1/*
  2 * User-space helper to sort the output of /sys/kernel/debug/page_owner
  3 *
  4 * Example use:
  5 * cat /sys/kernel/debug/page_owner > page_owner_full.txt
  6 * grep -v ^PFN page_owner_full.txt > page_owner.txt
  7 * ./sort page_owner.txt sorted_page_owner.txt
  8*/
  9
 10#include <stdio.h>
 11#include <stdlib.h>
 12#include <sys/types.h>
 13#include <sys/stat.h>
 14#include <fcntl.h>
 15#include <unistd.h>
 16#include <string.h>
 17
 18struct block_list {
 19	char *txt;
 20	int len;
 21	int num;
 22};
 23
 24
 25static struct block_list *list;
 26static int list_size;
 27static int max_size;
 28
 29struct block_list *block_head;
 30
 31int read_block(char *buf, int buf_size, FILE *fin)
 32{
 33	char *curr = buf, *const buf_end = buf + buf_size;
 34
 35	while (buf_end - curr > 1 && fgets(curr, buf_end - curr, fin)) {
 36		if (*curr == '\n') /* empty line */
 37			return curr - buf;
 38		curr += strlen(curr);
 39	}
 40
 41	return -1; /* EOF or no space left in buf. */
 42}
 43
 44static int compare_txt(const void *p1, const void *p2)
 45{
 46	const struct block_list *l1 = p1, *l2 = p2;
 47
 48	return strcmp(l1->txt, l2->txt);
 49}
 50
 51static int compare_num(const void *p1, const void *p2)
 52{
 53	const struct block_list *l1 = p1, *l2 = p2;
 54
 55	return l2->num - l1->num;
 56}
 57
 58static void add_list(char *buf, int len)
 59{
 60	if (list_size != 0 &&
 61	    len == list[list_size-1].len &&
 62	    memcmp(buf, list[list_size-1].txt, len) == 0) {
 63		list[list_size-1].num++;
 64		return;
 65	}
 66	if (list_size == max_size) {
 67		printf("max_size too small??\n");
 68		exit(1);
 69	}
 70	list[list_size].txt = malloc(len+1);
 71	list[list_size].len = len;
 72	list[list_size].num = 1;
 73	memcpy(list[list_size].txt, buf, len);
 74	list[list_size].txt[len] = 0;
 75	list_size++;
 76	if (list_size % 1000 == 0) {
 77		printf("loaded %d\r", list_size);
 78		fflush(stdout);
 79	}
 80}
 81
 82#define BUF_SIZE	(128 * 1024)
 83
 84int main(int argc, char **argv)
 85{
 86	FILE *fin, *fout;
 87	char *buf;
 88	int ret, i, count;
 89	struct block_list *list2;
 90	struct stat st;
 91
 92	if (argc < 3) {
 93		printf("Usage: ./program <input> <output>\n");
 94		perror("open: ");
 95		exit(1);
 96	}
 97
 98	fin = fopen(argv[1], "r");
 99	fout = fopen(argv[2], "w");
100	if (!fin || !fout) {
101		printf("Usage: ./program <input> <output>\n");
102		perror("open: ");
103		exit(1);
104	}
105
106	fstat(fileno(fin), &st);
107	max_size = st.st_size / 100; /* hack ... */
108
109	list = malloc(max_size * sizeof(*list));
110	buf = malloc(BUF_SIZE);
111	if (!list || !buf) {
112		printf("Out of memory\n");
113		exit(1);
114	}
115
116	for ( ; ; ) {
117		ret = read_block(buf, BUF_SIZE, fin);
118		if (ret < 0)
119			break;
120
121		add_list(buf, ret);
122	}
123
124	printf("loaded %d\n", list_size);
125
126	printf("sorting ....\n");
127
128	qsort(list, list_size, sizeof(list[0]), compare_txt);
129
130	list2 = malloc(sizeof(*list) * list_size);
131
132	printf("culling\n");
133
134	for (i = count = 0; i < list_size; i++) {
135		if (count == 0 ||
136		    strcmp(list2[count-1].txt, list[i].txt) != 0) {
137			list2[count++] = list[i];
138		} else {
139			list2[count-1].num += list[i].num;
140		}
141	}
142
143	qsort(list2, count, sizeof(list[0]), compare_num);
144
145	for (i = 0; i < count; i++)
146		fprintf(fout, "%d times:\n%s\n", list2[i].num, list2[i].txt);
147
148	return 0;
149}