// SPDX-License-Identifier: GPL-2.0
#include <api/fs/fs.h>
#include "cpumap.h"
#include "debug.h"
#include "event.h"
#include <assert.h>
#include <dirent.h>
#include <stdio.h>
#include <stdlib.h>
#include <linux/bitmap.h>
#include "asm/bug.h"

#include <linux/ctype.h>
#include <linux/zalloc.h>
#include <internal/cpumap.h>

static struct perf_cpu max_cpu_num;
static struct perf_cpu max_present_cpu_num;
static int max_node_num;
/**
 * The numa node X as read from /sys/devices/system/node/nodeX indexed by the
 * CPU number.
 */
static int *cpunode_map;

bool perf_record_cpu_map_data__test_bit(int i,
                                        const struct perf_record_cpu_map_data *data)
{
        int bit_word32 = i / 32;
        __u32 bit_mask32 = 1U << (i & 31);
        int bit_word64 = i / 64;
        __u64 bit_mask64 = ((__u64)1) << (i & 63);

        return (data->mask32_data.long_size == 4)
                ? (bit_word32 < data->mask32_data.nr) &&
                (data->mask32_data.mask[bit_word32] & bit_mask32) != 0
                : (bit_word64 < data->mask64_data.nr) &&
                (data->mask64_data.mask[bit_word64] & bit_mask64) != 0;
}

/* Read ith mask value from data into the given 64-bit sized bitmap */
static void perf_record_cpu_map_data__read_one_mask(const struct perf_record_cpu_map_data *data,
                                                    int i, unsigned long *bitmap)
{
#if __SIZEOF_LONG__ == 8
        if (data->mask32_data.long_size == 4)
                bitmap[0] = data->mask32_data.mask[i];
        else
                bitmap[0] = data->mask64_data.mask[i];
#else
        if (data->mask32_data.long_size == 4) {
                bitmap[0] = data->mask32_data.mask[i];
                bitmap[1] = 0;
        } else {
#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
                bitmap[0] = (unsigned long)(data->mask64_data.mask[i] >> 32);
                bitmap[1] = (unsigned long)data->mask64_data.mask[i];
#else
                bitmap[0] = (unsigned long)data->mask64_data.mask[i];
                bitmap[1] = (unsigned long)(data->mask64_data.mask[i] >> 32);
#endif
        }
#endif
}
static struct perf_cpu_map *cpu_map__from_entries(const struct perf_record_cpu_map_data *data)
{
        struct perf_cpu_map *map;

        map = perf_cpu_map__empty_new(data->cpus_data.nr);
        if (!map)
                return NULL;

        for (unsigned int i = 0; i < data->cpus_data.nr; i++) {
                /*
                 * Special treatment for -1, which is not real cpu number,
                 * and we need to use (int) -1 to initialize map[i],
                 * otherwise it would become 65535.
                 */
                if (data->cpus_data.cpu[i] == (u16) -1) {
                        RC_CHK_ACCESS(map)->map[i].cpu = -1;
                } else if (data->cpus_data.cpu[i] < INT16_MAX) {
                        RC_CHK_ACCESS(map)->map[i].cpu = (int16_t) data->cpus_data.cpu[i];
                } else {
                        pr_err("Invalid cpumap entry %u\n", data->cpus_data.cpu[i]);
                        perf_cpu_map__put(map);
                        return NULL;
                }
        }

        return map;
}

static struct perf_cpu_map *cpu_map__from_mask(const struct perf_record_cpu_map_data *data)
{
        DECLARE_BITMAP(local_copy, 64);
        int weight = 0, mask_nr = data->mask32_data.nr;
        struct perf_cpu_map *map;

        for (int i = 0; i < mask_nr; i++) {
                perf_record_cpu_map_data__read_one_mask(data, i, local_copy);
                weight += bitmap_weight(local_copy, 64);
        }

        map = perf_cpu_map__empty_new(weight);
        if (!map)
                return NULL;

        for (int i = 0, j = 0; i < mask_nr; i++) {
                int cpus_per_i = (i * data->mask32_data.long_size  * BITS_PER_BYTE);
                int cpu;

                perf_record_cpu_map_data__read_one_mask(data, i, local_copy);
                for_each_set_bit(cpu, local_copy, 64) {
                        if (cpu + cpus_per_i < INT16_MAX) {
                                RC_CHK_ACCESS(map)->map[j++].cpu = cpu + cpus_per_i;
                        } else {
                                pr_err("Invalid cpumap entry %d\n", cpu + cpus_per_i);
                                perf_cpu_map__put(map);
                                return NULL;
                        }
                }
        }
        return map;

}

static struct perf_cpu_map *cpu_map__from_range(const struct perf_record_cpu_map_data *data)
{
        struct perf_cpu_map *map;
        unsigned int i = 0;

        map = perf_cpu_map__empty_new(data->range_cpu_data.end_cpu -
                                data->range_cpu_data.start_cpu + 1 + data->range_cpu_data.any_cpu);
        if (!map)
                return NULL;

        if (data->range_cpu_data.any_cpu)
                RC_CHK_ACCESS(map)->map[i++].cpu = -1;

        for (int cpu = data->range_cpu_data.start_cpu; cpu <= data->range_cpu_data.end_cpu;
             i++, cpu++) {
                if (cpu < INT16_MAX) {
                        RC_CHK_ACCESS(map)->map[i].cpu = cpu;
                } else {
                        pr_err("Invalid cpumap entry %d\n", cpu);
                        perf_cpu_map__put(map);
                        return NULL;
                }
        }

        return map;
}

struct perf_cpu_map *cpu_map__new_data(const struct perf_record_cpu_map_data *data)
{
        switch (data->type) {
        case PERF_CPU_MAP__CPUS:
                return cpu_map__from_entries(data);
        case PERF_CPU_MAP__MASK:
                return cpu_map__from_mask(data);
        case PERF_CPU_MAP__RANGE_CPUS:
                return cpu_map__from_range(data);
        default:
                pr_err("cpu_map__new_data unknown type %d\n", data->type);
                return NULL;
        }
}

size_t cpu_map__fprintf(struct perf_cpu_map *map, FILE *fp)
{
#define BUFSIZE 1024
        char buf[BUFSIZE];

        cpu_map__snprint(map, buf, sizeof(buf));
        return fprintf(fp, "%s\n", buf);
#undef BUFSIZE
}

struct perf_cpu_map *perf_cpu_map__empty_new(int nr)
{
        struct perf_cpu_map *cpus = perf_cpu_map__alloc(nr);

        if (cpus != NULL) {
                for (int i = 0; i < nr; i++)
                        RC_CHK_ACCESS(cpus)->map[i].cpu = -1;
        }

        return cpus;
}

struct cpu_aggr_map *cpu_aggr_map__empty_new(int nr)
{
        struct cpu_aggr_map *cpus = malloc(sizeof(*cpus) + sizeof(struct aggr_cpu_id) * nr);

        if (cpus != NULL) {
                int i;

                cpus->nr = nr;
                for (i = 0; i < nr; i++)
                        cpus->map[i] = aggr_cpu_id__empty();
        }

        return cpus;
}

static int cpu__get_topology_int(int cpu, const char *name, int *value)
{
        char path[PATH_MAX];

        snprintf(path, PATH_MAX,
                "devices/system/cpu/cpu%d/topology/%s", cpu, name);

        return sysfs__read_int(path, value);
}

int cpu__get_socket_id(struct perf_cpu cpu)
{
        int value, ret = cpu__get_topology_int(cpu.cpu, "physical_package_id", &value);
        return ret ?: value;
}

struct aggr_cpu_id aggr_cpu_id__socket(struct perf_cpu cpu, void *data __maybe_unused)
{
        struct aggr_cpu_id id = aggr_cpu_id__empty();

        id.socket = cpu__get_socket_id(cpu);
        return id;
}

static int aggr_cpu_id__cmp(const void *a_pointer, const void *b_pointer)
{
        struct aggr_cpu_id *a = (struct aggr_cpu_id *)a_pointer;
        struct aggr_cpu_id *b = (struct aggr_cpu_id *)b_pointer;

        if (a->node != b->node)
                return a->node - b->node;
        else if (a->socket != b->socket)
                return a->socket - b->socket;
        else if (a->die != b->die)
                return a->die - b->die;
        else if (a->cluster != b->cluster)
                return a->cluster - b->cluster;
        else if (a->cache_lvl != b->cache_lvl)
                return a->cache_lvl - b->cache_lvl;
        else if (a->cache != b->cache)
                return a->cache - b->cache;
        else if (a->core != b->core)
                return a->core - b->core;
        else
                return a->thread_idx - b->thread_idx;
}

struct cpu_aggr_map *cpu_aggr_map__new(const struct perf_cpu_map *cpus,
                                       aggr_cpu_id_get_t get_id,
                                       void *data, bool needs_sort)
{
        int idx;
        struct perf_cpu cpu;
        struct cpu_aggr_map *c = cpu_aggr_map__empty_new(perf_cpu_map__nr(cpus));

        if (!c)
                return NULL;

        /* Reset size as it may only be partially filled */
        c->nr = 0;

        perf_cpu_map__for_each_cpu(cpu, idx, cpus) {
                bool duplicate = false;
                struct aggr_cpu_id cpu_id = get_id(cpu, data);

                for (int j = 0; j < c->nr; j++) {
                        if (aggr_cpu_id__equal(&cpu_id, &c->map[j])) {
                                duplicate = true;
                                break;
                        }
                }
                if (!duplicate) {
                        c->map[c->nr] = cpu_id;
                        c->nr++;
                }
        }
        /* Trim. */
        if (c->nr != perf_cpu_map__nr(cpus)) {
                struct cpu_aggr_map *trimmed_c =
                        realloc(c,
                                sizeof(struct cpu_aggr_map) + sizeof(struct aggr_cpu_id) * c->nr);

                if (trimmed_c)
                        c = trimmed_c;
        }

        /* ensure we process id in increasing order */
        if (needs_sort)
                qsort(c->map, c->nr, sizeof(struct aggr_cpu_id), aggr_cpu_id__cmp);

        return c;

}

int cpu__get_die_id(struct perf_cpu cpu)
{
        int value, ret = cpu__get_topology_int(cpu.cpu, "die_id", &value);

        return ret ?: value;
}

struct aggr_cpu_id aggr_cpu_id__die(struct perf_cpu cpu, void *data)
{
        struct aggr_cpu_id id;
        int die;

        die = cpu__get_die_id(cpu);
        /* There is no die_id on legacy system. */
        if (die < 0)
                die = 0;

        /*
         * die_id is relative to socket, so start
         * with the socket ID and then add die to
         * make a unique ID.
         */
        id = aggr_cpu_id__socket(cpu, data);
        if (aggr_cpu_id__is_empty(&id))
                return id;

        id.die = die;
        return id;
}

int cpu__get_cluster_id(struct perf_cpu cpu)
{
        int value, ret = cpu__get_topology_int(cpu.cpu, "cluster_id", &value);

        return ret ?: value;
}

struct aggr_cpu_id aggr_cpu_id__cluster(struct perf_cpu cpu, void *data)
{
        int cluster = cpu__get_cluster_id(cpu);
        struct aggr_cpu_id id;

        /* There is no cluster_id on legacy system. */
        if (cluster < 0)
                cluster = 0;

        id = aggr_cpu_id__die(cpu, data);
        if (aggr_cpu_id__is_empty(&id))
                return id;

        id.cluster = cluster;
        return id;
}

int cpu__get_core_id(struct perf_cpu cpu)
{
        int value, ret = cpu__get_topology_int(cpu.cpu, "core_id", &value);
        return ret ?: value;
}

struct aggr_cpu_id aggr_cpu_id__core(struct perf_cpu cpu, void *data)
{
        struct aggr_cpu_id id;
        int core = cpu__get_core_id(cpu);

        /* aggr_cpu_id__die returns a struct with socket die, and cluster set. */
        id = aggr_cpu_id__cluster(cpu, data);
        if (aggr_cpu_id__is_empty(&id))
                return id;

        /*
         * core_id is relative to socket and die, we need a global id.
         * So we combine the result from cpu_map__get_die with the core id
         */
        id.core = core;
        return id;

}

struct aggr_cpu_id aggr_cpu_id__cpu(struct perf_cpu cpu, void *data)
{
        struct aggr_cpu_id id;

        /* aggr_cpu_id__core returns a struct with socket, die and core set. */
        id = aggr_cpu_id__core(cpu, data);
        if (aggr_cpu_id__is_empty(&id))
                return id;

        id.cpu = cpu;
        return id;

}

struct aggr_cpu_id aggr_cpu_id__node(struct perf_cpu cpu, void *data __maybe_unused)
{
        struct aggr_cpu_id id = aggr_cpu_id__empty();

        id.node = cpu__get_node(cpu);
        return id;
}

struct aggr_cpu_id aggr_cpu_id__global(struct perf_cpu cpu, void *data __maybe_unused)
{
        struct aggr_cpu_id id = aggr_cpu_id__empty();

        /* it always aggregates to the cpu 0 */
        cpu.cpu = 0;
        id.cpu = cpu;
        return id;
}

/* setup simple routines to easily access node numbers given a cpu number */
static int get_max_num(char *path, int *max)
{
        size_t num;
        char *buf;
        int err = 0;

        if (filename__read_str(path, &buf, &num))
                return -1;

        buf[num] = '\0';

        /* start on the right, to find highest node num */
        while (--num) {
                if ((buf[num] == ',') || (buf[num] == '-')) {
                        num++;
                        break;
                }
        }
        if (sscanf(&buf[num], "%d", max) < 1) {
                err = -1;
                goto out;
        }

        /* convert from 0-based to 1-based */
        (*max)++;

out:
        free(buf);
        return err;
}

/* Determine highest possible cpu in the system for sparse allocation */
static void set_max_cpu_num(void)
{
        const char *mnt;
        char path[PATH_MAX];
        int max, ret = -1;

        /* set up default */
        max_cpu_num.cpu = 4096;
        max_present_cpu_num.cpu = 4096;

        mnt = sysfs__mountpoint();
        if (!mnt)
                goto out;

        /* get the highest possible cpu number for a sparse allocation */
        ret = snprintf(path, PATH_MAX, "%s/devices/system/cpu/possible", mnt);
        if (ret >= PATH_MAX) {
                pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
                goto out;
        }

        ret = get_max_num(path, &max);
        if (ret)
                goto out;

        max_cpu_num.cpu = max;

        /* get the highest present cpu number for a sparse allocation */
        ret = snprintf(path, PATH_MAX, "%s/devices/system/cpu/present", mnt);
        if (ret >= PATH_MAX) {
                pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
                goto out;
        }

        ret = get_max_num(path, &max);

        if (!ret && max > INT16_MAX) {
                pr_err("Read out of bounds max cpus of %d\n", max);
                ret = -1;
        }
        if (!ret)
                max_present_cpu_num.cpu = (int16_t)max;
out:
        if (ret)
                pr_err("Failed to read max cpus, using default of %d\n", max_cpu_num.cpu);
}

/* Determine highest possible node in the system for sparse allocation */
static void set_max_node_num(void)
{
        const char *mnt;
        char path[PATH_MAX];
        int ret = -1;

        /* set up default */
        max_node_num = 8;

        mnt = sysfs__mountpoint();
        if (!mnt)
                goto out;

        /* get the highest possible cpu number for a sparse allocation */
        ret = snprintf(path, PATH_MAX, "%s/devices/system/node/possible", mnt);
        if (ret >= PATH_MAX) {
                pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
                goto out;
        }

        ret = get_max_num(path, &max_node_num);

out:
        if (ret)
                pr_err("Failed to read max nodes, using default of %d\n", max_node_num);
}

int cpu__max_node(void)
{
        if (unlikely(!max_node_num))
                set_max_node_num();

        return max_node_num;
}

struct perf_cpu cpu__max_cpu(void)
{
        if (unlikely(!max_cpu_num.cpu))
                set_max_cpu_num();

        return max_cpu_num;
}

struct perf_cpu cpu__max_present_cpu(void)
{
        if (unlikely(!max_present_cpu_num.cpu))
                set_max_cpu_num();

        return max_present_cpu_num;
}


int cpu__get_node(struct perf_cpu cpu)
{
        if (unlikely(cpunode_map == NULL)) {
                pr_debug("cpu_map not initialized\n");
                return -1;
        }

        return cpunode_map[cpu.cpu];
}

static int init_cpunode_map(void)
{
        int i;

        set_max_cpu_num();
        set_max_node_num();

        cpunode_map = calloc(max_cpu_num.cpu, sizeof(int));
        if (!cpunode_map) {
                pr_err("%s: calloc failed\n", __func__);
                return -1;
        }

        for (i = 0; i < max_cpu_num.cpu; i++)
                cpunode_map[i] = -1;

        return 0;
}

int cpu__setup_cpunode_map(void)
{
        struct dirent *dent1, *dent2;
        DIR *dir1, *dir2;
        unsigned int cpu, mem;
        char buf[PATH_MAX];
        char path[PATH_MAX];
        const char *mnt;
        int n;

        /* initialize globals */
        if (init_cpunode_map())
                return -1;

        mnt = sysfs__mountpoint();
        if (!mnt)
                return 0;

        n = snprintf(path, PATH_MAX, "%s/devices/system/node", mnt);
        if (n >= PATH_MAX) {
                pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
                return -1;
        }

        dir1 = opendir(path);
        if (!dir1)
                return 0;

        /* walk tree and setup map */
        while ((dent1 = readdir(dir1)) != NULL) {
                if (dent1->d_type != DT_DIR || sscanf(dent1->d_name, "node%u", &mem) < 1)
                        continue;

                n = snprintf(buf, PATH_MAX, "%s/%s", path, dent1->d_name);
                if (n >= PATH_MAX) {
                        pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX);
                        continue;
                }

                dir2 = opendir(buf);
                if (!dir2)
                        continue;
                while ((dent2 = readdir(dir2)) != NULL) {
                        if (dent2->d_type != DT_LNK || sscanf(dent2->d_name, "cpu%u", &cpu) < 1)
                                continue;
                        cpunode_map[cpu] = mem;
                }
                closedir(dir2);
        }
        closedir(dir1);
        return 0;
}

size_t cpu_map__snprint(struct perf_cpu_map *map, char *buf, size_t size)
{
        int i, start = -1;
        bool first = true;
        size_t ret = 0;

#define COMMA first ? "" : ","

        for (i = 0; i < perf_cpu_map__nr(map) + 1; i++) {
                struct perf_cpu cpu = { .cpu = INT16_MAX };
                bool last = i == perf_cpu_map__nr(map);

                if (!last)
                        cpu = perf_cpu_map__cpu(map, i);

                if (start == -1) {
                        start = i;
                        if (last) {
                                ret += snprintf(buf + ret, size - ret,
                                                "%s%d", COMMA,
                                                perf_cpu_map__cpu(map, i).cpu);
                        }
                } else if (((i - start) != (cpu.cpu - perf_cpu_map__cpu(map, start).cpu)) || last) {
                        int end = i - 1;

                        if (start == end) {
                                ret += snprintf(buf + ret, size - ret,
                                                "%s%d", COMMA,
                                                perf_cpu_map__cpu(map, start).cpu);
                        } else {
                                ret += snprintf(buf + ret, size - ret,
                                                "%s%d-%d", COMMA,
                                                perf_cpu_map__cpu(map, start).cpu, perf_cpu_map__cpu(map, end).cpu);
                        }
                        first = false;
                        start = i;
                }
        }

#undef COMMA

        pr_debug2("cpumask list: %s\n", buf);
        return ret;
}

static char hex_char(unsigned char val)
{
        if (val < 10)
                return val + '0';
        if (val < 16)
                return val - 10 + 'a';
        return '?';
}

size_t cpu_map__snprint_mask(struct perf_cpu_map *map, char *buf, size_t size)
{
        int idx;
        char *ptr = buf;
        unsigned char *bitmap;
        struct perf_cpu c, last_cpu = perf_cpu_map__max(map);

        if (buf == NULL || size == 0)
                return 0;

        if (last_cpu.cpu < 0) {
                buf[0] = '\0';
                return 0;
        }

        bitmap = zalloc(last_cpu.cpu / 8 + 1);
        if (bitmap == NULL) {
                buf[0] = '\0';
                return 0;
        }

        perf_cpu_map__for_each_cpu_skip_any(c, idx, map)
                bitmap[c.cpu / 8] |= 1 << (c.cpu % 8);

        for (int cpu = last_cpu.cpu / 4 * 4; cpu >= 0; cpu -= 4) {
                unsigned char bits = bitmap[cpu / 8];

                if (cpu % 8)
                        bits >>= 4;
                else
                        bits &= 0xf;

                *ptr++ = hex_char(bits);
                if ((cpu % 32) == 0 && cpu > 0)
                        *ptr++ = ',';
        }
        *ptr = '\0';
        free(bitmap);

        buf[size - 1] = '\0';
        return ptr - buf;
}

struct perf_cpu_map *cpu_map__online(void) /* thread unsafe */
{
        static struct perf_cpu_map *online;

        if (!online)
                online = perf_cpu_map__new_online_cpus(); /* from /sys/devices/system/cpu/online */

        return perf_cpu_map__get(online);
}

bool aggr_cpu_id__equal(const struct aggr_cpu_id *a, const struct aggr_cpu_id *b)
{
        return a->thread_idx == b->thread_idx &&
                a->node == b->node &&
                a->socket == b->socket &&
                a->die == b->die &&
                a->cluster == b->cluster &&
                a->cache_lvl == b->cache_lvl &&
                a->cache == b->cache &&
                a->core == b->core &&
                a->cpu.cpu == b->cpu.cpu;
}

bool aggr_cpu_id__is_empty(const struct aggr_cpu_id *a)
{
        return a->thread_idx == -1 &&
                a->node == -1 &&
                a->socket == -1 &&
                a->die == -1 &&
                a->cluster == -1 &&
                a->cache_lvl == -1 &&
                a->cache == -1 &&
                a->core == -1 &&
                a->cpu.cpu == -1;
}

struct aggr_cpu_id aggr_cpu_id__empty(void)
{
        struct aggr_cpu_id ret = {
                .thread_idx = -1,
                .node = -1,
                .socket = -1,
                .die = -1,
                .cluster = -1,
                .cache_lvl = -1,
                .cache = -1,
                .core = -1,
                .cpu = (struct perf_cpu){ .cpu = -1 },
        };
        return ret;
}