tools/vm/page_owner_sort: fix three trivival places

The following adjustments are made:

1. Instead of using another array to cull the blocks after sorting,
   reuse the old array.  So there is no need to malloc a new array.

2. When enabling '-f' option to filter out the blocks which have been
   released, only add those have not been released in the list, rather
   than add all of blocks in the list and then do the filtering when
   printing the result.

3. When enabling '-c' option to cull the blocks by comparing
   stacktrace, print the stacetrace rather than the total block.

Link: https://lkml.kernel.org/r/20220306030640.43054-1-yejiajian2018@email.szu.edu.cnSigned-off-by: Jiajian Ye <yejiajian2018@email.szu.edu.cn>
Cc: <hanshenghong2019@email.szu.edu.cn>
Cc: Sean Anderson <seanga2@gmail.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Yixuan Cao <caoyixuan2019@email.szu.edu.cn>
Cc: <zhangyinan2019@email.szu.edu.cn>
Cc: Zhenliang Wei <weizhenliang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

tools/vm/page_owner_sort.c

@@ -42,6 +42,8 @@ static regex_t free_ts_nsec_pattern;
 static struct block_list *list;
 static int list_size;
 static int max_size;
+static int cull_st;
+static int filter;
 
 int read_block(char *buf, int buf_size, FILE *fin)
 {
@@ -245,6 +247,9 @@ static void add_list(char *buf, int len)
 		exit(1);
 	}
 
+	list[list_size].free_ts_nsec = get_free_ts_nsec(buf);
+	if (filter == 1 && list[list_size].free_ts_nsec != 0)
+		return;
 	list[list_size].txt = malloc(len+1);
 	if (!list[list_size].txt) {
 		printf("Out of memory\n");
@@ -257,10 +262,11 @@ static void add_list(char *buf, int len)
 	memcpy(list[list_size].txt, buf, len);
 	list[list_size].txt[len] = 0;
 	list[list_size].stacktrace = strchr(list[list_size].txt, '\n') ?: "";
+	if (*list[list_size].stacktrace == '\n')
+		list[list_size].stacktrace++;
 	list[list_size].pid = get_pid(buf);
 	list[list_size].tgid = get_tgid(buf);
 	list[list_size].ts_nsec = get_ts_nsec(buf);
-	list[list_size].free_ts_nsec = get_free_ts_nsec(buf);
 	list_size++;
 	if (list_size % 1000 == 0) {
 		printf("loaded %d\r", list_size);
@@ -288,12 +294,9 @@ static void usage(void)
 int main(int argc, char **argv)
 {
 	int (*cmp)(const void *, const void *) = compare_num;
-	int cull_st = 0;
-	int filter = 0;
 	FILE *fin, *fout;
 	char *buf;
 	int ret, i, count;
-	struct block_list *list2;
 	struct stat st;
 	int opt;
 
@@ -376,11 +379,7 @@ int main(int argc, char **argv)
 	else
 		qsort(list, list_size, sizeof(list[0]), compare_txt);
 
-	list2 = malloc(sizeof(*list) * list_size);
-	if (!list2) {
-		printf("Out of memory\n");
-		exit(1);
-	}
+
 
 	printf("culling\n");
 
@@ -388,21 +387,23 @@ int main(int argc, char **argv)
 
 	for (i = count = 0; i < list_size; i++) {
 		if (count == 0 ||
-		    strcmp(*(&list2[count-1].txt+offset), *(&list[i].txt+offset)) != 0) {
-			list2[count++] = list[i];
+		    strcmp(*(&list[count-1].txt+offset), *(&list[i].txt+offset)) != 0) {
+			list[count++] = list[i];
 		} else {
-			list2[count-1].num += list[i].num;
-			list2[count-1].page_num += list[i].page_num;
+			list[count-1].num += list[i].num;
+			list[count-1].page_num += list[i].page_num;
 		}
 	}
 
-	qsort(list2, count, sizeof(list[0]), cmp);
+	qsort(list, count, sizeof(list[0]), cmp);
 
 	for (i = 0; i < count; i++) {
-		if (filter == 1 && list2[i].free_ts_nsec != 0)
-			continue;
+		if (cull_st == 0)
+			fprintf(fout, "%d times, %d pages:\n%s\n",
+					list[i].num, list[i].page_num, list[i].txt);
+		else
 			fprintf(fout, "%d times, %d pages:\n%s\n",
-				list2[i].num, list2[i].page_num, list2[i].txt);
+					list[i].num, list[i].page_num, list[i].stacktrace);
 	}
 	regfree(&order_pattern);
 	regfree(&pid_pattern);