// SPDX-License-Identifier: GPL-2.0-only/* * Copyright 2013-2015, Michael Ellerman, IBM Corp. */ #define _GNU_SOURCE	/* For CPU_ZERO etc. */ #include <elf.h>#include <errno.h>#include <fcntl.h>#include <link.h>#include <sched.h>#include <signal.h>#include <stdio.h>#include <stdlib.h>#include <string.h>#include <sys/ioctl.h>#include <sys/stat.h>#include <sys/sysinfo.h>#include <sys/types.h>#include <sys/utsname.h>#include <unistd.h>#include <asm/unistd.h>#include <linux/limits.h> #include "utils.h" static char auxv[4096]; int read_auxv(char *buf, ssize_t buf_size){	ssize_t num;	int rc, fd; 	fd = open("/proc/self/auxv", O_RDONLY);	if (fd == -1) {		perror("open");		return -errno;	} 	num = read(fd, buf, buf_size);	if (num < 0) {		perror("read");		rc = -EIO;		goto out;	} 	if (num > buf_size) {		printf("overflowed auxv buffer\n");		rc = -EOVERFLOW;		goto out;	} 	rc = 0;out:	close(fd);	return rc;} void *find_auxv_entry(int type, char *auxv){	ElfW(auxv_t) *p; 	p = (ElfW(auxv_t) *)auxv; 	while (p->a_type != AT_NULL) {		if (p->a_type == type)			return p; 		p++;	} 	return NULL;} void *get_auxv_entry(int type){	ElfW(auxv_t) *p; 	if (read_auxv(auxv, sizeof(auxv)))		return NULL; 	p = find_auxv_entry(type, auxv);	if (p)		return (void *)p->a_un.a_val; 	return NULL;} int pick_online_cpu(void){	int ncpus, cpu = -1;	cpu_set_t *mask;	size_t size; 	ncpus = get_nprocs_conf();	size = CPU_ALLOC_SIZE(ncpus);	mask = CPU_ALLOC(ncpus);	if (!mask) {		perror("malloc");		return -1;	} 	CPU_ZERO_S(size, mask); 	if (sched_getaffinity(0, size, mask)) {		perror("sched_getaffinity");		goto done;	} 	/* We prefer a primary thread, but skip 0 */	for (cpu = 8; cpu < ncpus; cpu += 8)		if (CPU_ISSET_S(cpu, size, mask))			goto done; 	/* Search for anything, but in reverse */	for (cpu = ncpus - 1; cpu >= 0; cpu--)		if (CPU_ISSET_S(cpu, size, mask))			goto done; 	printf("No cpus in affinity mask?!\n"); done:	CPU_FREE(mask);	return cpu;} bool is_ppc64le(void){	struct utsname uts;	int rc; 	errno = 0;	rc = uname(&uts);	if (rc) {		perror("uname");		return false;	} 	return strcmp(uts.machine, "ppc64le") == 0;} int read_sysfs_file(char *fpath, char *result, size_t result_size){	char path[PATH_MAX] = "/sys/";	int rc = -1, fd; 	strncat(path, fpath, PATH_MAX - strlen(path) - 1); 	if ((fd = open(path, O_RDONLY)) < 0)		return rc; 	rc = read(fd, result, result_size); 	close(fd); 	if (rc < 0)		return rc; 	return 0;} int read_debugfs_file(char *debugfs_file, int *result){	int rc = -1, fd;	char path[PATH_MAX];	char value[16]; 	strcpy(path, "/sys/kernel/debug/");	strncat(path, debugfs_file, PATH_MAX - strlen(path) - 1); 	if ((fd = open(path, O_RDONLY)) < 0)		return rc; 	if ((rc = read(fd, value, sizeof(value))) < 0)		return rc; 	value[15] = 0;	*result = atoi(value);	close(fd); 	return 0;} int write_debugfs_file(char *debugfs_file, int result){	int rc = -1, fd;	char path[PATH_MAX];	char value[16]; 	strcpy(path, "/sys/kernel/debug/");	strncat(path, debugfs_file, PATH_MAX - strlen(path) - 1); 	if ((fd = open(path, O_WRONLY)) < 0)		return rc; 	snprintf(value, 16, "%d", result); 	if ((rc = write(fd, value, strlen(value))) < 0)		return rc; 	close(fd); 	return 0;} static long perf_event_open(struct perf_event_attr *hw_event, pid_t pid,		int cpu, int group_fd, unsigned long flags){	return syscall(__NR_perf_event_open, hw_event, pid, cpu,		      group_fd, flags);} static void perf_event_attr_init(struct perf_event_attr *event_attr,					unsigned int type,					unsigned long config){	memset(event_attr, 0, sizeof(*event_attr)); 	event_attr->type = type;	event_attr->size = sizeof(struct perf_event_attr);	event_attr->config = config;	event_attr->read_format = PERF_FORMAT_GROUP;	event_attr->disabled = 1;	event_attr->exclude_kernel = 1;	event_attr->exclude_hv = 1;	event_attr->exclude_guest = 1;} int perf_event_open_counter(unsigned int type,			    unsigned long config, int group_fd){	int fd;	struct perf_event_attr event_attr; 	perf_event_attr_init(&event_attr, type, config); 	fd = perf_event_open(&event_attr, 0, -1, group_fd, 0); 	if (fd < 0)		perror("perf_event_open() failed"); 	return fd;} int perf_event_enable(int fd){	if (ioctl(fd, PERF_EVENT_IOC_ENABLE, PERF_IOC_FLAG_GROUP) == -1) {		perror("error while enabling perf events");		return -1;	} 	return 0;} int perf_event_disable(int fd){	if (ioctl(fd, PERF_EVENT_IOC_DISABLE, PERF_IOC_FLAG_GROUP) == -1) {		perror("error disabling perf events");		return -1;	} 	return 0;} int perf_event_reset(int fd){	if (ioctl(fd, PERF_EVENT_IOC_RESET, PERF_IOC_FLAG_GROUP) == -1) {		perror("error resetting perf events");		return -1;	} 	return 0;} static void sigill_handler(int signr, siginfo_t *info, void *unused){	static int warned = 0;	ucontext_t *ctx = (ucontext_t *)unused;	unsigned long *pc = &UCONTEXT_NIA(ctx); 	/* mtspr 3,RS to check for move to DSCR below */	if ((*((unsigned int *)*pc) & 0xfc1fffff) == 0x7c0303a6) {		if (!warned++)			printf("WARNING: Skipping over dscr setup. Consider running 'ppc64_cpu --dscr=1' manually.\n");		*pc += 4;	} else {		printf("SIGILL at %p\n", pc);		abort();	}} void set_dscr(unsigned long val){	static int init = 0;	struct sigaction sa; 	if (!init) {		memset(&sa, 0, sizeof(sa));		sa.sa_sigaction = sigill_handler;		sa.sa_flags = SA_SIGINFO;		if (sigaction(SIGILL, &sa, NULL))			perror("sigill_handler");		init = 1;	} 	asm volatile("mtspr %1,%0" : : "r" (val), "i" (SPRN_DSCR));} int using_hash_mmu(bool *using_hash){	char line[128];	FILE *f;	int rc; 	f = fopen("/proc/cpuinfo", "r");	FAIL_IF(!f); 	rc = 0;	while (fgets(line, sizeof(line), f) != NULL) {		if (strcmp(line, "MMU		: Hash\n") == 0) {			*using_hash = true;			goto out;		} 		if (strcmp(line, "MMU		: Radix\n") == 0) {			*using_hash = false;			goto out;		}	} 	rc = -1;out:	fclose(f);	return rc;}