LXR linux/tools/vm/page_owner

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * User-space helper to sort the output of /sys/kernel/debug/page_owner
   4 *
   5 * Example use:
   6 * cat /sys/kernel/debug/page_owner > page_owner_full.txt
   7 * grep -v ^PFN page_owner_full.txt > page_owner.txt
   8 * ./sort page_owner.txt sorted_page_owner.txt
   9*/
  10
  11#include <stdio.h>
  12#include <stdlib.h>
  13#include <sys/types.h>
  14#include <sys/stat.h>
  15#include <fcntl.h>
  16#include <unistd.h>
  17#include <string.h>
  18
  19struct block_list {
  20        char *txt;
  21        int len;
  22        int num;
  23};
  24
  25
  26static struct block_list *list;
  27static int list_size;
  28static int max_size;
  29
  30struct block_list *block_head;
  31
  32int read_block(char *buf, int buf_size, FILE *fin)
  33{
  34        char *curr = buf, *const buf_end = buf + buf_size;
  35
  36        while (buf_end - curr > 1 && fgets(curr, buf_end - curr, fin)) {
  37                if (*curr == '\n') /* empty line */
  38                        return curr - buf;
  39                curr += strlen(curr);
  40        }
  41
  42        return -1; /* EOF or no space left in buf. */
  43}
  44
  45static int compare_txt(const void *p1, const void *p2)
  46{
  47        const struct block_list *l1 = p1, *l2 = p2;
  48
  49        return strcmp(l1->txt, l2->txt);
  50}
  51
  52static int compare_num(const void *p1, const void *p2)
  53{
  54        const struct block_list *l1 = p1, *l2 = p2;
  55
  56        return l2->num - l1->num;
  57}
  58
  59static void add_list(char *buf, int len)
  60{
  61        if (list_size != 0 &&
  62            len == list[list_size-1].len &&
  63            memcmp(buf, list[list_size-1].txt, len) == 0) {
  64                list[list_size-1].num++;
  65                return;
  66        }
  67        if (list_size == max_size) {
  68                printf("max_size too small??\n");
  69                exit(1);
  70        }
  71        list[list_size].txt = malloc(len+1);
  72        list[list_size].len = len;
  73        list[list_size].num = 1;
  74        memcpy(list[list_size].txt, buf, len);
  75        list[list_size].txt[len] = 0;
  76        list_size++;
  77        if (list_size % 1000 == 0) {
  78                printf("loaded %d\r", list_size);
  79                fflush(stdout);
  80        }
  81}
  82
  83#define BUF_SIZE        (128 * 1024)
  84
  85int main(int argc, char **argv)
  86{
  87        FILE *fin, *fout;
  88        char *buf;
  89        int ret, i, count;
  90        struct block_list *list2;
  91        struct stat st;
  92
  93        if (argc < 3) {
  94                printf("Usage: ./program <input> <output>\n");
  95                perror("open: ");
  96                exit(1);
  97        }
  98
  99        fin = fopen(argv[1], "r");
 100        fout = fopen(argv[2], "w");
 101        if (!fin || !fout) {
 102                printf("Usage: ./program <input> <output>\n");
 103                perror("open: ");
 104                exit(1);
 105        }
 106
 107        fstat(fileno(fin), &st);
 108        max_size = st.st_size / 100; /* hack ... */
 109
 110        list = malloc(max_size * sizeof(*list));
 111        buf = malloc(BUF_SIZE);
 112        if (!list || !buf) {
 113                printf("Out of memory\n");
 114                exit(1);
 115        }
 116
 117        for ( ; ; ) {
 118                ret = read_block(buf, BUF_SIZE, fin);
 119                if (ret < 0)
 120                        break;
 121
 122                add_list(buf, ret);
 123        }
 124
 125        printf("loaded %d\n", list_size);
 126
 127        printf("sorting ....\n");
 128
 129        qsort(list, list_size, sizeof(list[0]), compare_txt);
 130
 131        list2 = malloc(sizeof(*list) * list_size);
 132
 133        printf("culling\n");
 134
 135        for (i = count = 0; i < list_size; i++) {
 136                if (count == 0 ||
 137                    strcmp(list2[count-1].txt, list[i].txt) != 0) {
 138                        list2[count++] = list[i];
 139                } else {
 140                        list2[count-1].num += list[i].num;
 141                }
 142        }
 143
 144        qsort(list2, count, sizeof(list[0]), compare_num);
 145
 146        for (i = 0; i < count; i++)
 147                fprintf(fout, "%d times:\n%s\n", list2[i].num, list2[i].txt);
 148
 149        return 0;
 150}
 151