Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/mm/percpu-stats.c b/mm/percpu-stats.c
index b5fdd43..a5a8b22 100644
--- a/mm/percpu-stats.c
+++ b/mm/percpu-stats.c
@@ -1,11 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * mm/percpu-debug.c
  *
  * Copyright (C) 2017		Facebook Inc.
  * Copyright (C) 2017		Dennis Zhou <dennisz@fb.com>
  *
- * This file is released under the GPLv2.
- *
  * Prints statistics about the percpu allocator and backing chunks.
  */
 #include <linux/debugfs.h>
@@ -53,6 +52,7 @@
 static void chunk_map_stats(struct seq_file *m, struct pcpu_chunk *chunk,
 			    int *buffer)
 {
+	struct pcpu_block_md *chunk_md = &chunk->chunk_md;
 	int i, last_alloc, as_len, start, end;
 	int *alloc_sizes, *p;
 	/* statistics */
@@ -121,9 +121,9 @@
 	P("nr_alloc", chunk->nr_alloc);
 	P("max_alloc_size", chunk->max_alloc_size);
 	P("empty_pop_pages", chunk->nr_empty_pop_pages);
-	P("first_bit", chunk->first_bit);
+	P("first_bit", chunk_md->first_free);
 	P("free_bytes", chunk->free_bytes);
-	P("contig_bytes", chunk->contig_bits * PCPU_MIN_ALLOC_SIZE);
+	P("contig_bytes", chunk_md->contig_hint * PCPU_MIN_ALLOC_SIZE);
 	P("sum_frag", sum_frag);
 	P("max_frag", max_frag);
 	P("cur_min_alloc", cur_min_alloc);