#include "builtin.h"
  #include "perf.h"
  
  #include "util/util.h"
  #include "util/cache.h"
  #include "util/symbol.h"
  #include "util/thread.h"
  #include "util/header.h"

  #include "util/session.h"

  
  #include "util/parse-options.h"
  #include "util/trace-event.h"
  
  #include "util/debug.h"

  
  #include <linux/rbtree.h>
  
  struct alloc_stat;
  typedef int (*sort_fn_t)(struct alloc_stat *, struct alloc_stat *);
  
  static char const		*input_name = "perf.data";

  static int			alloc_flag;
  static int			caller_flag;

  static int			alloc_lines = -1;
  static int			caller_lines = -1;

  static bool			raw_ip;

  static char			default_sort_order[] = "frag,hit,bytes";

  static int			*cpunode_map;
  static int			max_cpu_num;

  struct alloc_stat {

  	u64	call_site;
  	u64	ptr;

  	u64	bytes_req;
  	u64	bytes_alloc;
  	u32	hit;

  	u32	pingpong;
  
  	short	alloc_cpu;

  
  	struct rb_node node;
  };
  
  static struct rb_root root_alloc_stat;
  static struct rb_root root_alloc_sorted;
  static struct rb_root root_caller_stat;
  static struct rb_root root_caller_sorted;
  
  static unsigned long total_requested, total_allocated;

  static unsigned long nr_allocs, nr_cross_allocs;

  #define PATH_SYS_NODE	"/sys/devices/system/node"
  
  static void init_cpunode_map(void)
  {
  	FILE *fp;
  	int i;
  
  	fp = fopen("/sys/devices/system/cpu/kernel_max", "r");
  	if (!fp) {
  		max_cpu_num = 4096;
  		return;
  	}
  
  	if (fscanf(fp, "%d", &max_cpu_num) < 1)
  		die("Failed to read 'kernel_max' from sysfs");
  	max_cpu_num++;
  
  	cpunode_map = calloc(max_cpu_num, sizeof(int));
  	if (!cpunode_map)
  		die("calloc");
  	for (i = 0; i < max_cpu_num; i++)
  		cpunode_map[i] = -1;
  	fclose(fp);
  }
  
  static void setup_cpunode_map(void)
  {
  	struct dirent *dent1, *dent2;
  	DIR *dir1, *dir2;
  	unsigned int cpu, mem;
  	char buf[PATH_MAX];
  
  	init_cpunode_map();
  
  	dir1 = opendir(PATH_SYS_NODE);
  	if (!dir1)
  		return;

  	while ((dent1 = readdir(dir1)) != NULL) {
  		if (dent1->d_type != DT_DIR ||
  		    sscanf(dent1->d_name, "node%u", &mem) < 1)

  			continue;
  
  		snprintf(buf, PATH_MAX, "%s/%s", PATH_SYS_NODE, dent1->d_name);
  		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;
  		}
  	}
  }

  static void insert_alloc_stat(unsigned long call_site, unsigned long ptr,
  			      int bytes_req, int bytes_alloc, int cpu)

  {
  	struct rb_node **node = &root_alloc_stat.rb_node;
  	struct rb_node *parent = NULL;
  	struct alloc_stat *data = NULL;

  	while (*node) {
  		parent = *node;
  		data = rb_entry(*node, struct alloc_stat, node);
  
  		if (ptr > data->ptr)
  			node = &(*node)->rb_right;
  		else if (ptr < data->ptr)
  			node = &(*node)->rb_left;
  		else
  			break;
  	}
  
  	if (data && data->ptr == ptr) {
  		data->hit++;
  		data->bytes_req += bytes_req;

  		data->bytes_alloc += bytes_alloc;

  	} else {
  		data = malloc(sizeof(*data));

  		if (!data)
  			die("malloc");

  		data->ptr = ptr;

  		data->pingpong = 0;

  		data->hit = 1;
  		data->bytes_req = bytes_req;
  		data->bytes_alloc = bytes_alloc;
  
  		rb_link_node(&data->node, parent, node);
  		rb_insert_color(&data->node, &root_alloc_stat);
  	}

  	data->call_site = call_site;
  	data->alloc_cpu = cpu;

  }
  
  static void insert_caller_stat(unsigned long call_site,
  			      int bytes_req, int bytes_alloc)
  {
  	struct rb_node **node = &root_caller_stat.rb_node;
  	struct rb_node *parent = NULL;
  	struct alloc_stat *data = NULL;

  	while (*node) {
  		parent = *node;
  		data = rb_entry(*node, struct alloc_stat, node);
  
  		if (call_site > data->call_site)
  			node = &(*node)->rb_right;
  		else if (call_site < data->call_site)
  			node = &(*node)->rb_left;
  		else
  			break;
  	}
  
  	if (data && data->call_site == call_site) {
  		data->hit++;
  		data->bytes_req += bytes_req;

  		data->bytes_alloc += bytes_alloc;

  	} else {
  		data = malloc(sizeof(*data));

  		if (!data)
  			die("malloc");

  		data->call_site = call_site;

  		data->pingpong = 0;

  		data->hit = 1;
  		data->bytes_req = bytes_req;
  		data->bytes_alloc = bytes_alloc;
  
  		rb_link_node(&data->node, parent, node);
  		rb_insert_color(&data->node, &root_caller_stat);
  	}
  }

  static void process_alloc_event(void *data,

  				struct event *event,

  				int cpu,

  				u64 timestamp __used,
  				struct thread *thread __used,

  				int node)

  {
  	unsigned long call_site;
  	unsigned long ptr;
  	int bytes_req;
  	int bytes_alloc;

  	int node1, node2;

  	ptr = raw_field_value(event, "ptr", data);
  	call_site = raw_field_value(event, "call_site", data);
  	bytes_req = raw_field_value(event, "bytes_req", data);
  	bytes_alloc = raw_field_value(event, "bytes_alloc", data);

  	insert_alloc_stat(call_site, ptr, bytes_req, bytes_alloc, cpu);

  	insert_caller_stat(call_site, bytes_req, bytes_alloc);
  
  	total_requested += bytes_req;
  	total_allocated += bytes_alloc;

  
  	if (node) {
  		node1 = cpunode_map[cpu];

  		node2 = raw_field_value(event, "node", data);

  		if (node1 != node2)
  			nr_cross_allocs++;
  	}
  	nr_allocs++;

  }

  static int ptr_cmp(struct alloc_stat *, struct alloc_stat *);
  static int callsite_cmp(struct alloc_stat *, struct alloc_stat *);
  
  static struct alloc_stat *search_alloc_stat(unsigned long ptr,
  					    unsigned long call_site,
  					    struct rb_root *root,
  					    sort_fn_t sort_fn)
  {
  	struct rb_node *node = root->rb_node;
  	struct alloc_stat key = { .ptr = ptr, .call_site = call_site };
  
  	while (node) {
  		struct alloc_stat *data;
  		int cmp;
  
  		data = rb_entry(node, struct alloc_stat, node);
  
  		cmp = sort_fn(&key, data);
  		if (cmp < 0)
  			node = node->rb_left;
  		else if (cmp > 0)
  			node = node->rb_right;
  		else
  			return data;
  	}
  	return NULL;
  }

  static void process_free_event(void *data,

  			       struct event *event,
  			       int cpu,

  			       u64 timestamp __used,
  			       struct thread *thread __used)
  {

  	unsigned long ptr;
  	struct alloc_stat *s_alloc, *s_caller;

  	ptr = raw_field_value(event, "ptr", data);

  
  	s_alloc = search_alloc_stat(ptr, 0, &root_alloc_stat, ptr_cmp);
  	if (!s_alloc)
  		return;
  
  	if (cpu != s_alloc->alloc_cpu) {
  		s_alloc->pingpong++;
  
  		s_caller = search_alloc_stat(0, s_alloc->call_site,
  					     &root_caller_stat, callsite_cmp);
  		assert(s_caller);
  		s_caller->pingpong++;
  	}
  	s_alloc->alloc_cpu = -1;

  }

  static void process_raw_event(union perf_event *raw_event __used, void *data,
  			      int cpu, u64 timestamp, struct thread *thread)

  {

  	struct event *event;
  	int type;

  	type = trace_parse_common_type(data);

  	event = trace_find_event(type);
  
  	if (!strcmp(event->name, "kmalloc") ||
  	    !strcmp(event->name, "kmem_cache_alloc")) {

  		process_alloc_event(data, event, cpu, timestamp, thread, 0);

  		return;
  	}
  
  	if (!strcmp(event->name, "kmalloc_node") ||
  	    !strcmp(event->name, "kmem_cache_alloc_node")) {

  		process_alloc_event(data, event, cpu, timestamp, thread, 1);

  		return;
  	}
  
  	if (!strcmp(event->name, "kfree") ||
  	    !strcmp(event->name, "kmem_cache_free")) {

  		process_free_event(data, event, cpu, timestamp, thread);

  		return;
  	}
  }

  static int process_sample_event(union perf_event *event,
  				struct perf_sample *sample,

  				struct perf_evsel *evsel __used,

  				struct perf_session *session)

  {

  	struct thread *thread = perf_session__findnew(session, event->ip.pid);

  	if (thread == NULL) {
  		pr_debug("problem processing %d event, skipping it.
  ",
  			 event->header.type);
  		return -1;
  	}
  
  	dump_printf(" ... thread: %s:%d
  ", thread->comm, thread->pid);

  	process_raw_event(event, sample->raw_data, sample->cpu,
  			  sample->time, thread);

  
  	return 0;
  }

  static struct perf_event_ops event_ops = {

  	.sample			= process_sample_event,

  	.comm			= perf_event__process_comm,

  	.ordered_samples	= true,

  };

  static double fragmentation(unsigned long n_req, unsigned long n_alloc)
  {
  	if (n_alloc == 0)
  		return 0.0;
  	else
  		return 100.0 - (100.0 * n_req / n_alloc);
  }

  static void __print_result(struct rb_root *root, struct perf_session *session,
  			   int n_lines, int is_caller)

  {
  	struct rb_node *next;

  	struct machine *machine;

  	printf("%.102s
  ", graph_dotted_line);
  	printf(" %-34s |",  is_caller ? "Callsite": "Alloc Ptr");

  	printf(" Total_alloc/Per | Total_req/Per   | Hit      | Ping-pong | Frag
  ");

  	printf("%.102s
  ", graph_dotted_line);

  
  	next = rb_first(root);

  	machine = perf_session__find_host_machine(session);
  	if (!machine) {

  		pr_err("__print_result: couldn't find kernel information
  ");
  		return;
  	}

  	while (next && n_lines--) {

  		struct alloc_stat *data = rb_entry(next, struct alloc_stat,
  						   node);
  		struct symbol *sym = NULL;

  		struct map *map;

  		char buf[BUFSIZ];

  		u64 addr;
  
  		if (is_caller) {
  			addr = data->call_site;

  			if (!raw_ip)

  				sym = machine__find_kernel_function(machine, addr, &map, NULL);

  		} else
  			addr = data->ptr;
  
  		if (sym != NULL)

  			snprintf(buf, sizeof(buf), "%s+%" PRIx64 "", sym->name,

  				 addr - map->unmap_ip(map, sym->start));

  		else

  			snprintf(buf, sizeof(buf), "%#" PRIx64 "", addr);

  		printf(" %-34s |", buf);

  		printf(" %9llu/%-5lu | %9llu/%-5lu | %8lu | %8lu | %6.3f%%
  ",

  		       (unsigned long long)data->bytes_alloc,

  		       (unsigned long)data->bytes_alloc / data->hit,
  		       (unsigned long long)data->bytes_req,
  		       (unsigned long)data->bytes_req / data->hit,
  		       (unsigned long)data->hit,

  		       (unsigned long)data->pingpong,

  		       fragmentation(data->bytes_req, data->bytes_alloc));
  
  		next = rb_next(next);
  	}
  
  	if (n_lines == -1)

  		printf(" ...                                | ...             | ...             | ...    | ...      | ...   
  ");

  	printf("%.102s
  ", graph_dotted_line);

  }
  
  static void print_summary(void)
  {
  	printf("
  SUMMARY
  =======
  ");
  	printf("Total bytes requested: %lu
  ", total_requested);
  	printf("Total bytes allocated: %lu
  ", total_allocated);
  	printf("Total bytes wasted on internal fragmentation: %lu
  ",
  	       total_allocated - total_requested);
  	printf("Internal fragmentation: %f%%
  ",
  	       fragmentation(total_requested, total_allocated));

  	printf("Cross CPU allocations: %lu/%lu
  ", nr_cross_allocs, nr_allocs);

  }

  static void print_result(struct perf_session *session)

  {
  	if (caller_flag)

  		__print_result(&root_caller_sorted, session, caller_lines, 1);

  	if (alloc_flag)

  		__print_result(&root_alloc_sorted, session, alloc_lines, 0);

  	print_summary();
  }

  struct sort_dimension {
  	const char		name[20];
  	sort_fn_t		cmp;
  	struct list_head	list;
  };
  
  static LIST_HEAD(caller_sort);
  static LIST_HEAD(alloc_sort);

  static void sort_insert(struct rb_root *root, struct alloc_stat *data,

  			struct list_head *sort_list)

  {
  	struct rb_node **new = &(root->rb_node);
  	struct rb_node *parent = NULL;

  	struct sort_dimension *sort;

  
  	while (*new) {
  		struct alloc_stat *this;

  		int cmp = 0;

  
  		this = rb_entry(*new, struct alloc_stat, node);
  		parent = *new;

  		list_for_each_entry(sort, sort_list, list) {
  			cmp = sort->cmp(data, this);
  			if (cmp)
  				break;
  		}

  
  		if (cmp > 0)
  			new = &((*new)->rb_left);
  		else
  			new = &((*new)->rb_right);
  	}
  
  	rb_link_node(&data->node, parent, new);
  	rb_insert_color(&data->node, root);
  }
  
  static void __sort_result(struct rb_root *root, struct rb_root *root_sorted,

  			  struct list_head *sort_list)

  {
  	struct rb_node *node;
  	struct alloc_stat *data;
  
  	for (;;) {
  		node = rb_first(root);
  		if (!node)
  			break;
  
  		rb_erase(node, root);
  		data = rb_entry(node, struct alloc_stat, node);

  		sort_insert(root_sorted, data, sort_list);

  	}
  }
  
  static void sort_result(void)
  {

  	__sort_result(&root_alloc_stat, &root_alloc_sorted, &alloc_sort);
  	__sort_result(&root_caller_stat, &root_caller_sorted, &caller_sort);

  }
  
  static int __cmd_kmem(void)
  {

  	int err = -EINVAL;

  	struct perf_session *session = perf_session__new(input_name, O_RDONLY,
  							 0, false, &event_ops);

  	if (session == NULL)
  		return -ENOMEM;

  	if (perf_session__create_kernel_maps(session) < 0)
  		goto out_delete;

  	if (!perf_session__has_traces(session, "kmem record"))
  		goto out_delete;

  	setup_pager();

  	err = perf_session__process_events(session, &event_ops);
  	if (err != 0)
  		goto out_delete;

  	sort_result();

  	print_result(session);
  out_delete:
  	perf_session__delete(session);
  	return err;

  }
  
  static const char * const kmem_usage[] = {

  	"perf kmem [<options>] {record|stat}",

  	NULL
  };

  static int ptr_cmp(struct alloc_stat *l, struct alloc_stat *r)
  {
  	if (l->ptr < r->ptr)
  		return -1;
  	else if (l->ptr > r->ptr)
  		return 1;
  	return 0;
  }

  static struct sort_dimension ptr_sort_dimension = {
  	.name	= "ptr",
  	.cmp	= ptr_cmp,
  };

  static int callsite_cmp(struct alloc_stat *l, struct alloc_stat *r)
  {
  	if (l->call_site < r->call_site)
  		return -1;
  	else if (l->call_site > r->call_site)
  		return 1;
  	return 0;
  }

  static struct sort_dimension callsite_sort_dimension = {
  	.name	= "callsite",
  	.cmp	= callsite_cmp,
  };

  static int hit_cmp(struct alloc_stat *l, struct alloc_stat *r)
  {
  	if (l->hit < r->hit)
  		return -1;
  	else if (l->hit > r->hit)
  		return 1;
  	return 0;
  }

  static struct sort_dimension hit_sort_dimension = {
  	.name	= "hit",
  	.cmp	= hit_cmp,
  };

  static int bytes_cmp(struct alloc_stat *l, struct alloc_stat *r)
  {
  	if (l->bytes_alloc < r->bytes_alloc)
  		return -1;
  	else if (l->bytes_alloc > r->bytes_alloc)
  		return 1;
  	return 0;
  }

  static struct sort_dimension bytes_sort_dimension = {
  	.name	= "bytes",
  	.cmp	= bytes_cmp,
  };

  static int frag_cmp(struct alloc_stat *l, struct alloc_stat *r)
  {
  	double x, y;
  
  	x = fragmentation(l->bytes_req, l->bytes_alloc);
  	y = fragmentation(r->bytes_req, r->bytes_alloc);
  
  	if (x < y)
  		return -1;
  	else if (x > y)
  		return 1;
  	return 0;
  }

  static struct sort_dimension frag_sort_dimension = {
  	.name	= "frag",
  	.cmp	= frag_cmp,
  };

  static int pingpong_cmp(struct alloc_stat *l, struct alloc_stat *r)
  {
  	if (l->pingpong < r->pingpong)
  		return -1;
  	else if (l->pingpong > r->pingpong)
  		return 1;
  	return 0;
  }
  
  static struct sort_dimension pingpong_sort_dimension = {
  	.name	= "pingpong",
  	.cmp	= pingpong_cmp,
  };

  static struct sort_dimension *avail_sorts[] = {
  	&ptr_sort_dimension,
  	&callsite_sort_dimension,
  	&hit_sort_dimension,
  	&bytes_sort_dimension,
  	&frag_sort_dimension,

  	&pingpong_sort_dimension,

  };
  
  #define NUM_AVAIL_SORTS	\
  	(int)(sizeof(avail_sorts) / sizeof(struct sort_dimension *))
  
  static int sort_dimension__add(const char *tok, struct list_head *list)
  {
  	struct sort_dimension *sort;
  	int i;
  
  	for (i = 0; i < NUM_AVAIL_SORTS; i++) {
  		if (!strcmp(avail_sorts[i]->name, tok)) {
  			sort = malloc(sizeof(*sort));
  			if (!sort)
  				die("malloc");
  			memcpy(sort, avail_sorts[i], sizeof(*sort));
  			list_add_tail(&sort->list, list);
  			return 0;
  		}
  	}
  
  	return -1;
  }
  
  static int setup_sorting(struct list_head *sort_list, const char *arg)
  {
  	char *tok;
  	char *str = strdup(arg);
  
  	if (!str)
  		die("strdup");
  
  	while (true) {
  		tok = strsep(&str, ",");
  		if (!tok)
  			break;
  		if (sort_dimension__add(tok, sort_list) < 0) {
  			error("Unknown --sort key: '%s'", tok);
  			return -1;
  		}
  	}
  
  	free(str);
  	return 0;
  }

  static int parse_sort_opt(const struct option *opt __used,
  			  const char *arg, int unset __used)
  {

  	if (!arg)
  		return -1;

  	if (caller_flag > alloc_flag)

  		return setup_sorting(&caller_sort, arg);

  	else

  		return setup_sorting(&alloc_sort, arg);

  
  	return 0;
  }

  static int parse_caller_opt(const struct option *opt __used,

  			  const char *arg __used, int unset __used)

  {

  	caller_flag = (alloc_flag + 1);
  	return 0;
  }

  static int parse_alloc_opt(const struct option *opt __used,

  			  const char *arg __used, int unset __used)

  {
  	alloc_flag = (caller_flag + 1);

  	return 0;
  }
  
  static int parse_line_opt(const struct option *opt __used,
  			  const char *arg, int unset __used)
  {
  	int lines;
  
  	if (!arg)
  		return -1;
  
  	lines = strtoul(arg, NULL, 10);
  
  	if (caller_flag > alloc_flag)
  		caller_lines = lines;
  	else
  		alloc_lines = lines;
  
  	return 0;
  }
  
  static const struct option kmem_options[] = {
  	OPT_STRING('i', "input", &input_name, "file",
  		   "input file name"),

  	OPT_CALLBACK_NOOPT(0, "caller", NULL, NULL,
  			   "show per-callsite statistics",
  			   parse_caller_opt),
  	OPT_CALLBACK_NOOPT(0, "alloc", NULL, NULL,
  			   "show per-allocation statistics",
  			   parse_alloc_opt),

  	OPT_CALLBACK('s', "sort", NULL, "key[,key2...]",

  		     "sort by keys: ptr, call_site, bytes, hit, pingpong, frag",

  		     parse_sort_opt),
  	OPT_CALLBACK('l', "line", NULL, "num",

  		     "show n lines",

  		     parse_line_opt),

  	OPT_BOOLEAN(0, "raw-ip", &raw_ip, "show raw ip instead of symbol"),

  	OPT_END()
  };
  
  static const char *record_args[] = {
  	"record",
  	"-a",
  	"-R",

  	"-f",
  	"-c", "1",
  	"-e", "kmem:kmalloc",
  	"-e", "kmem:kmalloc_node",
  	"-e", "kmem:kfree",
  	"-e", "kmem:kmem_cache_alloc",
  	"-e", "kmem:kmem_cache_alloc_node",
  	"-e", "kmem:kmem_cache_free",
  };
  
  static int __cmd_record(int argc, const char **argv)
  {
  	unsigned int rec_argc, i, j;
  	const char **rec_argv;
  
  	rec_argc = ARRAY_SIZE(record_args) + argc - 1;
  	rec_argv = calloc(rec_argc + 1, sizeof(char *));

  	if (rec_argv == NULL)
  		return -ENOMEM;

  	for (i = 0; i < ARRAY_SIZE(record_args); i++)
  		rec_argv[i] = strdup(record_args[i]);
  
  	for (j = 1; j < (unsigned int)argc; j++, i++)
  		rec_argv[i] = argv[j];
  
  	return cmd_record(i, rec_argv, NULL);
  }
  
  int cmd_kmem(int argc, const char **argv, const char *prefix __used)
  {

  	argc = parse_options(argc, argv, kmem_options, kmem_usage, 0);

  	if (!argc)

  		usage_with_options(kmem_usage, kmem_options);

  	symbol__init();

  	if (!strncmp(argv[0], "rec", 3)) {
  		return __cmd_record(argc, argv);
  	} else if (!strcmp(argv[0], "stat")) {
  		setup_cpunode_map();
  
  		if (list_empty(&caller_sort))
  			setup_sorting(&caller_sort, default_sort_order);
  		if (list_empty(&alloc_sort))
  			setup_sorting(&alloc_sort, default_sort_order);

  		return __cmd_kmem();

  	} else
  		usage_with_options(kmem_usage, kmem_options);

  	return 0;

  }