// SPDX-License-Identifier: GPL-2.0
#include "cpumap.h"
#include "dwarf-regs.h"
#include "debug.h"
#include "env.h"
#include "util/header.h"
#include "util/rwsem.h"
#include <linux/compiler.h>
#include <linux/kernel.h>
#include <linux/ctype.h>
#include <linux/rbtree.h>
#include <linux/string.h>
#include <linux/zalloc.h>
#include "cgroup.h"
#include <errno.h>
#include <sys/utsname.h>
#include <stdlib.h>
#include <string.h>
#include "pmu.h"
#include "pmus.h"
#include "strbuf.h"
#include "trace/beauty/beauty.h"

#ifdef HAVE_LIBBPF_SUPPORT
#include "bpf-event.h"
#include "bpf-utils.h"
#include <bpf/libbpf.h>

bool perf_env__insert_bpf_prog_info(struct perf_env *env,
                                    struct bpf_prog_info_node *info_node)
{
        bool ret;

        down_write(&env->bpf_progs.lock);
        ret = __perf_env__insert_bpf_prog_info(env, info_node);
        up_write(&env->bpf_progs.lock);

        return ret;
}

bool __perf_env__insert_bpf_prog_info(struct perf_env *env, struct bpf_prog_info_node *info_node)
{
        __u32 prog_id = info_node->info_linear->info.id;
        struct bpf_prog_info_node *node;
        struct rb_node *parent = NULL;
        struct rb_node **p;

        p = &env->bpf_progs.infos.rb_node;

        while (*p != NULL) {
                parent = *p;
                node = rb_entry(parent, struct bpf_prog_info_node, rb_node);
                if (prog_id < node->info_linear->info.id) {
                        p = &(*p)->rb_left;
                } else if (prog_id > node->info_linear->info.id) {
                        p = &(*p)->rb_right;
                } else {
                        pr_debug("duplicated bpf prog info %u\n", prog_id);
                        return false;
                }
        }

        rb_link_node(&info_node->rb_node, parent, p);
        rb_insert_color(&info_node->rb_node, &env->bpf_progs.infos);
        env->bpf_progs.infos_cnt++;
        return true;
}

struct bpf_prog_info_node *perf_env__find_bpf_prog_info(struct perf_env *env,
                                                        __u32 prog_id)
{
        struct bpf_prog_info_node *node = NULL;
        struct rb_node *n;

        down_read(&env->bpf_progs.lock);
        n = env->bpf_progs.infos.rb_node;

        while (n) {
                node = rb_entry(n, struct bpf_prog_info_node, rb_node);
                if (prog_id < node->info_linear->info.id)
                        n = n->rb_left;
                else if (prog_id > node->info_linear->info.id)
                        n = n->rb_right;
                else
                        goto out;
        }
        node = NULL;

out:
        up_read(&env->bpf_progs.lock);
        return node;
}

void perf_env__iterate_bpf_prog_info(struct perf_env *env,
                                     void (*cb)(struct bpf_prog_info_node *node,
                                                void *data),
                                     void *data)
{
        struct rb_node *first;

        down_read(&env->bpf_progs.lock);
        first = rb_first(&env->bpf_progs.infos);
        for (struct rb_node *node = first; node != NULL; node = rb_next(node))
                (*cb)(rb_entry(node, struct bpf_prog_info_node, rb_node), data);
        up_read(&env->bpf_progs.lock);
}

bool perf_env__insert_btf(struct perf_env *env, struct btf_node *btf_node)
{
        bool ret;

        down_write(&env->bpf_progs.lock);
        ret = __perf_env__insert_btf(env, btf_node);
        up_write(&env->bpf_progs.lock);
        return ret;
}

bool __perf_env__insert_btf(struct perf_env *env, struct btf_node *btf_node)
{
        struct rb_node *parent = NULL;
        __u32 btf_id = btf_node->id;
        struct btf_node *node;
        struct rb_node **p;

        p = &env->bpf_progs.btfs.rb_node;

        while (*p != NULL) {
                parent = *p;
                node = rb_entry(parent, struct btf_node, rb_node);
                if (btf_id < node->id) {
                        p = &(*p)->rb_left;
                } else if (btf_id > node->id) {
                        p = &(*p)->rb_right;
                } else {
                        pr_debug("duplicated btf %u\n", btf_id);
                        return false;
                }
        }

        rb_link_node(&btf_node->rb_node, parent, p);
        rb_insert_color(&btf_node->rb_node, &env->bpf_progs.btfs);
        env->bpf_progs.btfs_cnt++;
        return true;
}

struct btf_node *perf_env__find_btf(struct perf_env *env, __u32 btf_id)
{
        struct btf_node *res;

        down_read(&env->bpf_progs.lock);
        res = __perf_env__find_btf(env, btf_id);
        up_read(&env->bpf_progs.lock);
        return res;
}

struct btf_node *__perf_env__find_btf(struct perf_env *env, __u32 btf_id)
{
        struct btf_node *node = NULL;
        struct rb_node *n;

        n = env->bpf_progs.btfs.rb_node;

        while (n) {
                node = rb_entry(n, struct btf_node, rb_node);
                if (btf_id < node->id)
                        n = n->rb_left;
                else if (btf_id > node->id)
                        n = n->rb_right;
                else
                        return node;
        }
        return NULL;
}

/* purge data in bpf_progs.infos tree */
static void perf_env__purge_bpf(struct perf_env *env)
{
        struct rb_root *root;
        struct rb_node *next;

        down_write(&env->bpf_progs.lock);

        root = &env->bpf_progs.infos;
        next = rb_first(root);

        while (next) {
                struct bpf_prog_info_node *node;

                node = rb_entry(next, struct bpf_prog_info_node, rb_node);
                next = rb_next(&node->rb_node);
                rb_erase(&node->rb_node, root);
                zfree(&node->info_linear);
                bpf_metadata_free(node->metadata);
                free(node);
        }

        env->bpf_progs.infos_cnt = 0;

        root = &env->bpf_progs.btfs;
        next = rb_first(root);

        while (next) {
                struct btf_node *node;

                node = rb_entry(next, struct btf_node, rb_node);
                next = rb_next(&node->rb_node);
                rb_erase(&node->rb_node, root);
                free(node);
        }

        env->bpf_progs.btfs_cnt = 0;

        up_write(&env->bpf_progs.lock);
}
#else // HAVE_LIBBPF_SUPPORT
static void perf_env__purge_bpf(struct perf_env *env __maybe_unused)
{
}
#endif // HAVE_LIBBPF_SUPPORT

void free_cpu_domain_info(struct cpu_domain_map **cd_map, u32 schedstat_version, u32 nr)
{
        if (!cd_map)
                return;

        for (u32 i = 0; i < nr; i++) {
                if (!cd_map[i])
                        continue;

                for (u32 j = 0; j < cd_map[i]->nr_domains; j++) {
                        struct domain_info *d_info = cd_map[i]->domains[j];

                        if (!d_info)
                                continue;

                        if (schedstat_version >= 17)
                                zfree(&d_info->dname);

                        zfree(&d_info->cpumask);
                        zfree(&d_info->cpulist);
                        zfree(&d_info);
                }
                zfree(&cd_map[i]->domains);
                zfree(&cd_map[i]);
        }
        zfree(&cd_map);
}

void perf_env__exit(struct perf_env *env)
{
        int i, j;

        mutex_destroy(&env->lock);

        perf_env__purge_bpf(env);
        perf_env__purge_cgroups(env);
        zfree(&env->hostname);
        zfree(&env->os_release);
        zfree(&env->version);
        zfree(&env->arch);
        zfree(&env->cpu_desc);
        zfree(&env->cpuid);
        zfree(&env->cmdline);
        zfree(&env->cmdline_argv);
        zfree(&env->sibling_dies);
        zfree(&env->sibling_cores);
        zfree(&env->sibling_threads);
        zfree(&env->pmu_mappings);
        zfree(&env->cpu);
        for (i = 0; i < env->nr_cpu_pmu_caps; i++)
                zfree(&env->cpu_pmu_caps[i]);
        zfree(&env->cpu_pmu_caps);
        zfree(&env->numa_map);

        for (i = 0; i < env->nr_numa_nodes; i++)
                perf_cpu_map__put(env->numa_nodes[i].map);
        zfree(&env->numa_nodes);

        for (i = 0; i < env->caches_cnt; i++)
                cpu_cache_level__free(&env->caches[i]);
        zfree(&env->caches);

        for (i = 0; i < env->nr_memory_nodes; i++)
                zfree(&env->memory_nodes[i].set);
        zfree(&env->memory_nodes);

        for (i = 0; i < env->nr_hybrid_nodes; i++) {
                zfree(&env->hybrid_nodes[i].pmu_name);
                zfree(&env->hybrid_nodes[i].cpus);
        }
        zfree(&env->hybrid_nodes);

        for (i = 0; i < env->nr_pmus_with_caps; i++) {
                for (j = 0; j < env->pmu_caps[i].nr_caps; j++)
                        zfree(&env->pmu_caps[i].caps[j]);
                zfree(&env->pmu_caps[i].caps);
                zfree(&env->pmu_caps[i].pmu_name);
        }
        zfree(&env->pmu_caps);
        free_cpu_domain_info(env->cpu_domain, env->schedstat_version, env->nr_cpus_avail);
}

void perf_env__init(struct perf_env *env)
{
        memset(env, 0, sizeof(*env));
#ifdef HAVE_LIBBPF_SUPPORT
        env->bpf_progs.infos = RB_ROOT;
        env->bpf_progs.btfs = RB_ROOT;
        init_rwsem(&env->bpf_progs.lock);
#endif
        env->kernel_is_64_bit = -1;
        mutex_init(&env->lock);
}

static void perf_env__init_kernel_mode(struct perf_env *env)
{
        const char *arch = env->arch;

        if (!arch) {
                static struct utsname uts = { .machine[0] = '\0', };

                if (uts.machine[0] == '\0')
                        uname(&uts);
                if (uts.machine[0] != '\0')
                        arch = uts.machine;
        }

        if (arch) {
                if (strstr(arch, "64") || strstr(arch, "s390x"))
                        env->kernel_is_64_bit = 1;
                else
                        env->kernel_is_64_bit = 0;
                return;
        }

        /* Fallback if completely unresolvable (assume host-bitness) */
        env->kernel_is_64_bit = (sizeof(void *) == 8) ? 1 : 0;
}

int perf_env__kernel_is_64_bit(struct perf_env *env)
{
        if (env->kernel_is_64_bit == -1)
                perf_env__init_kernel_mode(env);

        return env->kernel_is_64_bit;
}

bool perf_arch_is_big_endian(const char *arch)
{
        if (!arch)
                return __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__;

        if (str_ends_with(arch, "_be") || !strcmp(arch, "sparc") || !strcmp(arch, "sparc64") ||
            !strcmp(arch, "s390") || !strcmp(arch, "s390x") || !strcmp(arch, "powerpc") ||
            !strcmp(arch, "ppc") || !strcmp(arch, "ppc64") ||
            !strcmp(arch, "mips") || !strcmp(arch, "mips64") || !strcmp(arch, "parisc") ||
            !strcmp(arch, "parisc64") || !strcmp(arch, "m68k") ||
            !strcmp(arch, "armeb") || !strcmp(arch, "mipseb") || !strcmp(arch, "mips64eb"))
                return true;

        return false;
}

const char *perf_env__os_release(struct perf_env *env)
{
        struct utsname uts;
        int ret;
        const char *release;

        if (!env)
                return perf_version_string;

        mutex_lock(&env->lock);
        if (env->os_release) {
                release = env->os_release;
                goto out;
        }

        /*
         * If env->arch is set, this is an offline target environment.
         * If the os_release is not populated in the file, we do not want
         * to poison it with the host's release which would break guest checks.
         */
        if (env->arch) {
                release = NULL;
                goto out;
        }

        /*
         * The os_release is being accessed but wasn't initialized from a data
         * file, assume this is 'live' mode and use the release from uname. If
         * uname or strdup fails then use the current perf tool version.
         */
        ret = uname(&uts);
        env->os_release = strdup(ret < 0 ? perf_version_string : uts.release);
        release = env->os_release ?: perf_version_string;
out:
        mutex_unlock(&env->lock);
        return release;
}

int perf_env__set_cmdline(struct perf_env *env, int argc, const char *argv[])
{
        int i;

        /* do not include NULL termination */
        env->cmdline_argv = calloc(argc, sizeof(char *));
        if (env->cmdline_argv == NULL)
                goto out_enomem;

        /*
         * Must copy argv contents because it gets moved around during option
         * parsing:
         */
        for (i = 0; i < argc ; i++) {
                env->cmdline_argv[i] = argv[i];
                if (env->cmdline_argv[i] == NULL)
                        goto out_free;
        }

        env->nr_cmdline = argc;

        return 0;
out_free:
        zfree(&env->cmdline_argv);
out_enomem:
        return -ENOMEM;
}

int perf_env__read_cpu_topology_map(struct perf_env *env)
{
        int idx, nr_cpus;

        if (env->cpu != NULL)
                return 0;

        if (env->nr_cpus_avail == 0)
                env->nr_cpus_avail = cpu__max_present_cpu().cpu;

        nr_cpus = env->nr_cpus_avail;
        if (nr_cpus == -1)
                return -EINVAL;

        env->cpu = calloc(nr_cpus, sizeof(env->cpu[0]));
        if (env->cpu == NULL)
                return -ENOMEM;

        for (idx = 0; idx < nr_cpus; ++idx) {
                struct perf_cpu cpu = { .cpu = idx };
                int core_id   = cpu__get_core_id(cpu);
                int socket_id = cpu__get_socket_id(cpu);
                int die_id    = cpu__get_die_id(cpu);

                env->cpu[idx].core_id   = core_id >= 0 ? core_id : -1;
                env->cpu[idx].socket_id = socket_id >= 0 ? socket_id : -1;
                env->cpu[idx].die_id    = die_id >= 0 ? die_id : -1;
        }

        env->nr_cpus_avail = nr_cpus;
        return 0;
}

int perf_env__read_pmu_mappings(struct perf_env *env)
{
        struct perf_pmu *pmu = NULL;
        u32 pmu_num = 0;
        struct strbuf sb;

        while ((pmu = perf_pmus__scan(pmu)))
                pmu_num++;

        if (!pmu_num) {
                pr_debug("pmu mappings not available\n");
                return -ENOENT;
        }
        env->nr_pmu_mappings = pmu_num;

        if (strbuf_init(&sb, 128 * pmu_num) < 0)
                return -ENOMEM;

        while ((pmu = perf_pmus__scan(pmu))) {
                if (strbuf_addf(&sb, "%u:%s", pmu->type, pmu->name) < 0)
                        goto error;
                /* include a NULL character at the end */
                if (strbuf_add(&sb, "", 1) < 0)
                        goto error;
        }

        env->pmu_mappings = strbuf_detach(&sb, NULL);

        return 0;

error:
        strbuf_release(&sb);
        return -1;
}

int perf_env__read_cpuid(struct perf_env *env)
{
        char cpuid[128];
        struct perf_cpu cpu = {-1};
        int err = get_cpuid(cpuid, sizeof(cpuid), cpu);

        if (err)
                return err;

        free(env->cpuid);
        env->cpuid = strdup(cpuid);
        if (env->cpuid == NULL)
                return ENOMEM;
        return 0;
}

static int perf_env__read_nr_cpus_avail(struct perf_env *env)
{
        if (env->nr_cpus_avail == 0)
                env->nr_cpus_avail = cpu__max_present_cpu().cpu;

        return env->nr_cpus_avail ? 0 : -ENOENT;
}

static int __perf_env__read_core_pmu_caps(const struct perf_pmu *pmu,
                                          int *nr_caps, char ***caps,
                                          unsigned int *max_branches,
                                          unsigned int *br_cntr_nr,
                                          unsigned int *br_cntr_width)
{
        struct perf_pmu_caps *pcaps = NULL;
        char *ptr, **tmp;
        int ret = 0;

        *nr_caps = 0;
        *caps = NULL;

        if (!pmu->nr_caps)
                return 0;

        *caps = calloc(pmu->nr_caps, sizeof(char *));
        if (!*caps)
                return -ENOMEM;

        tmp = *caps;
        list_for_each_entry(pcaps, &pmu->caps, list) {
                if (asprintf(&ptr, "%s=%s", pcaps->name, pcaps->value) < 0) {
                        ret = -ENOMEM;
                        goto error;
                }

                *tmp++ = ptr;

                if (!strcmp(pcaps->name, "branches"))
                        *max_branches = atoi(pcaps->value);
                else if (!strcmp(pcaps->name, "branch_counter_nr"))
                        *br_cntr_nr = atoi(pcaps->value);
                else if (!strcmp(pcaps->name, "branch_counter_width"))
                        *br_cntr_width = atoi(pcaps->value);
        }
        *nr_caps = pmu->nr_caps;
        return 0;
error:
        while (tmp-- != *caps)
                zfree(tmp);
        zfree(caps);
        *nr_caps = 0;
        return ret;
}

int perf_env__read_core_pmu_caps(struct perf_env *env)
{
        struct pmu_caps *pmu_caps;
        struct perf_pmu *pmu = NULL;
        int nr_pmu, i = 0, j;
        int ret;

        nr_pmu = perf_pmus__num_core_pmus();

        if (!nr_pmu)
                return -ENODEV;

        if (nr_pmu == 1) {
                pmu = perf_pmus__find_core_pmu();
                if (!pmu)
                        return -ENODEV;
                ret = perf_pmu__caps_parse(pmu);
                if (ret < 0)
                        return ret;
                return __perf_env__read_core_pmu_caps(pmu, &env->nr_cpu_pmu_caps,
                                                      &env->cpu_pmu_caps,
                                                      &env->max_branches,
                                                      &env->br_cntr_nr,
                                                      &env->br_cntr_width);
        }

        pmu_caps = calloc(nr_pmu, sizeof(*pmu_caps));
        if (!pmu_caps)
                return -ENOMEM;

        while ((pmu = perf_pmus__scan_core(pmu)) != NULL) {
                if (perf_pmu__caps_parse(pmu) <= 0)
                        continue;
                ret = __perf_env__read_core_pmu_caps(pmu, &pmu_caps[i].nr_caps,
                                                     &pmu_caps[i].caps,
                                                     &pmu_caps[i].max_branches,
                                                     &pmu_caps[i].br_cntr_nr,
                                                     &pmu_caps[i].br_cntr_width);
                if (ret)
                        goto error;

                pmu_caps[i].pmu_name = strdup(pmu->name);
                if (!pmu_caps[i].pmu_name) {
                        ret = -ENOMEM;
                        goto error;
                }
                i++;
        }

        env->nr_pmus_with_caps = nr_pmu;
        env->pmu_caps = pmu_caps;

        return 0;
error:
        for (i = 0; i < nr_pmu; i++) {
                for (j = 0; j < pmu_caps[i].nr_caps; j++)
                        zfree(&pmu_caps[i].caps[j]);
                zfree(&pmu_caps[i].caps);
                zfree(&pmu_caps[i].pmu_name);
        }
        zfree(&pmu_caps);
        return ret;
}

int perf_env__nr_cpus_avail(struct perf_env *env)
{
        return env && !perf_env__read_nr_cpus_avail(env) ? env->nr_cpus_avail : 0;
}

void cpu_cache_level__free(struct cpu_cache_level *cache)
{
        zfree(&cache->type);
        zfree(&cache->map);
        zfree(&cache->size);
}

struct arch_to_e_machine {
        const char *prefix;
        uint16_t e_machine;
};

/*
 * A mapping from an arch prefix string to an ELF machine that can be used in a
 * bsearch. Some arch prefixes are shared an need additional processing as
 * marked next to the architecture. The prefixes handle both perf's architecture
 * naming and those from uname.
 */
static const struct arch_to_e_machine prefix_to_e_machine[] = {
        {"aarch64", EM_AARCH64},
        {"alpha", EM_ALPHA},
        {"arc", EM_ARC},
        {"arm", EM_ARM}, /* Check also for EM_AARCH64. */
        {"avr", EM_AVR},  /* Check also for EM_AVR32. */
        {"bfin", EM_BLACKFIN},
        {"blackfin", EM_BLACKFIN},
        {"cris", EM_CRIS},
        {"csky", EM_CSKY},
        {"hppa", EM_PARISC},
        {"i386", EM_386},
        {"i486", EM_386},
        {"i586", EM_386},
        {"i686", EM_386},
        {"loongarch", EM_LOONGARCH},
        {"m32r", EM_M32R},
        {"m68k", EM_68K},
        {"microblaze", EM_MICROBLAZE},
        {"mips", EM_MIPS},
        {"msp430", EM_MSP430},
        {"parisc", EM_PARISC},
        {"powerpc", EM_PPC}, /* Check also for EM_PPC64. */
        {"ppc", EM_PPC}, /* Check also for EM_PPC64. */
        {"riscv", EM_RISCV},
        {"s390", EM_S390},
        {"sa110", EM_ARM},
        {"sh", EM_SH},
        {"sparc", EM_SPARC}, /* Check also for EM_SPARCV9. */
        {"sun4u", EM_SPARC},
        {"x86", EM_X86_64}, /* Check also for EM_386. */
        {"xtensa", EM_XTENSA},
};

static int compare_prefix(const void *key, const void *element)
{
        const char *search_key = key;
        const struct arch_to_e_machine *map_element = element;
        size_t prefix_len = strlen(map_element->prefix);

        return strncmp(search_key, map_element->prefix, prefix_len);
}

static uint16_t perf_arch_to_e_machine(const char *perf_arch, int is_64_bit)
{
        /* Binary search for a matching prefix. */
        const struct arch_to_e_machine *result;

        if (!perf_arch)
                return EM_HOST;

        result = bsearch(perf_arch,
                         prefix_to_e_machine, ARRAY_SIZE(prefix_to_e_machine),
                         sizeof(prefix_to_e_machine[0]),
                         compare_prefix);

        if (!result) {
                pr_debug("Unknown perf arch for ELF machine mapping: %s\n", perf_arch);
                return EM_NONE;
        }

        /*
         * Handle conflicting prefixes. If the is_64_bit is unknown (-1) then
         * assume 64-bit. We can't use perf_env__kernel_is_64_bit as that
         * depends on the arch string.
         */
        switch (result->e_machine) {
        case EM_ARM:
                return !strcmp(perf_arch, "arm64") || !strcmp(perf_arch, "aarch64")
                        ? EM_AARCH64 : EM_ARM;
        case EM_AVR:
                return !strcmp(perf_arch, "avr32") ? EM_AVR32 : EM_AVR;
        case EM_PPC:
                if (is_64_bit == 1)
                        return EM_PPC64;
                if (is_64_bit == 0)
                        return EM_PPC;
                return strstarts(perf_arch, "ppc64") ? EM_PPC64 : EM_PPC;
        case EM_SPARC:
                if (is_64_bit == 1)
                        return EM_SPARCV9;
                if (is_64_bit == 0)
                        return EM_SPARC;
                return !strcmp(perf_arch, "sparc64") || !strcmp(perf_arch, "sun4u")
                        ? EM_SPARCV9 : EM_SPARC;
        case EM_X86_64:
                if (is_64_bit == 1)
                        return EM_X86_64;
                if (is_64_bit == 0)
                        return EM_386;
                return !strcmp(perf_arch, "x86_64") || !strcmp(perf_arch, "x86")
                        ? EM_X86_64 : EM_386;
        default:
                return result->e_machine;
        }
}

static const char *e_machine_to_perf_arch(uint16_t e_machine)
{
        /*
         * Table for if either the perf arch string differs from uname or there
         * are >1 ELF machine with the prefix.
         */
        static const struct arch_to_e_machine extras[] = {
                {"arm64", EM_AARCH64},
                {"avr32", EM_AVR32},
                {"powerpc", EM_PPC},
                {"powerpc", EM_PPC64},
                {"sparc", EM_SPARCV9},
                {"x86", EM_386},
                {"x86", EM_X86_64},
                {"none", EM_NONE},
        };

        for (size_t i = 0; i < ARRAY_SIZE(extras); i++) {
                if (extras[i].e_machine == e_machine)
                        return extras[i].prefix;
        }

        for (size_t i = 0; i < ARRAY_SIZE(prefix_to_e_machine); i++) {
                if (prefix_to_e_machine[i].e_machine == e_machine)
                        return prefix_to_e_machine[i].prefix;

        }
        return "unknown";
}

uint16_t perf_env__e_machine_nocache(struct perf_env *env, uint32_t *e_flags)
{
        uint16_t e_machine = EM_NONE;
        const char *arch = NULL;
        int is_64_bit = -1;

        if (e_flags)
                *e_flags = 0;

        if (env) {
                arch = env->arch;
                is_64_bit = env->kernel_is_64_bit;
        }

        if (!arch) {
                static struct utsname uts = { .machine[0] = '\0', };

                if (uts.machine[0] == '\0')
                        uname(&uts);
                if (uts.machine[0] != '\0')
                        arch = uts.machine;
        }

        e_machine = perf_arch_to_e_machine(arch, is_64_bit);

        if (e_flags)
                *e_flags = (e_machine == EM_HOST) ? EF_HOST : 0;

        return e_machine;
}

uint16_t perf_env__e_machine(struct perf_env *env, uint32_t *e_flags)
{
        uint16_t e_machine;
        uint32_t local_e_flags = 0;

        if (env && env->e_machine != EM_NONE) {
                if (e_flags)
                        *e_flags = env->e_flags;

                return env->e_machine;
        }
        e_machine = perf_env__e_machine_nocache(env, &local_e_flags);
        /*
         * Only cache the e_machine in perf_env if env->arch is not NULL.
         * If env->arch is NULL, the e_machine is just a fallback to EM_HOST.
         * Caching it permanently would prevent dynamic, more accurate
         * thread-based session e_machine scanning later in
         * perf_session__e_machine().
         */
        if (env && env->arch) {
                env->e_machine = e_machine;
                env->e_flags = local_e_flags;
        }
        if (e_flags)
                *e_flags = local_e_flags;

        return e_machine;
}

const char *perf_env__arch(struct perf_env *env)
{
        uint16_t e_machine;
        const char *arch;

        if (!env) {
                static struct utsname uts = { .machine[0] = '\0', };
                uint16_t host_e_machine;

                if (uts.machine[0] == '\0')
                        uname(&uts);
                if (uts.machine[0] != '\0') {
                        host_e_machine = perf_arch_to_e_machine(uts.machine, -1);
                        return e_machine_to_perf_arch(host_e_machine);
                }
                return e_machine_to_perf_arch(EM_HOST);
        }

        /*
         * Lazily compute/allocate arch. The e_machine may have been
         * read from a data file and so may not be EM_HOST.
         */
        e_machine = perf_env__e_machine(env, /*e_flags=*/NULL);
        arch = e_machine_to_perf_arch(e_machine);

        if (e_machine == EM_RISCV && perf_env__kernel_is_64_bit(env) == 1)
                arch = "riscv64";
        else if (e_machine == EM_MIPS && perf_env__kernel_is_64_bit(env) == 1)
                arch = "mips64";
        else if (e_machine == EM_PARISC && perf_env__kernel_is_64_bit(env) == 1)
                arch = "parisc64";

        return arch;
}

const char *arch_syscalls__strerrno(uint16_t e_machine, int err);

const char *perf_env__arch_strerrno(uint16_t e_machine, int err)
{
        return arch_syscalls__strerrno(e_machine, err);
}

const char *perf_env__cpuid(struct perf_env *env)
{
        int status;

        if (!env->cpuid) { /* Assume local operation */
                status = perf_env__read_cpuid(env);
                if (status)
                        return NULL;
        }

        return env->cpuid;
}

int perf_env__nr_pmu_mappings(struct perf_env *env)
{
        int status;

        if (!env->nr_pmu_mappings) { /* Assume local operation */
                status = perf_env__read_pmu_mappings(env);
                if (status)
                        return 0;
        }

        return env->nr_pmu_mappings;
}

const char *perf_env__pmu_mappings(struct perf_env *env)
{
        int status;

        if (!env->pmu_mappings) { /* Assume local operation */
                status = perf_env__read_pmu_mappings(env);
                if (status)
                        return NULL;
        }

        return env->pmu_mappings;
}

int perf_env__numa_node(struct perf_env *env, struct perf_cpu cpu)
{
        if (!env->nr_numa_map) {
                struct numa_node *nn;
                int i, nr = 0;

                for (i = 0; i < env->nr_numa_nodes; i++) {
                        nn = &env->numa_nodes[i];
                        nr = max(nr, (int)perf_cpu_map__max(nn->map).cpu);
                }

                nr++;

                /*
                 * We initialize the numa_map array to prepare
                 * it for missing cpus, which return node -1
                 */
                env->numa_map = malloc(nr * sizeof(int));
                if (!env->numa_map)
                        return -1;

                for (i = 0; i < nr; i++)
                        env->numa_map[i] = -1;

                env->nr_numa_map = nr;

                for (i = 0; i < env->nr_numa_nodes; i++) {
                        struct perf_cpu tmp;
                        unsigned int j;

                        nn = &env->numa_nodes[i];
                        perf_cpu_map__for_each_cpu(tmp, j, nn->map)
                                env->numa_map[tmp.cpu] = i;
                }
        }

        return cpu.cpu >= 0 && cpu.cpu < env->nr_numa_map ? env->numa_map[cpu.cpu] : -1;
}

bool perf_env__has_pmu_mapping(struct perf_env *env, const char *pmu_name)
{
        char *pmu_mapping = env->pmu_mappings, *colon;

        for (int i = 0; i < env->nr_pmu_mappings; ++i) {
                if (strtoul(pmu_mapping, &colon, 0) == ULONG_MAX || *colon != ':')
                        goto out_error;

                pmu_mapping = colon + 1;
                if (strcmp(pmu_mapping, pmu_name) == 0)
                        return true;

                pmu_mapping += strlen(pmu_mapping) + 1;
        }
out_error:
        return false;
}

char *perf_env__find_pmu_cap(struct perf_env *env, const char *pmu_name,
                             const char *cap)
{
        char *cap_eq;
        int cap_size;
        char **ptr;
        int i, j;

        if (!pmu_name || !cap)
                return NULL;

        cap_size = strlen(cap);
        cap_eq = zalloc(cap_size + 2);
        if (!cap_eq)
                return NULL;

        memcpy(cap_eq, cap, cap_size);
        cap_eq[cap_size] = '=';

        if (!strcmp(pmu_name, "cpu")) {
                for (i = 0; i < env->nr_cpu_pmu_caps; i++) {
                        if (!strncmp(env->cpu_pmu_caps[i], cap_eq, cap_size + 1)) {
                                free(cap_eq);
                                return &env->cpu_pmu_caps[i][cap_size + 1];
                        }
                }
                goto out;
        }

        for (i = 0; i < env->nr_pmus_with_caps; i++) {
                if (strcmp(env->pmu_caps[i].pmu_name, pmu_name))
                        continue;

                ptr = env->pmu_caps[i].caps;

                for (j = 0; j < env->pmu_caps[i].nr_caps; j++) {
                        if (!strncmp(ptr[j], cap_eq, cap_size + 1)) {
                                free(cap_eq);
                                return &ptr[j][cap_size + 1];
                        }
                }
        }

out:
        free(cap_eq);
        return NULL;
}

void perf_env__find_br_cntr_info(struct perf_env *env,
                                 unsigned int *nr,
                                 unsigned int *width)
{
        if (nr) {
                *nr = env->cpu_pmu_caps ? env->br_cntr_nr :
                                          env->pmu_caps->br_cntr_nr;
        }

        if (width) {
                *width = env->cpu_pmu_caps ? env->br_cntr_width :
                                             env->pmu_caps->br_cntr_width;
        }
}

bool perf_env__is_x86_amd_cpu(struct perf_env *env)
{
        static int is_amd; /* 0: Uninitialized, 1: Yes, -1: No */

        if (is_amd == 0)
                is_amd = env->cpuid && strstarts(env->cpuid, "AuthenticAMD") ? 1 : -1;

        return is_amd >= 1 ? true : false;
}

bool x86__is_amd_cpu(void)
{
        struct perf_env env = { .total_mem = 0, };
        bool is_amd;

        perf_env__init(&env);
        perf_env__cpuid(&env);
        is_amd = perf_env__is_x86_amd_cpu(&env);
        perf_env__exit(&env);

        return is_amd;
}

bool perf_env__is_x86_intel_cpu(struct perf_env *env)
{
        static int is_intel; /* 0: Uninitialized, 1: Yes, -1: No */

        if (is_intel == 0)
                is_intel = env->cpuid && strstarts(env->cpuid, "GenuineIntel") ? 1 : -1;

        return is_intel >= 1 ? true : false;
}

bool x86__is_intel_cpu(void)
{
        struct perf_env env = { .total_mem = 0, };
        bool is_intel;

        perf_env__init(&env);
        perf_env__cpuid(&env);
        is_intel = perf_env__is_x86_intel_cpu(&env);
        perf_env__exit(&env);

        return is_intel;
}