsname uname_buf;	char cmd[PATH_MAX * 2];	const char *fmt;	FILE *f;	int ret; 	ret = uname(&uname_buf);	if (ret) {		pr_debug("uname failed\n");		return -1;	} 	if (!strncmp(uname_buf.machine, "riscv", 5)) {		int version = objdump_version(); 		/* Default to this workaround if version parsing fails */		if (version < 0 || version > 24100) {			/*			 * Starting at riscv objdump version 2.41, dumping in			 * the middle of an instruction is not supported. riscv			 * instructions are aligned along 2-byte intervals and			 * can be either 2-bytes or 4-bytes. This makes it			 * possible that the stop-address lands in the middle of			 * a 4-byte instruction. Increase the stop_address by			 * two to ensure an instruction is not cut in half, but			 * leave the len as-is so only the expected number of			 * bytes are collected.			 */			stop_address += 2;		}	} 	fmt = "%s -z -d --start-address=0x%"PRIx64" --stop-address=0x%"PRIx64" %s";	ret = snprintf(cmd, sizeof(cmd), fmt, test_objdump_path, addr, stop_address,		       filename);	if (ret <= 0 || (size_t)ret >= sizeof(cmd))		return -1; 	pr_debug("Objdump command is: %s\n", cmd); 	/* Ignore objdump errors */	strcat(cmd, " 2>/dev/null"); 	f = popen(cmd, "r");	if (!f) {		pr_debug("popen failed\n");		return -1;	} 	ret = read_objdump_output(f, buf, &len, addr);	if (len) {		pr_debug("objdump read too few bytes: %zd\n", len);		if (!ret)			ret = len;	} 	pclose(f); 	return ret;} static void dump_buf(unsigned char *buf, size_t len){	size_t i; 	for (i = 0; i < len; i++) {		pr_debug("0x%02x ", buf[i]);		if (i % 16 == 15)			pr_debug("\n");	}	pr_debug("\n");} static int read_object_code(u64 addr, size_t len, u8 cpumode,			    struct thread *thread,			    struct rb_root *tested_sections){	struct addr_location al;	unsigned char buf1[BUFSZ] = {0};	unsigned char buf2[BUFSZ] = {0};	size_t ret_len;	u64 objdump_addr;	u64 skip_addr;	const char *objdump_name;	char decomp_name[KMOD_DECOMP_LEN];	bool decomp = false;	int ret, err = 0;	struct dso *dso; 	pr_debug("Reading object code for memory address: %#"PRIx64"\n", addr); 	addr_location__init(&al);	if (!thread__find_map(thread, cpumode, addr, &al) || !map__dso(al.map)) {		if (cpumode == PERF_RECORD_MISC_HYPERVISOR) {			pr_debug("Hypervisor address can not be resolved - skipping\n");			goto out;		} 		pr_debug("thread__find_map failed\n");		err = -1;		goto out;	}	dso = map__dso(al.map);	pr_debug("File is: %s\n", dso__long_name(dso)); 	if (dso__symtab_type(dso) == DSO_BINARY_TYPE__KALLSYMS && !dso__is_kcore(dso)) {		pr_debug("Unexpected kernel address - skipping\n");		goto out;	} 	/*	 * Don't retest the same addresses. objdump struggles with kcore - try	 * each map only once even if the address is different.	 */	skip_addr = dso__is_kcore(dso) ? map__start(al.map) : al.addr;	if (tested_code_insert_or_exists(dso__long_name(dso), skip_addr,					 tested_sections)) {		pr_debug("Already tested %s @ %#"PRIx64" - skipping\n",			 dso__long_name(dso), skip_addr);		goto out;	} 	pr_debug("On file address is: %#"PRIx64"\n", al.addr); 	if (len > BUFSZ)		len = BUFSZ; 	/* Do not go off the map */	if (addr + len > map__end(al.map))		len = map__end(al.map) - addr; 	/*	 * Some architectures (ex: powerpc) have stubs (trampolines) in kernel	 * modules to manage long jumps. Check if the ip offset falls in stubs	 * sections for kernel modules. And skip module address after text end	 */	if (dso__is_kmod(dso) && al.addr > dso__text_end(dso)) {		pr_debug("skipping the module address %#"PRIx64" after text end\n", al.addr);		goto out;	} 	/* Read the object code using perf */	ret_len = dso__data_read_offset(dso, maps__machine(thread__maps(thread)),					al.addr, buf1, len);	if (ret_len != len) {		pr_debug("dso__data_read_offset failed\n");		err = -1;		goto out;	} 	/*	 * Converting addresses for use by objdump requires more information.	 * map__load() does that.  See map__rip_2objdump() for details.	 */	if (map__load(al.map)) {		err = -1;		goto out;	} 	objdump_name = dso__long_name(dso);	if (dso__needs_decompress(dso)) {		if (dso__decompress_kmodule_path(dso, objdump_name,						 decomp_name,						 sizeof(decomp_name)) < 0) {			pr_debug("decompression failed\n");			err = -1;			goto out;		} 		decomp = true;		objdump_name = decomp_name;	} 	/* Read the object code using objdump */	objdump_addr = map__rip_2objdump(al.map, al.addr);	ret = read_via_objdump(objdump_name, objdump_addr, buf2, len); 	if (decomp)		unlink(objdump_name); 	if (ret > 0) {		/*		 * The kernel maps are inaccurate - assume objdump is right in		 * that case.		 */		if (cpumode == PERF_RECORD_MISC_KERNEL ||		    cpumode == PERF_RECORD_MISC_GUEST_KERNEL) {			len -= ret;			if (len) {				pr_debug("Reducing len to %zu\n", len);			} else if (dso__is_kcore(dso)) {				/*				 * objdump cannot handle very large segments				 * that may be found in kcore.				 */				pr_debug("objdump failed for kcore");				pr_debug(" - skipping\n");			} else {				err = -1;			}			goto out;		}

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