// SPDX-License-Identifier: GPL-2.0
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <api/fs/fs.h>
#include <linux/kernel.h>
#include "mem-events.h"
#include "debug.h"
#include "symbol.h"
#include "sort.h"

unsigned int perf_mem_events__loads_ldlat = 30;

#define E(t, n, s) { .tag = t, .name = n, .sysfs_name = s }

struct perf_mem_event perf_mem_events[PERF_MEM_EVENTS__MAX] = {
	E("ldlat-loads",	"cpu/mem-loads,ldlat=%u/P",	"mem-loads"),
	E("ldlat-stores",	"cpu/mem-stores/P",		"mem-stores"),
};
#undef E

#undef E

static char mem_loads_name[100];
static bool mem_loads_name__init;

char * __weak perf_mem_events__name(int i)
{
	if (i == PERF_MEM_EVENTS__LOAD) {
		if (!mem_loads_name__init) {
			mem_loads_name__init = true;
			scnprintf(mem_loads_name, sizeof(mem_loads_name),
				  perf_mem_events[i].name,
				  perf_mem_events__loads_ldlat);
		}
		return mem_loads_name;
	}

	return (char *)perf_mem_events[i].name;
}

int perf_mem_events__parse(const char *str)
{
	char *tok, *saveptr = NULL;
	bool found = false;
	char *buf;
	int j;

	/* We need buffer that we know we can write to. */
	buf = malloc(strlen(str) + 1);
	if (!buf)
		return -ENOMEM;

	strcpy(buf, str);

	tok = strtok_r((char *)buf, ",", &saveptr);

	while (tok) {
		for (j = 0; j < PERF_MEM_EVENTS__MAX; j++) {
			struct perf_mem_event *e = &perf_mem_events[j];

			if (strstr(e->tag, tok))
				e->record = found = true;
		}

		tok = strtok_r(NULL, ",", &saveptr);
	}

	free(buf);

	if (found)
		return 0;

	pr_err("failed: event '%s' not found, use '-e list' to get list of available events\n", str);
	return -1;
}

int perf_mem_events__init(void)
{
	const char *mnt = sysfs__mount();
	bool found = false;
	int j;

	if (!mnt)
		return -ENOENT;

	for (j = 0; j < PERF_MEM_EVENTS__MAX; j++) {
		char path[PATH_MAX];
		struct perf_mem_event *e = &perf_mem_events[j];
		struct stat st;

		scnprintf(path, PATH_MAX, "%s/devices/cpu/events/%s",
			  mnt, e->sysfs_name);

		if (!stat(path, &st))
			e->supported = found = true;
	}

	return found ? 0 : -ENOENT;
}

static const char * const tlb_access[] = {
	"N/A",
	"HIT",
	"MISS",
	"L1",
	"L2",
	"Walker",
	"Fault",
};

int perf_mem__tlb_scnprintf(char *out, size_t sz, struct mem_info *mem_info)
{
	size_t l = 0, i;
	u64 m = PERF_MEM_TLB_NA;
	u64 hit, miss;

	sz -= 1; /* -1 for null termination */
	out[0] = '\0';

	if (mem_info)
		m = mem_info->data_src.mem_dtlb;

	hit = m & PERF_MEM_TLB_HIT;
	miss = m & PERF_MEM_TLB_MISS;

	/* already taken care of */
	m &= ~(PERF_MEM_TLB_HIT|PERF_MEM_TLB_MISS);

	for (i = 0; m && i < ARRAY_SIZE(tlb_access); i++, m >>= 1) {
		if (!(m & 0x1))
			continue;
		if (l) {
			strcat(out, " or ");
			l += 4;
		}
		l += scnprintf(out + l, sz - l, tlb_access[i]);
	}
	if (*out == '\0')
		l += scnprintf(out, sz - l, "N/A");
	if (hit)
		l += scnprintf(out + l, sz - l, " hit");
	if (miss)
		l += scnprintf(out + l, sz - l, " miss");

	return l;
}

static const char * const mem_lvl[] = {
	"N/A",
	"HIT",
	"MISS",
	"L1",
	"LFB",
	"L2",
	"L3",
	"Local RAM",
	"Remote RAM (1 hop)",
	"Remote RAM (2 hops)",
	"Remote Cache (1 hop)",
	"Remote Cache (2 hops)",
	"I/O",
	"Uncached",
};

static const char * const mem_lvlnum[] = {
	[PERF_MEM_LVLNUM_ANY_CACHE] = "Any cache",
	[PERF_MEM_LVLNUM_LFB] = "LFB",
	[PERF_MEM_LVLNUM_RAM] = "RAM",
	[PERF_MEM_LVLNUM_PMEM] = "PMEM",
	[PERF_MEM_LVLNUM_NA] = "N/A",
};

int perf_mem__lvl_scnprintf(char *out, size_t sz, struct mem_info *mem_info)
{
	size_t i, l = 0;
	u64 m =  PERF_MEM_LVL_NA;
	u64 hit, miss;
	int printed;

	if (mem_info)
		m  = mem_info->data_src.mem_lvl;

	sz -= 1; /* -1 for null termination */
	out[0] = '\0';

	hit = m & PERF_MEM_LVL_HIT;
	miss = m & PERF_MEM_LVL_MISS;

	/* already taken care of */
	m &= ~(PERF_MEM_LVL_HIT|PERF_MEM_LVL_MISS);


	if (mem_info && mem_info->data_src.mem_remote) {
		strcat(out, "Remote ");
		l += 7;
	}

	printed = 0;
	for (i = 0; m && i < ARRAY_SIZE(mem_lvl); i++, m >>= 1) {
		if (!(m & 0x1))
			continue;
		if (printed++) {
			strcat(out, " or ");
			l += 4;
		}
		l += scnprintf(out + l, sz - l, mem_lvl[i]);
	}

	if (mem_info && mem_info->data_src.mem_lvl_num) {
		int lvl = mem_info->data_src.mem_lvl_num;
		if (printed++) {
			strcat(out, " or ");
			l += 4;
		}
		if (mem_lvlnum[lvl])
			l += scnprintf(out + l, sz - l, mem_lvlnum[lvl]);
		else
			l += scnprintf(out + l, sz - l, "L%d", lvl);
	}

	if (l == 0)
		l += scnprintf(out + l, sz - l, "N/A");
	if (hit)
		l += scnprintf(out + l, sz - l, " hit");
	if (miss)
		l += scnprintf(out + l, sz - l, " miss");

	return l;
}

static const char * const snoop_access[] = {
	"N/A",
	"None",
	"Hit",
	"Miss",
	"HitM",
};

int perf_mem__snp_scnprintf(char *out, size_t sz, struct mem_info *mem_info)
{
	size_t i, l = 0;
	u64 m = PERF_MEM_SNOOP_NA;

	sz -= 1; /* -1 for null termination */
	out[0] = '\0';

	if (mem_info)
		m = mem_info->data_src.mem_snoop;

	for (i = 0; m && i < ARRAY_SIZE(snoop_access); i++, m >>= 1) {
		if (!(m & 0x1))
			continue;
		if (l) {
			strcat(out, " or ");
			l += 4;
		}
		l += scnprintf(out + l, sz - l, snoop_access[i]);
	}
	if (mem_info &&
	     (mem_info->data_src.mem_snoopx & PERF_MEM_SNOOPX_FWD)) {
		if (l) {
			strcat(out, " or ");
			l += 4;
		}
		l += scnprintf(out + l, sz - l, "Fwd");
	}

	if (*out == '\0')
		l += scnprintf(out, sz - l, "N/A");

	return l;
}

int perf_mem__lck_scnprintf(char *out, size_t sz, struct mem_info *mem_info)
{
	u64 mask = PERF_MEM_LOCK_NA;
	int l;

	if (mem_info)
		mask = mem_info->data_src.mem_lock;

	if (mask & PERF_MEM_LOCK_NA)
		l = scnprintf(out, sz, "N/A");
	else if (mask & PERF_MEM_LOCK_LOCKED)
		l = scnprintf(out, sz, "Yes");
	else
		l = scnprintf(out, sz, "No");

	return l;
}

int perf_script__meminfo_scnprintf(char *out, size_t sz, struct mem_info *mem_info)
{
	int i = 0;

	i += perf_mem__lvl_scnprintf(out, sz, mem_info);
	i += scnprintf(out + i, sz - i, "|SNP ");
	i += perf_mem__snp_scnprintf(out + i, sz - i, mem_info);
	i += scnprintf(out + i, sz - i, "|TLB ");
	i += perf_mem__tlb_scnprintf(out + i, sz - i, mem_info);
	i += scnprintf(out + i, sz - i, "|LCK ");
	i += perf_mem__lck_scnprintf(out + i, sz - i, mem_info);

	return i;
}

int c2c_decode_stats(struct c2c_stats *stats, struct mem_info *mi)
{
	union perf_mem_data_src *data_src = &mi->data_src;
	u64 daddr  = mi->daddr.addr;
	u64 op     = data_src->mem_op;
	u64 lvl    = data_src->mem_lvl;
	u64 snoop  = data_src->mem_snoop;
	u64 lock   = data_src->mem_lock;
	/*
	 * Skylake might report unknown remote level via this
	 * bit, consider it when evaluating remote HITMs.
	 */
	bool mrem  = data_src->mem_remote;
	int err = 0;

#define HITM_INC(__f)		\
do {				\
	stats->__f++;		\
	stats->tot_hitm++;	\
} while (0)

#define P(a, b) PERF_MEM_##a##_##b

	stats->nr_entries++;

	if (lock & P(LOCK, LOCKED)) stats->locks++;

	if (op & P(OP, LOAD)) {
		/* load */
		stats->load++;

		if (!daddr) {
			stats->ld_noadrs++;
			return -1;
		}

		if (lvl & P(LVL, HIT)) {
			if (lvl & P(LVL, UNC)) stats->ld_uncache++;
			if (lvl & P(LVL, IO))  stats->ld_io++;
			if (lvl & P(LVL, LFB)) stats->ld_fbhit++;
			if (lvl & P(LVL, L1 )) stats->ld_l1hit++;
			if (lvl & P(LVL, L2 )) stats->ld_l2hit++;
			if (lvl & P(LVL, L3 )) {
				if (snoop & P(SNOOP, HITM))
					HITM_INC(lcl_hitm);
				else
					stats->ld_llchit++;
			}

			if (lvl & P(LVL, LOC_RAM)) {
				stats->lcl_dram++;
				if (snoop & P(SNOOP, HIT))
					stats->ld_shared++;
				else
					stats->ld_excl++;
			}

			if ((lvl & P(LVL, REM_RAM1)) ||
			    (lvl & P(LVL, REM_RAM2)) ||
			     mrem) {
				stats->rmt_dram++;
				if (snoop & P(SNOOP, HIT))
					stats->ld_shared++;
				else
					stats->ld_excl++;
			}
		}

		if ((lvl & P(LVL, REM_CCE1)) ||
		    (lvl & P(LVL, REM_CCE2)) ||
		     mrem) {
			if (snoop & P(SNOOP, HIT))
				stats->rmt_hit++;
			else if (snoop & P(SNOOP, HITM))
				HITM_INC(rmt_hitm);
		}

		if ((lvl & P(LVL, MISS)))
			stats->ld_miss++;

	} else if (op & P(OP, STORE)) {
		/* store */
		stats->store++;

		if (!daddr) {
			stats->st_noadrs++;
			return -1;
		}

		if (lvl & P(LVL, HIT)) {
			if (lvl & P(LVL, UNC)) stats->st_uncache++;
			if (lvl & P(LVL, L1 )) stats->st_l1hit++;
		}
		if (lvl & P(LVL, MISS))
			if (lvl & P(LVL, L1)) stats->st_l1miss++;
	} else {
		/* unparsable data_src? */
		stats->noparse++;
		return -1;
	}

	if (!mi->daddr.map || !mi->iaddr.map) {
		stats->nomap++;
		return -1;
	}

#undef P
#undef HITM_INC
	return err;
}

void c2c_add_stats(struct c2c_stats *stats, struct c2c_stats *add)
{
	stats->nr_entries	+= add->nr_entries;

	stats->locks		+= add->locks;
	stats->store		+= add->store;
	stats->st_uncache	+= add->st_uncache;
	stats->st_noadrs	+= add->st_noadrs;
	stats->st_l1hit		+= add->st_l1hit;
	stats->st_l1miss	+= add->st_l1miss;
	stats->load		+= add->load;
	stats->ld_excl		+= add->ld_excl;
	stats->ld_shared	+= add->ld_shared;
	stats->ld_uncache	+= add->ld_uncache;
	stats->ld_io		+= add->ld_io;
	stats->ld_miss		+= add->ld_miss;
	stats->ld_noadrs	+= add->ld_noadrs;
	stats->ld_fbhit		+= add->ld_fbhit;
	stats->ld_l1hit		+= add->ld_l1hit;
	stats->ld_l2hit		+= add->ld_l2hit;
	stats->ld_llchit	+= add->ld_llchit;
	stats->lcl_hitm		+= add->lcl_hitm;
	stats->rmt_hitm		+= add->rmt_hitm;
	stats->tot_hitm		+= add->tot_hitm;
	stats->rmt_hit		+= add->rmt_hit;
	stats->lcl_dram		+= add->lcl_dram;
	stats->rmt_dram		+= add->rmt_dram;
	stats->nomap		+= add->nomap;
	stats->noparse		+= add->noparse;
}